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PubMed1986

Regional outcome in oropharyngeal and pharyngolaryngeal cancer treated with high dose per fraction radiotherapy. Analysis of neck disease response in 1646 cases.

Out of a series of 1666 consecutive patients with squamous cell carcinoma of oropharynx and pharyngolarynx, 1646 were evaluable at a 3-year interval following radical radiation therapy. The actuarial 3-year nodal control rate using the AJC classification was: N0 98%, N1 90%, N2 88%, N3 71% when the primary was controlled. The regional outcome is influenced by clinical features such as nodal size, multiplicity and fixity. Cervical recurrence frequency is higher for pharyngolaryngeal carcinoma than for oropharyngeal cancer. The impact of the treatment planning on regional control is discussed. Due to the of concomitant boosting of nodes, cervical metastases were treated according to a type of accelerated fractionation schedule with weekly doses of 12-15 Gy for a total of 70-85 Gy in 75% of the cases. Clear-cut dose control relationships are demonstrated for nodes larger than 3 cm in diameter. Overboosting residual cervical disease fails to yield a better nodal control. Comparative analysis is established between results obtained with this high dose per fraction radiotherapy schedule, conventional regimens of irradiation and other new approaches, combining chemical and physical agents. Therapeutic implications are also derived to define adequate field coverage.

Carcinoma, Squamous Cell↗

PubMedDate not supplied

Identification and classification of the causes of events in transfusion medicine.

BACKGROUND: Transfusion medicine lacks a standard method for the systematic collection and analysis of event reports. Review of event reports from the Food and Drug Administration (FDA) showed a relative paucity of information on event causation. Thus, a causal analysis method was developed as part of a prototype Medical Event Reporting System for Transfusion Medicine (MERS-TM). STUDY DESIGN AND METHODS: MERS-TM functions within existing quality assurance systems and utilizes descriptive coding and causal classification schemes. The descriptive classification system, based upon current FDA coding, was modified to meet participant needs. The Eindhoven Classification Model (Medical Version) was adopted for causal classification and analysis. Inter-rater reliability for the MERS-TM and among participating organizations was performed with the development group in the United States and with a safety science research group in the Netherlands. The MERS-TM was then tested with events reported by participants. RESULTS: Data from 503 event reports from two blood centers and two transfusion services are discussed. The data showed multiple causes for events and more latent causes than previously recognized. The distribution of causes was remarkably similar to that in an industrial setting outside of medicine that uses the same classification approach. There was a high degree of inter-rater reliability when the same events were analyzed by quality assurance personnel in different participating organizations. These personnel found the method practical and useful for providing new insights into conditions producing undesired events. CONCLUSION: A generally applicable and reliable method for identifying and quantifying problems that exist throughout transfusion medicine will be a valuable addition to event reporting activity. By using a common taxonomy, participants can compare their experience with that of others. If proven as readily implementable and useful as shown in initial studies, MERS-TM is a potential standard for transfusion medicine.

Causality↗

PubMed2005

Treatment outcome in unilateral cleft lip and palate evaluated with the GOSLON yardstick: a meta-analysis of 1236 patients.

BACKGROUND: The goal of this study was to assess determinants for treatment outcome in unilateral cleft lip and palate, evaluated according to the Great Ormond Street London and Oslo (GOSLON) Yardstick and 5-year-index ratings by means of a meta-analysis. METHODS: Multiple databases were searched for publications in which patient groups were evaluated by GOSLON ranking or the GOSLON-like 5-year index. From the 15 selected publications, the following background variables could be extracted and were evaluated as determinants for treatment outcome in unilateral cleft lip and palate: year of birth, average age of the patient at the time of GOSLON classification, racial background, presence of Simonart's band, infant orthopedics, palatal closure before the age of 3 versus palatal closure at a later age, bone graft, and number of surgeons. RESULTS: The total number of patients included in the meta-analysis was 1236. Patients whose soft and hard palate were closed before the age of 3 presented significantly poorer (p = 0.003) GOSLON scores (mean score, 2.9; SD 0.4) than patients whose palate was closed at a later age (mean GOSLON score, 2.3; SD 0.2). CONCLUSIONS: Delayed palatal closure generally results in better dental arch relationships than early palatal closure. Well-designed, randomized clinical trials are required for further investigation of the optimal timing for palatal closure.

Age Factors↗

PubMed2002

The role of cerebrospinal fluid hypocretin measurement in the diagnosis of narcolepsy and other hypersomnias.

