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At least 19 recordsLinked to original sources
PubMed1979

National Cooperative Crohn's Disease Study: study design and conduct of the study.

The design and execution of the National Cooperative Crohn's Disease Study are described in this paper. The Study incorporated several noteworthy features developed to meet specific demands of the disease and its therapy. A standard clinical grading system, the Crohn's Disease Activity Index (CDAI) was developed to allow uniform decentralized clinical evaluation and decision-making throughout the 5 yr of the study. All three drugs in widespread clinical use in Crohn's disease were studied both for suppressive and prophylactic efficacy and for toxicity. The study employed a scheme for double-blind evaluation of patient progress which allowed adjustment of prednisone dose according to the degree of illness and ensured continuous monitoring for serious toxicity of any study drug. Results were analyzed primarily by ranking the clinical outcome of every patient according to a uniform and detailed scheme and applying Wilcoxon nonparametric statistics. Outcome was also analyzed by life-table methods. Eleven hundred nineteen patients were entered and 604 patients were randomized at 14 study centers during the 5-yr duration of the study. Twenty patients were eliminated from analysis as not meeting diagnostic criteria for Crohn's disease, and another 15 patients were eliminated as not meeting other preestablished criteria for analysis. Nine percent of randomized patients, equally distributed in the four treatment groups, withdrew as noncompliant. Ninety percent of patients completed all or all but one protocol-specified visits, and 95% completed the final radiologic and sigmoidoscopic evaluation.

Azathioprine↗
PubMed1977

Esophageal cancer studies in the Caspian littoral of Iran: results of population studies--a prodrome. Joint Iran-International Agency for Research on Cancer Study Group.

Epidemiologic studies were undertaken on the Caspian littoral of Iran to investigate the geographic distribution of factors that might underlie the signal differences in incidence of cancer of the esophagus. In zones of contrasting incidence and sex ratio, information was obtained on food intake, smoking and drinking patterns (including tea), other personal habits, occupation, economic and agricultural practices, and methods of food storage preservation, and preparation. The diet in the highest incidence area was markedly restricted to bread and tea. The poor quality of the diet itself was thought to have a role in the increased risk of developing esophageal cancer. The use of opium and sesame oil, consumption of sheep's milk and yogurt, the chewing of nass (confined to men), and the use of dyes (confined to women) were also more prevalent in the high incidence areas. Typical dietary items were analyzed for the polycyclic aromatic hydrocarbons, volatile nitrosamines, aflatoxins, nitrates, and nitrites. The results showed no unusual levels of any of the carcinogens tested or geographic differences.

Agriculture↗
PubMed1976

Puerperal weck clip sterilization: study II (second study of two consecutive studies).

Forty-five puerperal inverted V Weck clip applications have been completed with either the Samuel's or (modified) Weck pistol-grip applicator. Of the 45 applications, 31 have been followed for 25 to 36 months (69%), 12 have been followed for 13 to 25 months (27%), and 2 have been followed for 9 to 12 months (4%). The failure rate thus far is 2.2%. No mechanical difficulties were encountered with the Samuel's or the (modified) Weck pistol-grip applicator. Reversibility has been observed in one interval patient, while pre-admission evaluation of a puerperal patient suggests postremoval tubal patency.

Evaluation Studies as Topic↗
PubMed1976

Puerperal Weck clip sterilization: study I (first study of two consecutive studies).

One hundred and four puerperal applications have been performed using the (original) Weck pistol-grip applicator and applying the large Weck clip in the inverted V configuration. Follow-up varied from 37 to 42 months. The corrected failure rate was 8.7%. Mechanical difficulties were encountered with the jaws and metal sleeve of the (original) Weck pistol-grip applicator. Recovered clip configuration and tubal tissue histology are presented. Histologic changes suggest possible reversibility.

Animals↗
PubMed1975

[Studies on the 14C-15N-acetamide turnover in sheep. 2. Studies on 15N turnover and comparative studies on the 14C turnover].

