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21.
7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素的合成   总被引:1,自引:0,他引:1  
以6-取代-2-喹诺酮-3-乙酸为侧链,用CDI法和潘化酯法与7-ADCA,7-ACA,7-ACT,和7-ACD缩合,合成了16个新的7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素类化合物,通过溶媒转提,葡聚糖凝胶(Sephadex LH-20)柱层析及离心薄层层析分离精制,得到纯品。初步体外抑菌试验表明:新化合物对革兰氏阳性及某些阴性菌具有高度敏感性。大多数化合物对所试试验菌的抗菌活性与头孢唑啉和青霉素G钠相当,有些比它们还强。  相似文献   
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Human alkaline phosphatases extracted with butanol from liver, kidney and placenta, and from foetal and adult small intestine each contain fragments with molecular masses within the range of approximately 8 kDa to 20 kDa which can be removed by digestion with bromelain. However, in the case of adult intestine, this fragment (which is presumed to represent a membrane-binding domain) can only be demonstrated in tissue extracted immediately after removal at operation. Similar fragments are also present in foetal intestinal phosphatase in amniotic fluid, and in liver and bone alkaline phosphatases recovered from serum. Again, however, adult intestinal phosphatase from serum differs in the absence of the bromelain-sensitive fragment. These observations indicate differences in the ways in which intestinal and non-intestinal alkaline phosphatases gain access to the circulation, and also have implications for structural studies on intestinal phosphatase extracted post mortem from adult tissue.  相似文献   
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多索茶碱及其片剂的高效液相色谱分析   总被引:3,自引:0,他引:3  
多索茶碱及其片剂的高效液相色谱分析刘春胜,何秀峰,王云萍,谷士杰,周同惠(中国医学科学院、中国协和医科大学药物研究所,北京100050)多索茶碱(doxofylline)是用于治疗支气管哮喘合并支气管痉挛的慢性阻塞性肺部疾病的新一代黄嘌吟衍生物,其药...  相似文献   
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A controlled cross-over study in 12 Victorian public hospitals was performed to examine the power of marketing techniques in influencing prescribing. The targeted prescribing behaviour was the use of antibiotic prophylaxis in surgery, and the criteria for judging the appropriateness of therapy were its duration and timing, as are detailed in the fourth edition of the booklet Antibiotic guidelines. The first intervention was mounted in 1985 in six hospitals (two metropolitan teaching hospitals, one suburban general hospital and three rural hospitals), and six matched hospitals acted as control hospitals. One year later, the intervention was mounted in the six hospitals that previously had been the control hospitals. The interventional campaign consisted of material that was similar to that which is used by the pharmaceutical industry, including an "academic" representative. Its effect was assessed by audits that were performed before and after the first interventional campaign and again, one year later, after the second interventional campaign. The proportion of antibiotic courses that were assessed as satisfactory in terms of duration increased significantly after the first campaign in the hospitals where the intervention was mounted. No significant changes in prescribing occurred in the control hospitals. In the hospitals which were control hospitals in 1985, and in which the intervention occurred in 1986, the proportion of antibiotic courses that were assessed as satisfactory also increased significantly after the interventional campaign. A fall-off in performance occurred during the 12 months after the campaign in the 1985-interventional hospitals. Calculated cost savings more than outweighed the costs of the campaign. We conclude that inappropriate prescribing behaviour in hospitals can be modified successfully by educational marketing techniques.  相似文献   
29.
This research represents the first controlled treatment study of hypnosis and cognitive- behavioral therapy (CBT) of acute stress disorder (ASD). Civilian trauma survivors (N=87) who met criteria for ASD were randomly allocated to 6 sessions of CBT, CBT combined with hypnosis (CBT-hypnosis), or supportive counseling (SC). CBT comprised exposure, cognitive restructuring, and anxiety management. CBT-hypnosis comprised the CBT components with each imaginal exposure preceded by a hypnotic induction and suggestions to engage fully in the exposure. In terms of treatment completers (n=69), fewer participants in the CBT and CBT-hypnosis groups met criteria for posttraumatic stress disorder at posttreatment and 6-month follow-up than those in the SC group. CBT-hypnosis resulted in greater reduction in reexperiencing symptoms at posttreatment than CBT. These findings suggest that hypnosis may have use in facilitating the treatment effects of CBT for posttraumatic stress.  相似文献   
30.
OBJECTIVE: To investigate the association of hormone levels at menopause, lifestyle variables, and body composition with the predicted 10-year risk of a coronary event, calculated using the PROCAM scoring system, in a population-based sample of Australian-born, middle-aged women. DESIGN: A 9-year prospective study of 438 Australian-born women, who at baseline were aged 45 to 55 years and had menstruated in the prior 3 months. Interviews, fasting blood, and physical measurements were taken annually. The risk of an acute coronary event was calculated using the PROCAM scoring system (includes: age, low-density lipoprotein cholesterol, smoking, high-density lipoprotein cholesterol, systolic blood pressure, family history of premature myocardial infarction, diabetes mellitus, and triglycerides). RESULTS: Retention rate after 8 years of follow-up was 88% (n = 387). In women not using hormone therapy (HT): higher than average body mass index (BMI) (P < 0.001), BMI that increased (P < 0.005), lower than average estradiol levels (P < 0.005), estradiol levels that decreased (P < 0.001), and high free testosterone levels (P < 0.05) were associated with increased risk of a coronary event. There was a trend for high exercise frequency to be associated with a decreased risk (P < 0.07). After BMI and lifestyle variables were taken into account, use of HT did not have a significant effect on risk of a coronary event. CONCLUSION: In this longitudinal observational study of middle-aged Australian-born women, high BMI, an increase in BMI, high free testosterone, low estradiol, and a decrease in estradiol levels were the main determinants of increased risk of an acute coronary event, based on the PROCAM scoring system calculation. More frequent exercise tended to lower the risk.  相似文献   
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