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81.
Ten monomeric indole alkaloids have been identified from the roots of KOPSIA OFFICINALIS. Four of them are known: (-)-kopsinine 1, (+)-5,22-dioxokopsane 2, (-)-tetrahydroalstonine 4, and (-)-quebrachamine 3; and six are new: (-)-isoeburnamine 5 (enantiomer of the known alkaloid (+)-isoeburnamine), (-)-N-methoxycarbonyl-12-methoxykopsinaline 7, (-)-N-methoxycarbonyl-11,12-methylenedioxy kopsinaline 8, (-)-N-methoxycarbonyl-11,12-dimethoxykopsinaline 9, (-)-11,12-methylenedioxykopsinaline 10, and (-)-12-methoxykopsinaline 11. 相似文献
82.
双环醇抗病毒与保护肝细胞作用的动态观察和分析 总被引:8,自引:0,他引:8
目的:探讨双环醇抗病毒机制,为进一步研究和开发双环醇打下理论基础。方法:通过2.2.15细胞与双环醇混合培养,观察血清丙氨酸氨基转移酶(ALT)、血清门冬氨酸氨基转移酶(AST)用药后与HBsAg,HBeAg,乙型肝炎病毒中DNA(HBV—DNA)之间的动态变化,定量逆转录PCR(RT—PCR)观察CTAT—1变化;临床实验中,患口服双环醇,每2周观察血清HBV—DNA与ALT,AST动态变化。结果:细胞模型实验中,随着双环醇与2.2.15细胞混合培养时间延长,HBsAg,HBV—DNA滴度逐渐降低,而培养上清ALT,AST无明显变化,细胞内稳定高水平表达STAT—1的mRNA;临床实验发现,以干扰素α为对照,患血清ALT,AST可以随着HBV—DNA水平降低而下降,但未发现患血清ALT,AST有一过性升高。结论:双环醇在发挥肝细胞保护作用的同时.还可能通过非细胞溶解性机制清除乙型肝炎病毒。 相似文献
83.
84.
Temperature and Daily Mortality in Shanghai: A Time-series Study 总被引:10,自引:2,他引:10
Objective To investigate the association between temperature and daily mortality in Shanghai from June 1, 2000 to December 31,2001. Methods Time-series approach was used to estimate the effect of temperature on daily total and cause-specific mortality. We fitted generalized additive Poisson regression using non-parametric smooth functions to control for long-term time trend, season and other variables. We also controlled for day of the week. Results A gently sloping V-like relationship between total mortality and temperature was found, with an optimum temperature (e.g.temperature with lowest mortality risk) value of 26.7℃ in Shanghai. For temperatures above the optimum value, total mortality increased by 0.73% for each degree Celsius increase; while for temperature below the optimum value, total mortality decreased by 1.21% for each degree Celsius increase. Conclusions Our findings indicate that temperature has an effect on daily mortality in Shanghai, and the time-series approach is a useful tool for studying the temperature-mortality association. 相似文献
85.
Lee SH Huang JW Hung KY Leu LJ Kan YT Yang CS Chung Wu D Huang CL Chen PY Chen JS Chen WY 《Artificial organs》2000,24(11):841-844
A multicenter collaborative study was performed to investigate the prevalence of abnormal blood contents of 6 trace metals, copper (Cu), zinc (Zn), aluminum (Al), lead (Pb), cadmium (Cd), and mercury (Hg), in hemodialysis (HD) patients and to analyze their relationship with the medications, such as CaCO3, Ca acetate, Al containing phosphate-binding agents, 1,25-dihydroxy vitD3, 1-hydroxy vitD3, and erythropoietin (EPO), as well as hematocrit level, by chi-square statistics. From 6 medical centers in Taiwan, we included 456 patients in maintenance HD for more than 4 months for this study, and they had continued the previously mentioned medications for at least 3 months. Blood samples were collected before initiating HD, and atomic absorption spectrophotometry was used to measure plasma levels of Cu, Zn, and Al as well as whole blood levels of Pb, Cd, and Hg. Three hundred seventy-five (78%) of the HD patients had low plasma Zn levels, that is, <800 microg/L, and the mean (+/-SD) concentration was 705.8 (+/-128.23) microg/L in all subjects. One hundred forty-one (31%) of the HD patients had high plasma Al, that is, >50 microg/L, and the mean (+/-SD) was 44.30 (+/-28.28) microg/L in all subjects. Three hundred thirty-three (73%) of the dialysis patients had high Cd levels, that is, >2.5 microg/L, and the mean (+/-SD) was 3.32 (+/-1.49) microg/L in all subjects. The majority of HD patients had normal blood levels of Cu, PB, and Hg. Only 21 (4. 6%), 5 (1.1%), and 3 (0.06%) patients had elevated blood levels of Cu, Pb, and Hg, respectively. Their mean (+/-SD) blood concentration of Cu, Pb, and Hg were 1,049.78 (+/-233.25) microg/L, 7.45 (+/-3.95) microg/dL, and 3.17 (+/-25.56) microg/L, respectively. Three patients had elevated plasma Hg concentrations, that is, 546, 12.6, and 24.0 microg/L, respectively. In the 152 normal healthy age and sex matched control group, the blood levels of Al, Cd, and Pb were all significantly lower than the HD patients. However, the levels of Cu and Zn were higher in the control group. The Hg level was not significantly different in both groups. There was no statistical difference between patients with normal and abnormal blood levels of trace metals in various medications except Al containing phosphate binder. The Al containing phosphate binder users had significantly higher plasma Al levels (54.71 +/- 26.70 versus 41.15 +/- 28.03 microg/L, p < 0.001) and hematocrit levels (29.61 +/- 4.61 versus 27. 81 +/- 3.91, p < 0.0005). There was no statistical correlation between erythropoietin (EPO) dose and hematocrit level in these patients. In conclusion, the blood level of trace metals of these HD patients except Al was not related to their medications. However, caution must be exercised in interpreting this result as dose and duration of medication; efficiency of HD and water treatment may play an important role. Otherwise, environmental factors, diet, and the aging process may contribute to the trace metal burden in uremia. Thus, Zn and Cu are abundant in seafood, and Cd is abundant in contaminated plants such as rice. 相似文献
86.
