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At least 973 records · Page 54Linked to original sources
PubMed2002

[Port catheter fractures in 361 implanted port systems. Analysis of the causes--possible solutions--review of the literature].

INTRODUCTION: The use of a venous port-catheter-system is known as a relatively safe implant. Besides infections, the breakage of PIPS is the most common reason for explanation before term. The purpose of this study is to analyse port-related complications and to show ways of preventing them. METHOD: Between 1.1.1994 and 31.12.1999, 391 PIPS were implanted in the V. subclavia with the Seldinger technique at Surgical Clinic 1 of the University of Leipzig. Subsequently, 311 of them were followed up until 31.12.2000, with a mean observation time of 45 months. RESULTS: We registered 48 complications altogether (15.4% of 311), 21(6.7%) of which occurred immediately after implantation (up to 30 days postoperatively). These could be divided either into wound-healing disorders/pulmonary distress (4.5%, n = 14) or complications concerning the catheter systems (2.3%, n = 7). Long-term complications after 31 days were evident in 27 patients (8.7%), due either to infections (4.5%, n = 13) or catheter-associated problems (4.5%, n = 14). Catheter lesions occurred in nine cases (2.9% out of 311) at the point of entry into the musculus pectoralis, i.e., where the catheter had to change direction. Typically these were lengthways tears caused by the catheter. We observed one full breakage without dislocation, and two dislocated catheter fragments in the systemic circulation. We consider the change of direction to be responsible for wear on the silicon catheter. During implantation, extreme change of direction of the catheter should be avoided because this is where breakage happens. Catheter implantation by means of exposure of the vena basilica in the infraclavicular triangle is the method of choice.

Catheters, Indwelling↗
PubMed2000

[Prognostic assessment of resected lung cancer based on the new international staging system: analysis by histologic types].

The purpose of this study is to assess the validity of the new international staging system for lung cancer revised in 1997 and to clarify the prognostic value of histologic type. Of 1,042 patients with primary lung cancer who underwent resection from 1982 to 1995, 549 patients with adenocarcinoma (AD) and 363 with squamous cell carcinoma (SQ) were included in this study. Overall deaths including operative deaths were treated as the terminal event. For patients with AD, 5-year survival rates were 83% in T1N0M0, 70% in T2N0M0, 46% in T2N1M0, 45% in T3N0M0, 43% in T1N2M0, 32% in T1N1M0, 27% in T2N2M0, 25% in T3N1M0, and 10% in T3N2M0, respectively. For patients with SQ, 5-year survival rates were 80% in T1N0M0, 78% in T1N1M0, 67% in T1N2M0, 60% in T3N0M0, 56% in T2N0M0, 47% in T2N1M0, 36% in T3N1M0, 26% in T2N2M0, and 10% in T3N2M0, respectively. Survival of T1N2M0 was significantly better than that of T2N2M0 and similar to that of T3N0M0 and T2N1M0 both in AD and SQ. In AD survival was dominantly affected by N factor, while in SQ survival was strongly correlated with T factor. In conclusion, we propose that T1N1M0, T2N1M0, T3N0M0 and T1N2M0 should be classified as stage II and T3N2M0 be included into stage IIIB for AD. The TNM grouping for SQ is same as that for AD except setting T1N1M0 as stage IB and T2N0M0 as stage II.

Aged↗
PubMed1996

Hemodynamic system analysis of intraarterial microaxial pumps in vitro and in vivo.

Because of the lack of a sophisticated pump management system, the performance of the Hemopump in patients cannot assessed successfully. To clarify the interrelationship between an intravascular nonpulsatile pump and a pulsating ventricle, an in vitro study was set up under controlled conditions. Before these in vitro experiments, a series of in vivo experiments were performed in sheep using Hp31 cannulae. As anticipated, the resulting pulsatile pump flow was a function of the momentary pressure difference across the pump. This varying pump flow showed a significant flow loop hysteresis, indicating that the pressure difference across the pump is not the only parameter governing momentary pump flow of a rotary pump operating at constant speed in a pulsatile environment. Furthermore, flow in the Hp31 was significantly influenced by the inflow situation, blood supply, size of the ventricular cavity, and shape and position of the inflow cannula within the ventricle. Pulsatile flow conditions with good as well as impaired inflow into the pump were accordingly simulated in vitro to verify the in vivo measurements, to characterize the various inflow conditions, and to discuss methods of improved pump management. As a result of the in vivo and in vitro experiments, one can rely on the measurement of nonpulsatile in vitro flow and pressure differences across the pump to characterize the momentary pump flow for good inflow conditions into the pump. For these situations, the flow hysteresis produced, caused by fluid inertia within the pump and cannula, can be neglected. In contrast, for an impaired inflow situation, the calculated pump flow based on pressure difference measurements can be misleading. Consequently, an improved pump management system is required to adjust the pump speed, the pump performance, to any kind of impaired inflow.

