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71.
猪精液抑制素的制备及其放射免疫分析   总被引:5,自引:0,他引:5  
本文报道以猪精液为原料制备的抑制素的生物活性、氨基酸组成、分子量以及抑制素的放射免疫分析。新鲜猪精液经乙醇沉淀、丙酮清洗和Sephadex G-100凝胶过滤,获得抑制素活性组分UⅡ。生物测定表明:所得抑制素单位重量的生物活性稍高于Chari氏牛精液抑制素纯品的活性;UⅡ含17种氨基酸,分子量为18,500道尔顿,用UⅡ免疫家兔,获得亲和为强(Ka=6.58×10~(10)L/M)、效价高的特异抗血清,终稀释度可达1:100,000;用双抗体法进行猪精液抑制素放射免疫分析,检测灵敏度为87.5微微克,经Logit转换,标准曲线的直线化较好。按Cerceo效点法综合评价,积分值达28,表明此法较优。  相似文献   
72.
Summary Twenty evaluable patients with advanced measurable colorectal cancer received 3-week courses of a combination of IV dacarbazine 300 mg/m2/day from day 1 to day 5 and IV mitomycin 2 mg/m2/day from day 1 to day 5. Fourteen of these patients had had no prior chemotherapy and received two or more courses of this two-drug regimen. None of the patients achieved complete or partial response. Severe to life-threatening myelosuppression, was encountered in patients with prior radiotherapy and or prior chemotherapy, and/or in patients with a Karnofsky score 70. Hematologic toxicity was mild in the other patients. Nonhematologic toxic effects were generally mild to moderate and consisted essentially in nausea and vomiting. It is concluded that in our hands the regimen selected for this trial has no significant antitumor activity in advanced colorectal cancer.  相似文献   
73.
目的 :探讨干预CD86协同刺激信号在诱导母胎界面局部形成Th2型免疫偏倚中的作用。方法 :将正常妊娠模型 (CBA×BALB/c)和自然流产模型 (CBA×DBA/ 2 )CBA孕鼠均分为两组 ,于孕第 4、6、8天 ,对照组腹腔注射大鼠IgG ,实验组腹腔注射大鼠抗小鼠CD86mAb ;孕第 9天 ,ELISA测定母胎界面组织培养上清中Th1型 (IFN γ、TNF α) /Th2型(IL 4、IL 10 )细胞因子表达水平 ,并计算IL 4 /IFN γ、IL 10 /IFN γ比值 ;孕第 12天比较两种模型各组的胚胎吸收率。结果 :正常妊娠模型中 ,干预CD86协同刺激信号对母胎界面原有的Th2型免疫偏离及妊娠预后均无显著影响。自然流产模型中 ,干预CD86协同刺激信号能够诱导母胎界面局部形成Th2型免疫偏倚并显著改善其妊娠预后。结论 :于孕早期 ,干预CD86协同刺激信号能够改善母胎界面局部细胞因子微环境 ,形成维持正常妊娠所需的Th2型免疫偏倚 ,诱导母胎免疫耐受  相似文献   
74.
目的:探索上海地区农民人群中α-雌激素受体基因(ER-α)及芳香烃受体基因(Ahr)不同基因形态和老年痴呆症高发风险的可能联系.方法:分别以PCR—RFLP和AS—PCR方法分析一组老年痴呆症患者(n=52)ER-α基因及Ahr基因的多态位点,同一地区的健康人群(n=125)为对照.结果:Alzheimer症病人ER-α基因两个位点突变形态频率显著高于对照人群(Pvu Ⅱ位点:P=0.023,OR=2.94,95%CI 1.13—7.71;Xba I位点:P=0.046,0R=2.28,95% CI 1.003—5.17).Ahr G1721A位点基因型频率在病人组和对照组间无显著差异.结论:ER-α基因多态性可能与Alzheimer症易感性个体差异有关,本工作不支持Ahr基因多态性与老年痴呆症高发风险间的可能关联.  相似文献   
75.
AIM: To study the effect of puerarin (Pue) on Na~+ channel in rat ventricular myocytes. METHODS: Whole-cell patch-clamp technique was applied on isolated cardiomyocytes from rats. RESULTS: Pue inhibited cardiac I_(Na) in a positive rate-dependent and dose-dependent manner, with an IC_(50) of 349 μmol/L. The kinetics of blockage of cardiac sodium channel by Pue resembled the ClassIa/Ic of antiarrhythmic agents. Pue 300 μmol/L did not alter the shape of the I-V curve of I_(Na), but markedly shifted the steady-state inactivation curve of I_(Na) towards more negative potential by 15.9 mV, and postponed the recovery of I_(Na) inactivation state from (21.9±1.6) ms to (54.4±3.4) ms (P<0.01 ). It demonstrated that the steady state of inactivation was affected by Pue significantly. CONCLUSION: Pue protected ventricular myocytes against cardiac damage and arrhythmias by inhibiting recovery from inactivation of cardiac Na~+ channels.  相似文献   
76.
