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41.
Secondary to surgery, patients are subjected to metabolic changes and physiological immunosuppression that increase the risk of infection and other postoperative complications. Several ways, included pharmaco-nutrition, could attenuate surgical stress and reduce postoperative morbidity. The postoperative administration of a diet, containing three immuno-nutrients (arginine, nucleotides and fish oil) (Impact®), reduces postoperative morbidity in all types of serious gastrointestinal surgeries. The effect is greater when the product is given pre-and postoperatively. It is noticeable that the effect of immune-nutrition in patients undergoing ERAS techniques has not been investigated. Several studies showed that intravenous form of glutamine (Dipeptiven®) reduces infectious complications and postoperative hospital length of stay. In patient with major postoperative complication receiving parenteral nutrition, glutamine administration is recommended. There is more uncertainty about the clinical effects of intravenous fish oils (EPA and DHA). Most of studies, conducted in small series of patients, showed a tendency to decrease infectious complications and length of stay. Therefore, in patients on parenteral nutrition and with a high-risk of postoperative complications, it is probably indicated to use lipid emulsions containing fish oil. A minimum length of administration is required (at least five days) to expect to have beneficial effects. The use of pharmaco-nutrients must be integrated into an overall management of perioperative patient whose objective is to reduce the postoperative aggression.  相似文献   
42.
Nitric oxide is well known for its roles in immune responses. As such, its synthesizing enzymes have been extensively studied from various species including some teleost fish species. However, the NOS genes have not been characterized in channel catfish (Ictalurus punctatus). In this study, we identified and characterized three NOS genes including one NOS1 and two NOS2 genes in channel catfish. Comparing with the NOS genes from other fish species, the catfish NOS genes are highly conserved in their structural features. Phylogenetic and syntenic analyses allowed determination of NOS1 and NOS2 genes of channel catfish and their orthology relationships. Syntenic analysis, as well as the phylogenetic analysis, indicated that the two NOS2 genes of catfish were lineage-specific duplication. The NOS genes were broadly expressed in most tested tissues, with NOS1 being expressed at the highest levels in the brain, NOS2b1 highly expressed in the skin and gill, and NOS2b2 lowly expressed in most of the tested tissues. The most striking findings of this study was that the expression of the NOS genes are highly regulated after bacterial infection, with time-dependent expression patterns that parallel the migration of macrophages. After Edwardsiella ictaluri challenge, dramatically different responses among the three NOS genes were observed. NOS1 was only significantly in the skin early after infection, while NOS2b1 was rapidly upregulated in gill, but more up-regulated in trunk kidney with the progression of the disease, suggesting such differences in gene expression may be reflective of the migration of macrophages among various tissues of the infected fish. In contrast to NOS1 and NOS2b1, NOS2b2 was normally expressed at very low levels, but it is induced in the brain and liver while significantly down-regulated in most other tissues.  相似文献   
43.
This discussion is on immune response to Amyloodinium ocellatum, Cryptobia salmositica, Trypanoplasma borreli and Trypanosoma carassii. Piscidin and histone-like proteins enhance innate resistance to Amyloodinium. Fish that are naturally resistant to Cryptobia and Trypanoplasma can be bred. Cryptobia resistance in charr is controlled by a dominant Mendelian locus and protection is via the Alternative Pathway of Complement Activation. Studies on Cryptobia-tolerant charr may lead to production of transgenic Cryptobia-tolerant salmon. Innate response to T. borreli is associated with NO in macrophages. Transferrin regulates resistance and carp have been bred for transferrin genotypes. Recovered fish are protected from homologous challenge, and complement fixing antibodies are crucial in protection. Studies on antigens in T. carassii may lead to a vaccine. There are two vaccines against cryptobiosis; a single dose of the attenuated vaccine protects salmonids. On challenge fish inoculated with the metalloprotease-DNA vaccine do not have the disease and they recover faster.  相似文献   
44.
A kindred affected with fish eye disease (FED) from Oklahoma is reported. Two probands with corneal opacification had mean levels of high-density lipoprotein (HDL) cholesterol (C), apolipoprotein (apo) A-I, and apoA-I in very large alpha-1 HDL particles that were 9%, 17%, and 5% of normal, whereas their parents and 1 sibling had values that were 61%, 77%, and 72% of normal. The probands had no detectable lipoprotein-X, and had mean low-density lipoprotein cholesterol (LDL-C) and triglyceride levels that were elevated. Their mean lecithin cholesterol acyltransferase (LCAT) activities, cholesterol esterification rates, and free cholesterol levels were 8%, 42%, and 258% of normal, whereas their parents and 1 sibling had values that were 55%, 49%, and 114% of normal. The defect was due to 1 common variant in the LCAT gene in exon 1: c101t causing a proline34leucine substitution and a novel mutation c1177t causing a threonine37methionine substitution, with the former variant being found in the father and 1 sibling, and the latter mutation being found in the mother, and both mutations being present in the 2 probands. FED is distinguished from familial LCAT deficiency (FLD) by the lack of anemia, splenomegaly, and renal insufficiency as well as normal or increased LDL-C. Both FLD and FED cases have marked HDL deficiency and corneal opacification, and FED cases may have premature coronary heart disease in contrast to FLD cases. Therapy, using presently available agents, in FED should be to optimize LDL-C levels, and 1 proband responded well to statin therapy. The investigational use of human recombinant LCAT as an enzyme source is ongoing.  相似文献   
45.