CONTEXT: Narcolepsy, a neurological disorder affecting 1 in 2000 individuals, is associated with HLA-DQB1*0602 and low cerebrospinal fluid (CSF) hypocretin (orexin) levels. OBJECTIVES: To delineate the spectrum of the hypocretin deficiency syndrome and to establish CSF hypocretin-1 measurements as a diagnostic tool for narcolepsy. DESIGN: Diagnosis, HLA-DQ, clinical data, the multiple sleep latency test (MSLT), and CSF hypocretin-1 were studied in a case series of patients with sleep disorders from 1999 to 2002. Signal detection analysis was used to determine the CSF hypocretin-1 levels best predictive for International Classification of Sleep Disorders (ICSD)-defined narcolepsy (blinded criterion standard). Clinical and demographic features were compared in narcoleptic subjects with and without low CSF hypocretin-1 levels. SETTING: Sleep disorder and neurology clinics in the United States and Europe, with biological testing performed at Stanford University, Stanford, Calif. PARTICIPANTS: There were 274 patients with narcolepsy; hypersomnia; obstructive sleep apnea; restless legs syndrome; insomnia; and atypical hypersomnia cases such as familial cases, narcolepsy without cataplexy or without HLA-DQB1*0602, recurrent hypersomnias, and symptomatic cases (eg, Parkinson disease, depression, Prader-Willi syndrome, Niemann-Pick disease type C). The subject group also included 296 controls (healthy and with neurological disorders). INTERVENTION: Venopuncture for HLA typing, lumbar puncture for CSF analysis, primary diagnosis using the International Classification of Sleep Disorders, Stanford Sleep Inventory for evaluation of narcolepsy, and sleep recording studies. MAIN OUTCOME MEASURES: Diagnostic threshold for CSF hypocretin-1, HLA-DQB1*0602 positivity, and clinical and polysomnographic features. RESULTS: HLA-DQB1*0602 frequency was increased in narcolepsy with typical cataplexy (93% vs 17% in controls), narcolepsy without cataplexy (56%), and in essential hypersomnia (52%). Hypocretin-1 levels below 110 pg/mL were diagnostic for narcolepsy. Values above 200 pg/mL were considered normal. Most subjects with low levels were HLA-DQB1*0602-positive narcolepsy-cataplexy patients. These patients did not always have abnormal MSLT. Rare subjects without cataplexy, DQB1*0602, and/or with secondary narcolepsy had low levels. Ten subjects with hypersomnia had intermediate levels, 7 with narcolepsy (often HLA negative, of secondary nature, and/or with atypical cataplexy or no cataplexy), and 1 with periodic hypersomnia. Healthy controls and subjects with other sleep disorders all had normal levels. Neurological subjects had generally normal levels (n = 194). Intermediate (n = 30) and low (n = 3) levels were observed in various acute neuropathologic conditions. CONCLUSIONS: Narcolepsy-cataplexy with hypocretin deficiency is a genuine disease entity. Measuring CSF hypocretin-1 is a definitive diagnostic test, provided that it is interpreted within the clinical context. It may be most useful in cases with cataplexy and when the MSLT is difficult to interpret (ie, in subjects already treated with psychoactive drugs or with other concurrent sleep disorders).

Adult↗

PubMed2001

Measurement of cholesterol in plasma and other body fluids.

Measurement of cholesterol has become increasingly important with recognition of its predictive association with cardiovascular diseases. Government and professional groups in the United States and other countries have developed consensus guidelines for using cholesterol and the lipoproteins in identifying patients at risk and in managing therapies. Accuracy in the measurements is essential not only for reliable classification of patients, but also in public health/wellness programs and in research. Laboratory experts have developed requisite analytical performance targets and guidelines for measurements. Manufacturers of diagnostic reagents and laboratories can assure accuracy by accessing the Cholesterol Reference Method Laboratory Network, which offers reference methods for total, high-density lipoprotein, and low-density lipoprotein cholesterol. Recommendations for controlling pre-analytical sources of variation and uniform interpretation of patient results facilitate reliable classification of patients. Driven by increasing workloads and the need for increased efficiency in laboratory testing, dramatic improvements have been made in recent years in automating laboratory analyzers, as well as the methods used for lipoprotein analysis. Newer technology allows multiple sequential measurements in the same cuvette, as well as point-of-care measurements, using strip tests and compact analyzers. Efforts continue to develop reliable, minimally invasive tests in body fluids other than serum.

