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31.
细胞因子是一类具有广泛生物学效应的可溶性多肽.动物卵巢的多种组织中都有IL-1、TNF等细胞因子及其受体存在,因此它们在卵巢生殖活动中所起的作用越来越被人们重视.细胞因子可通过自分泌或旁分泌途径影响卵泡、黄体形态和功能.  相似文献   
32.
白细胞介素12因其独特的生物学功能自发现以来就成为研究热点。它能够通过刺激NK细胞活化、增殖及产生IFN-γ而改变Th1/Th2平衡向Th1方向发展,在细胞介导的免疫中发挥了重要作用,因此在抗肿瘤、抗病毒、抗寄生虫等方面有广阔的应用前景,并成为一种良好的疫苗免疫佐剂。  相似文献   
33.
李春香 《安徽农业科学》2009,37(3):1096-1097
[目的]研究尖海龙提取物的免疫调节活性。[方法]制备尖海龙提取物,用密度梯度离心法分离人外周血淋巴细胞(PBMC),将海龙提取物作用于PBMC,观察PBMC的形态、细胞增殖率,同时检测经尖海龙提取物诱导后细胞因子的生成。[结果]结果表明,尖海龙提取物作用后PBMC圆形、发亮,正常生长并有增殖,随着时间的延长,细胞出现多形的活化状态;经尖海龙提取物诱导的效应细胞中可检测出IL-2和TNF-τ细胞因子。[结论]尖海龙提取物具有免疫调节活性,在癌症的治疗与预防方面具有应用价值。  相似文献   
34.
The extremely severe epidemic situation of coronavirus disease 2019 (COVID-19) outbreak around the world with high infectiousness and rapid spread has become a public health emergency of international concern. The disease is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and cytokine storm is an important pathological manifestation. Related studies have shown that cytokine storm and dysregulation of host immune responses characterized by lymphopenia are important mechanisms for the pathogenesis of severe COVID-19. The immune response disorder of COVID-19 is closely related to T helper 17 cell/regulatory T cell (Th17/Treg) immune imbalance. SARS-CoV-2 infection leads to excessive activation of lung immune cells, forming a cytokine storm dominated by interleukin-6 (IL-6). Then, the Th17/Treg immune balance is broken, forming a vicious circle, which eventually promotes the rapid aggravation of the disease. Finally, COVID-19 progresses into acute respiratory distress syndrome, and even respiratory failure until death. Therefore, it is more important to discuss the prevention and treatment of COVID-19 from the perspective of immune imbalance. On the view of treatment, before effective antiviral drugs and vaccines are successfully developed, we should pay attention to immune regulation for severe and critically ill patients. Treatments with inflammatory factor blockers, glucocorticoids, recovered plasma and traditional Chinese medicine have certain immunomodulatory effect. This article discusses the pathogenesis of COVID-19 based on Th17/Treg immune imbalance, and elaborates on immunomodulatory therapy, aiming to provide reference for the prevention and treatment of COVID-19 and drug development.  相似文献   
35.
We evaluated the temporal relationship between neutrophil numbers and plasma granulocyte colony-stimulating factor (G-CSF) concentrations in dogs infected with canine parvovirus, a common infectious cause of neutropenia. G-CSF is produced in response to neutropenia, infection, or inflammation, and results in the production and release of neutrophils from the bone marrow. Adequate numbers of functional neutrophils are necessary for protection from infection, and the timely production of G-CSF is a crucial response to certain diseases. The relationship between peripheral neutrophil numbers and plasma G-CSF concentrations during the course of an infectious disease characterized by neutropenia has not been described previously in dogs. Eight mixed-breed puppies were given an oronasal challenge with canine parvovirus, and peripheral neutrophil numbers as well as plasma G-CSF concentrations were measured daily. G-CSF was not detectable in plasma of any dog before the onset of neutropenia, but G-CSF became detectable just after the onset of neutropenia in the 7 dogs that developed clinical illness. Neutropenia persisted or worsened for at least 2 days after plasma G-CSF became detectable in all 7 dogs. Neutrophil nadir, the highest plasma G-CSF concentrations, and the most severe clinical illness occurred concurrently in most dogs. Although 1 dog died while still neutropenic, plasma G-CSF concentrations declined before resolution of neutropenia in the other 6 dogs, and were again below the limits of detection in 5 of the 6 dogs at the time of resolution.  相似文献   
36.
The present study sought to quantitatively examine mucosal inflammatory and immune responses in dogs with gastritis and the relationship of these responses to infection with Helicobacter. Gastric biopsies from 30 dogs were evaluated for B- and T-lymphocytes, neutrophils, eosinophils, macrophages, and mast cells. Mucosal atrophy, fibrosis, cellularity, and severity of gastritis were graded qualitatively. Messenger-RNA (mRNA) for actin, interleukin-1beta (IL-1beta), IL-4, IL-8, and IL-10, transforming growth factor beta (TGF-beta), and interferon gamma (IFN-gamma) was quantified by polymerase chain reaction (PCR). The presence of Helicobacter spp. was determined by urease activity, histology, PCR, and enzyme-linked immunosorbent assay. mRNA for IL-1beta, IL-8, IL-10, TGF-beta, and IFN-gamma was detected in most dogs. IL-4 mRNA was detected in only 1 dog. Correlations were observed for IL-1beta versus IL-8 and IL-10; IL-8 versus IL-10, IFN-gamma, and TGF-beta; and IL-10 versus IFN-y. Mucosal pathology was related to cytokine mRNA expression (neutrophils to IL-8 and IFN-gamma, macrophages and lymphocytes to IFN-gamma, and fibrosis to IL-1beta). Gastritis was categorized as lymphoplasmacytic in all dogs, and its histologic severity correlated with atrophy, infiltration with lymphocytes and macrophages, and expression of IL-10 and IFN-gamma. Of the dogs examined, 76.7% were infected with Helicobacter spp. Infection was associated with increased expression of TGF-beta and fibrosis. Circulating anti-Helicobacter immunoglobulin G titers were higher in uninfected than infected dogs. We conclude that lymphoplasmacytic gastritis in dogs is characterized by concurrent activation of proinflammatory and immunomodulatory cytokines, with increased mRNA expression related to mucosal pathology. No significant associations between Helicobacter infection and proinflammatory cytokine expression, severity of gastritis, or differences in the pathogenicity of different Helicobacter spp. were found.  相似文献   
37.
