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101.
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
102.
目的 了解上海地区学生午餐营养及供应链状况,为改善学生午餐营养状况,保障食品供应安全提供参考。方法 分析上海市学生午餐的营养、卫生、供应链、加工工艺等状况,采用定期抽检的方法,应用SNHAS对营养素、食品安全、感官进行综合评价。结果 各单位样本综合评价均合格,其中热量、蛋白质、脂肪均能达到或超过DRIs供给量的要求,但矿物质中Ca(仅为AI的32%)、视黄醇当量(仅为AI的57%)供给量较低。对供应链及卫生状况的分析表明,大型企业对各个环节控制严格,产品质量较好,但也存在保存时间过长等问题。结论 应进一步完善供应体系,建立高效的质量控制体系,推广营养配膳系统。 相似文献
103.
Improving the safety of patient care is an issue which affects health systems in both developed and developing countries. To co-ordinate and accelerate improvements in patient safety, the World Health Organization (WHO) has supported the creation of the World Alliance for Patient Safety which was launched in October 2004. The six action areas of the Alliance are Patients for Patient Safety, Taxonomy, Research, Solutions for Patient Safety, Reporting and Learning, and a biennial Global Patient Safety Challenge. The first Challenge covering 2005-2006 was launched in October 2005 under the banner 'Clean Care is Safer Care'. The Challenge addresses health care-associated infection, a major, patient safety problem affecting hundreds of millions of people worldwide. 相似文献
104.
The effect of the novel 1,4-dihydronaphthyridine Ca2+ channel inhibitor Goe 5438 (CI-951) on voluntary ethanol consumption was examined in selectively bred alcohol-preferring (P) rats in a free choice two bottle preference test versus water. Intraperitoneally injected Goe 5438 dose-dependently (5, 10 or 20 µmol/kg, twice daily) inhibited ethanol and increased water intake over the 24 h period (injection day). The drug decreased ethanol preference, originally above 90%, by 6%, 19% and 45% at respective doses, on the injection day. That inhibitory effect of the highest dose of Goe 5438 on ethanol preference remained significant also on days 2 and 3 after injections (–51% and –18%, respectively). Goe 5438, in the highest dose, also tended to decrease granulated chow consumption during the injection day only. To further test whether the inhibition of ethanol preference is secondary to decrease in reinforcing properties of ethanol and not due to interference with satiety mechanisms, we compared the effect of two higher doses (10 and 20 µmol/kg, intraperitoneally, twice daily) of Goe 5438 on spontaneous preference for a non-caloric 0.04% saccharin solution in Sprague-Dawley rats. We observed a dose-dependent suppression of preference (by 44% and 58%, respectively) during the injection day, but not the subsequent 24 h period. However, Goe 5438 also significantly alleviated food pellet intake on the injection day. In conclusion, Goe 5438 produces potent and long-lasting inhibition of voluntary ethanol consumption, which may be secondary to attenuation of reinforcing properties of ethanol. Additionally, this particular Ca2+ channel inhibitor appears to have mild anorectic properties which may be conducive to acute suppression of alcohol intake. 相似文献
105.
PCM van de Kerkhof 《Journal of the European Academy of Dermatology and Venereology》2006,20(6):639-650
Psoriasis is a chronic, incurable disease that frequently requires long-term treatment. Although many patients benefit from effective traditional systemic therapies, namely methotrexate, cyclosporin, retinoids and fumaric acid esters, and some patients achieve long-term disease control, unrestricted long-term administration is not recommended due to the potential for cumulative toxicity. In order to diminish the risk of toxicity, physicians have adopted various treatment approaches (e.g. rotational, sequential, intermittent, and combination). However, these approaches may not provide continuous disease control or a stable treatment regimen. The recent advent of targeted biological therapeutics such as etanercept, infliximab, adalimumab, alefacept and efalizumab may offer physicians and their patients treatment options with improved safety profiles that may permit continuous disease control. 相似文献
106.
Bayesian decision theoretic approaches (BDTAs) have been widely studied in the literature as tools for designing and conducting phase II clinical trials. However, full Bayesian approaches that consider multiple endpoints are lacking. Since the monitoring of toxicity is a major goal of phase II trials, we propose an adaptive group sequential design using a BDTA, which characterizes efficacy and toxicity as correlated bivariate binary endpoints. We allow trade‐off between the two endpoints. Interim evaluations are conducted group sequentially, but the number of interim looks and the size of each group are chosen adaptively based on current observations. We utilize a loss function consisting of two components: the loss associated with accruing, treating, and monitoring patients, and the loss associated with making incorrect decisions. The performance of our Bayesian modeling, and the operating characteristics of decision rules under a wide range of loss function parameters are evaluated using seven scenarios in a simulation study. Our method is illustrated in the context of a single‐arm phase II trial of bevacizumab, gemcitabine, and oxaliplatin in patients with metastatic pancreatic adenocarcinoma. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
107.