Analysis of Variance↗

PubMed2006

Methods of clinical prediction.

The ability to predict clinical outcomes is of great importance to physicians and patients alike. Accordingly, multiple different methods have been used in an effort to accurately predict these outcomes. These methods include the development of scoring systems based on univariable and multivariable analysis, as well as models involving the use of neural network, nomograms, and classification and regression trees. The principles of these types of methods, as well as their advantages and disadvantages will be presented.

Forecasting↗

PubMed2003

In-utero transmission of quasispecies among human immunodeficiency virus type 1 genotypes.

Samples from infants infected in-utero by the human immunodeficiency virus type 1 (HIV-1) subtypes A, C, D, and recombinants from Dar es Salaam, Tanzania, were examined for the presence of viral genetic quasispecies. HIV-1 envelope diversity was measured on peripheral blood mononuclear cells collected within the first 48 h of life from 53 infants. Phylogenetic analysis of C2-C5 envelope nucleotide sequences was used for HIV-1 subtype classification. Forty-two of 53 samples (79%) showed a heteroduplex mobility assay (HMA) suggestive of transmission of a single quasispecies, while 21% showed infection with multiple quasispecies. No differences among HIV-1 subtypes were found in the proportion of single to multiple quasispecies transmitted in-utero (Likelihood ratio test, P = 0.83), nor were differences found among single to multiple quasispecies transmitted and maternal viral load (Mann-Whitney test, P = 0.44). This suggests that differences in perinatal transmission between subtypes we previously observed in this cohort could not be associated with the likelihood for multiple independent infections during in-utero infections.

Acquired Immunodeficiency Syndrome↗

PubMed2000

The use of the Mini-Nutritional Assessment (MNA) tool in elderly orthopaedic patients.

OBJECTIVE: To assess the use of the Mini-Nutritional Assessment (MNA) in elderly orthopaedic patients. DESIGN: An observation study assessing the nutritional status of female orthopaedic patients. SETTING: The orthopaedic wards of the Royal Surrey County Hospital. SUBJECTS: Forty-nine female patients aged 60-103 y; dietary records were obtained for 41 subjects and 36 subjects gave a blood sample for biochemical analysis. MAJOR OUTCOME METHODS: MNA questionnaire, anthropometry, plasma albumin, transferrin, C-reactive protein (CRP) levels and dietary analyses. RESULTS: The group as a whole had low mean values for body weight, albumin and transferrin and high CRP levels. In addition, the group had mean energy intakes well below the estimated average requirement (EAR) and mean intakes of vitamin D, magnesium, potassium, selenium and non-starch polysaccharides (NSP) were below the lower reference nutrient intakes (LRNI). The MNA screening section categorized 69% of the patients as requiring a full assessment (scored 11 or below), but for the purposes of the study the MNA was completed on all patients. The MNA assessment categorized 16% of the group as 'malnourished' (scored<17 points), 47% as 'at risk' (scored 17.5-23.5) and 37% as 'well nourished' (scored>23.5). Significant differences were found between the malnourished and well nourished groups for body weight (P<0.001), body mass index (BMI) (P<0.001), demiquet (P<0.001) and mindex (P<0. 001). Mean values for energy and nutrient intakes showed a clear stepwise increase across the three groups for all nutrients except sodium, with significant differences for protein (P<0.05), carbohydrate (P<0.05), riboflavin (P<0.05) niacin (P<0.05), pyridoxine (P<0.05), folate (P<0.05), calcium (P<0.05), selenium (P<0.05), iron (P<0.05) and NSP (P<0.05) intakes. Stepwise multiple regression analysis indicated that anthropometric assessments were the most predictive factors in the total MNA score. The sensitivity and specificity of the MNA was assessed in comparison with albumin levels, energy intake and mindex. The sensitivity of the MNA classification of those scoring less than 17 points in comparison with albumin levels, energy intake and mindex varied from 27 to 57% and the specificity was 66-100%. This was compared with the sensitivity and specificity of using a score of less than 23.5 on the MNA to predict malnourished individuals. Using this cut-off the sensitivity ranged from 75 to 100%, but the specificity declined to between 37 and 50%. CONCLUSIONS: The results suggest that the MNA is a useful diagnostic tool in the identification of elderly patients at risk from malnutrition and those who are malnourished in this hospital setting. SPONSORSHIP: Nestlé Clinical Nutrition, Croydon, Surrey.