Three fistula sheep with average weights of 52.2 kgs were given 37.9 g of 15N and 14C labelled acetamide (= 1.09 mg 15N' and 0,95 mCi14C) which were administered directly through the fistula. The half-life period of 15N retention in the ruminal fluid (TCE soluble portion) was found to be 4 hrs. 18 hrs after 15N administration increasing amounts of 15N were carried back to the rumen by way of the rumino-hepatic circulation. The 15N concentration in the blood (TCE soluble portion) rapidly increased up to a peak value and, from 3 hrs after isotope administration, the 15N concentration was found to decline continuously, with a slight discontinuation at about the 10th hr of experiment. The rate of 15N incorporation into the protein fraction (TEC soluble portion) of the blood was delayed by 4 hrs, relative to the rate of 15N incorporation into ruminal proteins. An average of 43.1% of the administered amount of 15N was excreted in the urine within 7 days. Up to the 4th day of experiment the half-life period of urinary 15N excretion was 19 hrs. An average of 15% of the administered total amount of 15N was excreted in the faeces. In this process, the peak values in both TCE fractions were observed to occur on the 2nd day of experiment. The proportion of isotope in the TCE soluble fraction was found to increase continuously compared with the total amount of the isotope excreted in the faeces. Isotope concentrations between 0.03 and 0.13 atom% of surplus 15N were found in organ and muscle tissues of a sheep that had been slaughtered 7 days after administration of the isotope. The results obtained are discussed on the basis of comparisons made with the analogous behaviour of 14C activity.

Acetamides↗
PubMed2026

Evaluating Wearable Devices for Remote Monitoring in Psychosis: Pilot Study Nested Within the CONNECT Cohort Study.

BACKGROUND: Digital remote monitoring technologies, including smartphones and wearables, offer promising avenues for early detection of psychosis relapse. However, selecting devices that are acceptable to participants and produce high-quality data remains challenging. OBJECTIVE: The aim of this nested pilot study was to assess the acceptability and data quality of 3 commercially available wearable devices in people with psychosis recruited to the CONNECT cohort study. METHODS: Participants recruited to the CONNECT study before July 31, 2024, were included in the pilot study and selected 1 of 3 wearable devices: a Fitbit Charge 5, Samsung Galaxy Watch 5, or Apple Watch SE. Baseline demographics were compared between device groups. Acceptability of devices to participants was assessed through a Wearable Device Satisfaction Questionnaire after 3 months of use, with the proportion of positive responses to each question calculated and compared. Data completeness was also assessed by calculating the number (and percentage) of valid days of step count, heart rate, and sleep data, and comparing between groups. Data quality was assessed through summarizing the amount of troubleshooting required, additional metrics available from the wearables, and continuity of data completeness by calculating the proportion of participants with at least 3 days of heart rate data per week for the first 20 weeks of follow-up. Predefined criteria were used to determine the next steps for the wider CONNECT study: if one device was superior, this would be selected; if none were found to be superior and the Fitbit was found to be noninferior, then Fitbit would be retained. RESULTS: Of the first 107 participants recruited to CONNECT, 105 were included in the pilot study evaluation. The Samsung Galaxy Watch was selected most frequently by participants (46/105, 43.8%), followed by the Apple Watch (27/105, 25.7%), and Fitbit Charge (23/105, 21.9%). Differences in participant demographics were observed across device groups. Self-reported acceptability after use did not differ substantially between devices. However, in terms of data completeness, the median proportion of valid heart rate data days was significantly lower for Samsung Galaxy (median 31.2%, IQR 8.5%-46.0%) compared to Fitbit (median 80.1%, IQR 26.7%-95.0%; P=.003) and Apple Watch (median 49.3%, IQR 21.5%-86.0%; P=.02). There was no significant difference between Fitbit and Apple Watch. Similar patterns were observed for step count and sleep data. The Samsung Galaxy Watch required more frequent troubleshooting for data flow issues and lacked additional physiological metrics, available from the other devices. CONCLUSIONS: Due to comparatively lower data quality and technical performance, the Samsung Galaxy Watch was discontinued for use in the subsequent phase of the CONNECT study. The study highlights the importance of incorporating nested evaluations of devices in long-term research.