IL-27 is the newest member of the IL-12 cytokine family and plays an important role in the immune regulation. It is composed of two subunits, p28 and EBV-induced gene 3(EBI3). Although human and mouse IL-27 p28 genes have been cloned, pig IL-27 p28 gene has not ever been reported. In the present study, we have cloned and characterized the full-length cDNA of IL-27 p28 from pig. The open reading frame of pig IL-27 p28 gene is 720 bp, which encodes a protein of 239 amino acids with a predicted molecular mass of 26.6 kDa. The deduced amino acid sequence of pig IL-27 p28 showed a high degree of homology to human (63%) and mouse (58%). It was a 4-helix cytokine and belonged to 4-helix cytokine superfamily. Pig IL-27 p28 has one transmembrane region, one signal peptide, and one N-glycosylation site, two Protein kinase C phosphorylation sites, three Casein kinase II phosphorylation sites and one N-myristoylation site. For the expression of pig IL-27 p28 protein in a eukaryotic expression system the recombinant plasmid was constructed. The expression of pig IL-27 p28 in mammalian cells were confirmed by flow cytometry analysis, immunofluorescence and Western blot. The analysis also confirmed a cross reactivity with anti-mouse IL-27 p28 antibody. This is the first report of cloning and characterization of IL-27 p28 in pig.  相似文献   
38.
T helper (Th) cells produce signature cytokine patterns, induced largely by intracellular versus extracellular pathogens that provide the cellular and molecular basis for counter regulatory expression of protective immunity during concurrent infections. The production of IL-12 and IFN-γ, for example, resulting from exposure to many bacterial, viral, and protozoan pathogens is responsible for Th1-derived protective responses that also can inhibit development of Th2-cells expressing IL-4-dependent immunity to extracellular helminth parasites and vice versa. In a similar manner, concurrent helminth infection alters optimal vaccine-induced responses in humans and livestock; however, the consequences of this condition have not been adequately studied especially in the context of a challenge infection following vaccination. Demands for new and effective vaccines to control chronic and emerging diseases, and the need for rapid deployment of vaccines for bio security concerns requires a systematic evaluation of confounding factors that limit vaccine efficacy. One common albeit overlooked confounder is the presence of gastrointestinal nematode parasites in populations of humans and livestock targeted for vaccination. This is particularly important in areas of the world were helminth infections are prevalent, but the interplay between parasites and emerging diseases that can be transmitted worldwide make this a global issue. In addition, it is not clear if the epidemic in allergic disease in industrialized countries substitutes for geohelminth infection to interfere with effective vaccination regimens. This presentation will focus on recent vaccination studies in mice experimentally infected with Heligmosomoides polygyrus to model the condition of gastrointestinal parasite infestation in mammalian populations targeted for vaccination. In addition, a large animal vaccination and challenge model against Mycoplasma hyopneumonia in swine exposed to Ascaris suum will provide a specific example of the need for further work in this area, and for controlled field studies to assess the impact of other similar scenarios.  相似文献   
39.
The cDNAs of two proinflammatory cytokines viz., IL-6 and TNF-α from dromedarian camels were amplified by PCR using bactrian camel sequences and subsequently cloned for sequence analysis. Relationship based on amino acid revealed that dromedarian camel IL-6 shared 99.5% identity both at nucleotide and amino acid level with bactrian camel IL-6 and in case of TNF-α, the identity of dromedarian camel was 99.4% and 99.1% at nucleotide and amino acid level, respectively with that of bactrian camel. Phylogenetic analysis based on their amino acid sequences indicated the close relationship in these cytokine genes between dromedarian camel and other members of camelids.  相似文献   
40.
旨在研究口服复方人参皂苷纳米乳对抗原免疫效果的影响。将小鼠分为正常对照组、卵清白蛋白(OVA)对照组、空白纳米乳组、盐酸左旋咪唑纳米乳组、人参皂苷纳米乳组、人参皂苷-盐酸左旋咪唑水溶液组和复方人参皂苷纳米乳组(高、中、低剂量),皮下注射OVA抗原2次,在首次和第2次注射前3d连续灌胃给药,第2次注射后14d,测定血清(IgG、IgG1和IgG2a)抗体水平、脾细胞因子(IFN-γ和IL-4)水平以及脾淋巴细胞增殖刺激指数。结果表明,复方人参皂苷纳米乳中剂量(50mg·kg-1)组IL-4、IgG和IgG1水平显著或极显著高于复方人参皂苷纳米乳低剂量组和盐酸左旋咪唑纳米乳组,IFN-γ、IgG2a及OVA诱导脾淋巴细胞增殖刺激指数显著或极显著高于人参皂苷纳米乳组、人参皂苷-盐酸左旋咪唑水溶液组、盐酸左旋咪唑纳米乳组、复方人参皂苷纳米乳高剂量组和低剂量组。口服复方人参皂苷纳米乳能诱导OVA免疫小鼠产生Th1/Th2混合型免疫反应,表明人参皂苷和盐酸左旋咪唑能协同增强小鼠的细胞免疫和体液免疫功能。  相似文献   
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