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981.
Boyce W. Thomas; O'Neill-Wagner Peggy; Price Cristofer S.; Haines Mark; Suomi Stephen J. 《Canadian Metallurgical Quarterly》1998,17(3):285
Environmental stressors and stable individual differences in human behavior have both been implicated etiologically in injuries. Because stress-related injuries are difficult to study experimentally in humans, the authors examined injury incidence in a troop of 21 male and 15 female free-ranging rhesus macaques (Macaca mulatta) before, during, and after a 6-month group confinement. Individual differences in behavioral inhibition to novelty were assessed, using multiple, quantified observations of behavior by 3 independent raters during 3 previous years. Incidence and severity of medically attended injuries were ascertained from veterinary records over a 2-year study period. A 5-fold increase in the incidence of injuries was documented during confinement stress, and an interaction was found between the stressor and behavioral inhibition in the prediction of injury incidence. Highly inhibited animals had significantly higher injury rates during confinement, compared with their uninhibited peers, but equal or lower rates in the low stress periods that preceded and followed confinement. Inhibited individuals appeared to have been specifically targeted for violence during the group stressor but were protected under normative, more predictable conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
982.
983.
984.
Nonenzymatic hydrolysis of phosphatidylcholine was investigated at several pH ranges in liposomes and mixed micelles. Phosphatidylcholine
was stable to hydrolysis for 140 hr at pH 4, 7 and 10, but slowly hydrolyzed at pH 1 with a half-time of 50 hr. We conclude
that phosphatidylcholine is not significantly degraded by hydrolysis under conditions typical for liposome preparation methods. 相似文献
985.
Ivermectin is not lethal to the adult worms of Onchocerca volvulus or to those of O. ochengi, a cattle parasite closely related to O. volvulus. Although ivermectin penetrates the nodules in which the adults of these nematodes live, it is not known what levels of the drug enter the worms. Adult male O. ochengi were incubated in [3H]ivermectin in a saturated solution of unlabelled ivermectin (11.44 microM), to measure uptake by the oral and transcuticular routes, and in [3H]inulin, to ascertain if oral ingestion occurs in vitro. Uptake of [3H]ivermectin was high [1040 disintegrations/min (d.p.m.) at 3 h, representing a mean total of 86 pmoles ivermectin/worm] and occurred predominantly by the transcuticular route. Viability of worms was not reduced by this exposure, and uptake continued for up to 12 h. Only low levels of [3H]inulin (four d.p.m.) were detected in worms, indicating that the gut is probably not functional in vitro. Scanning and transmission electron microscopy revealed that the epicuticle of both sexes had an irregular surface which was pitted with a honeycomb structure in males, and rough and abundantly folded in females. These structures greatly increased the absorptive surface of the worms. In conclusion, ivermectin is able to enter adult O. ochengi males at concentrations sufficient to kill non-filarial nematodes. 相似文献
986.
987.
PJ Borron EC Crouch JF Lewis JR Wright F Possmayer LJ Fraher 《Canadian Metallurgical Quarterly》1998,161(9):4599-4603
Components of the airspace-lining material may contribute to the local regulation of immune function within the lung. We report here that recombinant rat pulmonary surfactant-associated protein D (SP-D) inhibits the lectin- and anti-CD3-stimulated proliferation of human PBMCs. Inhibition was associated with a decreased production of IL-2, and the addition of human rIL-2 blocked the inhibitory action of SP-D. These effects were not inhibited by maltose, indicating that the inhibitory activity was not dependent upon the lectin activity of SP-D. Studies employing mutant SP-D lacking N-linked sugars or defective in multimerization further indicated that inhibition was not dependent upon cellular interactions with the N-linked oligosaccharide on SP-D or the oligomerization of trimeric SP-D subunits. Although a peptide containing an inverted DGR showed similar IL-2-dependent effects on anti-CD3-stimulated proliferation, deletion of the conserved DGRDGR sequence near the amino-terminal end of the collagen domain did not decrease the suppressive activity of SP-D. We hypothesize that SP-D can dampen lymphocyte responses to exogenous stimuli and protect the lung against collateral immune-mediated damage. 相似文献
988.
Checklists and other tools help doctors to use published evidence in clinical practice. Two other important sources of evidence, however, are the patient and his or her medical record. This series aims to advance the practice of evidence-based medicine by helping in redesign of medical records, drawing on insights from psychology, information design, and medical informatics; and by promoting changes analogous to those occurring in the medical literature. The four papers look at: the uses of medical records and importance of organising them so doctors can use the data they contain; different methods doctors use to search for data and how design of records can help or hinder these approaches; how we interpret data once found, and how record formatting assists this process; and the issues raised by computerisation of records. 相似文献
989.
Disinfectant surveys from responding members of the American Society of Postanesthesia Nurses were divided into two groups based on whether or not they considered themselves to be exposed to disinfectants in their work environment. Their survey responses were then compared with those obtained previously from members of the Society of Gastroenterology Nurses and Associates, Inc., who were regularly exposed to 2% alkaline glutaraldehyde in the work setting. There were significant differences among the groups in the percentage of respondents who reported having headaches, eye irritations, respiratory problems, shortness of breath, rashes, memory loss, mood swings, and fatigue. These findings support the association of these complaints with 2% alkaline glutaraldehyde exposure. In contrast, there were no significant differences among the groups in the percentage of respondents who reported having asthma, rhinitis, chest pain, nausea, diarrhea, muscle/joint pain, visual disturbances, or dermatitis. 相似文献
990.
Clinton O. Longenecker Jack L. Simonetti Mark Mulias 《Information Systems Management》1996,13(2):26-31
IS professionals can only dream of the days when technical brilliance alone was enough to ensure a successful career. Now business acumen and a strong understanding of customer expectations are vital to long-term career survival. Based on their study of 75 experienced IS professionals, the authors present guidelines for fostering the development of customer-oriented IS professionals. 相似文献