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81.
Aquaporins (AQPs) are water channels that mediate the efficient movement of water across the membrane. Among different AQPs, AQP4 is the predominant water channel in the brain and is thought to play a significant role in the physiopathology of brain edema. Brain edema is a major clinical problem since it largely accounts for the cause of death in patients suffering from traumatic brain injury or cerebrovascular accidents. In this review, we have tried to summarize comprehensive information about the pathological events conducting to brain edema. In addition, we also have summarized active investigation in the field of AQPs and cerebral edema to find plausible explanations and to deduce potential future directions for the treatment of this clinical condition.  相似文献   
82.
Reliable and comparable analysis of risks to health is key for preventing disease and injury. Causal attribution of morbidity and mortality to risk factors has traditionally been conducted in the context of methodological traditions of individual risk factors, often in a limited number of settings, restricting comparability.  相似文献   
83.
84.
Ferrant  A; Cogneau  M; Leners  N; Jamar  F; Martiat  P; Michaux  JL 《Blood》1993,81(12):3435-3439
The effectiveness of bone marrow transplantation (BMT) for malignant blood diseases remains limited by the inability of the preparative regimen to eliminate the disease without causing toxicity to normal organs. We have used 52Fe to deliver radiotherapy selectively to the BM. Fourteen patients with hematologic malignancies received 52Fe before a conventional BMT conditioning regimen. The median 52Fe dose was 58 mCi (range, 32 to 85 mCi). As evaluated by quantitative scanning, the median percentage of 52Fe taken up by the BM was 82% (range, 36% to 90%). This resulted in a median radiation-absorbed dose to the BM of 632 rad (range, 151 to 1,144 rad). The median uptake of 52Fe by the liver was 18% (range, 10% to 64%) and the median radiation- absorbed dose to the liver was 239 rad (range, 82 to 526 rad). The median whole body radiation-absorbed dose was 46 rad (range, 22 to 68 rad). No untoward effects were noted after the injections of 52Fe. The patients recovered hematopoiesis without toxicity in excess of that expected with conventional conditioning alone. The median follow-up was 8 months and three patients have relapsed. 52Fe should provide a way to boost the radiation dose to marrow-based diseases before marrow transplantation without increasing toxicity.  相似文献   
85.
目的:调查兰州部队辖区黄河流域老年痴呆及认知障碍的患病率并分析其危险因素。方法:应用《长谷川智力量表》(22~30.5分为轻度异常,10.5~21.5分为痴呆前期,≤10分为痴呆期)和《临床记忆量表》(≤80分为异常),对黄河流域11个地区51个干休所16538人群中2944名60岁以上人员进行调查。采用挨家挨户一对一的的方法开展调查检测,只有2个量表评分均为异常才列为病例组,同时对一般情况、驻地海拔高度、家族遗传史、既往病史、生活习惯等5个方面30个危险因素进行调查,并应用SPSS10.0软件包将调查结果进行多元回归分析。结果:2944名受试者全部完成测试进入结果分析。①老年痴呆的患病率分别为痴呆0.71%,痴呆前期2.11%,轻度异常28.46%,总患病率为31.28%。②多元回归分析结果:脑萎缩(t=-6.304)、重大生活事件(t=-5.328)、高龄(t=-5.415)、无喝茶嗜好(t=-3.802)、脑梗死(t=-3.343)、女性(t=-2.604)、冠心病(t=2.496)、低文化程度(t=1.973)、职业(t=1.965)、高海拔地区(t=1.957)与老年痴呆相关(P均<0.05)。结论:①黄河流域老年痴呆及认知障碍发生与脑萎缩、重大生活事件、高龄、无喝茶嗜好、脑梗死、女性、冠心病、低文化程度、职业、高海拔地区等10种危险因素有关。②结果显示痴呆发病率较低,而痴呆前期及轻度异常发病率较高,所以应重视痴呆前期及轻度异常患者的干预治疗。  相似文献   
86.
Doppman  JL; Brennan  MF; Dunnick  NR; Kahn  CR; Gorden  P 《Radiology》1981,138(3):557-562
The palpation and enucleation of occult insulinomas (less than 15 mm) can be a difficult surgical problem even with good arteriographic localization. In the authors' limited experience, confirmation of arteriographic findings by pancreatic venous sampling provided little additional localizing information. However, if arteriography is negative or equivocal, venous sampling can indicate the segment of pancreas to be "blindly" resected if the adenoma is not palpable. Venous sampling may be misleading in polyendocrine syndromes because of the frequency of multiple adenomas and variable hormone production.  相似文献   
87.
We have evaluated the potential neuroprotectant activity of minocycline in an animal model of Parkinson's disease induced by intranigral injection of lipopolysaccharide. Minocycline treatment was very effective in protecting number of nigral dopaminergic neurons and loss of reactive astrocytes at 7 days postlesion. Evaluation of microglia revealed that minocycline treatment highly prevented the lipopolysaccharide-induced activation of reactive microglia as visualized by OX-42 and OX-6 immunohistochemistry. Short-term RT-PCR analysis demonstrated that minocycline partially prevented the lipopolysaccharide-induced increases of mRNA levels for interleukin-1alpha and tumor necrosis factor-alpha. In addition, lipopolysaccharide highly induced protein