Animals↗
PubMed2005

Membrane-based on-line optical analysis system for rapid detection of bacteria and spores.

We report here the adaptation of our electronic microchip technology towards the development of a new method for detecting and enumerating bacterial cells and spores. This new approach is based on the immuno-localization of bacterial spores captured on a membrane filter microchip placed within a flow cell. A combination of microfluidic, optical, and software components enables the integration of staining of the bacterial species with fully automated assays. The quantitation of the analyte signal is achieved through the measurement of a collective response or alternatively through the identification and counting of individual spores and particles. This new instrument displays outstanding analytical characteristics, and presents a limit of detection of approximately 500 spores when tested with Bacillus globigii (Bg), a commonly used simulant for Bacillus anthracis (Ba), with a total analysis time of only 5 min. Additionally, the system performed well when tested with real postal dust samples spiked with Bg in the presence of other common contaminants. This new approach is highly customizable towards a large number of relevant toxic chemicals, environmental factors, and analytes of relevance to clinical chemistry applications.

Bacillus↗
PubMedDate not supplied

Toward an automated analysis system for nuclear magnetic resonance imaging. I. Efficient pulse sequences for simultaneous T1-T2 imaging.

Simultaneous T1 and T2 images have been obtained using multiple-echo self-normalizing sequences. Differential T1 and T2 discrimination for two of these sequences, double saturation recovery and inversion-saturation recovery, have been explored in detail. The inversion-saturation recovery sequence exhibits T1 discrimination comparable to, and in many cases better than, that of optimal T1 weighted conventional pulse sequences, but is poor for T2 imaging. The double saturation recovery sequence yields comparable tissue discrimination for T1 and T2 imaging, but is poor compared to optimal T1 weighted and T2 weighted conventional pulse sequences. Simultaneous T1 and T2 images represent quantitative maps of intrinsic tissue properties, and hence form a natural basis for an automated image analysis and tissue classification system.

Brain↗
PubMed2006

[Film dose analysis system and its application in radiotherapy verification].

OBJECTIVE: To propose a new computer software-based medical image processing technique with high resolution digital scanner for radiotherapy verification. METHODS: Under the platform of Windows 2000, the software, programmed with Visual C++.NET, was developed according to modular design. All data of the films and the treatment planning system could be processed as images or dose curves for a robust result. RESULTS: Many functions such as data acquisition, automatic analysis and computation and image processing were integrated in the system. Both geometric and dosimetric errors could be calculated at the same time to verify the radiotherapy accuracy. CONCLUSION: This system has good accuracy and stability for cost-effective radiotherapy verification.

Film Dosimetry↗
PubMed2002

Validity and reliability of a voice-recognition game analysis system for field sports.

The purpose of this study was to assess the ability of observers to use voice-recognition analysis to accurately classify gait transitions and quantify gait durations typical of team games. Inter-rater and intra-rater reliability was also determined. Four males were filmed performing pre-determined gait protocols. each comprising different sequences of walking, jogging, running and sprinting. Two operators independently classified gait transitions and the time spent in each gait was determined by the voice recognition system. All gait modes as measured by trained observers demonstrated statistically significant correlations (p < 0.01) to pre-determined measurement criteria. The mean absolute error for all gait transitions was less than half a second (0.32-0.36 s) with the maximum percentage error being approximately 4% for the walk, jog and run gaits and 10% for sprinting. Gait classification error was low at 1.9%. The intra-rater and inter-rater reliability was consistently high ranging from r = 0.87 to 0.99. In conclusion, observers using voicerecognition software provided valid measures of time spent in each of the four gait categories with 90% or better accuracy achieved.