Efficacy and safety of transcranial magnetic stimulation in the acute treatment of major depression: a multisite randomized controlled trial. 总被引:6,自引:0,他引:6
John P O'Reardon H Brent Solvason Philip G Janicak Shirlene Sampson Keith E Isenberg Ziad Nahas William M McDonald David Avery Paul B Fitzgerald Colleen Loo Mark A Demitrack Mark S George Harold A Sackeim 《Neuropsychopharmacology》2007,62(11):1208-1216
BACKGROUND: We tested whether transcranial magnetic stimulation (TMS) over the left dorsolateral prefrontal cortex (DLPFC) is effective and safe in the acute treatment of major depression. METHODS: In a double-blind, multisite study, 301 medication-free patients with major depression who had not benefited from prior treatment were randomized to active (n = 155) or sham TMS (n = 146) conditions. Sessions were conducted five times per week with TMS at 10 pulses/sec, 120% of motor threshold, 3000 pulses/session, for 4-6 weeks. Primary outcome was the symptom score change as assessed at week 4 with the Montgomery-Asberg Depression Rating Scale (MADRS). Secondary outcomes included changes on the 17- and 24-item Hamilton Depression Rating Scale (HAMD) and response and remission rates with the MADRS and HAMD. RESULTS: Active TMS was significantly superior to sham TMS on the MADRS at week 4 (with a post hoc correction for inequality in symptom severity between groups at baseline), as well as on the HAMD17 and HAMD24 scales at weeks 4 and 6. Response rates were significantly higher with active TMS on all three scales at weeks 4 and 6. Remission rates were approximately twofold higher with active TMS at week 6 and significant on the MADRS and HAMD24 scales (but not the HAMD17 scale). Active TMS was well tolerated with a low dropout rate for adverse events (4.5%) that were generally mild and limited to transient scalp discomfort or pain. CONCLUSIONS: Transcranial magnetic stimulation was effective in treating major depression with minimal side effects reported. It offers clinicians a novel alternative for the treatment of this disorder. 相似文献
108.
Introduction Medication errors are a preventable cause of patient injury. In May 2003, as a result of a joint initiative by the Royal College
of Anaesthetists, the Association of Anaesthetists of Great Britain and Ireland, the Intercollegiate Faculty of Accident and
Emergency Medicine and the Intensive Care Society, a new colour code chart for syringe labelling was introduced. The introduction
of the new system has not been uniform in the Irish Republic with no national guidelines or time scale in place.
Methods A questionnaire was administered to doctors working in Anaesthesia in two Dublin teaching hospitals.
Results As much as 23% had administered an incorrect medication and 53% admitted to a near miss as a result of the introduction of
the new label.
Discussion Future action should focus on practical, common sense interventions including techniques such as those that reduce reliance
on memory, standardization, the use of protocols and checklists, and the elimination of look-alike products. 相似文献
109.
基于RFID的病人用药安全管理新技术探讨 总被引:1,自引:0,他引:1
目前,我国在病人用药安全方面存在的主要问题是:病人本人用药安全意识淡漠、政府和卫生机构管理乏力、医院内部管理不规范、缺乏合适且有效的高新技术的支持。针对这些问题,提出基于先进的RFID技术的病人用药安全管理的新技术和解决方案,从而提高病患在用药过程中的安全系数,辅助相关医疗管理人员对药物进行准确有效的使用,防止用药安全事故的发生。 相似文献
110.
D. Trainer P.R. Pehrsson D.B. Haytowitz J.M. Holden K.M. Phillips A.S. Rasor N.A. Conley 《Journal of food composition and analysis》2010,23(8):843-851
The National Food and Nutrient Analysis Program (NFNAP) was implemented in 1997 to update and improve the quality of food composition data maintained by the United States Department of Agriculture (USDA). NFNAP was designed to sample and analyze frequently consumed foods in the U.S. food supply using statistically rigorous sampling plans, established sample handling procedures, and qualified analytical laboratories. Methods for careful handling of food samples from acquisition to analysis were developed to ensure the integrity of the samples and subsequent generation of accurate nutrient values. The infrastructure of NFNAP, under which over 1500 foods have been sampled, mandates tested sample handling protocols for a wide variety of foods. The majority of these foods were categorized into several major areas: (1) frozen foods; (2) fresh produce and/or highly perishable foods requiring refrigeration; (3) fast foods and prepared foods; (4) shelf-stable foods; (5) specialized study and non-retail (point of production) foods; and (6) foods from remote areas (e.g. American Indian reservations). This paper describes the sample handling approaches, from the collection and receipt of the food items to the preparation of the analytical samples, with emphasis on the strategies developed for those foods. It provides a foundation for developing sample handling protocols of foods to be analyzed under NFNAP and for other researchers working on similar projects. 相似文献