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991.
S Yao  K Ying  Z Li  L Shen 《中国医疗器械杂志》1999,23(4):207-9, 238
A spot weld & heating treatment tri-uses device based on modern mechanical-electric technique, was developed for dental spot weld, stainless steel orthodontic wire heating-reversion and Ni-Ti orthodontic wire heating-overload metamorphism. The device will be very helpful instrument in orthodontic clinic. The paper not only described the operating methods of the device, but also discussed the Performance-improved principles of stainless steel orthodontic wire and the principles of heating overload metamorphism of Ni-Ti orthodontic wire.  相似文献   
992.
该文报告23例胰腺假性囊肿,根据病期、囊肿大小、部位选择治疗方法,其中非手术治疗5例,外引流1例,内引流14例,囊肿切除术3例。结果:无手术死亡,非手术治愈5例,外引流术后胰瘘1例,囊肿切除术后复发1例,内引流术后无严重并发症出现。我们认为急性囊肿应观察6周,有些病例有自行消散的可能,慢性囊肿一经确诊即可行内引流治疗,内引流是目前较理想的有效手术方式  相似文献   
993.
Dawei  Peng  Shujun  Zeng 《眼科学报》1999,15(1):51-55
Purpose: To observe the inhibitory action of homoharringtonine liposome during the healing process of wounds in the filtering sitesMethods: posterior sclerectomies were performed in 14 rabbits. Postoperatively one eye of each rabbit received subconjunctival injections of HH liposome and fellow eye received saline injection in a randomized masked fashion.Results; Fourteen days after operation the IOP of experimental eyes reduced significantly (P < 0.01) as compared with the controlled eyes, and the number of remaining filtering blebs increased noticeably (P< 0.05). Pathohistological examination revealed that the number of fibroblasts per square micron in the filtering sites and the thickness of the scars in the center of the filtering sites of the experimental eyes were less than those of the controlled eyes. No serious ocular toxic and side effects were found.Conclusion : This experiment suggests that homoharringtonine liposome can markedly inhibit the scar formation of filtering sites after glaucoma fi  相似文献   
994.
目的 评价白内障不同的手术切口对术后视力恢复的影响。方法 对186 只眼老年性、并发性、发育性和无角膜瘢痕的外伤性白内障行ECCE(CCC) 加IOL。切口为11 m m ,隧道6 m m 及反眉状5 .5 m m 巩膜切口,手术后1 wk ,1 m o ,3 m o 进行视力和屈光检查与比较。结果 随着手术切口的缩小和手术切口的改进,角膜散光明显减少,视力明显提高。结论 提示反眉状隧道式白内障摘出术IOL 术具有有效控制术后散光,全面重建视功能的优点  相似文献   
995.
远志皂苷的降压作用及其机制   总被引:6,自引:0,他引:6  
研究无志皂苷对血压的影响。方法:大鼠麻醉后左颈总动脉记录平均动脉压,尾袖法测定清醒大鼠和肾性高血压大鼠收缩压。结果:TS2,4,8mg.kg^-1iv,20和40mg.kg^-1ig分别使MAP降低31%,37%,50%,21%和31%,40mg.kg^-1ig使清醒大鼠和RVHR的血压分别于给药后60和90min降低38.0%和26.8%,并至少维持2和3h。  相似文献   
996.
目的:探讨一氧化氮(NO)及氧自由基(OFR)在新生儿缺氧缺血性脑病(HIE)中的作用及意义。方法:取正常及HIE急性期新生儿的静脉血制备成血浆,采用硝酸还原酶法测定NO的含量,用化学比色法测定MDA的含量及SOD的活力,用ELISA法测定NSE水平。结果:HIE急性期新生儿血浆NO、MDA及NSE水平较正常对照组新生儿均明显增高(均P<0.01);而SOD活力则明显降低(P<0.01)。结论:NO和OFR与新生儿HIE的发病机制有关。  相似文献   
997.
Sertraline and fluoxetine have different pharmacologic and pharmacokinetic profiles which may be of clinical relevance in the determination of response in different subtypes of depression. A randomized, double-blind, 6-week study comparing sertraline (50-100 mg/day) with fluoxetine (20-40 mg/day) in 286 outpatients with major depression, who had demonstrated comparable efficacy and tolerability for the two drugs, was analysed by subgroups of patients at baseline with melancholia, severe depression, single depressive episode, multiple depressive episodes, high anxiety, low anxiety, psychomotor retardation and psychomotor agitation. Multiple logistic regression with regressors including treatment-by-subgroup variables revealed that, within certain subgroups, the efficacy might differ substantially from that of the whole treatment group. However, the only treatment-by-subgroup interaction term that was significant was anxiety (P < 0.05). There was no evidence of interaction in single or recurrent episode subgroups, and these were not included in subsequent analyses. Subsequent two-sample statistical comparison tests of response (i.e. Hamilton Depression Scale reduction > or = 50%) rates at study endpoint between treatment groups demonstrated that patients with melancholic depression and those with symptoms of psychomotor agitation yielded a significantly greater proportion of responders with sertraline compared to fluoxetine (P < 0.05). Response rates in sertraline- and fluoxetine-treated patients, respectively, were: overall study 59%, 51%; melancholia 59%, 44%; severe depression 59%, 41%; low anxiety 71%, 55%; high anxiety 47%, 48%; psychomotor retardation, 48%, 46%; and psychomotor agitation 62%, 39%. Multiple logistic regression adjusting for possible confounding factors, that included a treatment by anxiety interaction term, also led to similar findings. In particular, the analysis showed that significant differences existed in favour of sertraline in patients with low anxiety in the melancholia and severe depression subgroups (P < 0.05), indicating that these characteristics predicted a superior response to 6 weeks of treatment with sertraline relative to fluoxetine. Sertraline also demonstrated advantages over fluoxetine on parameters such as sleep and weight disturbance in severely depressed patients, and sleep disturbance, weight, cognitive disturbance and retardation in melancholic patients.  相似文献   
998.
