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101.
白首乌化学成分的研究   总被引:4,自引:0,他引:4  
自白首乌主要品种耳叶牛皮消(Cynanchum auriculatum Royle ex Wight)根中首次分得三个已知甾体酯型甙元:告达亭(caudatin),开德甙元(kidjolanin),萝藦甙元(Metaplexigenin)和一种新的二苯酮衍生物(Ⅳ),经光谱分析推定其结构为2,6,2′,5′-四羟基,3-乙酰基,6′-甲基二苯酮,命名白首乌二苯酮。  相似文献   
102.
Over a 1-year period the use of a pour plate in detecting significant septicaemias due to bacteria and fungi was evaluated and compared with a conventional broth blood culture system. Of 207 significant bacterial blood culture isolates only 113 (56%) were detected by the pour plate. However, three out of four candidaemias were detected by the pour plate method alone. Despite its low positivity rate, the pour plate is cheap and allows for early detection of bacteraemia and candidaemia.  相似文献   
103.
白首乌化学成分的研究   总被引:11,自引:0,他引:11  
自白首乌主要品种耳叶牛皮消(Cynanchum auriculatum Royle ex Wight)根中首次分得三个已知甾体酯型甙元:告达亭(caudatin),开德甙元(kidjolanin),萝藦甙元(Metaplexigenin)和一种新的二苯酮衍生物(Ⅳ),经光谱分析推定其结构为2,6,2′,5′-四羟基,3-乙酰基,6′-甲基二苯酮,命名白首乌二苯酮。  相似文献   
104.
柳枫  廖松生 《药学学报》1989,24(5):372-375
本文用DSC和激光拉曼光谱研究抗癌药物足叶乙甙(4-去甲基表鬼臼毒素-β-D-乙叉吡喃葡萄糖甙,简称VP 16-213)与二棕榈酰磷脂酰胆碱(DPPC)脂质体的作用。VP 16-213分子掺入DPPC脂质体双层中,不但使相转变温度向高温移动,而且吸热峰的半高宽度随VP 16-213浓度增加而变宽。其Raman光谱在频率2850 cm~(-1)处的C-H键对称伸缩振动亦随着药物浓度增加而减弱。这些结果表明VP 16-213分子是定域在脂双层中DPPC分子链的C_1~C_9亚甲基区域,使脂质体的有序性提高而流动性降低。  相似文献   
105.
106.
Raul Zamora-Ros  Valerie Cayssials  Mazda Jenab  Joseph A. Rothwell  Veronika Fedirko  Krasimira Aleksandrova  Anne Tjønneland  Cecilie Kyrø  Kim Overvad  Marie-Christine Boutron-Ruault  Franck Carbonnel  Yahya Mahamat-Saleh  Rudolf Kaaks  Tilman Kühn  Heiner Boeing  Antonia Trichopoulou  Elissavet Valanou  Effie Vasilopoulou  Giovanna Masala  Valeria Pala  Salvatore Panico  Rosario Tumino  Fulvio Ricceri  Elisabete Weiderpass  Torkjel M. Sandanger  Cristina Lasheras  Antonio Agudo  Maria-Jose Sánchez  Pilar Amiano  Carmen Navarro  Eva Ardanaz  Emily Sonestedt  Bodil Ohlsson  Lena Maria Nilsson  Martin Rutegård  Bas Bueno-de-Mesquita  Kay-Thee Khaw  Nicholas J. Wareham  Kathryn Bradbury  Heinz Freisling  Isabelle Romieu  Amanda J. Cross  Paolo Vineis  Augustin Scalbert 《European journal of epidemiology》2018,33(11):1063-1075
Polyphenols may play a chemopreventive role in colorectal cancer (CRC); however, epidemiological evidence supporting a role for intake of individual polyphenol classes, other than flavonoids is insufficient. We evaluated the association between dietary intakes of total and individual classes and subclasses of polyphenols and CRC risk and its main subsites, colon and rectum, within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. The cohort included 476,160 men and women from 10 European countries. During a mean follow-up of 14 years, there were 5991 incident CRC cases, of which 3897 were in the colon and 2094 were in the rectum. Polyphenol intake was estimated using validated centre/country specific dietary questionnaires and the Phenol-Explorer database. In multivariable-adjusted Cox regression models, a doubling in total dietary polyphenol intake was not associated with CRC risk in women (HRlog2?=?1.06, 95% CI 0.99–1.14) or in men (HRlog2?=?0.97, 95% CI 0.90–1.05), respectively. Phenolic acid intake, highly correlated with coffee consumption, was inversely associated with colon cancer in men (HRlog2?=?0.91, 95% CI 0.85–0.97) and positively associated with rectal cancer in women (HRlog2?=?1.10, 95% CI 1.02–1.19); although associations did not exceed the Bonferroni threshold for significance. Intake of other polyphenol classes was not related to colorectal, colon or rectal cancer risks. Our study suggests a possible inverse association between phenolic acid intake and colon cancer risk in men and positive with rectal cancer risk in women.  相似文献   
107.