目的:研究膜荚黄芪叶中的三萜皂苷类成分。方法:采用硅胶、十八烷基硅烷键合硅胶(ODS)等色谱方法对膜荚黄芪叶的化学成分进行分离,通过一维核磁共振氢谱(1D-NMR)和2D-NMR法分析鉴定化合物。结果:从膜荚黄芪叶提取物中共分离出15个化合物,分别鉴定为黄芪叶苷B(1)、黄芪叶苷L(2)、cyclounifolioside D(3)、3-O-[α-L-吡喃鼠李糖基-(1→2)-β-D-吡喃木糖基]-6-O-β-D-吡喃葡萄糖基-24-O-α-L-吡喃阿拉伯糖基-16-乙酰基-3β,6α,16β,24(S),25-五羟基环菠萝蜜烷(4)、黄芪叶苷K(5)、黄芪叶苷A(6)、astraverrucinⅠ(7)、cycloaraloside A(8)、黄芪叶苷D (9)、astralanosaponin D (10)、大豆皂醇E (11)、3β,21α,24-三羟基-齐墩果-12-烯(12)、3β,22β,24,29-四羟基齐墩果-12-烯(13)、豌豆皂苷Ⅰ(14)、大豆皂醇B-3-O-β-D-吡喃葡萄糖醛酸基-(1→2)-β-D-吡喃葡萄糖基-...  相似文献   
46.
黄芪体外作用对贫血小鼠骨髓基质细胞分泌SCF的影响   总被引:12,自引:0,他引:12  
目的 研究黄芪注射液(AMI)对贫血小鼠骨髓基质细胞分泌干细胞因子(SCF)的影响。方法 在贫血小鼠骨髓基质细胞培养体系中,分别加入0.1mL不同浓度的AMI(终浓度分别为40mg/L,400mg/L)作为药物1组,药物2组,对照组加入等量的IMDM培养液,检测各实验组培养体系中骨髓成纤维细胞集落(CFU-F)数,同时,分别收集培养上清液,透析浓缩成冻干粉,经IMDM液稀释后作为条件培养液,分别加入到高增殖潜能的集落形成细胞(HPP-CFC)培养体系中,检测各实验组培养上清液中所含SCF的水平。结果 与对照组相比较,药物组的CFU-F数及骨髓基质细胞条件培养液(BMSCM)中SCF的水平均明显升高。结论 一定浓度的AMI可促进贫血小鼠骨髓CFU-F增殖。刺激其骨髓基质细胞分泌SCF。  相似文献   
47.
目的 探讨鱼油对急性坏死性胰腺炎胃肠道功能的影响及可能机制.方法 SD大鼠被分为三组:急性坏死性胰腺炎组(A组,n=8)、急性坏死性胰腺炎鱼油干预组(F组,n=8)和对照组(C组,n=8).观察5 d后各组大鼠胰腺组织病理变化.同时检测各组大鼠胃肠道食物残渣量及血浆超氧化物歧化酶SOD、谷胱甘肽过氧化物酶(GSH-Px)活力、D乳酸浓度和淀粉酶浓度.结果 病理学检查提示A组和F组均表现为严重的胰腺坏死,但F组的炎细胞浸润程度显著低于A组(P<0.01).与C组比较,A组胃肠道食物残渣分布出现异常,其D乳酸水平显著升高(P<0.01);F组胃肠道食物残渣分布与C组比较无统计学意义,D乳酸水平显著低于A组(P<0.01).A组GSH-Px、SOD显著低于C组(P<0.01);F组GSH-Px、SOD显著高于A组(P(0.01).结论 ANP时除表现为胰腺局部严重的炎症外,同时还并发存在胃肠道功能障碍及全身抗氧化防御系统损坏(GSH-Px、SOD是体内最重要抗氧化酶);应用鱼油干预可使ANP大鼠胰腺局部炎症减轻、ANP胃肠道功能障碍得以纠正,可能与其影响抗氧化酶系统有关.  相似文献   
48.
The importance of combining studies across vertebrates to provide insights into the functionality of hormone systems is considered, using recent advances in Urotensin II (UII) biology to illustrate this. The impact of genome analyses on understanding ligand and UII receptor (UT) structures is reviewed, noting their high conservation from fish to mammals. The early linkage of UII with fish osmoregulatory physiology drove our investigation of possible renal actions of UII in mammals. The kidney is a potential major source of UII in mammals and endogenous peptide appears to have tonal influence over renal excretion of water and electrolytes. Blockade of UII actions by administration of UT receptor antagonist, urantide, in anaesthetised rats, indicates that endogenous UII lowers renal filtration rates and excretion of water and ions. These effects are considered in relation to apparent association of UII with a number of human cardiovascular and renal disorders. Following up the sequencing of UT in mammals here we contrast the first fish UT sequences with those in other species. It is now evident that UT expression in fish osmoregulatory tissues, such as the gill and kidney, exhibits considerable plasticity in response to physiological challenge, providing an important component of the adaptive organismal responses. A number of areas of UII research, which will continue to benefit from moving questions between appropriate vertebrate groups, have been highlighted. These comparative approaches will yield improved understanding and further novel actions of this intriguing endocrine and paracrine system, so highly conserved across the vertebrate series.  相似文献   
49.
50.
目的:对横根费菜的组织形态进行鉴别,并建立横根费菜中没食子酸含量测定方法.方法:采集原植物,对该植物进行植物学及生药学的鉴定;采用HPLC-UV法,色谱柱为Hypersil C18柱(4.6 mm×250 mm,5μm);流动相:甲醇-体积分数为0.3%磷酸水溶液(94:6);检测波长:273 nm;流速:1.0 mL...  相似文献   
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