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81.
Since 2013, highly virulent porcine epidemic diarrhea virus has caused considerable economic losses in the United States. To determine the relation of US strains to those recently causing disease in Germany, we compared genomes and found that the strain from Germany is closely related to variants in the United States.  相似文献   
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83.
Tritiated 5alpha-androstane-3alpha,17beta-diol (3alpha-diol) and 5alpha-androstane-3beta,17beta-diol (3beta-diol) respectively were administered to patients with benign prostatic hypertrophy (bph) undergoing prostatectomy. In prostate and skeletal muscle homogenates and in plasma the total radioactivity content as well as the formation of metabolites were measured. Histological examination of each ectomized prostate was performed to evaluate the cellular composition of the tissue. After 3alpha-diol injection, a higher uptake of radioactivity in the prostate was obtained than after 3beta-diol. Within 30 min the 3alpha-isomer was very efficiently converted to 5alpha-DHT, while most of the 3beta-isomer remained unchanged. There was, however, also after administration of the 3beta-diol a substantial biconversion to 5alpha-DHT as has been confirmed by recrystallization to constant specific radioactivity. Only after 3beta-diol epiandrosterone was detected in small but significant amounts. 3alpha-diol administration resulted in distinct concentrations of 3beta-diol, whereas the conversion of 3beta-diol to the 3alpha-isomer was insignificant. When comparing the histological composition of the prostatic tissue with the accumulation of radioactivity and the formation of metabolites only a weak correlation between glandular structure and radioactivity uptake after 3alpha-diol administration could be revealed.  相似文献   
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In this two-part series on organ and tissue procurement in the acute care setting, the procurement problem, cost-benefit analysis, organizational development and framework, approach to surviving relatives, public attitudes, and brain death certification were discussed in part 1 (January 1990). Part 2 examines evaluation, selection, maintenance, and management of the organ-tissue donor. It concludes with a discussion of disease transmission, controversial issues, and financial considerations relevant to the procurement process in the acute care setting.  相似文献   
86.
We have developed a modified solvent/detergent (S/D) treatment to inactivate viruses in human plasma using 1% w/w final concentration of tri(n-butyl) phosphate (TNBP) and Triton X-100 and an incubation period of 4 h at 30 degrees C. The procedure inactivates > or = 10(6) chimpanzee-infectious doses (CID50) of HBV, > or = 10(5) CID50 of HCV, and > or = 10(6.2) tissue culture infectious doses (TCID50) of HIV. After virus inactivation, eleven plasma batches were lyophilized and 12 batches were deep-frozen until further use. The batches were characterized by extensive laboratory tests including measurement of clotting factors I-XIII, von Willebrand factor, plasminogen, inhibitors of blood coagulation and fibrinolysis, and other clinically important plasma proteins. All parameters were determined before and after S/D treatment. Twelve conventional single donor plasma units served as control. There were no marked losses of activities of clotting factors, antithrombin III, protein C, plasminogen, and C1-esterase inhibitor due to treatment. After the S/D step, the levels of these parameters were within the normal range in all batches. The same holds true for total protein, immunoglobulins, albumin, complement factors C3 and C4, haptoglobin, hemopexin, caeruloplasmin, alpha 1-antitrypsin, and pH. Protein S and alpha 2-antiplasmin activities decreased by about 50% and were frequently found to be slightly below the lower limit of the respective normal range after treatment. The interindividual variations of all proteins analysed were significantly lower than in the single donor plasma units. The S/D procedure did not lead to increases of markers indicating activation of hemostasis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
87.
During a mental rotation task of hands, participants mentally rotate their hand into the orientation of the shown hand. These mental movements are subject to the body's biomechanical constraints. In this study, we investigated whether the involvement of motor processes during the mental rotation process, as reflected in mu‐power desynchronization, is also influenced by one's movement capabilities. We performed an EEG study and used a delayed response mental rotation task of hands to examine the event‐related desynchronization differences between movements that are biomechanically easy and difficult to perform. Our results show an increase in event‐related desynchronization of the mu power for biomechanically easy compared to difficult‐to‐adopt postures. These findings provide further evidence for the notion that motor simulations can only be performed for movements that can already be performed overtly.  相似文献   
88.
The MRE11/RAD50/NIBRIN complex, a protein complex that repairs DNA double-strand breaks, could serve as an early marker for new lesions in pancreatic cancer. We determined the expression of MRE11, RAD50 and NIBRIN, and their possible prognostic value regarding survival.  相似文献   
89.
It is generally believed that the work of Bowlby and Robertson was new and decisive in changing the hospital conditions for young children. The fact that parents in the UK and other European countries can now visit their sick child at any time they wish or even room-in is attributed to an acquaintance with Bowlby's findings and Robertson's well-known films about the potentially detrimental effects of hospital stays for young children. In this paper we shall argue that this picture is incomplete and that, historically, things were rather more intricate. Bowlby and Robertson were neither the first nor the only researchers who tried to change hospital policies. Moreover, the older hospital policies were not uniformly bad. Long before Bowlby and Robertson began their plea for reforms, several individuals and hospitals had already introduced conditions that we now still regard as exemplary. The whole change towards more liberal, flexible, and humane practices in children's wards took place over several decades and was fuelled by both worried medical doctors, pressure groups of parents, sympathetic editors of medical journals, and emerging new research findings such as those provided by Bowlby and Robertson. In that societal debate, the voices of Bowlby and Robertson were influential but not necessarily new or decisive.  相似文献   
90.
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