nitration as seen by 3-nitrotyrosine immunoreactivity in the ventral mesencephalon. Minocycline treatment strongly diminished the extent of 3-nitrotyrosine immunoreactivity. We also found a direct correlation between location of IgG immunoreactivity-a marker of blood-brain barrier disruption-and neurodegenerative processes including death of nigral dopaminergic cells and reactive astrocytes. There was also a precise spatial correlation between disruption of blood-brain barrier and 3-nitrotyrosine immunoreactivity. We discuss potential involvement of lipopolysaccharide-induced formation of peroxynitrites and cytokines in the pathological events in substantia nigra in response to inflammation. If inflammation is proved to be involved in the ethiopathology of Parkinson's disease, our data support the use of minocycline in parkinsonian patients.  相似文献   
88.
L1 is a cell adhesion molecule implicated in the formation of neural circuits and synaptic plasticity. We have examined the sequence and time-frame in which modifications in the synaptic expression of L1 occur in the piriform cortex and hippocampus in the course of rule learning of an olfactory discrimination task. Rats were trained to choose the correct odour in a pair to be rewarded with drinking water. Such training requires 6-8 days on average before rats reach maximal performance. We observed a learning-induced L1 up-regulation that occurred at an early training stage in the piriform cortex but only after rule-learning establishment in the hippocampus. We suggest that the dynamics of L1 up-regulation may reflect the functional role of these brain regions in olfactory rule learning.  相似文献   
89.
ObjectiveTo estimate health care systems'' value in treating major illnesses for each US state and identify system characteristics associated with value.Data sourcesAnnual condition‐specific death and incidence estimates for each US state from the Global Burden Disease 2019 Study and annual health care spending per person for each state from the National Health Expenditure Accounts.Study designUsing non‐linear meta‐stochastic frontier analysis, mortality incidence ratios for 136 major treatable illnesses were regressed separately on per capita health care spending and key covariates such as age, obesity, smoking, and educational attainment. State‐ and year‐specific inefficiency estimates were extracted for each health condition and combined to create a single estimate of health care delivery system value for each US state for each year, 1991–2014. The association between changes in health care value and changes in 23 key health care system characteristics and state policies was measured.Data collection/extraction methodsNot applicable.Principal findingsUS state with relatively high spending per person or relatively poor health‐outcomes were shown to have low health care delivery system value. New Jersey, Maryland, Florida, Arizona, and New York attained the highest value scores in 2014 (81 [95% uncertainty interval 72‐88], 80 [72‐87], 80 [71‐86], 77 [69‐84], and 77 [66‐85], respectively), after controlling for health care spending, age, obesity, smoking, physical activity, race, and educational attainment. Greater market concentration of hospitals and of insurers were associated with worse health care value (p‐value ranging from <0.01 to 0.02). Higher hospital geographic density and use were also associated with worse health care value (p‐value ranging from 0.03 to 0.05). Enrollment in Medicare Advantage HMOs was associated with better value, as was more generous Medicaid income eligibility (p‐value 0.04 and 0.01).ConclusionsSubstantial variation in the value of health care exists across states. Key health system characteristics such as market concentration and provider density were associated with value.  相似文献   
90.

Background

In 2002, the World Health Organization published a health system performance ranking for 191 member countries. The ranking was based on five indicators, with fixed weights common to all countries.

Methods

We investigate the feasibility and desirability of using mathematical programming techniques that allow weights to vary across countries to reflect their varying circumstances and objectives.

Results

By global distributional measures, scores and ranks are found to be not very sensitive to changes in weights, although differences can be large for individual countries.

Conclusions

Building the flexibility of variable weights into calculation of the performance index is a useful way to respond to the debates and criticisms appearing since publication of the ranking.  相似文献   
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