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71.
α-葡萄糖苷酶抑制剂治疗2型糖尿病的系统评价   总被引:4,自引:0,他引:4  
目的评价α-葡萄糖苷酶抑制剂治疗2型糖尿病患者的效果。方法检索Cochrane图书馆、MEDLINE、EMBASE、CurrentContents、LILACS在研试验数据库,主题为α-葡萄糖苷酶抑制剂的综述的参考文献,并联系纳入试验的专家与实施者。最近检索日期为2003年月12月(CurrentContents)和2003年4月(其他数据库)。纳入α-葡萄糖苷酶抑制剂单一疗法与其它干预比较,治疗2型糖尿病疗程至少12周的随机对照试验,并且试验至少包括以下结局之一:病死率、患病率、生活质量、血糖控制、血脂、胰岛素水平、体重、不良事件。两名评价者独立阅读所有摘要,评价质量并提取数据,分歧通过协商解决或由第三位评价者裁决。由一位统计学家在对提取数据输入数据库时进行检查。我们尽量联系所有作者以核实数据。结果共纳入41个试验、8130例受试者,其中30个针对阿卡波糖,7个针对米格列醇,1个针对优格列波糖,还有3个为不同α-葡萄糖苷酶抑制剂间的比较。绝大多数研究疗程为24周,仅有2个研究超过1年。与安慰剂相比,阿卡波糖血糖控制效果更好:糖化血红蛋白–0.8%[95%CI(–0.9,–0.7)],空腹血糖–1.1mmol/L[95%CI(–1.4,–0.9)],负荷血糖–2.3mmol/L[95%CI(–2.7,–1.9)],阿卡波糖对糖化血红蛋白的作用呈非剂量依赖。我们发现其可降低负荷胰岛素,但对血脂和体重未见临床相关的作用。不良反应主要来自胃肠道且与剂量相关。相对于磺脲,阿卡波糖将空腹和负荷胰岛素水平分别降低至–24.8pmol/L[95%CI(–43.3,–6.3)]和–133.2pmol/L[95%CI(–184.5,–81.8)],但阿卡波糖引起的不良反应更多。结论关于α-葡萄糖苷酶抑制剂是否影响2型糖尿病患者的病死率和患病率仍不清楚。相反,其对血糖控制或胰岛素水平作用明显,对血脂和体重的作用差异无统计学意义。α-葡萄糖苷酶抑制剂更长疗程的效果仍不确定。阿卡波糖剂量超过50mg(TID)时不能进一步影响糖化血红蛋白水平,不良反应反而更多,与磺脲相比,α-葡萄糖苷酶抑制剂降低了空腹和负荷胰岛素水平,但在血糖控制和不良反应方面存在不利影响。  相似文献   
72.
The elastic properties of chiral and non-chiral single-walled boron nitride nanotubes in a wide range of their chiral indices and diameters were studied. With this aim, a three-dimensional finite element model was used to assess their rigidities and, subsequently, elastic moduli and Poisson’s ratio. An extensive study was performed to understand the impact of the input parameters on the results obtained by numerical simulation. For comparison, the elastic properties of single-walled boron nitride nanotubes are shown together with those obtained for single-walled carbon nanotubes.  相似文献   
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Mononuclear cells from patients infected with Schistosoma mansoni were able to produce a soluble material that inhibited the granulocyte cytotoxicity against schistosomula in a complement-dependent killing assay. This granulocyte inhibitory factor (GIF) appears to exist preformed in the mononuclear cells of patients, but it can also be released in the supernatant after antigenic stimulation (lymphokine-like). Only T lymphocytes were able to mediate the inhibition of granulocyte cytotoxicity against schistosomula in vitro. The treatment of S. mansoni-infected mice with GIF induced a significant decrease in the liver granuloma size.  相似文献   
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Samples of two carnivore fish species (Hoplias malabaricus and Serrasalmus brandtii) were collected along Contas River, northeastern Brazil, to determine the levels of Co, Cr, Cu, Fe, Mn, Ni and Pb in edible and non-edible tissues of these important local fisheries resources. Lead could not be quantified in most of the samples, while the other metals were detected in both species. In edible parts, Cr levels were above Brazilian threshold limits in all specimens and Ni was at high concentration in S. brandtii individuals from one collection site. In non-edible parts (viscera), besides Cr, Cu concentration was higher than that recommended by Brazilian laws. Both fish species proved to be sensitive to environmental contamination. Despite the different ecological characteristics, such as vagility and feeding strategy, these fish showed that aquatic predators are efficient bioindicators of water quality and biomagnification.  相似文献   
79.
Endocannabinoids (ECBs) are ubiquitous lipophilic agents, and this characteristic is consistent with the wide range of homeostatic functions attributed to the ECB system. There is an increasing number of studies showing that the ECB system affects neurotransmission within the hypothalamic neurohypophyseal system. We provide an overview of the primary roles of ECBs in the modulation of neuroendocrine function and, specifically, in the control of hydromineral homeostasis. Accordingly, the general aspects of ECB‐mediated signalling, as well as the specific contributions of the central component of the ECB system to the integration of behavioural and endocrine responses that control body fluid homeostasis, are discussed.  相似文献   
80.

Purpose

It has been suggested that subjective measures of oral health are influenced by both individual and contextual characteristics. This study assessed the relationship between neighborhood and individual social networks and child oral health-related quality of life (COHRQoL).

Methods

This study followed a cross-sectional design using a multistage sample of 478 children aged 1–5 years old. Caregivers completed the Brazilian version of the Early Childhood Oral Health Impact Scale (ECOHIS) and answered questions related to socioeconomic status and social network. The dental examination provided information on the prevalence of dental caries, dental trauma, and occlusion. Contextual social determinants included the presence of cultural community centers and of workers’ association in the neighborhood. Data analysis considered the total ECOHIS scores as the outcome and neighborhood/individual social networks as the independent variables. A multilevel Poisson regression model was used to investigate the association among individual and contextual characteristics and COHRQoL.

Results

Total ECOHIS scores ranged from 0 to 41 (possible range 0–52). The mean ECOHIS score was low (mean = 1.8, SD = 3.9), and the functional domain presented the highest mean impact on COHRQoL (mean = 0.5, SD = 1.4). Following adjusted analysis, low household income, visiting a neighbor less than once a month, the presence of anterior open bite, dental trauma, and dental caries were identified as individual determinants of negative impact on a child’s quality of life. These variables remained associated with the outcome even after adding the contextual-level variables in the model. At the contextual level, the presence of community cultural centers was associated with overall mean ECOHIS score; higher impacts on COHRQoL were observed in those living in neighborhoods without cultural community centers.

Conclusion

There is a significant association between individual and contextual social determinants and COHRQoL; unfavorable social conditions and poor socioeconomic status have a negative impact on caregiver reports of children’s oral health-related quality of life.  相似文献   
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