Adult↗
PubMed1993

On systems analysis in autism intervention programs.

Although intervention technology has grown substantially during the past quarter century, the design of intervention systems has not grown apace. This paper examines organizational arrangements that enhance and diminish treatment effectiveness and argues that defining, measuring, and manipulating systemic antecedent and consequent variables are as important as assessment and intervention on an individual client's behalf.

Autistic Disorder↗
PubMed2000

[Evaluation of epidemiologic surveillance systems: analysis of different approaches in a study in Ecuador].

Based on the experience of the assessment of public health surveillance systems, this paper explores the relationship between knowledge and action. Like research, evaluation is a cognitive process however oriented to a specific aim. Thus it is possible to compare the various approaches of evaluating these systems using the frame of paradigms in sciences (positivism, post positivism, critical theory and constructivism). In addition, evaluation aims to improve the functioning of the system, to introduce changes in it. The fourth generation evaluation, as it has been done in Ecuador, is an interesting way of acquiring understanding of the system while solving its malfunctionings. In this experience, the evaluator seeks the participation of the actors of the system at each steps of the evaluation process. He searches to involved them through three levels: intellectual, affective and ontological.

Centers for Disease Control and Prevention, U.S.↗
PubMed2003

[Clinical application for reference strand mediated conformation analysis system in HLA-A genotyping].

OBJECTIVE: To establish and stabilize a new HLA typing strategy, reference strand mediated conformation analysis (RSCA), and to conform its advantages by using HLA-A as target gene. METHODS: 20 standard DNA samples from international RSCA cooperative team were used to establish and stabilize RSCA. 84 DNA samples of related hematopoietic stem cell transplant donor-recipients were extracted from peripheral blood cells. HLA-A loci were typed both by RSCA and PCR-SSP. RESULTS: RSCA results of 20 standard samples were identical to those of international RSCA cooperative team, and the accuracy and replication rate were both 100%. Among the 84 samples, 82/84 (97.6%) cases could be designated definitely, and 33/84 (39%) cases could be typed to allelic level. In addition, 2/84 (2.4%) cases could not be detected by RSCA for their poor PCR results. 20 samples were randomly selected to identify the replication rate of RSCA, and the results demonstrated that the replication rate was 100%. Among the PCR-SSP typing results, there were about 10% samples needed to be typed for 1 - 3 times to confirm their types. CONCLUSION: RSCA has some advantages compared with the PCR-SSP typing method, which are high resolution, high sensitivity, high accuracy, high replication, capability to find new alleles, high throughput, low cost and suitability for unrelated hematopoietic stem cell transplant donor-recipient HLA typing. But there are still some defects in this new strategy, which are time-consuming for only one sample a time and higher DNA quality requirement. In addition, RSCA database needs to be further improved.

Adolescent↗
PubMed2003

Development of an affordable data collection, reporting, and analysis system.

Available professionally designed systems for recording, storing, retrieving, and analyzing patient data (such as treatments delivered, laboratory and pulmonary function test results, ventilator settings, and patient assessments) are prohibitively expensive to many hospitals and clinics. At Tufts-New England Medical Center we designed and implemented a computerized patient data management system that uses relatively inexpensive "personal digital assistants" and inexpensive, commonly-available software. Compared to the pen-and-paper flow sheet system we previously used, our computerized system saves time and money, is accurate and user-friendly, and allows data retrieval and analysis that can improve clinical practice and efficiency. We believe our experience could benefit other institutions.

Academic Medical Centers↗
PubMedDate not supplied

Toward an automated analysis system for nuclear magnetic resonance imaging. II. Initial segmentation algorithm.

Image segmentation algorithms based on hierarchical clustering have been developed for analysis of T1 and T2 nuclear magnetic resonance images. Application of these algorithms to simultaneous T1-T2 images of healthy volunteers extracted fundamental tissue types in the brain. These algorithms also were used both to identify the extent of the region of involvement of a subject with a history of a grade 3 astrocytoma of the right frontal lobe of the brain, and to characterize the tissue within the region of involvement. These results suggest that a simple segmentation algorithm can produce reasonable clustering of tissue types within the brain.

Biometry↗