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31.
Abstract: To perform the first experimental tests for validation of a new gear unit concept, the pump chamber, diaphragm, and pusher plate design of an orthotopic electromechanical total artificial heart (TAH) (Helmholtz Labtype) was manufactured. In its early stage of development, it provides some of the most important features of the conceptual final artificial heart. The new gear unit transforms a uniform unidirectional rotational motor movement into translatory pusher plate movements, with resting phase in the end–diastolic position, and the angled pump chamber orientation determines the available space for the motor and gear unit. Furthermore, this labtype provides flexibility with regard to use of different types of structural parts for experimental investigations. The first in vitro test results, obtained with specially designed circulatory mockloops that simulate physiological preload and afterload conditions, are presented. They comprise pressure and flow generation, motor performance, efficiency, and energy consumption. The results prove the feasability of the new gear unit concept for an electromechanical artificial heart and allow a reliable determination of the necessary performance of the future brushless DC motor for the first in vivo TAH model. 相似文献
32.
Patch testing was carried out in 851 atopic patients; 181 atopic dermatitis (AD) patients were additionally tested with 50% dilutions of the test substances. The occurrence of allergic and irritant reactions was frequent, being 57% and 33% for AD patients aged 28-41 years and 19-27 years, respectively. Among age-matched allergic rhinitis (AR)/allergic conjunctivitis (AC) or asthma (A) patients, the number of allergic reactions varied from 25 to 30%, and for irritant reactions was 24%. In all groups, nickel, fragrance-mix, balsam of Peru and neomycin were the commonest allergens. Contact allergy to ingredients of topical medicaments was common among AD patients and patients with severe and long-lasting dermatitis were most frequently sensitized. However, sensitivity to multiple substances was not common among those patients. The number of irritant reactions was considerable, but 50% dilution of the test substances did not solve the problem. 相似文献
33.
Oguzkan Sürücü Ulrich Sure Sabine Gaetzner Sonja Stahl Ludwig Benes Helmut Bertalanffy Ute Felbor 《Child's nervous system》2006,22(11):1461-1464
Introduction and background A 3-year-old Bosnian girl with a large symptomatic brainstem and multiple supratentorial cavernous angiomas, who underwent neurosurgical treatment, is presented. As multiple cavernomas are more common in familial cases, genetic analyses and neuroradiological imaging were performed in the patient and her parents to see whether there was any evidence for inheritance. This information is important for genetic counseling and provision of medical care for at-risk relatives. Currently, no recommendation is available on how to manage these cases.Results Genetic analyses demonstrated a novel CCM1 frameshift mutation (c.1683_1684insA; p.V562SfsX6) in the child and the asymptomatic 27-year-old mother. Sensitive gradient-echo magnetic resonance imaging of the mother revealed multiple supratentorial lesions, whereas analogous imaging of the father showed no pathological findings.Conclusion This case exemplifies that seemingly sporadic cases with multiple lesions might well be hereditary and that presymptomatic genetic testing of family members may identify relatives for whom clinical and neuroradiological monitoring is indicated. 相似文献
34.
Corinna S. Bowser Jean Kaye Rauno O. Joks Cascy-Arnoux Charlot H. Jack Moallem 《Pediatric allergy and immunology》2007,18(4):298-303
Elevated serum immunoglobulin E (IgE) and increased prevalence of atopy is reported in patients infected with human immunodeficiency virus (HIV). The elevated serum IgE may be attributed to polyclonal stimulation of B cells or IgE production against allergens, viruses, fungi and bacteria. This study investigates the prevalence of atopy in perinatally HIV-infected children, and the relationships between serum IgE (and other serum immunoglobulins) with atopy, CD4+ cell count and HIV-disease stage. Serum immunoglobulin levels, epicutaneous skin test for common aeroallergens, clinical Centers for Disease Control and Prevention (CDC) classification, CD4+ cell counts and allergy history were extracted from the charts of perinatally HIV-infected children on highly active antiretroviral therapy. The prevalence of atopy (52%) and the pattern of aeroallergen sensitivity were comparable with the US pediatric population. Serum IgE levels did not correlate with clinical disease stage. However, in non-atopic patients, serum IgE levels increased with disease progression (p = 0.02). There was an inverse relationship between the prevalence of elevated serum IgE levels and atopy with progression of disease (p = 0.019). Serum IgE did not correlate with atopy, CD4+ cell count, or duration of HIV infection or levels of serum immunoglobulins. This is the first study to show no increased prevalence of atopy in perinatally HIV-infected children compared with the general population. In advanced stages of HIV, elevated serum IgE may be specific for antigens other than those known as allergens. 相似文献
35.
