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排序方式: 共有3248条查询结果,搜索用时 15 毫秒
951.
952.
Emilio González-Reimers Elena García-Valdecasas-Campelo Francisco Santolaria-Fernández María José de la Vega-Prieto Rosa Ros-Vilamajó Antonio Martínez-Riera Ana Castellano-Higuera Melchor Rodríguez-Gaspar 《Food and chemical toxicology》2007,45(6):904-909
Cytokines are mediators of the inflammatory response, secreted by many tissues, including adipocytes. Chronic alcoholic liver disease and alcoholic hepatitis are associated with elevated serum cytokine levels which yield prognostic value in this situation. Most studies have been performed in patients with acute alcoholic hepatitis. However, cytokine alterations in stable alcoholics have been less studied, as is also the case for the relationship between cytokines and fat and lean mass in these patients. The aim of the present study was to analyse the relationships between some proinflammatory serum cytokine levels and lean mass, fat mass, nutritional status, and liver function parameters in stable alcoholic patients. We determined serum TNF-alpha, interleukin (IL)-6, IL-8 and TNF receptor 2 (TNFr2) in 77 male alcoholic patients in a stable phase (before hospital discharge). In all patients we performed a total-body composition analysis (Hologic DEXA), nutritional assessment including body mass index, triceps skinfold, brachial perimeter, and assessment of liver function. Forty-two healthy volunteer health workers served as controls. IL-8, TNF-alpha and TNFr2 were significantly higher in patients than in controls. No differences were observed between patients and controls regarding fat mass, but alcoholics showed significantly decreased lean mass than controls. Only IL-6 was significantly related with body fat in patients with elevated IL-6 levels. Poor relationships were observed between lean mass and cytokines; some nutritional parameters showed inverse relationships with serum TNF, whereas TNF and IL-8 were inversely related with albumin and prothrombin activity. Thus, cytokine levels were elevated in stable alcoholic patients, and IL-6 levels showed significant correlation with body fat mass, raising the possibility that adipose tissue contributes to the persistence of high levels of cytokines in stable alcoholics. 相似文献
953.
本文以2006年10月在FDA获得批准的处方药VeregenTM的商品说明书为切入点,详细分析了作为植物药的VeregenTM在FDA审批过程中的一些关键点。中药走向世界是个漫长而艰苦的过程,但VeregenTM的例子证明,中药作为植物药在FDA注册成功不是不可能的。本文的分析与建议希望能为中药敲开FDA大门提供些许有价值的参考,给准备走向国际市场的国内中药制药企业一些有益的指导。 相似文献
954.
广州市售糕点、熟肉制品中人工合成色素含量的现状分析 总被引:4,自引:0,他引:4
目的:为全面了解广州市售糕点、熟肉制品中人工合成色素含量情况。方法:对市场上销售的糕点、熟肉制品进行随机抽样调查,用高效液相色谱法检测分析了72份糕点、91份烧卤熟肉制品中人工合成色素柠檬黄、苋菜红、胭脂红、日落黄、亮蓝的含量。结果:发现检出样品中,糕点中人工合成色素的不合格率为36.11%,熟肉制品中人工合成色素的不合格率为6.59%,以上结果说明,糕点、熟肉制品中滥用人工合成色素情况比较严重,特别是糕点行业,合格率仅为60.66%,应引起有关部门的高度重视。结论:为了进一步提高市民食用糕点、烧卤熟肉制品的安全性及减少对人体健康的危害,建议加强消费市场的卫生监督。 相似文献
955.
新型农村合作医疗中政府责任定位的若干思考 总被引:1,自引:0,他引:1
从公共产品的角度,分析了目前新型农村合作医疗制度中存在的政府管理问题,探讨了政府在这一制度中承担责任的必然性,并对政府在该制度中的责任定位进行阐述,旨在促进该制度的健康发展。 相似文献
956.
