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991.
All district health authorities are obliged to use resources most efficiently. One approach to increasing efficiency is to identify measures which allow service levels, in terms of patients treated and standards of care, to be maintained at a lower cost. This could be achieved by maintaining service levels with fewer hospital beds. Reducing lengths of stay by removing organizational delays and expansions of day-case care, are policies which can increase patient caseload per bed. This paper puts forward an approach for estimating the resources released by such policies and assesses the savings achieved by realizing efficiency gains identified in a previous study by Beech et al. (1987). That study identified significant potential for maintaining services with fewer beds, with the expansion of day-case care being a key mechanism. However this paper concludes that when services are maintained with fewer beds, the vast majority of hospital costs remain fixed. It also reaches the alarming conclusion that as a vehicle for reducing costs, day-case care is much less effective than previous studies have implied. However, increasing hospital throughput per bed does release capacity to treat more patients. The proposed reforms of the NHS (Secretaries of State, 1989) envisage an internal market for health care, allowing hospitals to enter into contracts with purchasers of health care. The approach to costing described in this paper is applicable to assessing the increased costs associated with such developments. These extra costs can then be compared with expected income. 相似文献
992.
D. F. Wozniak J. W. Olney L. Kettinger III M. Price J. P. Miller 《Psychopharmacology》1990,101(1):47-56
Several experiments were conducted to study the effects of the noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist, MK-801, on learning and memory in the rat. Rats displayed impaired performance on several sensorimotor tests and appeared grossly intoxicated when treated IP with 0.2 mg/kg MK-801, but not when treated with lower doses (0.05 or 0.1 mg/kg). Postacquisition performance on two spatial learning tasks involving working memory protocols (reinforced alternation and radial arm maze) was impaired by MK-801 at intoxicating doses (0.2 mg/kg) but not at lower doses (0.05 or 0.1 mg/kg). Using a position habit reversal task, we found that rats could learn to reverse a position habit while under the influence of a nonintoxicating dose of MK-801 (0.1 mg/kg), but when tested on the following day performed as if they did not recall what they had learned. Thus, acute administration of a nonintoxicating dose of MK-801 disrupts the retention of new information learned under the influence of the drug but does not interfere with the performance of tasks that are well learned before the drug is administered. Whether the performance deficits on the spatial learning tasks observed only following intoxicating doses of MK-801 reflect an effect on memory is not clear. 相似文献
993.
A Simple Rheological Method for the in Vitro Assessment of Mucin-Polymer Bioadhesive Bond Strength 总被引:2,自引:0,他引:2
A simple viscometric method was used to quantify mucin-polymer bioadhesive bond strength. Viscosities of 15% (w/v) porcine gastric mucin dispersions in 0.1 N HC1 (pH 1) or 0.1 N acetate buffer (pH 5.5) were measured with a Brookfield viscometer in the absence (m) or presence (t) of selected neutral, anionic, and cationic polymers (0.1–2.5%, w/v). Viscosity components of bioadhesion (1%) were calculated from the equation, t = m + p + b, where p is the viscosity of corresponding pure polymer solution as measured by an Ostwald viscometer. The forces of bioadhesion (F) were calculated from the equation, F = b, where is the rate of shear/sec. b's and F's for polyelectrolytes, e.g., polyacrylic acid, cationic gelatin, and chitosan were always higher in acetate buffer than in HC1. Validity of the technique and the effect of ionic charge, polymer conformation, and rate of shear on b and F are discussed, as is a comparison of this method to other methods for evaluating bioadhesive materials. 相似文献
994.
