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91.
This study aimed to evaluate the efficacy of chitosan-silver nanocomposites in the treatment of experimentally infested pigeons with Pseudolynchia canariensis (P. canariensis) with evaluation of different immunological parameters before and after treatment. Therefore, fourteen birds were divided into 2 groups; group1(infested group including 12 birds) which subdivided into 6 sub-groups experimentally infested pigeons 2 pigeons each, and five group of them were treated with chitosan-silver nanocomposites and sub-group number 6 was treated with deltamethrin while, group 2 including two pigeons were kept as control negative ones. P. canariensis flies distributed under the wing and /or under the tail in infested group and these pigeons showed significantly lower RBCs and higher WBCs than that in non-infested pigeons. The cell mediated immune response against experimentally infested pigeons with P. canariensis was studied. P. canariensis infestation in pigeons have a negative impact on pigeon’s blood parameters, increase TNF-α and IL-1β cytokines levels. This study cleared out the role of P. canariensis in the induction of a case of oxidative stress indicated by high level of nitric oxide and malondialdehyde (MDA) with low antioxidant capacity in shape of reduced zinc concentration in the sera of experimentally infested pigeon. Chitosan-silver nanocomposite has a promising effect in the elimination of P. canariensis infestation in pigeons.  相似文献   
92.
研究植物源性发酵乳杆菌对免疫系统生理活性、抗高血糖和促进肠蠕动的影响.β-内啡肽对免疫系统有重要作用,阿片-促黑素细胞皮质素原(POMC)是β-内啡肽的前体物质,为了探讨发酵乳杆菌对免疫功能的影响,检测小鼠下丘脑和脑垂体中POMC的基因表达水平.通过喂食发酵乳杆菌时间和浓度的不同及测量β一内啡肽表达水平的方式,来分析血液中B-内啡肽的变化情况.此外,测定了三种小鼠模型的血糖变化,即常规的WT小鼠模型、D-葡萄糖诱导的急性高血糖模型和链唑霉素(STZ)诱导的糖尿病模型,以证实发酵乳杆菌的降血糖效果,并对降血糖效果进行了验证.通过检测血糖随喂食发酵乳杆菌浓度和时间而变化的情况,已证实给药浓度和时间对血糖浓度有很好的影响.另外,为证实发酵乳杆菌对肠蠕动的影响测定了胃肠通过时间,证明发酵乳杆菌对肠蠕动有极好的促进作用.通过此项研究,证实发酵乳杆菌对提高人体免疫系统的生理活性、抗高血糖和促进小肠蠕动有极佳的效果.  相似文献   
93.
目的:探讨肝切除手术运用Pringle法阻断、半肝血流阻断(HVC)后对原发性肝癌合并肝硬化患者肝功能及肠黏膜屏障的影响。方法:选取2016年4月~2019年9月期间我院收治的原发性肝癌合并肝硬化患者93例,根据随机数字表法将患者分为A组(n=46,Pringle法阻断)和B组(n=47,HVC),比较两组患者围术期指标、肝功能指标[谷丙转氨酶(ALT)、谷草转氨酶(AST)以及总胆红素(TBIL)]、肠黏膜屏障指标[D-乳酸,内毒素]及并发症发生情况。结果:两组阻断时间、术中失血量、手术时间比较无差异(P0.05);B组住院时间短于A组(P0.05)。两组术前、术后3 d、术后7 d ALT、AST、TBIL呈升高后降低趋势,且B组低于A组(P0.05)。两组患者术后并发症发生率比较无差异(P0.05)。两组术前、术后3 d、术后7dD-乳酸、内毒素呈升高后降低趋势,且B组低于A组(P0.05)。结论:与Pringle法阻断相比,原发性肝癌合并肝硬化患者在肝切除手术中运用HVC,可有效缩短住院时间,减轻肝功能及肠黏膜屏障损害,且不增加并发症发生率,临床应用价值较高。  相似文献   
94.
We compare blood pressure and hypertension between adult men on the USA mainland and in Puerto Rico born during 1886-1930 to test hypotheses about the link between cardiovascular health and large socioeconomic and political changes in society: (a) 8853 men surveyed in Puerto Rico in 1965 and (b) 1449 non-Hispanic White men surveyed on the mainland during 1971-1975. Systolic and diastolic blood pressure and hypertension were regressed separately on demographic and socioeconomic variables and cardiovascular risk factors. Mainland men not taking anti-hypertensive medication showed statistically significant improvements in systolic blood pressure and hypertension at the beginning of the century and men in Puerto Rico showed improvements in diastolic blood pressure but only during the last two quinquenniums. An average man born on the mainland during the last birth quinquennium (1926-1930) had 7.4-8.7 mmHg lower systolic blood pressure and was 61% less likely to have systolic hypertension than one born before 1901. On average Puerto Rican men born during 1921-1925 had approximately 1.7 mmHg lower diastolic blood pressure than men born before 1901. Analyses of secular trends in cardiovascular health complements analyses of secular trends in anthropometric indicators and together provide a fuller view of the changing health status of a population.  相似文献   
95.
目的了解本院儿童血培养凝固酶阴性葡萄球菌(CNS)的感染率及其药物敏感情况,为儿科合理使用抗生素提供依据。方法对本院2006年1月至2007年12月间住院及门诊儿童血液培养的结果进行回顾性统计分析。结果在1265例儿童血培养中共检出CNS117株,其中表皮葡萄球菌41株(占35.0%),人葡萄球菌27株(占23.1%),溶血葡萄球菌21株(占18.0%),其他凝固酶阴性葡萄球菌28株(占23.9%);耐甲氧西林凝固酶阴性葡萄球菌(MRCNS)分离率为79.5%;MRCNS药敏结果显示多重耐药。结论CNS已成为儿童血液感染的重要致病菌,MRCNS检出率高且多重耐药,万古霉素、喹宁始霉素-达福普汀、呋西地酸是治疗MRCNS感染的首选药物。  相似文献   
96.
