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61.
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
62.
63.
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
64.
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
65.
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
66.
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
67.
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
68.
Sascha Fauser Hubert Kalbacher Nils Alteheld Kan Koizumi Tim U. Krohne Antonia M. Joussen 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2004,242(7):582-586
Background The anti-inflammatory drug etanercept may be an effective therapeutic agent in diabetic retinopathy. In order to further evaluate its potential, the pharmacokinetics and safety of this drug after intravitreal delivery were investigated.Methods After intravitreal administration of etanercept in rabbits, clinical examination, electroretinography (ERG), visually evoked potentials (VEP) and histology were evaluated. The pharmacokinetics and distribution of etanercept were analyzed using fluorescence-coupled protein at 0, 2, 4, and 8 weeks after injection in vitreous, retina, and choroid.Results No adverse effects and signs of toxicity were found. Etanercept showed peak concentrations after 4 weeks in the retina and choroid.Conclusions Intravitreally delivered etanercept is safe and results in high concentrations in the retina and choroid over a long period of time. 相似文献
69.
医院信息系统(HIS)是医院管理不可分割的部分,其数据安全性、可靠性至关重要,然而,从医院现状来看,网络设施、网络环境、网络安全等方面,还存在诸多漏洞,制定科学周密、安全可靠的应对措施,是医院信息管理的当务之急。 相似文献
70.
目的:通过哈萨克族与汉族女性胰岛素抵抗相关因素与血压关系的对比,分析是否存在种族差异。方法:抽取哈、汉民族女性共122人,哈、汉民族皆分为健康人群组及高血压人群组,比较各民族相应人群的胰岛素抵抗相关因素,采用直线相关分析分析各民族之间胰岛素抵抗相关因素与血压之间的关系。结果:在高血压人群组,哈族女性胰岛素抵抗指数(5.3±2.0)显著高于汉族女性(4.3±1.9);在健康人群组,哈族女性胰岛素抵抗指数(4.6±1.3)显著高于汉族女性(3.5±1.2);汉族女性胰岛素抵抗指数与血压显著正相关(r=0.273,P=0.034),瘦素水平与血压显著正相关(r=0.310,P=0.015);哈族女性瘦素水平及胰岛素抵抗指数与血压不相关。结论:哈族女性胰岛素抵抗显著高于汉族女性,存在种族差异;汉族女性胰岛素抵抗指数及瘦素水平与血压显著正相关,而哈族女性胰岛素抵抗指数及瘦素水平与血压不相关,存在种族差异。 相似文献