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排序方式: 共有288条查询结果,搜索用时 15 毫秒
81.
石南藤、山蒟活性成分的分离和结构鉴定 总被引:4,自引:0,他引:4
已报道自山蒟及石南藤中分得海风藤酮(Ⅰ),denudatin B(Ⅱ),N-isobutyl-deca-trans-2-trans-4-dienamide(Ⅲ),本文继续报道自山蒟中分得一新木脂素,命名为山蒟素D(Ⅳ),X-衍射晶体结构测定为外消旋光学异构体。自石南藤分得Ⅳ的同系物,为新结构、命名为南藤素(Ⅴ),以及山蒟素C(Ⅵ),galgravin(Ⅶ),二氢毕拨明宁碱(Ⅷ)及巴豆环氧素(Ⅸ)。以上化合物皆首次自山蒟及石南藤中分得。以血小板活化因子(PAF)引起的血小板凝集实验测定活性,除Ⅲ,Ⅳ,Ⅶ,Ⅸ外皆有抑制活性。 相似文献
82.
大丁草中抗菌活性成分的研究Ⅳ 总被引:1,自引:0,他引:1
从秋季采收的菊科植物大丁草Gerbera anandria(L.)Sch Bip.全草中共分出十三种成分。本文报道其中三个新化合物的结构鉴定.它们分别是3,8-dihydroxy-4-methoxy-coumarin(ⅪⅩ),3,8-dihydroxy-4-methoxy-2-oxo-2 H-1-benzopyran-5-carboxylic acid(ⅩⅦ),和5,8-dihydroxy-7-(4-hydroxy-5-methyl-coumarin-3-)-coumarin(ⅩⅪ)。 相似文献
83.
争光霉素A6和它在争光霉素复合物的地位 总被引:8,自引:0,他引:8
争光霉素A5已鉴别为Bleomycin A6,在争光霉素复合物中所占比例一般在10%左右,在某些批样中可高达15%以上。文献报告Bleomycin A6在天然产的Bleomyein复合物中只有痕量。通过向发酵培养基中加入特定组分的末端胺可大大提高其特定组分在复合物中的含量比而其它组分的产生则不同程度地被抑制。但Bleomyein A6例外,即使向培养基中加入其末端胺精胺(0.3mg/ml),在所产生的复合物中大大增多的组分是Bleomyein A6,而Bleomycin A6仍只有痕量。这表明争光霉素产生菌有和Bleomycin产生菌明显不同的特点。 相似文献
84.
85.
高效液相色谱法测定血浆中醋氯芬酸及其在犬体内药代动力学 总被引:7,自引:0,他引:7
建立了HPLC法同时测定家犬血浆中的醋氯芬酸及其主要代谢物的浓度。此法简便易行,精密度好,方法回收率91.3%~96.9%,日内、日间RSD为3.69%~8.13%,血药浓度在0.050~51.2μg·mL-1范围内呈线性关系,相关系数0.9998,当S/N≥3时,最小检测浓度为10ng·mL-1。此法可同时测定醋氯芬酸及其在体内的主要代谢物。醋氯芬酸po吸收迅速,给药后约12min即达血药浓度峰值,其药—时曲线符合二室模型,T1/2α仅为2.5min左右,T1/2β约为137min,代谢物约在110min达到血药浓度峰值,峰浓度为3.20μg·mL-1,T1/2β约为140min。 相似文献
86.
87.
RS McLeod BG Wolff AH Steinhart PW Carryer K O'Rourke DF Andrews JE Blair JR Cangemi Z Cohen JB Cullen RG Chaytor GR Greenberg NM Jaffer KN Jeejeebhoy RL MacCarty RL Ready LH Weiland 《Gastroenterology》1997,113(6):1823-1827
BACKGROUND & AIMS: The aim of this study was to determine the risk of endoscopic/radiological recurrence of Crohn's disease postoperatively and the long-term outcome. METHODS: A randomized placebo-controlled trial was performed to determine the effectiveness of mesalamine in preventing recurrent Crohn's disease postoperatively. Patients in the control group were examined endoscopically/radiologically before entry into and annually during the trial. Findings were classified as minimal or severe. RESULTS: There were 76 patients (49 men and 37 women; mean age, 37.1 +/- 13.2 years). Fifty (61.7%) had terminal ileal resections. Overall, 55 endoscopic/radiological recurrences were observed in 51 patients (67.1%). Expressed actuarially, the recurrence rate was 27.5% at 1 year (95% confidence interval [CI], 15.8%-37.6%), 60.8% at 2 years (95% CI, 46%-71.3%), and 77.3% at 3 years (95% CI, 62.7%-86.3%). Nineteen (37%) were symptomatic and 12 (24%) were initially asymptomatic but later became symptomatic (mean, 13.0 +/- 8.8 months), whereas 20 (39%) remained asymptomatic (mean, 16.9 +/- 17.4 months). Patients with severe endoscopic/radiological disease were significantly more likely to be or become symptomatic than those with minimal disease (23 of 32 vs. 8 of 19, respectively; P = 0.0437). CONCLUSIONS: This study suggests that postoperative endoscopic/radiological recurrences occur later than previously reported. Furthermore, many of these patients, especially with minimal disease, will remain asymptomatic. (Gastroenterology 1997 Dec;113(6):1823-7) 相似文献
88.
