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941.
Whereas water loss in land living animals occurs continuously, water intake takes place discontinuously. At the normal operating set point of plasma osmolality, urine is more concentrated than plasma due to secretion of vasopressin. Thus animals operate around a state of mild dehydration. As water loss occurs, the severity of dehydration and thirst increase in intensity and at some point water intake occurs. Sufficient water is consumed to return plasma osmolality to the normal operating set point. Food intake and water balance are interdependent as food provides the osmoles which determine obligatory renal solute excretion. When dry food with the same osmotic content was substituted for canned food (water content 74%), dogs increased water intake from 24.2 +/- 4.3 to 62.2 +/- 8.8 ml/kg. Urine output and urine osmolality were unchanged, as under conditions of normal hydration, near maximal urine concentration is achieved. Changing water intake is the only available variable to maintain water balance. During water deprivation, the major renal mechanism appears to be natriuresis. In rehydration, satiety mechanisms ensure appropriate water intake and renal sodium conservation restores sodium balance. 相似文献
942.
S. Stegemann F. Leveiller D. Franchi H. de Jong H. Lindn 《European journal of pharmaceutical sciences》2007,31(5):249-261
Drug absorption, sufficient and reproducible bioavailability and/or pharmacokinetic profile in humans are recognized today as one of the major challenges in oral delivery of new drug substances. The issue arose especially when drug discovery and medicinal chemistry moved from wet chemistry to combinatorial chemistry and high throughput screening in the mid-1990s. Taking into account the drug product development times of 8–12 years, the apparent R&D productivity gap as determined by the number of products in late stage clinical development today, is the result of the drug discovery and formulation development in the late 1990s, which were the early and enthusiastic times of the combinatorial chemistry and high throughput screening. In parallel to implementation of these new technologies, tremendous knowledge has been accumulated on biological factors like transporters, metabolizing enzymes and efflux systems as well as on the physicochemical characteristics of the drug substances like crystal structures and salt formation impacting oral bioavailability. Research tools and technologies have been, are and will be developed to assess the impact of these factors on drug absorption for the new chemical entities.
The conference focused specifically on the impact of compounds with poor solubility on analytical evaluation, prediction of oral absorption, substance selection, material and formulation strategies and development. The existing tools and technologies, their potential utilization throughout the drug development process and the directions for further research to overcome existing gaps and influence these drug characteristics were discussed in detail. 相似文献
943.
对生长在合作地区的955名藏、汉族学生进行了个性特征及其影响因素的调查探讨。结果表明:本民族间男、女生E分比较,男生低于女生,显示女生性格较男生性格外向倾向性大。稳定性方面女生N分高于男生,即女生情绪一般不及男生稳定。此外与该地区藏汉族学生个性特征关系较为密切的因素是:兄弟姐妹数、父母亲文化程度、职业以及学前教育和智商。 相似文献
944.
945.
946.
目的:通过《医师法《、《医疗机构管理条例》和《医疗事故处理条例》的实施,明确了医疗机构及医务人员告知义务和患者知情同意和知情选择的重要性。方法:向每一位患者进行术前咨询详细介绍手术方法、材料选择、麻醉经过、恢复期的护理、并发症的预防和处理等使患者认识到自己的地位和相关的信息。结果:通过交谈,使医务人员和患者达成共识,从而消除了手术的顾虑,积极主动参与配合治疗,取得了双方满意的效果。讨论:强调预防为主,是医务人员自觉的接受法律的制约和监督,提高医德修养,履行告知说明义务的必要性和重要性,建立符合法律制度的医疗管理体系、规范医疗操作,遵循患者知情同意和知情选择这一受法律保护的基本权力。 相似文献
947.
高血压病合并脑梗死的动态血压特点 总被引:4,自引:0,他引:4
目的 :观察高血压病合并脑梗死患者的动态血压特点。方法 :对 70例高血压病合并脑梗死患者和 1 0 2例单纯高血压病患者进行 2 4h动态血压监测。结果 :84 %高血压病合并脑梗死患者血压昼夜节律消失 ,而单纯高血压病患者 5 8%消失 (P <0 .0 1 ) ;高血压病合并脑梗死组 85 %出现晨峰 ,而单纯高血压病组 5 5 %出现晨峰 (P <0 .0 1 )。结论 :血压的昼夜变化和晨峰与高血压病合并脑梗死密切相关。高血压病合并脑梗死患者晨峰明显增加 ,昼夜节律消失明显 相似文献
948.
949.
Sara Jo Nixon Austin L. Errico Oscar A. Parsons William R. Leber Cynthia J. Kelley 《Alcoholism, clinical and experimental research》1992,16(5):949-954
This study was conducted to determine whether alcoholic and control subjects respond differently to manipulations that either enhance personal involvement (PI) or reduce negative affect (R, relaxation) on tests of neuropsychological function. In Phase 1, 48 male alcoholics and 36 male control subjects completed neuropsychological tasks under standard instructional sets. In Phase 2, subjects completed equivalent forms of these tests under one of three randomly assigned conditions; the PI condition in which subjects were encouraged to identify specific ways of improving their performance, the R condition in which subjects participated in a short relaxation exercise designed to reduce anxiety, or a No Treatment (NT) condition in which no attempt to manipulate the subjects' involvement or affect was made. Alcoholics were inferior to controls in both Phase 1 and Phase 2 [Fs (1,82) > 5.03, ps < 0.03]. The experimental manipulation differentially affected measures of negative affect and effort in the predicted direction. There were no group x condition interactions. Alcoholic and control subjects responded comparably to the experimental manipulations. This investigation, in combination with others using related manipulations, reinforces the hypothesis that alcohol-related cognitives dysfunction reflects an underlying deficit in brain states. 相似文献
950.
Richard Lehman Frederick Andermann ré Olivier Prakash N. Tandon Luis F. Quesney Theodore B. Rasmussen 《Epilepsia》1994,35(6):1117-1124
Summary: It is not generally appreciated that intractable seizures involving the face area are amenable to surgical treatment. Twenty patients with onset of sensorimotor seizures in the face area of the pre- and postcentral gyri have been studied and surgically treated since 1948. Seizures started in the face, tongue, or throat, followed by diverse patterns depending on spread of seizure activity. Two patients had epilepsia partialis continua; 6 had either tonic or atonic drop attacks. All patients had pre- and postcentral face area resections, 12 in the dominant hemisphere. In addition, 3 had more extensive postcentral removal, 7 had temporal lobe, and 4 had small separate or contiguous frontal or parietal resection. Because the seizures were not sufficiently reduced by the first operation, 6 required reoperation; 4 of these patients had residual epileptiform activity on electrocorticogram (ECoG) after the first resection. Three patients had new neurologic signs that did not return to the preoperative level, but in 2 of them the deficit related mainly to higher resection in the central area. All but 2 of these 20 patients had at least moderate seizure reduction. Corticectomy can be performed for treatment of seizures arising in the lower central area and usually does not lead to significant permanent neurologic deficit. 相似文献