Aged↗

PubMed1996

Subtypes of incarcerated delinquents constructed via cluster analysis.

The MMPI and Jesness Inventory were used to construct groupings of juvenile delinquents homogeneous with respect to personality characteristics. Subjects were 191 incarcerated juvenile delinquents, aged 12 to 19. All participants had been adjudicated on one or more serious offenses. Five subtypes of delinquents were identified. They included an alienated, unsocialized group, an insecure-anxious group, a group reporting limited difficulties with peers but alienated from adults, a group with no apparent emotional disturbance, and a group with multiple elevations. Significant differences between clusters with regard to self-reported explosiveness, suicidality, gang activities, substance abuse, history of sexual abuse, and delusions and hallucinations were identified. Discriminant function analysis was then used to support the generalizability of the classification system to an independent sample. Eighty per cent of the second sample were accurately classified. The subtypes identified are compared to delinquent classification systems developed previously.

Adult↗

PubMed1996

Age, body composition, aerobic fitness and health condition as risk factors for musculoskeletal injuries in conscripts.

Musculoskeletal injuries occur frequently in connection with physical activity. More information was sought on pretraining factors that may predispose to such injuries. Data were obtained on the age, height, weight, aerobic fitness as measured by a 3000-m run test, and health as assessed on the basis of a medical examination, of 912 male conscripts prior to an 8-week period of basic military and physical training. Injuries were registered as they occurred by doctors attached to the training camp. Every fourth to fifth conscript suffered one or more musculo-skeletal injuries during basic training. Achilles tendinitis, low back pain, periostitis or compartment syndromes, and overuse knee injuries were the most frequent diagnosis groups. In 74% of the injuries, a tentative cause was related to organized service activities. According to univariate analyses, risk factors were age over 23 years, high body mass index (BMI), slow run times and dysfunctions of the back or lower limbs. A lower classification of mental health, but not dysfunctions of the lower limbs, was an additional risk factor if only injuries with causes connected with organized service activities were considered. Height and weight were not associated with injuries. In multiple logistic regression analysis, age and 3000-m run times were masked by correction for BMI, while BMI, dysfunctions of the back and lower limbs, and reduced mental health showed the same significance as in the univariate analyses.

Achilles Tendon↗

PubMed2005

[A revised scheme for LeFort classification of upper jaw fractures].

OBJECTIVE: To put forward a revised scheme on LeFort classification for the upper jaw fractures. METHODS: 193 consecutive cases with the primary diagnoses of upper jaw fractures were involved in this study, for each one of which water's and CT scan were available to decide the fracture site and pattern. Data were filed in term of classification items as LeFort I, II and III fracture, as well as sagittal fracture and alveolar fracture. Statistical analysis was done to validate the meliorating thought on and revised scheme on LeFort classification. RESULTS: It was validated that of 185 cases with upper jaw fractures only 30.81% which presented single-line fracture and 34.06% which presented multiple-line fracture were covered with LeFort classification. Additional 13.51% with single-line fracture and 21.61% with multiple-line fracture could be included when LeFort classification was extended with increase of items of sagittal fracture and alveolar fracture. Further results revealed that among total 344 sites or fracture lines included in 193 cases, 81.10% could be diagnosed fracture pattern of LeFort classification. Of 65 fracture sites presenting LeFort III type, 92.31% were concomitant with LeFort II type or LeFort I and II type, very few being alone. CONCLUSIONS: A revised classification was proposeded that upper jaw fractures could be classified into four types as follows: (1) high horizontal fracture (corresponding to LeFort II and III type), (2) low horizontal fracture (corresponding to LeFort I type), (3) sagittal fracture (including midline and para-midline fracture) and (4) alveolar fracture.

Adolescent↗

PubMed1983

A computer based decision-making model for poultry inspection.

In an attempt to develop a predictive model for poultry inspection at processing plants, a systems research design was developed to examine poultry population health dynamics from hatching to processing. Five cooperating Alabama poultry firms with 5 to 7 growers from each firm were identified to form the study unit. The farms were stratified to represent good, average, and poor producers. Via epidemiologic causal diagrams, variables with potential influence on poultry condemnation due to diseases were identified for hatchery, broiler, and processing subsystems. Field and/or laboratory data were generated for each study unit and for each variable. Using stepwise multiple regression and discriminant analysis, a predictor model with a multiple correlation coefficient (R) of 0.91 and multiple coefficient of determination (R2) of 0.82 was developed. A discriminant analysis model for classifying a flock into high or low condemnation group, using 0.1% to 2.0% as the demarcation line, was also developed. This latter model had overall correct classification probabilities ranging from 0.88 to 1.0. The 2 decision-making models were then computerized, using Beginner's All-purpose Symbolic Instruction Code (BASIC). On the day of processing, the grower provides the inspector with selected information, which is entered on a computer. Alternatives for scaled-down inspection or others are then systematically evaluated by the computer, and decision-making information is provided to the user.