Ronald M van Dam Toine M Lodewick Maartje AJ van den Broek Mechteld C de Jong Jan Willem Greve Rob LH Jansen Marc HA Bemelmans Ulf P Neumann Steven WM Olde Damink Cornelis HC Dejong 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(6):550-559
Background
Currently, resection criteria for colorectal cancer liver metastases (CRCLM) are only limited by remnant liver function. Morbidity and survival after a partial hepatectomy with limited or extended indication criteria were compared.Methods/Design
Between 1991 and 2010, patients undergoing a liver resection for CRCLM with limited (n = 169) or extended indication criteria (n = 129) were retrospectively identified in a prospectively collected single-centre database. Limited indication criteria were defined as less than three unilateral, not centrally located liver metastases in the absence of extra hepatic metastases. The extended criteria were only limited by predicted remnant liver volume and patients fitness. Data on co-morbidity, resection margin, short- and long-term morbidity, disease-free (DFS) and overall survival were compared.Results
Patients with limited indications had less major complications (19.5% vs. 33.1%, P < 0.01), longer overall survival of 68.8 months [confidence interval (CI) 46.5–91.1] vs. 41.4 months (CI 33.4–49.0, P ≤ 0.001) and longer median DFS of 22.0 months [confidence interval (CI) 15.8–28.2] vs 10.2 months (CI 8.4–11.9, P < 0.001) compared with the extended indication group. Cure rates, defined as 10-year DFS, were 35.5% and 15.8%, respectively. Fewer patients in the extended indication group underwent an R0 resection (92.9% vs. 77.5%, P < 0.001). Only 17% of all R1 resected patients had recurrences at the transection plane.Conclusion
A partial hepatectomy for CRCLM with extended indications seems justified but is associated with higher complication rates, earlier recurrence and lower overall survival compared with limited indications. However, the median 5-year survival was substantial and a cure was achieved in 15.8% of patients. 相似文献89.
WANG Guo Zhong RU Xin DING Li Hua LI He Qun 《World journal of gastroenterology : WJG》1998,4(2):169-170
ShorttermefectofSalviamiltiorhizaintreatingrataceticacidchronicgastriculcerandlongtermefectinpreventingrecurenceWANGGuoZho... 相似文献
90.
SH Kleinman ; JC Niland ; SP Azen ; EA Operskalski ; LH Barbosa ; AI Chernoff ; VM Edwards ; BA Lenes ; GJ Marshall ; GJ Nemo ; et al. 《Transfusion》1989,29(7):572-580
The Transfusion Safety Study (TSS) and the National Heart, Lung, and Blood Institute (NHLBI) established a repository of approximately 200,000 sera from blood donors in late 1984 and early 1985. Collections were made in the four metropolitan areas with the highest prevalence of AIDS. Retrospective testing showed an overall anti-HIV-1 prevalence of 16 cases per 10,000 donations. In this study, the predictive value of a negative initial enzyme-linked immunoassay was estimated from both quality control specimens and the rescreening of 13,461 sera to be greater than 99.99 percent with respect to technical error. Among anti-HIV-1-positive persons, there was a 1.3- to 1.5-fold excess of first-time donors. The anti-HIV-1 prevalence among donors showed that infection was more common among young men than suggested by national reporting of AIDS cases. Anti-HIV-1 prevalence varied among the four metropolitan areas less than did reported AIDS cases, but, by 1987, the differences in the latter had decreased. Anti-HIV-1 prevalence in collection areas outside of the four major cities differed much more widely than that among the cities themselves. The TSS/NHLBI Donor Repository will remain available for the indefinite future for further evaluation of screening procedures for HIV-1 and other viruses for which transfusion is found to be an important route of transmission. 相似文献