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71.
精子质量参数分析的标准化与质量控制的研究进展 总被引:4,自引:4,他引:0
精液分析是评价男性生育能力的最基本测试。最近几年,对精液分析标准化的迫切需求已引起男科学家的广泛重视。本文对精子质量参数———精子密度、活动率和形态学分析的标准化及质量控制进行了综述。精子密度分析的关键是计数池的标准化,因此Cell-VU计数池应该是最佳的选择;精子活动率和精子形态学的分析由于主观性太强,CASA系统可能是其标准化的最终选择。精液质量参数分析的质量控制主要是质量控制材料的选择,以及在男科学实验室实施EQC和IQC项目,而一些监测质量控制的图表和计算方法应被相应地建立。 相似文献
72.
73.
MARYANN NOCERA T. MING CHU 《American journal of reproductive immunology (New York, N.Y. : 1989)》1995,33(4):282-291
PROBLEM : Human seminal plasma is known to exhibit immunosuppressive activity. Transforming growth factor β (TGF-β) has been identified as an immunosuppressive factor in human seminal plasma. Biologically active TGF-β represents a family of 25-kDa homodimeric proteins linked with disulfide bonds. TGF-β associates with high molecular weight proteins noncovalently to form a type of latency that is biologically inactive. Quantitative distribution of active form of TGF-β versus inactive latent form of TGF-β, and mechanism of the TGF-β activation in human seminal plasma remain to be elucidated. PURPOSE : To characterize seminal plasma latent form of TGF-β, including its concentration, and the mechanism underlying the activation of TGF-β. METHOD : Gel filtrations on ACA-34 and Biogel P-60 were used to fractionate seminal plasma. TGF-β was measured by enzyme immunoassay using antibodies specific for TGF-β1 and TGF-β2, respectively. Radioreceptor assay with recombinant human [125I]-TGF-β1 was applied to qualitatively identify TGF-β1. Kinetic experiments with various pH, temperature and time, along with protease inhibitors, were performed to delineate the activation mechanism of latent TGF-β. RESULTS : Human seminal plasma contained both TGF-β1 and TGF-β2, predominantly in latent form. The total concentration of TGF-β1 averaged 238 ng/ml versus an average of 18 ng/ml for TGF-β2. The in vitro activation or release of TGF-β1, from latent TGF-β1 was achieved only at acidic pH of <4.0, and was time and temperature dependent. At pH 3.7 and 37°C, a significant activation of latent TGF-β1 was achieved after an incubation of only 15 min, reached the maximum at 120 min, and the activated TGF-β1 remained relatively stable for at least 24 h. The activation was not inhibitable by a series of protease inhibitors examined, alone or in combination (e.g., phenylmethylsulfonyl fluoride, E-64, pepstatin, leupeptin, ethylenediamine tetraacetic acid). Competitive radioreceptor assay established the functional identity of TGF-β1 in human seminal plasma with recombinant human TGF-β1. CONCLUSION : Human seminal plasma TGF-β is biologically activated from high molecular weight latent TGF-β by acid pH. The acidic environment of female lower genital tract could represent an in vivo physiological condition for activation of seminal plasma TGF-β that may immunologically protect the integrity of sperm. 相似文献
74.
Lower level of serum potassium and higher level of C-reactive protein as an independent risk factor for giant aneurysms in Kawasaki disease 总被引:7,自引:0,他引:7
Giant aneurysms are the most serious issue of patients with Kawasaki disease (KD). To clarify risk factors for these giant aneurysms, we conducted a matched case-control study. Among the patients reported in nationwide surveys, 117 patients with giant aneurysms had an unequivocal new diagnosis and presented at the treatment center within 9 d of illness. We obtained clinical information on admission of about 69 patients (case) from the treatment centers. One control was selected for each case, an age- and sex-matched patient without coronary involvement, reported from the same treatment center at about the same time as the case, and we obtained the same clinical information about controls. Fourteen variables were analysed with a conditional logistic regression model: body temperature, hematocrit, hemoglobin, numbers of leukocyte and platelets, concentrations of serum albumin, globulin, total cholesterol, sodium, potassium and chloride, erythrocyte sedimentation rate, C-reactive protein and alanine aminotransferase activity. After adjustment for age, duration of illness before admission and use of intravenous gamma globulin therapy, C-reactive protein [odds ratio (OR) = 1.142, 95% confidence interval (CI) 1.054-1.237], alanine aminotransferase activity (OR = 1.008, 95% CI 1.002-1.014), serum sodium concentration (OR = 0.877, 95% CI 0.770-0.999) and serum potassium concentration (OR = 0.319, 95% CI 0.124-0.822) were significantly related to the risk for giant aneurysms. Further analyses with these four explanatory variables revealed that C-reactive protein (OR = 1.159, 95% CI 1.022-1.315) and serum potassium concentration (OR = 0.222, 95% CI 0.052-0.948) met the significant level. Thus, the values for serum C-reactive protein and potassium are independent risk factors for the development of the giant aneurysms of Kawasaki disease. 相似文献
75.