Humans↗
PubMed1992

[Multicenter study on the treatment and outcome of patients admitted to intensive care units in Italy. Presentation of the research project and the study protocol. GiViTI (Gruppo Italiano per la Valutazione degli interventi in Terapia Intensiva)].

Although Intensive Care Units (ICU) are present in most of the Italian Hospitals for acute patients, the heterogeneity of the patients case-mix and the large variation in structural, organizational and staffing arrangements have limited the feasibility and precision of evaluation studies aimed at assessing the quality of health care delivered and its impact on patients outcomes. To our knowledge there has been no nationwide study aimed at assessing the quality and effectiveness of the delivered care in samples of ICUs and patients that are representative of the source populations. To study the effects of variations in health care practices on the outcome of the patients admitted in ICU, we designed a multicentric observational study involving 120 ICUs within the country. The present study is the first part of a project involving a network of Intensive Care Units gathered under the name of GiViTI-Italian Group for the Evaluation of the Interventions in Intensive Care-that is representative of the national Italian reality in the field. The idea of a large collaborative group acting in the field of Intensive Care stands in line with several quality, effectiveness and resource utilization studies that are ongoing in other European countries and is also the result of a series of smaller-scale experiences carried out by other Italian groups eventually emboied in the GiViTI project. In the framework of the ongoing long term, multisite, and multidisciplinary project, the present study calls for the recruitment of all consecutive patients seen at the participant centers during a two months period.(ABSTRACT TRUNCATED AT 250 WORDS)

Critical Care↗
PubMed1992

Short-term intraindividual variability in hemostasis factors. The ARIC Study. Atherosclerosis Risk in Communities Intraindividual Variability Study.

Recent epidemiologic studies found that there is a strong association of hemostatic factors with ischemic heart disease. The Atherosclerosis Risk in Communities (ARIC) Intraindividual Variability (IIV) Study was conducted to estimate the various components of variation in hemostasis factors measured in the ARIC Study and to estimate the measures of repeatability of these factors. A total of 39 subjects (16 men, 23 women) were studied. Each had blood collected three times, with a 1- to 2-week interval between each visit. The contributions of between-person variability, within-person (biologic) variability, and processing and assay variability were estimated. Then the reliability coefficient R was estimated as the proportion of total variance accounted for by between-person variance. The reliability coefficient can be interpreted as the correlation between measures made at repeat visits. Among the various analytes, the reliability coefficients were quite high for activated partial thromboplastin time and plasma factor VIII (R = 0.92, 0.86, respectively). Low repeatability was obtained for antithrombin III activity and protein C (R = 0.42, 0.56, respectively). The lack of repeatability for these variables derives mostly from the processing (field center and laboratory) variation. Other analytes--fibrinogen, plasma factor VII, and von Willebrand factor--were intermediate in repeatability. In comparing the analyte-specific high-level to low-level groups, no substantial difference of within-person plus method coefficient of variation between the two groups was found for any analyte except for factor VIII, whereas the corresponding variance components for most analytes were higher for the higher analyte level. Reliability coefficients from this ARIC IIV study are generally higher than those found in other studies, and this is related to the relative variations in populations studied and to the time between measurements.

Antithrombin III↗
PubMed1976

Spirometric comparison of carbuterol and isoproterenol aerosol therapy in bronchial asthma. A double blind, matched-pair study of 28 adults and a double blind crossover study of 18 children.

