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181.
The present study examined the comparability of 4 alternate forms of the Digit Symbol Substitution test and the Symbol Digit Modalities (written) test, including the original versions. Male contact-sport athletes (N=112) were assessed on 1 of the 4 forms of each test. Reasonable alternate form comparability was demonstrated through establishing normality of form distributions and conducting pairwise form comparisons of means, variability, and intraclass correlations. Nonetheless, alternate forms are likely an insufficient means of controlling practice in speeded measures at brief (1-2 weeks) retest intervals. Reliable change indices demonstrated that practice must be accounted for in individual retesting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
182.
Tissue culture cells' metabolism and viability are measured by the mitochondrial reduction rate of a yellow tetrazolium salt (MTT) to blue formazan crystalls in the MTT-bioassay. Thus the MTT-bioassay is a standardizable and reproducible bioassay for measuring cytotoxicity or cytostimulation. It is shown that the MTT-bioassay is also very suitable for determining bacterial cytotoxins using Escherichia coli's Shiga-like toxins as example. 177 strains ofE.coli, isolated from carcasses and organs of cattle, are classified biochemically and tested for cytotoxin production by means of the MTT-bioassay. One of these strains is recognized as producer of Shiga-like toxin 2. 4 Enterohemolysin-producing strains ofE.coli are cultivated from a feces sample of a diarrhoeic nubian ibex and identified as Shiga-like toxin 1 producers by help of the MTT-bioassay.  相似文献   
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BACKGROUND: A mechanical system for facilitating vascular anastomosis (end-to-side, end-to-end) is described that enables the rapid construction of nonpenetrated, compliant junctions. The instrument (United States Surgical One-Shot system) simultaneously applies either 10 or 12 nonpenetrating, arcuate-legged titanium clips to everted vessel or prosthetic conduit edges. METHODS AND RESULTS: The instrument has been tested in animals (jugular and femoral vein jump grafts in carotid and femoral arteries, interpositional grafts, 20 pigs) and human cadaveric constructs (saphenous veins to left anterior descending coronary arteries, 20 cases, 5 brachiocephalic access fistulas) as end-to-side constructs. Clipped constructs have equivalent or superior physical properties to control sutured constructs (6-0 polypropylene) as gauged by burst and tensile strength. All studies were performed under Food and Drug Administration Good Laboratory Practice standards, and the device has been approved for marketing by the Food and Drug Administration. CONCLUSIONS: The device enables rapid and reproducible vascular anastomotic constructs with vessels as small as 1.8 mm outer diameter. The constructs are flanged, interrupted, and nonpenetrated.  相似文献   
185.
A case series of eight cycles of in-vitro fertilization (IVF) in five women diagnosed with malignant disorders is presented. These patients chose to defer definitive treatment for a chance for preservation of potential fertility. The response of these patients to ovarian stimulation, and the outcome, was compared with 17 IVF cycles in 12 age-matched patients with isolated tubal infertility. An apparent adverse influence of malignant disease on the quality and behaviour of oocytes was observed. Despite a comparable total number of oocytes per cycle in the two groups, a significantly reduced percentage of mature oocytes was retrieved per cycle from patients with malignant diseases. The oocytes from patients with malignant disorders were of a poorer quality and exhibited a significantly impaired fertilization rate compared to the controls. We propose that neoplastic processes, irrespective of the site or cell of origin, may have a detrimental impact on the biology of oocytes, an effect akin to that seen on spermatozoa in men with certain malignancies.  相似文献   
186.
Responds to comments made by Holden and Blau (see record 2006-11202-017) on the current authors' original article (see record 2005-11115-005). The current authors suggest combining the complementary strengths of the community-based approaches identified by Holden and Blau (2006) and the evidence-based approaches discussed in their original article, rather than argue about the comparative limitations of each approach. Given that the contents of both systems of care and wraparound are free to vary with available services in the community, they suggest ensuring that those specific services are, in fact, interventions that have been tested and shown to work. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Beschreibung der Dämpfungsmessung zur Ermittlung interstitiell gelöster Elemente. Erläuterung der Ermittlung der Dämpfung durch Zeitmessung und Beschreibung des Versuchsaufbaus mit Zeitmeßeinrichtung und Datenverarbeitung. Darstellung der Versuchsergebnisse in Dämpfung-Temperatur-Kurven an Eisenlegierungen mit Stickstoff und Kohlenstoff und unterschiedlichen Mangangehalten.  相似文献   
189.
Carcinoma of the breast is the most frequent cause of death in women aged between approximately 38 and 50 years. At present, 1 out of 14 women in Germany and 1 out of 9 in America suffer from breast cancer within a life time. To date, modern methods of treatment and hormone therapy have only been able to increase long-term survival by about 12%. Trials have shown that early diagnosis alone has been able to increase survival from 20% to 50%. Early diagnosis proved to be most effective when clinical examination plus mammography in two planes was carried out annually. An increase in survival has been achieved in post-menopausal women as a result of screening. 22 percent of breast cancers were detected at a curable in situ stage by means of screening. Even after a limited screening program of 4 examination cycles the increase in survival rate over 15-20 years was significant.  相似文献   
190.
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