阿霉素不同剂量静脉注射的药动学及其临床意义 总被引:1,自引:0,他引:1
采用HPLC法测定14例肿瘤患者使用不同剂量阿霉素的血药浓度,并计算药代参数。40mg/m2和25mg/m2两组的血药峰浓度、AUC、Vc差异有显著性。阿霉素的药代动力学存在明显的个体差异,血药峰浓度、Vc、K12与疗效相关。 相似文献
76.
French Donna L. Häglund Bert O. Himmelstein Kenneth J. Mauger John W. 《Pharmaceutical research》1995,12(10):1513-1520
Purpose. The objective of this study is to correlate drug release mechanism with measured drug concentration profiles in gel layers of Carbopol® matrices containing mesalamine or benzoic acid.
Methods. Release rate experiments with Carbopol® matrices were performed using a rotating disk apparatus. Matrices were frozen and the gel layer in the matrices was sliced using a microtome in a cryostat. Drug concentration profiles were determined by direct measurement of the concentration of the drug in the gel slices. The pH of the slices was measured using microelectrodes, and water content was measured by Karl Fisher titration.
Results. The concentration gradient in mesalamine matrices decreased over time and correlated with square root of time release rate kinetics. The concentration profiles of benzoic acid were unchanged over time and correlated with zero order release rate kinetics. Carbopol gel layers were highly hydrated (93–95% water). Gel layers in matrices with mesalamine had a more alkaline microenvironmental pH. This higher pH resulted in increased growth of the thickness of the gel layer and a reduction drug diffusivity in comparison to benzoic acid matrices.
Conclusions. The release rate kinetics of mesalamine and benzoic acid correlated to the measured concentration profiles. The shape of the concentration profiles is determined by the rate of growth of the Carbopol® gel layer and drug diffusivity. 相似文献
77.
微量尿和血清样品中氟的测定方法研究 总被引:16,自引:1,他引:15
本研究利用改进的氟测定方法,测定尿和血清样品中氟离子的含量。结果表明,该方法样品用且少,线性响应范围、精密度、回收率和重现性等指标均符合方法学的要求,与常规法比较,显示测定结果间无显著性差异。可广泛使用于要求高、样品量少的生物材料氟检测。 相似文献
78.
Objective: To evaluate the effectiveness of Coca-Cola in enhancing the absorption of itraconazole.
Methods: Eight healthy volunteers were randomized to receive two treatment sequences in a two-way crossover design with a 1-week
wash-out period separating each study treatment. Treatment I, the control, consisted of 100 mg itraconazole with 325 ml water.
Treatment II was identical to treatment I, except that itraconazole was administered with 325 ml of Coca-Cola (pH 2.5).
Results: Serum itraconazole concentrations, after administration with Coca-Cola (treatment II), were higher than after administration
with water (treatment I). The mean AUC was 1.12 vs 2.02 μg · h · ml−1, the mean Cmax was 0.14 vs 0.31 μg · ml −1and the mean tmax was 2.56 vs 3.38 h in treatments I and II, respectively.
Conclusion: The absorption of itraconazole can be enhanced by Coca-Cola.
Received: 4 November 1996 / Accepted in revised form: 21 January 1997 相似文献
79.
本文将Rowland等人的二房室模型中的消除过程扩展成米氏兼一级消除过程。据此,推导出达到稳态浓度的时间、血药浓度-时间曲线下面积和生物利用度的公式;进而得到平均清除率和剂量间的关系以及剂量与平均清除率和血浆浓度呈线性关系的结论。 相似文献
80.