Two adrenergic aerosols were compared in a double blind, matched-pair study of 6 months' duration in 28 adult patients with chronic bronchial asthma, and in a double blind, crossover, short-term study in 18 children with severe asthma. In the adult study, one member of each pair was given either 150 mug of isoproterenol or 200 mug of carbuterol 4 times per day, by inhalation, for 6 months. In the childhood study, 18 children, 6 to 12 years of age, with moderate to severe asthma were studied in a double blind, crossover therapeutic trial in which high or low doses of aerosolized carbuterol or isoproterenol were given 4 times daily for 5 days each. Treatment results were evaluated by measuring forced vital capacity, 1-sec forced expiratory volume, and maximal mid-expiratory flow (FEF25-75%) at regulat intervals before and after administration of the respective test drugs. In the adult study, there was a significant difference between carbuterol and isoproterenol for forced vital capacity (P less than 0.02), for 1-sec forced expiratory volume (P less than 0.02), and for FEF25-75% (P less than 0.01) in favor of carbuterol. In the pediatric study, the difference between carbuterol and isoproterenol was significant (P less than 0.05) only for the FEF25-75% on the fifth day of treatment with the high dose administration of carbuterol. There was no associated toxicity of either drug with respect to electrocardiogram, blood chemistry, or subjective complaints. Tachyphylaxis (tolerance with time) to isoproterenol appeared to develop in one patient.

Adrenergic beta-Agonists↗
PubMed1992

The World Health Organization study on health effects of exposure to cadmium: morbidity studies.

Studies according to the protocol of the WHO Regional Office for Europe were performed in Germany, the Netherlands and Belgium. Pilot studies were performed in Czechoslovakia, Hungary and Poland. The results of the Belgian study are described elsewhere; some striking results of the other studies are reported here. The highest levels of cadmium in blood (Cd-B) were reported in a cadmium-polluted area in Hungary, the lowest in a non-polluted urban area. In Poland, levels were enhanced in polluted and non-polluted areas. The highest levels of cadmium in urine (Cd-U) were found in Hungary, the lowest in the Netherlands. In nearly all the studies significant increases in both Cd-B and Cd-U were found in cadmium-polluted areas. The picture is less clear with regard to the biological effect parameters. The renal parameters were sometimes significantly enhanced for the polluted areas, but sometimes the opposite was reported. Because of the many confounding variables, stratification at least by smoking behaviour, sex and age is necessary if firm conclusions are to be reached. A better approach, however, is to use multivariate regression analysis. This technique allowed the calculation of the relation between Cd-U and age in the German and Dutch studies, and between Cd-U and age in the German and Dutch studies, and between Cd-U and NAG, AAP, Alb-U and Creat-S levels.

Adult↗
PubMedDate not supplied

[A method for studying social security records in epidemiology. Use in a study on the prognosis of chronic bronchitis (author's transl)].

A method is presented to study, in an epidemiological research, the social security records. This study is based upon records of workers affiliated to the french social security general system. To obtain data which may be compared, it was necessary to take the legislation as a basis; this legislation gives the data which must be in the records. A study of laws and rules has been done to find out these data in the medical record and in the administrative one. A questionnaire is presented. This basic questionnaire should be modified according to the precise objectives of each study and to the characteristics of the population sample. To illustrate this method, some results of a study of chronic bronchitis risk factors are presented in the second part. These results concern 950 men, born in France, aged 30 to 59 in 1960 an still alive in 1972. The study of the long reductions of the ability to work, happened from 1960 to 1971, confirm the disabling character of the group "chronic bronchitis, asthma, emphysema, respiratory insufficiency" which follows immediately cardiovascular and rheumatic diseases. The total number of beneficiaries of the social security is already very important and the whole population will be soon concerned. The use of the social security records as data source could give very interesting informations about morbidity. So, it is possible to study representative samples of the general population or of some particular groups, which has up to now, been done only in a slight extent.

