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排序方式: 共有10000条查询结果,搜索用时 312 毫秒
991.
目的:对使用荧光分光光度法测定水产品中烷烃类、芳烃类污染物的方法进行验证,并检测三类样品。方法:通过氢氧化钠-乙醇皂化处理,用正已烷萃取,用石油醚溶解,测量萃取物荧光强度值进行定量。结果:测得标准油在0.00~12.0μg/ml范围内线性关系良好,相关系数0.9999,检出限为0.2 mg/kg,平均回收率90.2%,RSD5.4%。结论:本法准确度、灵敏度高,检出限低,操作稳定性好。 相似文献
992.
C De Simone A Misefari V Covelli A B Maffione S Antonaci E Jirillo 《Journal of clinical laboratory analysis》1989,3(6):345-349
The effects of substance P (SP) on Salmonella minnesota R345 (Rb) binding to human peripheral blood lymphocytes (PBL) were evaluated. Two parameters of bacterial cytoadherence were considered, namely the binding lymphocytes (BL) and the number of bound-bacteria/lymphocyte (BB). The results showed that SP inhibits both BL and BB in a significant manner. Furthermore, distribution of Salmonella binding to CD4+ and CD8+ lymphocytes was studied following SP pretreatment of lymphoid cells. This neuropeptide is able to hamper the bacterial cytoadherence to both T-cell subpopulations and, in particular, the inhibitory effect on the T-suppressor/cytotoxic subset was more pronounced. These findings are discussed in terms of SP intervention in the mechanism of host protection against invading microorganisms. 相似文献
993.
Jerome B. Simon 《Cancer metastasis reviews》1987,6(3):397-411
Testing feces for occult blood is widely recommended as a means of detecting subclinical colorectal tumors. Guaiac tests such as Hemoccult® are the most widely used, but chemical sensitivity is relatively low and the tests are affected by dietary peroxidases, the state of fecal hydration, and certain drugs. The newly devised HemoQuant® and immunologic techniques appear more sensitive and specific, but they require further evaluation before widespread clinical usage can be recommended.Occult blood screening has both merits and weaknesses. Testing does uncover subclinical colorectal cancer, often at a relatively early stage, but whether this actually improves the prognosis remains to be proven. Benign neoplastic polyps are also detected, although it is debatable whether this is a valid rationale for screening. Test sensitivity for malignancy varies from good to moderate, but is poor for benign polyps. Specificity is usually around 97%–98%, yet the predictive value of a positive test for cancer is only about 10%: hence most test-positive individuals are needlessly subjected to invasive colonic investigations. Reported figures on public compliance with occult blood testing vary widely from excellent to poor. Published costs of screening are usually quite low, but these overlook important indirect and hidden expenses and are therefore misleading.On balance, the problems of occult blood testing currently appear to outweight the merits. This could change, however, with the newer testing techniques and with awaited mortality data from controlled clinical trials now underway. 相似文献
994.
Koji Tomobe Hajime Fujii Buxiang Sun Hiroshi Nishioka Okezie I Aruoma 《Biomedicine & Pharmacotherapy》2007,61(7):427-434
Oligonol is produced from the oligomerization of polyphenols (typically proanthocyanidin from a variety of fruits such as lychees, grapes, apples, persimmons, etc.) and contains catechin-type monomers and oligomers of proanthocyanidins. The ability of Oligonol to affect infection-dependent eye inflammation, locomotion and longevity in senescence-accelerated prone mice (SAMP8) (a model of senescence acceleration and geriatric disorders with increased oxidative stress and neuronal deficit) was investigated. Oligonol (60mg/kg) significantly modulated the extent of inflammation scores in the eye of SAMP8 mice. Examination of the mice indicated infection with mouse hepatitis virus and pinworm (Syphacia obvelata) in both males and females and with the intestinal protozoa (trichomonad) in males. A comparison of the two groups (using log-rank test) and the difference in the mean life span between groups (using Student's t-test) indicated significant differences in survival (p=0.043) and the mean life span (p=0.033) in male SAMP8 mice. Oligonol increased the mean life span and this was statistically significant. In the open-field locomotive test, the 7-week-old SAMP8 mice crossed more than 40 partitioned lines in 1min. At 48-week-old control untreated male SAMP8 crossed 2 lines. The Oligonol-treated 48-week-old male SAMP8 mice crossed 17 lines however. The improved locomotive activity was statistically significant even after 36weeks in the Oligonol-treated male SAMP8 but this was not the case throughout the time course of the study in the Oligonol-treated female SAMP8. Thus Oligonol treatment to SAMP8 mice modulated the severity of infection-dependent inflammation, prolonged life-span and significantly improved locomotive activity indicating potential benefit to aging-associated diseases such as Alzheimer's or Parkinson's diseases. This presents potential for further research to define infection-dependent inflammation associated with degenerative conditions and the molecular mechanism of dietary antioxidant protection. 相似文献
995.