目的 动态监测使用不同钙浓度腹膜透析液行持续性不卧床腹膜透析(CAPD)对尿毒症患者钙磷代谢的影响。方法将加例初行CAPD的尿毒症患者随机分为标准钙组和低钙组,每组各20例,行正规CAPD治疗并配合碳酸钙口服,观察12个月。结果两组患者初行CAPD时,血清钙、磷、钙磷乘积及免疫反应性甲状旁腺素(iPTH)浓度比较差异均无统计学意义,普遍存在高磷血症及低iPTH血症。经过6个月的治疗,标准钙组患者的高钙、高磷血症进一步加重,而低钙组患者的血清钙[(2.29±0.27)mmol/L]、血清磷[(1.50±0.25)mmol/L]及钙磷乘积[(41.62±19.55)mg^2/dl^2]较治疗前显著降低,且均低于治疗后的同期标准钙组患者(P〈0.01),iPTH则显著上升(P〈0.01)。在随后的6个月中,低钙组患者血清钙、钙磷乘积保持稳定并维持在正常范围,血清磷进一步降至正常范围(0.8~1.5mmol/L),iPTH则维持在150ng/L左右,与标准钙组比较有显著改善(P〈0.01)。结论低钙浓度腹膜透析液有助于减轻尿毒症CAPD患者的钙磷代谢紊乱,延缓并发症的发生。 相似文献
957.
Michael S. Werley Susan A. Freelin Susan E. Wrenn Birgit Gerstenberg Ewald Roemer Heike Schramke Erik Van Miert Patrick Vanscheeuwijck Susanne Weber Christopher R.E. Coggins 《Regulatory toxicology and pharmacology : RTP》2008
The Electrically Heated Cigarette Smoking System Series K (EHCSS) produces smoke through the controlled electrical heating of tobacco. Evaluation of the EHCSS was accomplished by comparison with commercial and reference cigarettes, using International Organization for Standardization (ISO) and alternative puffing regimens based on nicotine exposures measured in a short-term clinical study. Using the alternative puffing regimen and compared with conventional cigarettes on a per cigarette basis, the EHCSS had 50–60% reductions in tar and nicotine; at least 90% reductions in carbon monoxide, nitrogen oxides, 1,3-butadiene, isoprene, acrylonitrile, polyaromatic hydrocarbons, hydrogen cyanide, aromatic amines, tobacco specific nitrosamines, and phenol; and least a 40% reduction in 2-nitropropane. Other important smoke constituents in EHCSS smoke were reduced as well. The in vitro studies showed similar large reductions in biological activity. Ames mutagenicity of total particulate matter (TPM) from the EHCSS was reduced by 70–90%; cytotoxicity of the TPM was reduced by approximately 82% and 65% for the gas–vapor phase. In vivo testing under ISO smoking conditions in the mouse skin painting assay demonstrated later dermal tumor onset, lower dermal tumor incidence, reduced dermal tumor multiplicity, and a lower proportion of malignant dermal tumors in EHCSS smoke condensate-exposed mice. Thirty-five day and 90-day nose-only inhalation studies in rats showed reductions in pulmonary inflammation and other biological activity, including histopathological endpoints. We conclude that under the conditions of these in vitro and in vivo studies, the EHCSS demonstrated significantly lower biological activity compared to conventional cigarettes, and may suggest the potential for reductions in human smokers. 相似文献
958.
959.
植物内生真菌HCCB 01546中的抗肿瘤活性物质 总被引:4,自引:0,他引:4
用抗肿瘤体外细胞毒筛选模型研究内生真菌HCCB01546发酵产物中的活性成分,经溶剂萃取、硅胶柱、ODS柱色谱及制备HPLC等分离手段得到两个活性物质,通过理化性质及波谱分析,分别确定为epoxycytochalasin H及cytochalasin N。活性测试结果发现前者有较明显的抗肿瘤活性。 相似文献
960.
广东省水产品中香港海鸥型菌的污染调查与耐药性检测 总被引:1,自引:0,他引:1
目的 初步了解广东省水产品中香港海鸥型菌(Laribacter hongkongensis)污染及分离株的耐药情况.方法 采用改良头孢哌酮麦康凯琼脂(CMA)作为分离培养基,以API 20NE鉴定系统鉴定结果作为确认依据;采用K-B法进行药物敏感试验.结果 222份水产样本检出15株目标菌,阳性率6.76%.其中14株分离自草鱼肠脏,1株来自鲤鱼肠脏.分离株及香港海鸥型菌模式株HKU1的药敏结果,对β-内酰胺类抗生素如氨苄西林、头孢噻酚、头孢他啶、头孢曲松等均出现耐药株,未见耐庆大霉素和阿米卡星株.结论 结果表明香港海鸥型菌在广东省的草鱼污染率最高,为17.3%(14/81),分离株对β-内酰胺类抗生素耐药情况较严重. 相似文献