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大狼毒三萜类化学成分的研究   总被引:3,自引:0,他引:3  
曹东  苏亚伦  杨峻山 《药学学报》1992,27(6):445-451
自大戟科(Euphorbiaceae)植物大狼毒(Euphorbia nematocypha Hand—Mazz)根的乙醇提取物的苯溶解部分,经20%AgNO3硅胶层析,分离得到七个三萜类成分。根据光谱(IR,EIMS,1H—NMR和13C—NMR)和化学方法,确定其中一个化合物为新化合物,命名为大狼毒醇(nematocyphol,Ⅳa),其它化合物为已知物:印度荆芥醇乙酸酯(nepehinol acetate Ⅰ),日尔曼醇乙酸酯(germanicol acetate Ⅱ),大戟醇(euphol,Ⅲ),蒲公英醇(taraxasterol,Ⅴa),24-亚甲基环阿尔廷醇(24-methylenecycloartanol,Ⅴa)和印度荆芥醇(nepehinol,Ⅶa)。这些化合物均为首次从大狼毒中得到。  相似文献   
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Plantar defects are a challenge for the plastic surgeon; from 1984–1995 59 operations were performed in 57 patients. The radial forearm flap and the latissimus dorsi (LD) flaps were mainly used depending on the amount of tissue loss. Local flaps such as dorsalis pedis and instep flaps were used for smaller defects. The radial forearm flap is ideal in terms of thickness and stability for the sole but limited in its size. The LD flap is a safe procedure especially for severe injuries and osteitis, but has the disadvantage of being bulky and debulking procedures are frequently performed. For nerve reconstruction deep sensibility seems to be sufficient in order to obtain stable postoperative results. In this report the different operative methods are evaluated. Since 1991, the patients were monitored with static and dynamic foot pressure measurements and gait analysis to assess the postoperative result and prevent pressure ulcers, scar irritation and hyperkeratosis. Preoperative investigations may contribute to an optimal schedule for planning and stabilization of the operative regimen.  相似文献   
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Background: If cutaneous lymphoscintigraphy (CL) is accurate in predicting the draining lymph node basins at risk from primary axial melanomas, then regional metastases should only occur in those lymph node basins identified by CL. Methods: This study is a retrospective review of patients undergoing CL for primary axial melanomas from June 1, 1985, until June 31, 1992. Data retrieved included age, gender, number of basins identified, location of basins identified, management of basins, recurrence in lymphatics, development of distant disease, and long-term follow-up. Results: A total of 181 patients underwent elective LND, and 48 patients (27%) had melanoma in the nodes within the dissected basin. Of these 181 patients, seven developed nodal metastases as their site of first recurrence. All seven recurrences were seen at sites dissected or at sites indicated by CL, which the primary surgeon elected not to treat initially. Of the 116 patients observed, 16 (14%) developed lymph node metastases as their first site of recurrence. Fifteen of these 16 patients had their site of lymph node metastases predicted by CL. In this study, CL predicted 98.6% of all lymph node metastases. Conclusions: The high overall reliability of CL as demonstrated by long-term follow-up indicates that the information obtained by CL can be reliably used to guide intervention. Initial evaluation of patients with high-risk cutaneous melanomas at sites with ambiguous lymphatic drainage must include CL in order to determine the draining lymph node basins and to plan therapy. Presented at the 47th Annual Cancer Symposium of The Society of Surgical Oncology, Houston, Texas, March 17–20, 1994.  相似文献   
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In December, 1989, the Department of Transportation (DOT) in conjunction with the Federal Aviation Administration (FAA) mandated an extensive urine drug testing program for selected positions within the airline industry. At the end of 1 year we have tested 7,872 applicants under these rules, with a positive finding rate of 0.17%. We have also tested 32,157 applicants, including those applying for DOT-covered positions, with a positive rate of 2.82%. Considering only the two major drugs of abuse--marijuana and cocaine--we found the positive rate to be an order of magnitude greater than the rate discovered under the DOT program. We present these data together with a discussion of some of the possible reasons for this major disparity. We also present findings for barbiturates and benzodiazepines which are not tested under the DOT program, but which have safety implications related to the aviation industry.  相似文献   
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We have developed a reliable technique for labeling and examining neural structures in soft tissues associated with articular joints and have tested it in human wrist joints under various specimen-related conditions. The labeling protocol employs an immunohistochemical process with a panneuronal marker (PGP 9.5) as the primary antibody and Alexa Fluor 488 as the fluorescing secondary antibody. Imaging was done using a confocal laser scanning microscope, which produced exceptionally detailed three-dimensional images of nerve endings and transiting nerve fibers from thick sections of wrist joint ligaments obtained from human cadavers. The protocol provided a practical postmortem window for specimen acquisition and processing without significant apparent worsening of image quality. The images produced are resistant to fading with repeated exposure to a fluorescent light source, which gives many opportunities for observation. Background staining is minimal, producing high contrast labeling of target tissues, which, in turn, enhances image analysis.  相似文献   
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The growth at — 1.5°C of Lactobacillus delbrueckii, a meat spoilage organism, was evaluated on vacuum‐packaged lamb legs obtained from animals immunized against that organism. Growth was significantly lower than that on similarly treated legs obtained from non‐immunized lambs. These findings suggest that immunization against spoilage organisms may contribute toward increasing the chilled storage life of fresh meat.  相似文献   
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