1 BACKGROUNDTheincidenceofCPis 0 .7per 1 0 0 0livebirths[1 ] .Becausecerebralpalsyinfluencesthewaychildrendevelop,itoftenresultsindevelop mentaldisability .Today ,more peoplehavecerebralpalsythananyotherdevelopmentaldis ability ,includingDownsyndrome,epilepsy ,andautism .Accordingtoasurveyconductedin1 986,2 .6%ofthepopulationofPakistaniaredisabled (includingbothphysicalandmentaldis abilities) .Childrenbetween 0~1 4 yearsinageconstitute 40 %ofthedisabled populationinPakistan .Routineme…  相似文献   
77.
78.
We undertook criterion-based audit of the current practice of prescribing hormone replacement therapy for women with acute myocardial infarction; the audit included 181 consecutive women admitted to one hospital with this diagnosis in one calendar year. The set standard was that, barring any contraindication, all postmenopausal women with acute myocardial infarction should be prescribed hormone replacement therapy before discharge from hospital. The evidence base of this standard derives from more than 30 epidemiological and clinical studies and a large body of biological data. Only 4.7% of the women were current users of hormone replacement therapy and the set standard was met in only 3% of eligible nonusers. Professionals caring for women who have had a myocardial infarction need to consider hormone replacement therapy as a secondary prophylaxis of myocardial infarction. Gynaecologists should liaise with colleagues in other specialties and general practice to ensure that information on the nongynaecological benefits of hormone replacement therapy is widely disseminated.  相似文献   
79.
Objective To assess serum lipid and lipoprotein concentrations and oral glucose tolerance in postmenopausal women treated with 17β-oestradiol (2 mg/day) and cyclical dydrogesterone (10 mg/day for 14 days per 28 day cycle).
Design A 24 month prospective study of 29 women acting as their own controls. On-treatment samples were taken during the combined (oestrogen–progestogen) phase of therapy.
Setting Metabolic research unit in London.
Population Postmenopausal women with no previous exposure to hormone replacement therapy attending a menopause clinic in a London hospital.
Methods Fasting serum sampling and oral glucose tolerance testing.
Main outcome measures Serum lipids and lipoprotein concentrations and plasma glucose, insulin and C-peptide responses to an oral glucose load.
Results Restricting the analysis to the 17 women who completed the study, no effect was seen on serum triglyceride concentrations. There was a mean fall of 5.9% (95% CI 1.2 to −13.0) in concentrations of serum total cholesterol, reflecting the balance of a 10.7% fall (95% CI 4.3 to −25.8) in low density lipoprotein cholesterol concentrations and a 16.3% increase (95% CI 7.3 to −25.3) in those of high density lipoproteins. Fasting glucose concentrations and glucose tolerance test responses were unchanged. Fasting insulin concentrations fell substantially (–41.6%, 95% CI −23.4 to −59.8) with falls also being seen in insulin responses to glucose. Fasting C-peptide concentrations increased by 36.2% (95% CI 9.17 to 63.3), with no consistent effect on C-peptide responses to glucose.
Conclusions Dydrogesterone did not appear to oppose the potentially beneficial effects of oestradiol on insulin or either low or high density lipoproteins, making the combination with 17β-oestradiol a potentially useful option for postmenopausal women particularly those at risk of cardiovascular disease or diabetes mellitus.  相似文献   
80.
Objective To investigate the correlation between soluble forms of the intercellular adhesion molecule (SICAM-1) and vascular cell adhesion molecule (sVCAM-1) and the severity of pre-eclampsia or its possible consequences for fetal growth.
Design Prospective observational study.
Setting Institute of Medical Genetics, University of Oslo, Department of Medical Genetics and Haematological Research Laboratory, Ullevål University Hospital; and the Department of Obstetrics and Gynaecology, The National Hospital, Oslo, Norway.
Participants Seventy-six women with normotensive pregnancies and 157 women with pre-eclampsia divided into three subgroups: mild, severe and pre-eclampsia with fetal growth retardation.
Methods ELISA-measurements of plasma SICAM-1 and sVCAM-1 were performed in a group of healthy pregnant normotensive women and three groups of women with varying degrees of pre-eclampsia.
Results SICAM-1 concentrations were higher in the pre-eclampsia group compared with the control group, but this difference was not statistically significant. Plasma concentrations of sVCAM-1 were significantly greater ( P < 0.0001) in all pre-eclampsia subgroups (835.34, 855.25 and 964.05 ng/mL) compared with the control group (667.62 ng/mL). Within the pre-eclampsia group, plasma concentration of sVCAM-1 was significantly higher in the subgroup exhibiting fetal growth retardation ( P = 0.03) compared with mild pre-eclampsia.
Conclusion The observed increases in plasma concentrations of sVCAM-1 suggest that measurements of this adhesion molecule may be useful in monitoring pregnancies with respect to the development of pre-eclampsia or fetal growth retardation.  相似文献   
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