87.
Toru Sugiyama Takashi Nishida Akio Kataoka Kan Komai Naofumi Ookura Toshio Oobuchi Michiaki Yakushiji 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(2):92-96
Background We investigated retrospectively the records and tissue samples of patients with primary ovarian transitional cell carcinoma
to determine clinical and pathologic features.
Methods The records of 3 patients with ovarian transitional cell carcinoma were reviewed using data from several imaging techniques:
transvaginal ultrasound, computed tomography, and magnetic resonance imaging. We also determined levels of several tumor marker
molecules; and the level of carbohydrate antigen 125 (CA 125), was examined by means of immunohistochemistry.
Results The tumors of 2 patients were classified as pure trnasitional cell carcinoma; in the remaining patient, as predominantly transitional
cell carcinoma. All tumors were bilateral, and 2 of the 3 tumors formed solid masses. Areas of irregular high intensity signals
were seen in magnetic resonance images of the solid parts of the tumors. All 3 tumors tested positive for CA 125; histochemical
expression was confined to the tumor cell membrane and/or the cytoplasm in all cases. The tumors of all 3 patients tested
negative for carcinoembryonic antigen (CEA), and second-look laparotomies did not reveal any residual neoplasms in any of
the patients. The patients have been in a disease-free state for 34, 42, and 14 months, respectively.
Conclusion Our results suggest that transitional cell carcinomas tend to arise bilaterally and to form solid tumors. Magnetic resonance
imaging was a useful diagnostic modality in these cases. Transitional cell carcinoma was characterized by the presence of
CA 125 and the absence of CEA. 相似文献
88.
Obstetric outcome in 232 ovum donation pregnancies 总被引:3,自引:0,他引:3
Hossam I. Abdalla Consultant Anne Billett Clinical Research Fellow rew K. S. Kan Clinical Research Fellow Sabah Baig Clinical Research Fellow Marie Wren Infertility Specialist Lena Korea Ovum Donation Co-ordinator John W. W. Studd Consultant 《BJOG : an international journal of obstetrics and gynaecology》1998,105(3):332-337
89.
上海市某区居民脑卒中死亡与大气污染关系的时间序列研究 总被引:4,自引:0,他引:4
目的 分析大气污染急性暴露对居民每日脑卒中死亡的影响。方法 采用时间序列的半参数广义相加模型 ,在控制死亡的长期趋势、气象因素、“星期几效应”等混杂因素的基础上 ,分析了上海市某区 2 0 0 1年 1月 1日~ 12月 31日大气污染与居民每日脑卒中死亡的关系。结果 大气PM10 ,SO2 和NO2 4 8h平均浓度每增加 10 μg m3 ,居民因脑卒中而死亡的相对危险度分别为 1 0 0 8(95 %CI 1 0 0 0~ 1 0 16 ) ,1 0 17(95 %CI 0 998~ 1 0 36 )和 1 0 2 9(95 %CI1 0 0 1~ 1 0 5 7)。结论 上海市某区目前的PM10 和NO2 水平对居民脑卒中死亡有影响。 相似文献
90.
应用改进的眼震图检查先天性眼球震颤 总被引:2,自引:0,他引:2
目的评价改进后的眼震图对先天性眼球震颤波形的分析,为其手术治疗提供较为精确的量化标准.方法改进电生理仪的视网膜电图(EOG)程序,分别记录68例患者33cm原在位、右5°、10°、15°、20°,左5°、10°、15°、20°,3m原在位及闭眼的波形,并对其中28例手术患者术前和术后的眼震图进行比较.结果68例患者中,跳动型48例,其中水平跳动46例,垂直跳动2例;水平钟摆型20例.跳动型中,有代偿头位的40例,钟摆型无明显代偿头位.28例手术患者中,水平跳动型26例,水平钟摆型2例.26例跳动型患者均有中间位和代偿头位.术后20例代偿头位消失,6例代偿头位在左5°~10°.按震频、振幅、震强的分组中,处于中等震频、振幅、震强范围内的多见.结论改进的眼震图可以对眼震的振幅、震频、震强、中间位进行量化的检测,从而指导其治疗. 相似文献