目的了解临床各科发热患者(怀疑细菌感染)血培养中葡萄球菌分布及耐药性,为临床治疗提供参考依据。方法血培养采用BaeT/Alert3D全自动血培养仪(梅里埃)培养5d,采用MicroScanWalk—Away-96plus全自动微生物鉴定和药敏分析系统(西门子)进行细菌鉴定和药敏试验。结果血培养共检出葡萄球菌185株,检出最多的科室是ICU,耐甲氧西林金黄色葡萄球菌(methicillin—resistant Staphylococcus aureus,MRSA)检出率为30.4%,而耐甲氧西林凝固酶阴性葡萄球菌(methicillin—resistant coagulase-negative Staphylococci,MRCNS)的检出率高达80.7%。还检出了1株万古霉素中介的凝固酶阴性葡萄球菌。结论通过血培养检出葡萄球菌的耐药性分析发现,凝固酶阴性葡萄球菌对苯唑西林、氨苄西林、青霉素、红霉素的耐药率在70%以上,而对氯霉素、利福平、四环素的耐药率在30%以下,因此这三种药物应为我院应对凝固酶阴性葡萄球菌血流感染的常用首选药物。  相似文献   
97.
Transmissible spongiform encephalopathies (TSEs), otherwise known as prion disorders, are fatal diseases causing neurodegeneration in a wide range of mammalian hosts, including humans. The causative agents - prions - are thought to be composed of a rogue isoform of the endogenous prion protein (PrP). Beyond these and other basic concepts, fundamental questions in prion biology remain unanswered, such as the physiological function of PrP, the molecular mechanisms underlying prion pathogenesis, and the origin of prions. To date, the occurrence of TSEs in lower vertebrates like fish and birds has received only limited attention, despite the fact that these animals possess bona fide PrPs. Recent findings, however, have brought fish before the footlights of prion research. Fish models are beginning to provide useful insights into the roles of PrP in health and disease, as well as the potential risk of prion transmission between fish and mammals. Although still in its infancy, the use of fish models in TSE research could significantly improve our basic understanding of prion diseases, and also help anticipate risks to public health. This article is part of a Special Issue entitled Zebrafish Models of Neurological Diseases.  相似文献   
98.
脑部靶向给药技术   总被引:1,自引:0,他引:1  
介于脑部毛细血管与脑组织之间的血脑屏障是一层难以通过的生理屏障 ,能够阻挡大多数外源物质进入脑内。临床上采用的中枢神经系统药物大多是能够扩散通过血脑屏障的小分子脂溶性物质 ,而这类药物已经远远不能满足临床需要 ,很多疾病的诊断、治疗需要大分子、水溶性物质。传统的将这类大分子药物导入脑部的方法效果差、危险性大 ,因此近年来针对能够通过血脑屏障脑部靶向给药技术的研究逐渐成为热点。综述了近年来国际上使用嵌合肽、免疫脂质体及纳米粒子解决脑部靶向性给药的研究进展。  相似文献   
99.
A butter-enriched high-fat diet changes lipid metabolism, resulting in fat storage, hyperlipidemia and obesity. Effects of cinnamon powder were investigated in butter-fed mice. 40 Swiss Albino mice, aged 28 to 30 days, were randomly assigned into two groups. Group A was an untreated control group (n = 8) and another group (n = 32) was a butter-treated group fed 10% butter. In the fifth week, mice of the butter-fed group were further divided into four equal groups: B, C, D, and E (n = 8), fed 10% butter with cinnamon 200 mg, 400 mg, and 600 mg powder per liter drinking water, respectively for 10 weeks. The butter-fed group was gained the most weight. Cinnamon supplementation significantly normalized weight gain and had no harmful effects on hematological parameters. Butter supplementation significantly increased total cholesterol (TC), triglycerides, and LDL cholesterol (LDL-c) whereas, cinnamon powder significantly reduced TC, LDL-c and glucose levels. In butter-fed mice, a significant increase was observed in the liver enzymes, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels with subsequent fat deposition in the liver. Excitingly, these enzymes were decreased and no fat depositions were observed in the liver of cinnamon-treated mice. Applying different concentrations of cinnamon powder improved the lipid profile in butter-fed female albino mice.  相似文献   
100.
目的 探讨木犀草素通过调节凝血活性物质及凝血因子含量维持机体血液循环功能的作用机制。 方法 采用试剂盒和试管法测定木犀草素作用后的凝血酶原时间和血浆复钙时间;采用酶联免疫吸附法检测木犀草素对血液凝血活性物质血栓素(TXB2)、纤维酶原激活物抑制剂(PAI 1)、促红细胞生成素(EPO)和凝血因子Ⅶ(FⅦ)、凝血因子Ⅸ(FⅨ)含量的影响;采用PCR法测定木犀草素对凝血因子Ⅶ、Ⅸ的基因表达情况。 结果 木犀草素能缩短凝血酶原时间和血浆复钙时间,与对照组相比,40 mg/kg的木犀草素使凝血酶原时间和血浆复钙时间分别降低62.89%和64.05%(t=8.713 6、6.218 1,均P结论 木犀草素具有维持机体血液循环功能稳定的作用,其作用机制是通过提高凝血活性物质的含量,调节凝血因子的基因表达量,提高凝血因子的含量,以及抑制纤维酶原的激活和增加血液的黏度等多方面综合作用来实现的。  相似文献   
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