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11.
Human T lymphocyte subsets, identified by means of OKT3, 4 and 8 monoclonal antibodies, were isolated by a fluorescence activated cell sorter (FACS IV) and analyzed for distribution of alpha-naphthyl acetate esterase (ANAE) activity. As compared to OKT8+ lymphocytes a higher proportion of OKT4+ lymphocytes was ANAE-positive exibiting a spot or dot-like pattern in the cytoplasm. OKT8 and 4 positive subsets showed a similar ANAE distribution in diffuse granular form. Although OKT4 and OKT8 populations presented a different ANAE dot-like reactivity, this marker did not allow as clear a distinction between them as that reported for TG and TM lymphocytes.  相似文献   
12.
低铅染毒大鼠体内脂质过氧化及抗氧化水平改变   总被引:1,自引:0,他引:1  
目的:观察低剂量铅染毒后大鼠体内脂质过氧化水平改变,为铅的毒作用机制研究提供依据。方法:以醋酸铅为受试物,雄性Wistar大鼠为受试对象,分别观察其脏器脂质过氧化水平改变。结果:低铅染毒后,大鼠各脏器超氧化物歧化酶(SOD)、谷胱苷肽过氧化物酶(GSH-Px)及过氧化脂质(LPO)均有不同程度改变(P<0.05,P<0.01),而巯基(-SH)含量仅肝脏变化较明显。结论:较低剂量的铅即可引起体内脂质过氧化水平的改变,而这种变化可能是铅的毒作用途径之一。  相似文献   
13.
Summary One-hundred and seventy patients with estrogen receptor positive (10 pmol/g protein) advanced breast cancer have been treated in a prospective randomized study either with continuous tamoxifen 30 mg × 1 daily (TAM), or with TAM 30 mg × 1 daily for 8 weeks alternating with medroxyprogesterone acetate 500 mg × 2 daily for 8 weeks (TAM/HD-MPA). The response rate was 62% in the group treated with cyclic TAM/HD-MPA versus 41% in the TAM alone group (p = 0.02). There was no significant difference in duration of remissions or survival.  相似文献   
14.
A new material, an emulsion of poly(vinyl acetate) was experimentally developed and clinically used to overcome several disadvantages in currently used liquid embolisation materials. The emulsion microparticles, 0.3–0.7 m in size, possessed cationic charge on the surface and hence aggregated immediately on contact with fluids containing anions. This inert polymer has the advantage that it does not induce a deleterious reaction in living tissue. Moreover, its medium is water and it is not adhesive, like the cyanoacrylates. Several concentrations of emulsion were injected into the renal arteries of dogs. For the investigation of tissue reactions and the possibility of recanalisation, the emulsion was injected into rats both subcutaneously and into the renal arteries. The renal artery injections in dogs showed adequate radiopacity and consistent complete occlusion. The lower the concentration of the emulsion, the smaller the arteries which could be occluded. Even at very low concentrations, however, venous occlusion did not occur. Histological study of the embolised rat kidney revealed no detectable damage in the vessel wall and no recanalisation for up to 6 months. The subcutaneously injected PVAc emulsion elicited mononuclear cell infiltration and gradual centripetal fibrosis, without any deleterious effect on the surrounding tissue. A cerebral arteriovenous malformation (AVM) was embolised using the material. Histology of the resected nidus showed findings similar to those in the animal experiments.  相似文献   
15.
Purpose Nafarelin acetate is a new gonadotropin releasing (GnRH) agonist analogue with unique potency, intranasal administration, and convenient storage. Hence, nafarelin was considered as an alternative for temporary pituitary suppression in patients undergoing ovulation induction in IVF. A crossover treatment in a prospective study was performed including 40 women with bilateral obstructed tubes and normal ovarian function, treated in 80 ovulation induction cycles using the long protocol. Twenty patients used nafarelin acetate 600 g/daily in their first cycle and received d-Trp6-LHRH, 0.5 mg/daily, in their following cycle. The other 20 women used decapeptyl in their first cycle and received nafarelin in the second.Results Estradiol suppression was achieved by both d-Trp6-LHRH and nafarelin at equal time intervals. The average total number of ampoules (P=0.0005) and the length of administration of hMG required for ovarian stimulation (P=0.0002) and the time interval between GnRHa initiation to oocyte retrieval (P=0.04) was significantly lower in nafarelin cycles. The number and the distribution between large and small follicles as well as the average number of oocytes retrieved did not differ between the two GnRH analogues.Conclusion Our results demonstrate that nafarelin acetate is comparable to d-Trp6-LHRH for temporary pituitary suppression used for controlled ovarian stimulation in IVF patients. However, using nafarelin ovarian stimulation was achieved with fewer ampoules of hMG, administered for a shorter period of time, thus with a lesser cost.  相似文献   
16.