Adult↗
PubMed1978

The population study of women in Göteborg 1974--1975--the second phase of a longitudinal study. General design, purpose and sampling results.

A study of a population sample of women in Göteborg aged 38--60 years was carried out in 1968--1969. This population sample has been re-studied during the years 1974--1975. Altogether 1302 women participated in this second study, which means 89.1% of those studied in 1968--1969 and 80.3% of those initially sampled. Twenty-six women had died during the interval between the two studies, more than half of them from neoplastic disease. Information is given about those who had moved or were inaccessible at the time of the second study or who refused to participate. The performance of the examination is described and research projects are outlined.

Adult↗
PubMed1977

Clinical and serologic study of four smallpox vaccines comparing variations of dose and route of administration. Basic study and laboratory standardization.

The present four-center collaborative study was undertaken in an attempt to define the best vaccine and/or vaccination procedure for use in areas of the world that are free of smallpox. The study was designed to compare the effect of different vaccinial strains, viral concentrations, and routes of administration on the morbidity and antibody response associated with primary vaccination and standard challenge revaccination. Primary vaccinations were performed on 1,585 children; 49.6% of the children were vaccinated by the percutaneous route, and 50.4% received vaccine subcutaneously. The overall age and sex distributions of percutaneous and subcutaneous vaccinees were comparable, but there were marked differences in participants among the four study centers. Vaccines in Kentucky had a greater mean age; the greatest number of Negroid children were enrolled in St. Louis, and more of them were vaccinated by the subcutaneous route; and the dropout rate was much greater in San Diego and Colorado. An analysis of comparative interlaboratory serologic procedures with the use of 20 coded duplicate samples of serum revealed good agreement in the hemagglutination-inhibition test; results of neutralization tests had greater variability of mean titers. On duplicate samples of serum from study participants there was generally good correlation between each of the four study centers and the Center for Disease Control's reference laboratory in titers of hemagglutination-inhibiting antibody. In contrast, 38% of the neutralization titers determined at the four study centers were greater than or equal to 0.67 log10 higher than the respective titers noted at the Center for Disease Control.

Black or African American↗
PubMed1975

Hemispheric specialization in normal man studied by bilateral measurements of the regional cerebral blood flow. A study with the 133-Xe inhalation technique.

Changes of regional cerebral blood flow (rCBF) during mental activation have so far only been studied unilaterally by means of the intracarotid 133Xe injection technique. In the present study bilateral rCBF measurements were made by the 133Xe inhalation technique during mental activities supposed to engage the hemispheres selectively. The study was carried out on 24 normal right-handed male volunteers by the short 133Xe inhalation method. Fourteen scintilation detectors were placed in parallel overcorresponding regions of the two hemispheres. Four rCBF measurements were made on each subject during three randomized conditions: (1) Rest (two studies); (2) Verbal test (Miller Analogy Test), and (3) Spatial test (Street). The recordings were separated by at least one hour to avoid contamination from previous measurement. The answers to the problems were given either by raising the fingers of the left hand (Verbal test) or after the study (Spatial test). In order to investigate the effects of increased motivation 12 of the subjects were promised an extra money reward in addition to the basic payment, if they performed above a certain level on the tests. Small but statistically significant differences between the average hemisphere flows were recorded during the two tests. In the highest motivated (paid) group the verbal test increased the flow in the left hemisphere by 16 per cent while the right-sided increase was significantly smaller, 13 per cent (P less than 0-001). The corresponding figures for the spatial test were: left 7 per cent, right 10 per cent (P less than 0-01). The same tendencies were seen in the less motivated group although the hemisphere differences were smaller and statistically not significant. Analysis of the regional results showed that the largest interhemispheric differences (about 5 per cent) were seen in occipital and parietal regions during the verbal test and in frontal and parietal regions during the spatial test. It is concluded that bilateral measurements of rCBF can be used with advantage in the study of lateralization of mental functions in the human brain.

Adolescent↗