肖远辉 《天津中医药大学学报》2002,21(1):20-20
笔者于1998年2月~1999年12月应用温针灸为主治疗前列腺增生症51例,效果理想.现报道如下. 1临床资料 1.1病例选择全部98例观察病例均来自男科门诊.按随机法分为治疗组和对照组.其中治疗组51例,年龄最小49岁,最大72岁,平均56.3岁;病程最短2年,最长5年,平均4.1年.对照组47例,年龄最小48岁,最大71岁,平均57.1岁;病程最短3年,最长7年,平均5.0年.两组具有可比性. 相似文献
996.
不同病因腹泻病儿肠道主要菌群变化的研究和比较 总被引:1,自引:0,他引:1
对88例不同病因腹泻儿肠道双歧杆菌、乳酸杆菌、大肠杆菌的变化进行研究。对照组25例。结果:研究组较对照组双歧杆菌、乳酸杆菌有显著下降(P<0.01和P<0.05),大肠杆菌下降不明显(P<0.05)。非感染性腹泻组较感染性腹泻组双歧杆菌、乳酸杆菌下降更显著(P<0.01和P<0.05),大肠杆菌下降不显著(P<0.05)。感染性腹泻组中,双歧杆菌在轮状病毒肠炎组中较急性菌痢下降更显著(P<0.05),而其它两种菌下降程度相差不明显(两者P<0.05) 相似文献
997.
白术茯苓汤及其配伍对脾虚大鼠胃肠激素的影响 总被引:3,自引:0,他引:3
目的:探讨益气健脾方剂治疗脾虚证的配伍规律。方法:采用苦寒泻下法复制大鼠脾虚模型,运用放射免疫分析法(RIA)检测白术茯苓汤及其与补气药。行气药及除湿药的不同配伍对脾虚大鼠胃泌素(GAS)、胃动素(MTL)及血管活性肠肽(VIP)的含量影响。结果:与正常对照组比较,脾虚模型大鼠GAS、MTL降低(P<0.01),VIP升高(P<0.01);与自然恢复组比较,各治疗组以上部分或全部指标均有不同程度的改善,其中,以综合配伍组改善作用最优。结论:白术茯苓汤的脾虚大鼠胃肠激素的紊乱的某些指标,有一定的改善作用,综合配合组以上指标的改善,优于白术茯苓汤组及其余各配伍组,说明中医关于复方配伍的理论与实践,有其科学价值。 相似文献
998.
目的探讨血压正常老年患者和老年高血压患者24h动态血压波动规律及与靶器官损害的关系.方法采用无创伤袖带式动态血压监测仪检测36例中年人(对照组),50例血压正常老年患者,60例老年高血压患者的动态血压.结果血压正常老年患者较中年血压正常者24h动态血压呈杓型曲线的比例明显下降.血压正常老年患者,血压昼夜波动曲线与心、脑、肾损害无相关性.老年高血压患者,血压曲线呈非杓型者比例增高,血压昼夜节律消失较节律正常的高血压患者有更显著的靶器官损害.结论对于非高血压患者,随年龄的增加,血压昼夜节律消失者增多,血压曲线变化与心、脑、肾损害无关,可能与原发病有关.对于高血压患者,血压昼夜节律紊乱可作为靶器官损害的预测因子. 相似文献
999.
目的 探讨黄芪注射液对心力衰竭 (HF)的治疗效果。方法 选择 92例住院HF患者随机分为治疗组和对照组 ,对照组给予常规治疗 ,治疗组在常规治疗的基础上给予黄芪注射液 30ml加 5 %葡萄糖液 2 5 0ml,静滴 ,每日一次 ,共 2周。疗程结束后 ,观察心功能改善情况。结果 治疗组有效率 93.4 8% ,对照组有效率 71.74 % ,两组对比 ,差异显著 (P <0 .0 1)。结论 黄芪注射液对HF的治疗效果佳 ,副作用少 ,值得推广。 相似文献
1000.
养阴清热、宣痹通络法治疗类风湿性关节炎的临床研究 总被引:5,自引:0,他引:5
目的 观察清络通痹颗粒治疗类风湿性关节炎阴虚络热证的临床疗效。方法 将118例患者随机分为清络通痹颗粒治疗组63例和雷公藤多甙片对照组55例,观察用药前后主要症状、体征和实验室检测指标的变化。结果 治疗组的临床治愈率为9.52%,临床治愈显效率为38.10%,总有效率为90.48%,疗效明显优于对照组的0%、20%、83.64%(P<0.05);治疗组的类风湿因子滴度、血沉、C反应蛋白、免疫球蛋白也明显降低,与对照组相比差异显著(P<0.05或P<0.01)。结论 清络通痹颗粒具有抗炎镇痛、调节免疫紊乱等作用,从而达到控制病情的治疗效果。 相似文献