A total of 240 survivors of one or more myocardial infarctions were consecutively admitted to perform supine exercise radionuclide ventriculography. Within 3 years after the test, 22 died; this group was compared to an age-matched control group of 22 survivors for left and right ventricular function during rest, exercise, and simultaneously assessed exercise performance as well as ECG variables. Evaluation of 3-year survival by linear discriminant analysis revealed an accuracy of 82% for discriminant models using ECG and exercise performance variables. Implementation of resting left ventricular ejection fraction and change of right ventricular ejection fraction during exercise, as well as scintigraphic presence or absence of dyskinesia, improved the accuracy of the model to 91% of correctly classified patients. 相似文献
36.
This study sought to measure the effect of pulmonary function testing (PFT) data on the decisions made by generalist physicians
in the management of chronic obstructive pulmonary disease (COPD). 148 physicians were randomly assigned to two groups, both
of which were asked to manage two identical fictitious but representative cases of COPD, which included history, physical,
x-ray, and laboratory results. The experimental group received PFT results in addition. No significant difference was noted
between the two groups in management based on availability of PFT data. The optimum utility of PFT data in the management
of COPD may be exaggerated and has yet to be determined.
Received from the Department of Medicine, Division of General Internal Medicine, Medical College of Wisconsin, Milwaukee,
Wisconsin.
Presented at the Annual Scientific Meeting of the American College of Chest Physicians, October 28, 1992, Chicago, Illinois. 相似文献
37.
V. van Casteren P. Leurquin A. Bartelds F. Gurtner V. Massari S. Maurice-Tison A.T. Vega R. Mak 《European journal of epidemiology》1993,9(2):169-175
This study describes a p. year international data collection on the demand pattern for HIV-antibody tests in general practice recorded by 6 sentinel networks in 5 European countries. The purpose of the recording was to evaluate the use of HIV-antibody testing by general practitioners and the demand for testing among the general population. Sentinel networks of general practitioners are a possible and available instrument for monitoring the perception of the HIV-test, and indirectly of the threat of the HIV-epidemic by the public and by the general practitioners (GPs). Differences were found between the countries in the frequency of testing, the person asking the test and the reason for testing. Possible explanatory factors, such as differences in the routine testing of specific groups, differences in the training and in the role of the GP, differences in the characteristics of prevention policy, are discussed. The European comparison also offers the opportunity to reflect on common medical practice in dealing with demands for HIV-tests. 相似文献
38.
39.
Bipolar affective disorder. II. EEG, neuropsychological, and clinical correlates of CT abnormality 总被引:1,自引:0,他引:1
M J Dewan C V Haldipur M F Boucher T Ramachandran L F Major 《Acta psychiatrica Scandinavica》1988,77(6):677-682
Since the clinical significance of CT abnormalities found in bipolar patients remains obscure, we studied 26 DSM-III bipolar patients who had specific CT abnormalities (third ventricle enlargement, and hyperdensity of the caudate, thalamus, anterior frontal white matter, and right temporal lobe) on numerous parameters such as EEG, the Halstead-Reitan Neuropsychological Battery, premorbid personality adjustment, family history of affective disorder, positive and negative symptoms, employment history, and response to lithium carbonate treatment. None of these measures could differentiate between the CT abnormal and CT normal subgroups. The implications of these findings are discussed. 相似文献
40.
In 1396 consecutively patch tested patients 18 (1.3%) reacted to Kathon CG. Relevance was established in 4 of the 18 patients. The frequency of positive reactions to Kathon CG in eczema patients seems to have been stable in Denmark during the period 1983 to 1988. 相似文献