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91.
92.

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   
93.
In a sample of 761 heroin injectors in Baltimore, Maryland, correlates of arrest for drug-related and non-drug-related criminal offenses, by gender, were examined. This investigation examined gender differences in involvement in the drug economy and correlates of arrest. Correlates included roles in the street drug economy, social network attributes, and economic and demographic variables. Gender differences were found. Selling drugs was strongly associated with drug-related arrests for males. Steering (i.e., publicizing drug brands) was highly associated with drug-related arrests for females. Level of heroin addiction was associated with drug-related arrests for males, but not for females. The associations of social network variables with arrests also differed by gender. For females but not males, a higher number of females in one’s network was associated with a lower frequency of arrests. For males, having at least one heroin injector in the personal network was associated with a decreased frequency of arrest, while for females the direction of the association was reversed. These findings suggest the importance of modeling drug behaviors by gender.  相似文献   
94.
Ventral hernia repair: a study of current practice   总被引:5,自引:5,他引:0  
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias. Clinical trials are required to establish the best method of repair for this common condition. Electronic Publication  相似文献   
95.
Types of drugs used and routes of administration were assessed, and correlations to social affiliation, HIV status, and lifestyle stability were explored among 672 street-recruited drug users in Baltimore. Participants reported 63 patterns of drug use, which were categorized into five groups: (1) only sniff heroin; (2) smoke crack and may snort cocaine; (3) sniff heroin and smoke crack; (4) inject heroin and cocaine; and (5) inject heroin and cocaine, smoke crack, and may snort heroin. Social network analysis revealed that heroin sniffers and crack smokers both tended to associate with those with similar drug use patterns. High symptoms of drug dependence were observed among heroin users irrespective of mode of administration. Injectors reported higher rates of hospitalization compared to noninjectors even after adjusting for HIV status. Implications to HIV prevention and drug use transitions are discussed.  相似文献   
96.
This study compared the safety and efficacy of sublingual buprenorphine tablets with oral methadone in a population of opioid-dependent individuals in a double-blind, randomized, 6-week trial using a flexible dosing procedure. Fifty-eight patients seeking treatment for opioid dependence were recruited in three outpatient facilities and randomly assigned to substitution with buprenorphine or methadone. The retention rate was significantly better in the methadone maintained group (90 vs. 56%; P<0.001). Subjects completing the study in both the treatment groups had similar proportions of opioid positive urine samples (buprenorphine 62%; methadone 59%) and positive urine specimens, as well as mean heroin craving scores decreased significantly over time (P=0.035 and P<0.001). The proportion of cocaine-positive toxicology results did not differ between groups. At week six mean stabilization doses were 10.5 mg per day for the sublingual buprenorphine tablet, and 69.8 mg per day for methadone, respectively. Patient performance during maintenance was similar in both the groups. The high attrition rate in the buprenorphine group during the induction phase might reflect inadequate induction doses. Thus, buprenorphine is a viable alternative for methadone in short-term maintenance treatment for heroin dependence if treatment induction is done with adequate dosages.  相似文献   
97.
目的构建人端粒酶逆转录酶(hTERT)片段的真核表达质粒。方法用RT-PCR方法从肝癌组织中提取总RNA扩增出hTERT基因片段,将其连接pGEM-TEasy质粒上,将重组质粒pGEM-T-hTERT和pEGFP-C3真核绿色荧光蛋白表达载体同时用HindⅢ和BamHⅠ双酶切后进行连接,再将重组的pEGFP-C3-hTERT基因片段转染NIH3T3细胞,经G418筛选获得稳定转染的细胞系,荧光倒置显微镜观察并检测转染细胞的hTERTmRNA表达水平。结果DNA序列分析证实了重组载体pGEM-T-hTERT和pEGFP-C3-hTERT内插入片段的碱基组成与公开发表的hTERT序列一致。转染pEGFP-C3-hTERT的NIH3T3细胞可见绿色荧光,并检出高水平表达的hTERT。结论成功构建高效表达hTERT的真核表达载体,为以hTERT为靶点的肿瘤治疗打下实验基础。  相似文献   
98.
目的:该实验旨在研究急性肺损伤(ALI)时肺泡Ⅱ型上皮细胞(AEC-Ⅱ)超微结构变化和肺组织表面活性蛋白SP-A含量的变化关系,从而探讨ALI的发病机制。方法:48只Sprague-Dawley幼鼠被随机分为正常对照组和ALI组。 腹腔注射脂多糖(LPS,4 mg/kg)建立ALI模型,正常对照组注射等量生理盐水。 LPS注射后24,48,72 h每亚组各处死8只大鼠。 取左肺下肺组织待透射电镜检查。 用Western blot方法测定肺组织SP-A的相对含量。结果:ALI 24 h时,AEC-Ⅱ微绒毛消失。24 h及48 h时板层小体(lamellar body, Lb)数量增加,体积增大,密度减低,排空明显增强,呈指环状绕核排列,细胞增生活跃,代谢旺盛。48 h时Lb呈巨大空泡样变性。肺组织SP-A含量明显高于对照组(24 h时ALI组为6.52±0.62,对照组为5.02±0.35, P< 0.01;48 h时ALI组为6.65±0.62,对照组为5.01±0.36,P< 0.01)。72 h时Lb破溃,数目明显减少,细胞核形态不规则,部分核边界不清,肺组织SP-A含量下降(ALI组为3.87±0.50,对照组为5.22±0.36,P<0.01)。结论: LPS致幼鼠ALI时AEC-Ⅱ和肺组织SP-A的变化为时间依赖性,随AEC-Ⅱ损伤程度的加重肺组织SP-A由代偿转为失代偿,可能是发生ARDS的重要机制之一。  相似文献   
99.
通过探讨细化药品采购环节:包括建立和完善采购制度,优选药品配送企业,制定合理的采购时间、合理采购价格和合理的库存结构及库存水平。以便及时、准确地为临床用药提供安全、有效、经济的药品以及全方位保障药品供应。  相似文献   
100.
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