Alabama↗

PubMed1995

Epidemiology of hospitalization for acute upper gastrointestinal hemorrhage: a population-based study.

OBJECTIVES: To obtain epidemiological data on hospitalization for acute upper gastrointestinal hemorrhage (AUGIH) in a demographically defined population. METHODS: Adults hospitalized in 1991 with AUGIH [from a San Diego health maintenance organization (270,699 adult members)] were identified from discharge codes in the International Classification of Diseases, 9th Revision, Clinical Modifications, and their records were reviewed. RESULTS: There were 276 hospitalizations among 258 patients, an annual incidence rate of 102.0 hospitalizations per 100,000. Patient analysis, including the first admission of 15 patients with multiple hospitalizations, revealed rates of 128.3 in males and 65.8 in females. The rate increased with age in males (p = 0.008) and females (p = 0.001) more than 30-fold between the 3rd and 9th decades of life. AUGIH started before admission in 242 (93.8%) patients and after admission for other disorders in 16 (6.2%) patients. Endoscopy was performed in 241 (93.4%) patients. Diagnoses were: peptic ulcer, 159 (61.6%); mucosal erosive disease, 37 (14.3%); varices, 16 (6.2%); miscellaneous, 25 (9.7%); and unknown, 21 (8.1%). Peptic ulcer patients were similar to other patients (mean +/- SE) in age [60.6 +/- 1.2 vs. 60.7 +/- 1.5 yr] and gender [104 (65.4%) vs. 60 (60.6%) males], but were more often nonsteroidal anti-inflammatory drug (NSAID)-users [87 (54.7%) vs. 34 (34.3%) (p = 0.002)]. Older age, female gender, and NSAID use independently predicted gastric ulcer (p < or = 0.03). The severity of bleeding was similar in patients with peptic ulcers and in those with mucosal erosive disease and was not related to NSAID use in peptic ulcer patients. Patients whose AUGIH started after admission were older than those whose AUGIH began before admission [70.4 +/- 2.9 vs. 60.0 +/- 1.0 yr (p = 0.002)], and they had a higher mortality rate [4 (25%) vs. 9 (3.7%) (p = 0.005)]. CONCLUSIONS: 1) The annual incidence of hospitalization for AUGIH was 102.0 per 100,000, increased markedly with age, and was twice as high in males as in females. 2) Peptic ulcer was the most common cause. 3) Gastric ulcer was associated with older age, female gender, and NSAID use. 4) Mortality rates were high when AUGIH started after hospitalization for another disorder.

Acute Disease↗

PubMed2005

Prognostic evaluation of the new American Joint Committee on Cancer/International Union Against Cancer staging system for hepatocellular carcinoma: analysis of 112 cirrhotic patients resected for hepatocellular carcinoma.

BACKGROUND: In 2002, the American Joint Committee on Cancer and the International Union Against Cancer redefined the T-classification for hepatocellular carcinoma, shifting the cutoff value for tumor size from 2 to 5 cm and giving more emphasis to vascular invasion. METHODS: A retrospective cohort study was conducted on 223 consecutive patients with hepatocellular carcinoma observed between 1990 and 2002. One hundred twelve were resected and considered for retrospective analysis. Univariate and multivariate analyses were performed on several clinicopathologic variables. After classification according to each staging system, the long-term survival of different stages was compared. The prognostic value of each staging system was further evaluated by entering each stage, in turn, into the Cox regression model with other clinicopathologic variables. The median follow-up was 19 months. RESULTS: On multivariate analysis, the viral etiology of cirrhosis and the presence of multiple nodules were independent prognostic factors. When the new staging system was entered into the multivariate analysis, it was the only independent factor (P = .02). When stratified according to the old tumor-node-metastasis system, there were no significant differences in the survival between stage I and II (P = .14) or between stage IIIA and IVA (P = .33); only the survival of stage II and IIIA was different (P < .01). When stratified according to the new tumor-node-metastasis system, there were significant differences between stage I and II (71.7% vs. 54.7%; P = .02). CONCLUSIONS: The new staging system is a more reliable and objective method for T classification. It is easy to use in clinical practice and is better at stratifying curatively resected patients with respect to prognosis.

