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11.
12.
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   
13.
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   
14.
Addition polymerization of hydroxytelechelic polybutadiene (HTPB) with hexamethylene diisocyanate (HMDI) with a mole ratio NCO/OH = 0,8 in dilute solution of toluene as well as in bulk follows apparent 3rd order kinetics. The polymerization rates are twice as sensitive to temperature as in toluene, an effect which is attributed to intra- and/or intermolecular (OH, OH) auto-association. The three alcoholic functions in HTPB are catalyzed equally by dibutyltin dilaurate. Even with high excess of NCO, free alcoholic functions were found in the product. They were determined quantitatively in moulded polyurethane sheets from HTPB + HMDI and HTPB + 4,4′-methylenedi(phenyl isocyanate) which should be partially crosslinked:  相似文献   
15.
In depth study of low molecular weight poly(imide-amide)s (PIA) obtained by copolycondensation of 4,4′-methylenedi(phenyl isocyanate), trimellitic anhydride and benzoic acid by 1H and 13C NMR spectroscopy and size-exclusion chromatography allows the determination of their absolute number-average molecular weights M?n, abs. Viscosimetric measurements reveal that, dissolved in N-methyl-2-pyrrolidone, these low molecular weight PIAs should be semi-rigid because of the presence of very short crystalline chains. By using the semi-empirical Fox-Flory relation, the extrapolated glass transition temperature equals 300°C for high molecular weight.  相似文献   
16.
Two sensitive sandwich ELISAs based on monoclonal antibodies directed to native C6 and C7 allowed the detection and quantitation of these complement proteins in 20 out of 37 serum samples from individuals who had previously been classified as deficient in these proteins as assessed by immunochemical and/or functional assays. Furthermore, serum from four C6-deficient and one combined C6-/C7-deficient individual showed an increase in the terminal complement complex (TCC) and a decrease in native C6 and C7 after complement activation as assayed by specific ELISAs. Despite their (incomplete) deficiencies, these individuals therefore possess functionally active terminal complement proteins with respect to their ability to generate the TCC. As these individuals have no history of a susceptibility to neisserial infections, even low concentrations of functionally active C6 and C7 may provide sufficient protection against those micro-organisms whose destruction requires TCC formation.  相似文献   
17.
The presence of a damaged tube has been suggested in recent studies to have a negative effect on in-vitro fertilization (IVF) outcome. Performing bilateral salpingectomy prior to IVF to maximize pregnancy rates may also result in unnecessary surgery. This case is also an example of the occurrence of interstitial pregnancy after salpingectomy. This unusual type of ectopic pregnancy must be kept in mind when evaluating a patient suspected of a possible early abnormal gestation after assisted reproductive technolologies.   相似文献   
18.
In southern Vietnam, a four-year-old boy presented with severe diarrhea, followed by seizures, coma, and death. The cerebrospinal fluid contained 1 white cell per cubic millimeter, normal glucose levels, and increased levels of protein (0.81 g per liter). The diagnosis of avian influenza A (H5N1) was established by isolation of the virus from cerebrospinal fluid, fecal, throat, and serum specimens. The patient's nine-year-old sister had died from a similar syndrome two weeks earlier. In both siblings, the clinical diagnosis was acute encephalitis. Neither patient had respiratory symptoms at presentation. These cases suggest that the spectrum of influenza H5N1 is wider than previously thought.  相似文献   
19.
The usefulness of lysostaphin for the removal of cell-adherent and extracellular bacteria in assays performed to measure the intracellular killing of Straphylococcus aureus by granulocytes was investigated. The results showed that the adherence of lysosiaphin to the granulocyte surface is effectuated by a temperature-independent process and that bound lysostaphin is still microbicidal. Lysosiaphin also penetrates into the granulocytes by a temperature dependent process and kills ingested S. aureus intracellularly. Therefore, despite reports to the contrary in the literature, lysosiaphin is not a reliable agent for the removal of only extracellular S. aureus and should no longer be used in assays to determine the rate of intracellular killing by granulocytes.  相似文献   
20.
The personality of patients suffering from Parkinson's disease has been considered as the basis of a psychosomatic theory or more simply as a form of reaction. Between these two extremes the controversy continues and is modified by the use of dopaminergic agents. In this study, 30 patients suffering from parkinson's disease undergo a psychological examination and a M.M.P.I.; the results allow us to determine a pre-morbid obsessive personality coupled with agressivity and ambition. A transformation occurs with the arrival of illness; dependence, passivity, suggestibility evolve in a context where anxiety is relieved of all agressivity but acquires a depressive character. The people surrounding the patients play a part in this transformation. Moreover the pre-morbid characteristics of these patients remind the physician of H. Tellenbach's "typus melancholicus".  相似文献   
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