The bioequivalence of two megestrol acetate formulations, 160-mg tablets and 160-mg sachets, was investigated in a single-dose, open-label, balanced-for-sequence cross-over study involving 12 advanced-cancer patients. The observed plasma megestrol-acetate time course obtained with both formulations was consistent with the literature data. The main source of variability in the pharmacokinetic parameters was intersubject variability; drug formulation played only a minor (and nonsignificant) role. The width of the 90% confidence interval of the areaunder-the-curve (AUC) ratio (sachets: tablets) computed according to Schuirmann (0.9–1.4) was mainly due to the presence of a single outlier, showing an AUC ratio of 2.7. The trend to higher bioavailability of the new formulation was not significant, especially as compared with the doseresponse data reported in the literature.  相似文献   
17.
Summary The use of the conventional combination oral contraceptives (containing ethinyl-estradiol and a progestin) is associated with reduced risk of ovarian and endometrial cancer. However, prolonged use of these pills before first term pregnancy apparently increases the risk of pre menopausal breast cancer. We propose that the pineal gland hormone melatonin, combined with a progestin, as a new and novel oral contraceptive combination might prevent breast cancer in long term users. This hypothesis is based on the assumption that women have a propensity to develop breast cancer which correlates with number of ovulatory cycles over their lifetime. In evolution, the phylogenetic point at which women became sensitive to breast cancer evolved at a transfer point of the mechanism of ovulation from seasonal ovulation, which is still common in many mammalian species, to the current human pattern of continuous ovulatory cycles. We suggest that melatonin/ovariansteroid contraceptive will restore the lost mechanism of endogenous anovulation, and thus, by preventing continuous epithelial breast cell proliferation, will reduce the risk of breast cancer in long-term users.  相似文献   
18.
Following subacute intoxication of rats with Pb-, Cu-, and Zn-salts (separately or in mixture) for 5 weeks, the chelating agent D-penicillamine was administered for 3 weeks. In the course of the 3-month experiment, lactate dehydrogenase (LDH) was estimated in serum and in cytoplasmic fraction of the kidney. Pb2+ treatment resulted in an increase of LDH activity, Cu2+ in a slight decrease, whereas Zn2+ had no effect, respectively. Mixture of these metals caused a significant rise in the enzymatic activity. Seven weeks after the stoppage of the administration of toxic substances, altered LDH activity, both in serum and in kidney returned to normal. D-penicillamine treatment was found to accelerate a restoration of the enzyme activity.In the experiments in vitro, Cu2+ inhibited significantly the kidney LDH activity, Pb2+ and Zn2+ being 100- and 400-times less efficient, respectively. Cu2+ inhibition was reversed by D-penicillamine, whereas inhibition of LDH by Zn2+ or Pb2+ was irreversible.  相似文献   
19.
预先咨询对妇女使用醋酸甲孕酮避孕停用率的影响   总被引:6,自引:0,他引:6  
目的:了解预先咨询对150mg醋酸甲孕酮(DMPA)作为3个月使用1次的长效避孕针的停用率的影响。方法:将421例受试者分为两组,204例在用药前和用药中对DMPA的激素作用和可能的副反应接受详细的咨询(强化组),217例接受一般性咨询(一般组)。每3个月随访1次,持续1年。观察停用率、常见的医疗事件和停用原因。结果:最常见的停用原因是月经改变,虽然强化组月经不规则发生率(39.7%)较一般组的(26.3%)高(P<0.01),但其停用率仍显著低于一般组,1年时累积停用率分别为11.3%(23/204)和42.4%(92/217)(P<0.0001)。无妊娠和严重的或不期望的医疗事件发生。结论:对预计的副反应作预先咨询,提高了DMPA可接受性。  相似文献   
20.
春根藤化学成分的研究(Ⅱ)   总被引:3,自引:0,他引:3  
目的 :探讨春根藤的化学成分。方法 :柱色谱分离 ,波谱及单晶X衍射分析鉴定结构。结果 :分离鉴定了8个化合物 ,为bauerenyl acetate(18) ,东莨菪素(19) ,liriodendrin(20) ,松脂醇 2-氧-β-D-葡萄糖苷(21) ,胡萝卜苷 (22) ,白瑞素 (23) ,七叶素(24)和七叶苷(25)。结论 :8个化合物均系首次从该植物中分得 ,化合物 20 ,21,23~25系首次从该属植物中分得 ,bauerenyl acetate为新的天然产物。  相似文献   
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