Helmut Kreppel Franz -Xaver Reichl Ladislaus Szinicz Burckhard Fichtl Wolfgang Forth 《Archives of toxicology》1990,64(5):387-392
The efficacy ofdl-dimercaptopropanol (British Anti-Lewisite, BAL),dl-dimercaptopropanesulfonate (DMPS), and meso-dimercaptosuccinic acid (DMS A) was compared in reducing the acute As2O3 toxicity in mice. Mice were treated with a single equimolar dose of a dithiol compound (0.7 mmol/kg i.p.) 0.5 or 30 min after the s.c. injection of various doses of As2O3. Both DMPS and DMSA were significantly (p<0.05) more effective in mice treated 0.5 min after the poisoning if compared to BAL on an equimolar level. The highest potency ratio (PR) (LD50 with treatment/LD5o without treatment) was found in animals injected with DMSA (PR=8.6). The corresponding value for DMPS was 4.2, and for BAL 2.1, respectively. In animals treated 30 min after poisoning the efficacy of DMPS (PR = 2.6) was similar to the efficacy of DMSA 2.4, both being only slightly superior to BAL 2.O. DMPS and DMSA were found to be much less toxic than BAL. The LD50 of arsenic was 0.057 mmol/kg. The efficacy of BAL, DMPS, and DMSA in reducing the tissue content of arsenic following acute As2O3 poisoning was investigated in mice (n=6/group) and guinea pigs (n=3-4/group). The animals were injected s.c. with 0.043 mmol/kg As2O3 (containing a tracer dose of74As(III)). Thirty minutes later the antidotes were administered A were more effective in reducing the arsenic content of tissues than BAL. Moreover, BAL caused accumulation of the toxicant in the brain. It is concluded that the recommendation of BAL as drug of choice in acute arsenic poisoning needs to be carefully re-evaluated. 相似文献
995.
冷冻浓缩腹水回输在治疗顽固性肝硬化腹水中的应用 总被引:4,自引:0,他引:4
目的 探讨冷冻浓缩腹水回输治疗顽固性肝硬化腹水的疗效。方法 采用透析机对32例顽固性肝硬化腹水患者的腹水进行超滤浓缩,置-18℃环境中冷冻2~3天,37℃温育溶解后静脉回输。结果 冷冻浓缩腹水回输前后,血清总蛋白为(59.1±5.6)g/L和(66.3±4.7)g/L,白/球比值为0.8±0.3和1.1±0.5,腹水总蛋白为(15.2±6.8)g/L和(55.6±8.4)g/L;腹围为(91.3±9.5)cm和(80.8±9.2)cm,腹压为(3.5±0.43)kPa和(2.4±0.32)kPa,24 h尿量为(615.0±185.5)ml和(1 240.0±255.0)ml;治疗前后相比,差异有高度显著性(P<0.01)。血清钾为(3.5±1.1)mmol/L和(4.0±1.3)mmol/L,腹水钾(3.6±0.9)mmol/L和(4.1±1.0)mmol/L;血清钠为(122.2±4.0)mmol/L和(126.5±4.3)mmol/L,腹水钠为(120.8±4.5)mmol/L和(123.3±4.7)mmol/L;血清氯为(90.3±6.2)mmol/L和(95.1±5.7)mmol/L,腹水氯为(92.0±5.9)mmol/L和(96.4±50.5)mmol/L;治疗前后相比,血清钠、腹水钠、腹水钾、血清氯、腹水氯差异均有显著性(P<0.05,P<0.01),血清钾差异无显著性(P>0.05)。冷冻浓缩腹水回输后,除2例出现一过性发热外,未发生低血压、肝昏迷、消化道出血现象,未出现蛋白凝集、堵塞管腔;未出现电解质紊乱现象。结论 冷冻浓缩腹水回输可大量回收腹水 相似文献
996.
紫杉醇诱导HL—60细胞凋亡的研究 总被引:2,自引:0,他引:2
目的:观察抗微管药紫杉醇对急性白血病细胞株HL-60是否具有凋亡诱导作用,并进一步研究bcl-2基因在此过程中的作用。方法:(1)以紫杉醇处理HL-60细胞,观察细胞生长抑制作用的时间效应和剂量效应,在光镜和电镜下观察细胞形态变化;(2)用流式细胞仪检测药物孵育前后细胞凋亡率(AP)的变化;(3)用RT-PCR法检测药物孵育前后bcl-2基因的表达水平。结果:(1)在一定剂量和时间范围内紫杉醇能抑制HL-60细胞生长;(2)紫杉醇能诱导HL-60细胞凋亡,并显示剂量效应:(3)在紫杉醇诱导HL-609细胞凋亡过程中,bcl-2基因表达水平下调。结论:紫杉醇能诱导HL-60细胞凋亡;bcl-2基因参与了紫杉醇诱导HL-60细胞凋亡的调控。 相似文献
997.