BACKGROUND: Spearmint is commonly used as an antispasmodic and as a flavouring in several medications including antacids. It can produce heartburn, presumably by lowering lower oesophageal sphincter (LES) tone, but the mechanism has not previously been objectively examined. AIM: To study the effect of spearmint on LES function, acid reflux and symptoms. METHODS: In healthy volunteers, a Dent Sleeve and a pH electrode were placed in the distal oesophagus. They were then given spearmint either in a flavouring (0.5 mg), or a high (500 mg) dose, or a placebo, using a double-blind randomized crossover design. LES pressure, oesophageal pH and symptoms were recorded for 30 min before and after administration. RESULTS: LES pressure was not affected by spearmint, either high dose (19.6 vs. 16.0 mmHg), flavouring dose (20.2 vs. 19.8 mmHg) or placebo (20.5 vs. 19.2 mmHg, all N.S.). There were no differences in reflux occurrence following high dose (mean = 0.65 vs. 0.85 episodes), low dose (0.4 vs. 0.5 episodes) or placebo (0.7 vs. 1.10 episodes, all N.S.). There was a significant increase in mean symptom scores following high-dose spearmint (0 vs. 0.35, P = 0.03), but not low dose (0 vs. 0.2) or placebo (0 vs. 0.5, both N.S.). One subject reported symptoms with placebo, one with low dose, and six with high dose; all without increased reflux episodes or decreased sphincter pressure. CONCLUSION: Spearmint has no effect on LES pressure or acid reflux. Flavouring doses of spearmint do not produce more symptoms than placebo while high doses can be associated with symptoms, presumably from direct mucosal irritation but not reflux.  相似文献   
999.
药流与负压吸宫法的效果和可接受性研究   总被引:5,自引:1,他引:4  
研究的目的:比较RU486/Cytotec药物和负压吸宫术两种流产方法的效果,以及医学的和个人的可接受性.对象为通过咨询,介绍两种流产方法后,让对象自愿选择而组成.年龄在20~34岁.药物组100例,闭经35~42天,第1天口服RU486 600mg,第3天服Cytotec(PGE1)0.4mg,第17、43天回医院随访.手术组100例,闭经≤56天,负压吸宫术后第14、43天回医院随访.结果:完全流产率药物组为89%,手术组为100%.对象选择这两种流产方法的主要原因:药物组94%的人认为痛苦少,手术组的55%认为手术快、节省时间,而且手术同时可取出或放置宫内节育器(占45%).结论:RU486/Cytotec药物流产和负压吸宫术在各自适合的人群中都具有高度的可接受性.两种方法各具优缺点,不能相互取代,二者相辅相成,取长补短,将使终止妊娠的措施更为安全  相似文献   
1000.
Transforming growth factor-beta (TGFsZ) is a potent regulator of cellular growth and immune function. The authors studied ocular histology and endotoxin-induced uveitis in a TGF-sZ(1) transgenic (Tg) murine model. TGF-sZ(1) Tg mice were generated by micro injecting a gene constructed by fusing the mouse albumin enhancer/promoter and porcine TGF-sZ(1) cDNA. The eyes of Tg mice from two to 14 weeks of age were studied histologically. Tg mice, two to five weeks of age exhibited mild fragmentation of the lens fibers and retinal edema. No pathology was found from six to ten weeks of age, however, a progressive increased frequency of cataract was observed from 11 to 14 weeks of age. Plasma TGF-sZ(1) levels were much higher in Tg mice than age-matched wild type control littermates (wt). Endotoxin-induced uveitis (EIU) in six-to eight-week-old Tg and wt mice was induced by footpad injection of lipopolysaccharide (LPS). Mice were euthanized 24 hr after LPS injection, the eyes were collected for histology and serum assayed for IL-6 and TGF-sZ(1). There was a decrease in the mean numbers of infiltrating cells in Tg mice compared to wt mice. Serum IL-6 and TGF-sZ(1) were much higher in Tg mice. The authors concluded that expression of the TGF-sZ(1) transgene in the eyes may have effect on lens growth. Overexpression of TGF-sZ(1) results in little or no effect on the development of EIU.  相似文献   
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