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61.
Examination of Dracaena loureiri, a Thai medicinal plant possessing anti-bacterial activity, has led to the isolation of two new representatives, 1 and 2, of a rare skeleton of homoisoflavans. Proton assignments of the two isolates were aided by extensive 2D-homonuclear chemical shift correlation and nOe difference spectroscopy. Carbon assignments were completed through the utilization of simple and sensitive one-dimensional techniques such as selective population transfer via one-bond (CSCM 1D) and selective polarization transfer via long range coupling (selective INEPT) experiments. Conformational assignments were proposed through nOe difference spectroscopy and have been established by X-ray crystallography. The absolute configuration is proposed based on the octant rule and a biogenetic pathway for this type of homoisoflavan is briefly discussed.  相似文献   
62.
苦楝化学成份的研究   总被引:7,自引:0,他引:7  
从苦楝(Melia azedarach L.)果中分得苦楝新醇(Ⅰ),苦楝醇(Ⅱ)、苦楝酮(Ⅲ)、苦楝二醇(Ⅳ)、香草醛(Ⅴ)和香草酸(Ⅵ)。根据波谱(IR,MS,1HNMR,13CNMR)分析和理化常数测定,确定了它们的结构。其中苦楝新醇(Ⅰ)为新化合物,对菜青小虫有一定的拒食活性。  相似文献   
63.
Laparoscopic radical prostatectomy (LARP) has been accepted as first line therapy for clinically localized prostate cancer. Complications have been low and outcomes are comparable to that of open surgery with potential benefits including shorter hospital stay, less pain and quicker return to normal activity. Unexplained paralysis following LARP is a rare entity with no reported cases in the current literature. We report a case of complete motor paralysis following LARP. An extensive multidisciplinary evaluation did not definitively establish a diagnosis. Aggressive multimodality treatment led to a complete recovery. Our understanding of this phenomena with the possible etiology and treatment is discussed.  相似文献   
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When an ED prisoner/patient was shot, the unfortunate incident offered a number of lessons, even for a busy, seasoned emergency department with good security. These lessons, not the least of which was to think twice before removing both handcuffs, are worth sharing.  相似文献   
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目的:对比观察骨髓间充质干细胞移植前后脑梗死大鼠脑电图的变化。方法:实验于2002-09/12在解放军第三军医大学中心实验室及西南医院神经内科肌电图室完成。①实验分组:选取清洁级健康成年Wistar大鼠15只,随机数字表法分为干细胞移植组、模型对照组、假手术组,5只/组。②实验方法:另取2只健康幼年Wistar大鼠用于骨髓间充质干细胞的提取,联合采用密度梯度离心及贴壁法分离培养大鼠骨髓间充质干细胞,选取生长良好的1~3代细胞用于移植实验。干细胞移植组、模型对照组大鼠建立大脑中动脉栓塞模型。假手术组仅分离颈总动脉、颈外动脉和颈内动脉,不予结扎和放置线栓。造模后1周,干细胞移植组、假手术组大鼠行细胞移植,在立体定向仪定位下于脑梗死区(壳核)直接注射骨髓间充质干细胞悬液5μL,细胞浓度1×104μL-1,移植坐标为前囟前1.0mm,右旁开3.0mm,硬膜下5.0mm。模型对照组大鼠于相同部位注射等量不含细胞的磷酸盐缓冲液。③实验评估:采用脑电图机分别于造模前、造模后1周(移植前)、细胞移植后4周对各组大鼠进行脑电图检测。结果:15只大鼠均进入结果分析。①造模前基本节律为8~11Hz、15~30μV的α波,间或少量θ波,双侧对称。②造模后1周,假手术组异常率为0;模型对照组20%(1/5)轻度异常,80%(4/5)中度异常;干细胞移植组20%(1/5)轻度异常,60%(3/5)中度异常,20%(1/5)重度异常。③细胞移植后4周,假手术组脑电图恢复正常;模型对照组随术后时间的延长慢波有所减少,但仍可见到δ波、棘波、棘慢波的发放,至细胞移植后4周60%(3/5)轻度异常,40%(2/5)中度异常;干细胞移植组术后局限性慢波逐渐减少,基本节律全部恢复为α波,不对称的情况明显好转,至细胞移植后4周60%(3/5)轻度异常,以病灶侧局限性θ波较多为主,另外40%(2/5)基本正常。结论:动物实验显示骨髓间充质干细胞移植对脑梗死大鼠的脑电图背景节律有改善作用,一定程度上促进了神经系统功能的恢复。  相似文献   
68.
WH Visser  MD  ; RHM de  Vriend  MSc ; NHWM Jaspers  MSc  ; MD Ferrari  MD  PhD 《Headache》1996,36(8):471-475
Sumatriptan, notably after subcutaneous administration, is highly effective in the acute treatment of migraine in the majority of patients. The response is consistent within patients and over time. To determine risk factors for nonresponse to sumatriptan, we compared clinical characteristics. In responders and nonresponders and, within patients, between attacks with and without response. We found no differences at the strict level of significance (P<0.001 because of multiple comparisons), but only tendencies for differences (0.001相似文献   
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Radiation-induced red cell damage: role of reactive oxygen species   总被引:1,自引:1,他引:1  
BACKGROUND: Cellular blood components are irradiated to prevent graft- versus-host disease in transfusion recipients at risk for this syndrome. Because gamma radiation can result in the production of reactive oxygen species, the role of reactive oxygen species was investigated in radiation-induced red cell damage. STUDY DESIGN AND METHODS: Whole blood from normal donors was exposed to various doses of t-butyl hydroperoxide (0-1 mM) and/or to gamma-radiation (0-50 Gy). Oxidative damage was assessed by the extent of lipid peroxidation (measured by thiobarbituric acid-reactive substances [TBARS]) and hemoglobin oxidation. Fresh blood was divided into three parts-one initially irradiated and stored, another stored with portions irradiated weekly, and a third stored without irradiation. TBARS and hemoglobin oxidation were measured weekly. RESULTS: As expected, t- butyl hydroperoxide induced TBARS formation and hemoglobin oxidation in a dose-dependent fashion. The gamma-radiation not only increased hemoglobin oxidation and TBARS formation, but also enhanced the t-butyl hydroperoxide effect on red cells. Red cell storage increased TBARS generation and hemoglobin oxidation in a time-dependent fashion. When radiation was administered either initially or after weekly storage, TBARS production and hemoglobin oxidation were increased over that measured in unirradiated paired controls. CONCLUSION: Gamma radiation at clinically used doses increases lipid peroxidation and hemoglobin oxidation in human red cells. The effect of gamma-radiation is accentuated by blood storage and induces damage independent of time of storage.  相似文献   
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