Aged↗

PubMed1989

Genetic analysis of human deoxyribonuclease I by immunoblotting and the zymogram method following isoelectric focusing.

We have devised two independent detection methods for investigating possible molecular heterogeneity and genetic polymorphism in human DNase I, in terms of both its antigenicity and enzymatic activity. One was an immunoblotting method using an antibody specific to DNase I following polyacrylamide gel isoelectric focusing (IEF-PAGE). The DNase I-specific antibody was raised in a rabbit using purified enzyme from human urine as the immunogen. DNase I in urine was found to exist in multiple forms with different pI values separable by IEF-PAGE within a pH range of 3.5-4.0. This method was able to detect as little as 0.1 micrograms of the purified DNase I and facilitated classification of desialylated urine samples from different individuals into several groups according to differences in DNase I isozyme patterns. About 0.5 ml of the original urine was sufficient for analysis of the isozyme patterns. The other method was the zymogram method, which had a high sensitivity and resolution almost identical to those of the immunoblotting method for analysis of DNase I patterns. It was easier to perform, more time-saving, and more useful since it did not require antibody specific to DNase I. These two methods should prove valuable for biochemical and genetic analysis of DNase I isozymes.

Antibodies↗

PubMed1994

[Etiologic classification of premature labor and its importance for prevention].

A retrospective analysis of 202 premature deliveries before 37 weeks was performed to identify major pathologies related to preterm delivery. The most frequent pathologies were premature rupture of membranes (32.4%), premature labour without recognisable aetiology (19.1%), hypertensive diseases in pregnancy (15.6%), multiple pregnancies (14.4%), malformations (9.8%) and bleeding in the 3rd trimester (6.4%). The majority of premature deliveries are related to 4 major pathogenetic disturbances: infection, problems of placentation, pathology of the foetus, pathology of the uterus. Each of these pathologies can lead to premature delivery via premature labour, premature rupture of membranes or termination of pregnancy for foetal or maternal pathology. In one third of premature labour, in another preterm premature rupture of membranes with labour after a variable latent period led to delivery, and in the remaining third, delivery was performed by a primary caesarean section or induction of labour for foetal or maternal pathology. Less than 25% cases were considered as failures of tocolytic treatment. Tocolytics, steroids or antibiotics, may help to improve the survival-rate in particular with very low birth-weight infants at less than 30 weeks gestation. A decrease in the overall rate of prematurity can be achieved only by a general improvement of the socio-economic working and living conditions of the female population, in particular of pregnant women.

Birth Weight↗

PubMed1995

Segmentation of mammograms using multiple linked self-organizing neural networks.

A possible first stage in the analysis of the mammographic scene is its segmentation into four major components: background (the nonbreast area), pectoral muscle, fibroglandular region (parenchyma), and adipose region. An algorithm has been developed for this task. It is based on the classification of a feature vector constructed from statistical measures of texture calculated at two window sizes. Separate self-organizing neural networks are trained on sample data taken from each of the four regions. The feature vectors from the entire mammogram are then classified with the trained networks linked via a decision logic. To overcome the variability of texture between mammograms the algorithm uses data from a mammogram to classify itself in a staged approach consisting of several binary decisions. The training regions for each successive stage are determined from geometric information produced by the previous stages. The dataset in the study consisted of thirty (fifteen pairs) digitized normal mammograms of variable radiographic appearance. As a measure of performance, the outlines of the parenchyma were compared to those drawn by a radiologist experienced in reading mammograms. Comparison of the areas and perimeters generated by the human and computer observers gives a relationship with correlation coefficients of 0.74 and 0.59 for each measure, respectively. The overlapping areas of the parenchymas segmented by the observers normalized by the combined area was also calculated for each case. The mean and standard deviation of this measure was 0.69 +/- 0.12.

Adipose Tissue↗

PubMed2003

Identification and classification of two-component systems that affect rpoS expression in Escherichia coli.

The rpoS-encoded sigmaS subunit of RNA polymerase regulates the expression of stationary phase and stress response genes in Escherichia coli. Recent study of our DNA microarray analysis suggested that the rpoS expression is affected by multiple two-component systems. In this study, we identified two-component-system mutants in which the rpoS expression increased. The regulatory manner of the systems on rpoS expression is suggested.

Bacterial Proteins↗