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排序方式: 共有760条查询结果,搜索用时 15 毫秒
1.
目的:采用HPLC法测定四川粉葛中葛根素的含量。方法:色谱柱为依利特C18柱(4.6min&;#215;150mm,5μm),流动相为甲醇-水(25:75),流速为0.8ml/min,检测波长为250nm,柱温为25℃。结果:葛根素在0.0880~0.7040μg范围内峰面积与进样量呈良好的线性关系,回归方程为A=336.35X-1.7716,r=1.0000,其平均同收率为100.01%,RSD为0.14%(n=6)。结论:该方法简便易行,结果准确,可用于四川粉葛药材的质量控制。 相似文献
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A new dimension to the Barker hypothesis: low birthweight and susceptibility to renal disease. 总被引:16,自引:0,他引:16
BACKGROUND: There is an epidemic of renal failure among Aborigines in the Australia's Northern Territory. The incidence is more than 1000 per million, and is doubling every three to four years. We evaluated the relationship of birthweight to renal disease in adults in one high-risk community. METHODS: We screened more than 80% of people in the community for renal disease, using the urine albumin/creatinine ratio (ACR, g/mol) as the marker, and reviewed records for birthweights. RESULTS: Birthweights were available with increasing frequency for people born after 1956. In 317 adults aged 20 to 38 years at screening, the mean birthweight (SD) was 2.712+/-0.4 kg, and 35% had been low birthweight (LBW, less than 2.5 kg). Birthweight was positively correlated with body mass index (BMI), blood pressure, and diabetes rates, but was inversely correlated with ACR. The odds ratio for overt albuminuria in LBW persons compared with those of higher birthweights was 2.82 (CI, 1.26 to 6.31) after adjusting for other factors, and LBW contributed to an estimated 27% (CI, 3 to 45%) of the population-based prevalence of overt albuminuria. Multivariate models suggest that increasing BMI and blood pressure and decreasing birthweight act in concert to amplify the increases in ACR that accompany increasing age. CONCLUSIONS: LBW contributes to renal disease in this high-risk population. The association might be mediated through impaired nephrogenesis caused by intrauterine malnutrition. The renal disease epidemic in Aborigines may partly be the legacy of greatly improved survival of LBW babies over the last four decades. Disease rates should eventually plateau as birthweights continue to improve, if postnatal risk factors can also be contained. 相似文献
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We defined erythropoietin (EPO) resistance by the ratio of the weekly EPO dose to hematocrit (Hct), yielding a continuously distributed variable (EPO/Hct). EPO resistance is usually attributed to iron or vitamin deficiency, hyperparathyroidism, aluminum toxicity, or inflammation. Activation of the acute-phase response, assessed by the level of the acute-phase C-reactive protein (CRP), correlates strongly with hypoalbuminemia and mortality in both hemodialysis (HD) and peritoneal dialysis (PD) patients. In this cross-sectional study of 92 HD and 36 PD patients, we examined the contribution of parathyroid hormone (PTH) levels, iron indices, aluminum levels, nutritional parameters (normalized protein catabolic rate [PCRn]), dialysis adequacy (Kt/V), and CRP to EPO/Hct. Albumin level serves as a measure of both nutrition and inflammation and was used as another independent variable. Serum albumin level (deltaR2 = 0.129; P < 0.001) and age (deltaR2 = 0.040; P = 0.040) were the best predictors of EPO/Hct in HD patients, and serum albumin (deltaR2 = 0.205; P = 0.002) and ferritin levels (deltaR2 = 0.132; P = 0.015) in PD patients. When albumin was excluded from the analysis, the best predictors of EPO/Hct were CRP (deltaR2 = 0.105; P = 0.003) and ferritin levels (deltaR2 = 0.051; P = 0.023) in HD patients and CRP level (deltaR2 = 0.141; P = 0.024) in PD patients. When both albumin and CRP were excluded from analysis in HD patients, low transferrin levels predicted high EPO/Hct (deltaR2 = 0.070; P = 0.011). EPO/Hct was independent of PTH and aluminum levels, PCRn, and Kt/V. High EPO/Hct occurred in the context of high ferritin and low transferrin levels, the pattern expected in the acute-phase response, not in iron deficiency. In well-dialyzed patients who were iron replete, the acute-phase response was the most important predictor of EPO resistance. 相似文献
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目的:性治疗法目前尚未普及,本研究旨在评价性治疗法联合西地那非治疗勃起功能障碍(ED)的疗效。方法:根据治疗方法的不同将在本院治疗随访过的3130例维吾尔族ED患者分成2组。对照组625例,单纯口服西地那非3个月;试验组2505例,采用性治疗法联合西地那非治疗3个月。采用国际勃起功能问卷表(IIEF-5)在各组治疗前、后进行疗效评估,并随访12个月。结果:对照组治疗前、后及在6个月、12个月随访的IIEF-5评分分别为12.80±3.76、18.10±2.61、17.35±2.73和16.64±2.63;试验组治疗前、后及在6个月、12个月随访的IIEF-5评分分别为12.73±3.52、19.06±4.07、19.86±2.42和20.47±2.38。两组治疗前后IIEF-5评分自身对比差异均有显著性(P<0.05)。组间比较,试验组较对照组6个月和12个月随访IIEF-5评分均有显著性差异(P<0.05)。结论:性治疗法联合西地那非治疗ED的效果优于单纯西地那非治疗,并在12个月的随访中稳定性良好。 相似文献
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寰椎椎弓根螺钉置钉技巧探讨 总被引:2,自引:0,他引:2
[目的]探讨寰椎椎弓根螺钉固定治疗寰枢椎不稳的置钉技巧。[方法]总结2000年10月~2008年9月应用寰椎椎弓根螺钉技术治疗寰枢椎不稳患者66例,置钉132枚。术中在直视下依据手感行寰椎椎弓根螺钉置钉,复位固定。[结果]本组66例132枚螺钉均成功置入,复位固定满意。术中未发现脊髓、神经根、椎动脉等损伤。术后患者症状及神经脊髓功能均有不同程度恢复。96枚螺钉术后行CT检查,其中91枚位置良好(94.89%)。全部病例内固定无松动、断裂,植骨均融合。[结论]术前影像学测量,术中显露寰椎后弓、直视下依据手感置钉、X线确定进钉方向,是安全置钉的技巧。 相似文献
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目的 探索豚鼠耳蜗基底膜振动测试的方法。方法 用戊巴比妥钠腹腔注射麻醉豚鼠后,腹侧切口,逐层切开皮肤,分离肌肉,可见听泡位于豚鼠下颌骨内侧深面,钝性分离听泡表面的肌肉组织,暴露听泡,用电钻将听泡打开,可见螺旋形耳蜗结构,辨认基底膜所在的部位。用电钻在需要开孔的骨壁上轻磨一个环形的凹陷,待足够薄弱的时候用尖头的刀片挑开骨片。用具有微细尖端的不锈钢针蘸取少量反光微珠,放置在基底膜上。然后用激光多普勒测振仪(laser doppler vibrometer,LDV)测量基底膜在外耳道纯音激励下的振动。结果 用该方法测量了豚鼠耳蜗基底膜在不同频率声波激励下的响应曲线。结论 该方法可进行豚鼠耳蜗基底膜振动的离体实验,但活体的振动测试尚需进一步的探索。 相似文献