消炎痛对中晚期原发性肝癌病人NK细胞及T淋巴细胞亚群的影响 总被引:2,自引:0,他引:2
观察中晚期原发性肝癌病人在口服呋喃氟尿嘧啶的基础上加用消炎痛 (吲哚美辛 ) (治疗组 )和不加用消炎痛 (对照组 )外周血自然杀伤 (NK)细胞及T淋巴细胞亚群的变化。结果发现 :治疗组治疗后NK细胞活性较治疗前及较对照组治疗后显著提高 (P <0 .0 5 ,P <0 .0 1) ,而T淋巴细胞亚群的变化差异无显著性。提示消炎痛能增强中晚期原发性肝癌NK细胞的活性 相似文献
998.
BACKGROUND: Systemic sclerosis (SSc) is a generalized disorder of the interstitial tissues and vasculature with distinct abnormalities in three systems, immune and autoimmune, vascular and microvascular, and mesenchymal extracellular matrix (ECM), that lead to exuberant fibrosis. The aim of this study was to compare the number of blood vessel profiles in the marginal gingiva between SSc patients and patients with periodontitis but without SSc by using biopsies. METHODS: Marginal gingiva and gingival papilla were obtained from 13 scleroderma patients and 8 patients with periodontitis after routine tooth extraction and gingival curettage. On the histological sections, immunohistochemical investigations were performed using the avidin-biotin complex method (ABC) and the monoclonal antibody CD 31/Clone JC70A (platelet endothelial cell adhesion molecule-1). Blood vessels were identified by light microscopy (original magnification x400) and counted within 0.3615 mm2. Medians of blood vessel profiles were compared by Mann-Whitney U-test. RESULTS: There is no statistical difference between the median of blood vessel profiles in the marginal gingiva of SSc patients as compared to the median of blood vessel profiles in the marginal gingiva of patients with periodontitis (P = 0.665). We did not discover avascular areas in the subepithelial connective tissue. DISCUSSION: The pathological changes in the microvasculature in the dermis of SSc patients are not transferable to the marginal periodont, as intraindividual histological examinations of dermis and oral mucosa in relation to the degree of the disease are not available yet. 相似文献
999.
经皮腔内冠状动脉成形术对心脏自主神经活动的影响 总被引:3,自引:3,他引:0
目的:观察经皮腔内冠状动脉成形术(PTCA)后心率变异(HRV)的变化,探讨PTCA和HRV的影响。方法:PTCA患者120例,24h动态心电图(DCG)记录PTCA术前1周、术后1周、术后6个月的心电信息并进行HRV分析。结果:PTCA术后6个月HRV指标中的24RR间期标准差(SDNN(和高频段的功率谱密度(HFP)较术前明显增高(P分别不小于0.05及0.01);PTCA术后冠状动脉再狭窄患 相似文献
1000.
胸腺肽对肠梗阻细菌移位的影响 总被引:8,自引:2,他引:6
目的:通过对大鼠机械性肠梗阻模型细菌移位的实验研究,了解应用胸腺肽后,大鼠肠梗阻致细菌移位的改变情况,探索减少细菌移位的可能药物。方法:雄性SD大鼠30只,随机分为假手术组,肠梗阻组和胸腺肽组。检测肝脏和肠系膜淋巴细菌移位情况、血浆内毒素水平和进行回肠病理学检查等。结果:细胞移位率和细菌移位数水平,肠梗阻组和假手术组相比,明显升高,胸朱肽组和肠阻组相一少,血浆内毒素水平,胸腺肽组与肠梗阻组相比明显 相似文献