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91.
A new composite flow curve statement is presented, which allows good approximation of the flow curve and is suitable for numeric simulations. Without restrictions, it holds over the entire range of validity of a flow curve as a function of plastic strain, plastic strain rate and temperature. Simultaneously, it can be used for any material so that it is well suited for material databases. The number of coefficients used is higher than in other flow curve statements; however, the coefficients are calculated more easily and partially by automatic procedures. The described composite statement can be integrated so that it can be employed in analytical calculations, e.g. of force and power requirements.  相似文献   
92.
We report the ability of azithromycin in combination with quinine to eliminate the Babesia infection in a native Taiwanese woman. Failure of elimination of the babesial infection was observed two weeks after treating with standard regimen of oral quinine plus intravenous clindamycin for a 10-day course of therapy. Azithromycin in place of clindamycin was administered for another 10-day course of therapy two months following initial treatment. Clearance of Babesia parasites was observed and verified by hamster inoculation. These results suggest that azithromycin plus quinine should be considered as an alternative therapy for human babesiosis, especially in the failure of treatment with standard regimens.  相似文献   
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This study describes the frequency of reporting vocal problems among a random sample of elementary and high school teachers (n = 554) compared to individuals working in other occupations (n = 220). Teachers were more likely to define themselves as ever having a voice problem (32% versus. 1%, p < .05); having a tired, weak, or effortful voice (p < .05 each); and having a higher frequency of symptoms of physical discomfort with speaking (p < .05). They also were more likely to perceive that their voice problem negatively affected current job performance (p < .05) and limited options regarding change in work (p < .05). About 20% of teachers but only 4% of nonteachers had missed work due to their voice. These findings suggest that teachers are at high-risk for disability from voice disorders and that this health problem may have significant work-related and economic effects.  相似文献   
96.
The development of Schwann cells, the myelin-forming glial cells of the vertebrate peripheral nervous system, involves a neonatal phase of proliferation in which cells migrate along and segregate newly formed axons. Withdrawal from the cell cycle, around postnatal days 2-4 in rodents, initiates terminal differentiation to the myelinating state. During this time, Schwann cell number is subject to stringent regulation such that within the first postnatal week, axons and myelinating Schwann cells attain the one-to-one relationship characteristic of the mature nerve. The mechanisms that underly this developmental control remain largely undefined. In this report, we examine the role of apoptosis in the determination of postnatal Schwann cell number. We find that Schwann cells isolated from postnatal day 3 rat sciatic nerve undergo apoptosis in vitro upon serum withdrawal and that Schwann cell death can be prevented by beta forms of neuregulin (NRG-beta) but not by fibroblast growth factor 2 or platelet-derived growth factors AA and BB. This NRG-beta-mediated Schwann cell survival is apparently transduced through an ErbB2/ErbB3 receptor heterodimer. We also provide evidence that postnatal Schwann cells undergo developmentally regulated apoptosis in vivo. Together with other recent findings, these results suggest that Schwann cell apoptosis may play an important role in peripheral nerve development and that Schwann cell survival may be regulated by access to axonally derived NRG.  相似文献   
97.
The Sheltered Care Environment Scale (SCES) was developed primarily to measure social climate as an attribute of a setting. As such, the SCES was designed to maximize differences between facilities and minimize differences among individuals within a setting. However, G. C. Smith and S. K. Whitbourne (see record 1990-27263-001) assessed the validity of the SCES as a measure of individual differences in perceptions of a shared environment. Moreover, they redefined the content coverage of 2 of the SCES subscales (Independence and Physical Comfort) to encompass attributes the SCES is not intended to measure. In general, preliminary evidence indicates that the SCES subscales provide reasonably reliable and valid indices of the social climate of group residential facilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Translated from Fiziko-Khimicheskaya Mekhanika Materialov, Vol. 24, No. 2, pp. 77–82, March–April, 1988.  相似文献   
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The presence of orbital lymphatics in the primate model is demonstrated using light and electron microscopic enzyme histochemistry. In addition, strictly morphological definitions of lymphatics, such as discontinuous basal lamina, thin and irregular walls, anchoring filaments, and attenuated endothelial cell cytoplasm, were applied. This study confirmed the presence of conjunctival lymphatics reported by others. It also clearly demonstrated the presence of orbital arachnoid and lacrimal gland lymphatics that have not been previously described. A few areas of the extraocular muscles and connective tissue at the orbital apex also showed evidence of the presence of lymphatic vessels. Additional work is needed to define the nature and extent of orbital lymphatics as well as their connection to the extraorbital lymphatic system.  相似文献   
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