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991.
This study examines the effects of profound hypothermia on the blood-brain barrier (BBB) permeability in ethanol administrated rats. Vascular permeability to intravenously injected Evans blue (EB) was quantitatively examined in the brain regions of rats. Rats were treated with ethanol acute and chronically. Rectal temperature of rats was dropped into 20+/-1 degrees C during profound hypothermia. Mean arterial blood pressure in both acute and chronic ethanol treatments plus hypothermia significantly dropped into low levels as well as in hypothermia alone (P<0.01). Hypothermia led to a significant increase in the content of EB dye in the brain regions of rats (P<0.05). Both acute and chronic ethanol treatments plus hypothermia did not lead to a significant increase in the BBB permeability against intravenously injected EB dye. We conclude that ethanol intake protects the BBB against the effects of hypothermia.  相似文献   
992.
993.
994.
家兔死后眼玻璃体液锌、镍含量与 PMI关系的研究   总被引:6,自引:3,他引:3  
Gong ZQ  Xu XM  Zeng XB  Sun YG  Wang DW 《法医学杂志》2001,17(3):129-131
目的寻找一种精确推定PMI的方法。方法应用电感耦合等离子体质谱(ICP-MS),检测了家兔死后96小时内眼玻璃体液锌、镍元素含量,探讨其与PMI的相关性。结果家兔死后24h内眼玻璃体液锌、镍元素含量与PMI显著相关,可作为推定早期PMI的参考指标,其二项式回归方程分别为y=0.1404x2-1.3351x+3.8298(R2=0.9202)、y=0.0043x2-0.0596x+0.2665(R2=0.9103)。结论家兔眼玻璃体液中Zn、Ni元素含量变化是推定早期PMI的参考指标之一。  相似文献   
995.
996.
After Chile reformed its social security system in 1981, several other Latin American countries and certain Central and Eastern European (CEE) countries implemented the Chilean model, with some variations: either a single- or multitier system, or with a period of transition to take care of those in the labor force at the time of the change. The single-tier version consists of individual accounts in pension fund management companies. Multi-tier systems retain some form of public program and add mandatory individual accounts. Most of the CEE countries did not want to incur the high transition costs associated with the Chilean model. The switch to a market economy had already strained their economies. Also, the countries' desire to adopt the European Union's Euro as their currency--a move that required a specific debt ceiling--limited the amount of additional debt they could incur. This article describes the CEE reforms and makes some comparisons with the Latin American experience. Most of the CEE countries have chosen a mixed system and have restructured the pay-as-you-go (PAYGO) tier, while the Latin American countries have both single- and multi-tier systems. Some CEE countries have set up notional defined contribution (NDC) schemes for the PAYGO tier in which each insured person has a hypothetical account made up of all contributions during his or her working life. Survivors and disability programs in CEE have remained in the public tier, but in most of the Latin American programs the insured must purchase a separate insurance policy. Issues common to both regions include: Administrative costs are high and competition is keen, which has led to consolidation and mergers among the companies and a large market share controlled by a few companies. Benefits are proportionately lower for women than for men. A large, informal sector is not covered by social security. This sector is apparently much larger in Latin America than in the CEE countries. Issues that are unique to some of the CEE countries include: Individual accounts in Hungary and Poland have proved more attractive than originally anticipated. As a result, contributions to the public PAYGO system in Hungary and Poland fell short of expectations. In several countries, laws setting up the programs were enacted without all the details of providing benefits. For example, in some countries laws must now be drawn up for establishment of annuities because they do not yet exist. Setting up a coherent pension policy has been difficult in some countries because of frequent and significant changes in government. This situation has affected the progress of reform in various stages of development. In general, a definitive assessment of individual accounts in these countries will not be possible until a cohort of retirees has spent most of its career under the new system.  相似文献   
997.
Scheb  John M.  Lyons  William 《Political Behavior》2001,23(2):181-194
This article examines the mass public's perceptions of the factors that actually influence Supreme Court decisions as well those that ought to influence such decisions. We expect significant discrepancies between what the public believes ought to be the case and what it perceives to actually be the case with regard to Supreme Court decision making and that these discrepancies have a significant negative impact on the public's assessment of the Court. More specifically, we hypothesize that the public believes that political factors have more influence on the Court than ought to be the case and that the public perceives traditional legal factors to be less influential than they should be. We find that the expected discrepancies do exist and significantly detract from popular regard for the Court.  相似文献   
998.
A Linear Poisson Autoregressive Model: The Poisson AR(p) Model   总被引:1,自引:0,他引:1  
Time series of event counts are common in political scienceand other social science applications. Presently, there arefew satisfactory methods for identifying the dynamics in suchdata and accounting for the dynamic processes in event countsregression. We address this issue by building on earlier workfor persistent event counts in the Poisson exponentially weightedmoving-average model (PEWMA) of Brandt et al. (American Journalof Political Science 44(4):823–843, 2000). We developan alternative model for stationary mean reverting data, thePoisson autoregressive model of order p, or PAR(p) model. Issuesof identification and model selection are also considered. Wethen evaluate the properties of this model and present bothMonte Carlo evidence and applications to illustrate.  相似文献   
999.
The high rate of infant mortality among native peoples in the Aberdeen Service Area of the Indian Health Service (primarily North and South Dakota) prompted a multi-institutional study of this problem. The study investigators assumed that local coroners or medical examiners would be able to perform suitable death scene investigations. However, during the design portion of the study it became apparent that, with one exception, none of the participating Indian Nations had a death investigator or even a legal mandate to provide death investigation. To allow the study to go forward, and ultimately to better the community health within its service area, the Aberdeen Area Indian Health Service submitted a draft enabling coroner legislation/resolutions to the area tribes. By November of 1996, 6 of the 19 Indian Nations enacted enabling coroner legislation. To facilitate both the study and general death investigation within the area, the Aberdeen Area Indian Health Service since 1993 has held five 2-day death investigation training programs covering a variety of death investigation topics which were attended by 68 participants. Without further recognition of the need for tribal death investigation and additional funding, these gains in tribal death investigation will probably be transitory.  相似文献   
1000.
Previous case reports indicate that cocaine-associated rhabdomyolysis and excited delirium share many similar features, suggesting that they may be different stages of the same syndrome. We tested this hypothesis by comparing data from 150 cases of cocaine-associated rhabdomyolysis reported in the medical literature with data from an autopsy registry for 58 victims of fatal excited delirium and 125 victims of fatal acute cocaine toxicity. Patients with rhabdomyolysis are similar to victims of fatal excited delirium with regard to age; gender; race; route of cocaine administration; the experiencing of excitement, delirium, and hyperthermia; and the absence of seizures. Compared with victims of fatal acute cocaine toxicity, patients with rhabdomyolysis are different with regard to each of these variables. Compared with victims of fatal acute cocaine toxicity, both victims of rhabdomyolysis and fatal excited delirium are more likely to be black, male, and younger; to have administered cocaine by smoking or injection; and to have experienced excitement, delirium, and hyperthermia; they are also less likely to have had seizures. Because cocaine-associated rhabdomyolysis and excited delirium have similar clinical features and risk factors, occur in similar populations of drug users, and can be explained by the same pathophysiologic processes, we conclude that they are different stages of the same syndrome. It appears that this syndrome is caused by changes in dopamine processing induced by chronic and intense use of cocaine rather than by the acute toxic effects of the drug.  相似文献   
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