联合应用心痛定与克甫定对100例高血压降压疗效和冠心病危险因素的影响观察。用药七天后,总有效率93%,(P<0.01)。81%的患者服药后2—4天就能稳定在下降后的水平。服药后三大常规,肝肾功能无异常发现,血电解质,血尿酸及BUN不受影响。血糖明显降低(P<0.01),总胆固醇(TC)和甘油三脂(TG)降低,低密度脂旦白胆固醇(LDL—ch)降低和高密度脂旦白胆固醇(HDL—ch)升高非常显著(P<0.01)对心功能有良好的改善,血浆肾素(PRA)活性升高,而血管紧张素Ⅱ(AngⅡ)及醛固酮(PAC)降低。服药前后心率无明显变化(P>0.05)。无发现明显和严重副作用。是治疗高血压较理想的配伍方法。  相似文献   
108.
BACKGROUND: S100A6 and S100A2 are members of the S100 family of calcium binding proteins, which are down regulated in prostate cancer, however the molecular mechanism(s) underlying their loss of expression is unknown. METHODS: The promoter and exon 1 region of the S100A6 and S100A2 genes was sequenced in bisulfite modified DNA from non-malignant, benign prostatic hyperplasia (BPH), malignant and metastatic prostate tissues and in cell lines. Immunohistochemistry was performed to correlate S100A2 expression with methylation status. RESULTS: S100A6 methylation was absent or occurred at isolated sites in 14/14 cases of non-malignant epithelium and 5/5 cases of BPH tissues, whereas methylation was seen in 14/27 (52%) cases of prostatic cancer (P<0.0001), 2/2 cases of metastatic cancer and in the CWR22 prostatic cancer xenograft. Critical CpG sites within the S100A2 promoter were methylated in LNCaP, LNCaP-LN3, and CWR22 cells but not in Du145, PC3 or BPH45 cells. In tissues, S100A2 methylation was seen in 32/34 (94%) cases of adenocarcinoma and 5/5 cases of metastatic cancer. However, S100A2 methylation was also seen in 9/12 (75%) cases of non-malignant tissues and in 5/5 cases of BPH. Immunostaining, showed absent S100A2 expression all 41 cases of prostatic cancer, whereas staining was seen in the basal cells of non-malignant epithelium. CONCLUSIONS: Loss of S100A6 and S100A2 proteins is frequent in human prostatic cancer. A major mechanism underlying the loss of S100A6 expression appears to involve promoter hyper-methylation. However, mechanisms other than methylation of the known promoter are involved in silencing S100A2 in the prostate.  相似文献   
109.
110.
Hypnosis is practiced by a wide variety of professionals and lay people. The consumer typically has little information on which to base a decision about the utilization of a hypnotist's services. Although there is currently little legal regulation of hypnosis, there are many associations of hypnotists that have a variety of requirements for membership. A survey of all hypnotists' associations that could be contacted in the major cities of the United States was conducted in order to describe the method and degree of regulation of hypnotists through membership in the associations. In addition, an overview of the qualities of associated hypnotists were described in terms of their practice of hypnosis, their education and training, and the titles they used. Recommendations are made for assuring quality control in the use of hypnosis.  相似文献   
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