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61.
采用间接ELISA法检测雏鸡初次及二次感染毒害艾美耳球虫(Eimerianecatrix)后血清免疫球蛋白含量的动态变化。结果表明,雏鸡初次感染E.necatrix 后10 d~ 14 d血清IgG, IgM, IgA 含量开始增加,16 d~18 d达到峰值;雏鸡二次攻击性感染E.necatrix 后2 d~7 d,其血清的上述3种免疫球蛋白含量均不同程度低于初次感染雏鸡,随后开始回升,至10 d~14 d明显高于相应对照及初次感染雏鸡。血清抗体,特别是IgG介导的体液免疫,在雏鸡抵抗E.necatrix初次及二次感染中发挥了重要作用。  相似文献   
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63.
A trial was conducted to observe the immediate and chronic effects in goats of dexamethasone administration on the bronchus-associated lymphoid tissue (BALT) response to intranasal administration of formalin-killed Pasteurella haemolytica A2. Twenty-four goats were divided into four groups. Those in group 1 were injected intramuscularly with 1 mg/kg dexamethasone on three consecutive days, followed by intranasal exposure to formalin-killed P. haemolytica A2 one day after the last dexamethasone treatment. The goats in group 2 were similarly injected with dexamethasone followed by intranasal exposure to formalin-killed P. haemolytica A2 21 days after the last dexamethasone treatment. The animals in group 3 were exposed intranasally to formalin-killed P. haemolytica A2 without prior dexamethasone treatment. The animals in group 4 were untreated controls. The intranasal exposures to formalin-killed P. haemolytica A2 were repeated 2 weeks later. Intranasal exposure to formalin-killed P. haemolytica 1 day after dexamethasone treatment further reduced the number and size of BALT compared to the untreated control. Significantly (p<0.01) more reduction of BALT occurred in goats exposed to formalin-killed P. haemolytica A2 21 days after dexamethasone treatment. On the other hand, intranasal exposure of goats without prior dexamethasone treatment stimulated the BALT compared to the untreated controls.  相似文献   
64.
Experiments were undertaken in six Holstein-Friesian cattle to determine whether secretory IgA (SIgA) could be transported from serum into exocrine body fluids. Preliminary data indicated that when IgG1, IgG2, IgM and SIgA were administered i.v., only SIgA and IgG1 appeared in bile 90 min later at concentrations equal to or exceeding those in serum at the same time. Two hours post-injection, 70% of the SIgA recovered in bile was intact however only 30% co-precipitable with anti-secretory component (SC) while >90% of the administered IgA was precipitated by this method. All recovered IgG1 was of low molecular weight. More detailed studies indicated that the IgA recovered in bile 7 h post-injection or in milk 3 h post-injection, was predominately lower molecular weight than intact SIgA. Most of this low molecular weight radioactivity was TCA precipitable and ca 50% was dialyzable; these data indicate that TCA-precipitability is an inadequate criterion for determining whether intact SIgA is transported. The radioactivity recovered in parotid saliva was almost entirely non-TCA precipitable and dialyzable. Almost all SIgA recovered in bovine serum remained intact and had a of 15.7 h. When transport into milk and bile was calculated from total, recovered radioactivity (i.e. 29% and 2.7, respectively), data compared favorably with those conducted in sheep in which dimeric IgA (without SC) was administered i.v. When we calculated transport on the basis of recovered intact IgA, only 1.47 and 0.54% of the injected dose had been transported into milk and bile, respectively, 24 h later. Most IgA in ruminant bile may be of serum origin although the same appears to be unlikely for the IgA in milk.  相似文献   
65.
The effect of a commercially available dietary casein phosphopeptide preparation, CPP‐III, consisting mainly of bovine αs2‐casein (1–32) and β‐casein (1–28) on the development of allergic symptoms mediated by IgE antibody was investigated in NC/Jic Jcl mice. No significant difference was observed in the change in mean bodyweight between mice given a diet of a mixture of ovalbumin and CPP‐III (CPP‐III‐added diet) and those given a diet of ovalbumin alone (control diet) as a protein source. Total allergic score of five mice given the CPP‐III‐added diet was less than half that of those given the control diet for 13 weeks. Levels of intestinal total and ovalbumin‐specific immunoglobulin (Ig)A were significantly higher in the CPP‐III‐added diet group than in the control diet group, while the serum ovalbumin‐specific IgE level was significantly smaller in the former. The production of interleukin (IL)‐6 by spleen cells from mice that ingested the CPP‐III‐added diet for 13 weeks was obviously higher than that by spleen cells from mice administered the control diet, while the formation of IL‐4 by spleen cells from the former mice was significantly lower than that by the latter mouse. These results suggest that the oral ingestion of CPP‐III may be beneficial in reducing allergic symptoms mediated by IgE antibody.  相似文献   
66.
为建立检测猪乳汁中抗猪染性胃肠炎病毒(TGEV)Ig A抗体的间接ELISA方法,本研究以TGEV重组N蛋白为包被抗原,以辣根过氧化物酶标记羊抗猪Ig A为检测抗体,并采用方阵法确定包被抗原和待检乳汁的最佳工作浓度,对各种反应条件进行优化,建立了猪乳汁中TGEV Ig A抗体的间接ELISA检测方法。该方法检测稀释160倍的阳性乳清仍呈阳性;与猪流行腹泻和猪轮状病毒感染阳性乳清无交叉反应;批内和批间变异系数均小于10%。利用建立的ELISA方法与间接免疫荧光方法分别对134份临床样品进行检测,阳性检出率分别为58.2%(78/134)和59.7%(80/134),总符合率为85.6%。本研究建立的检测方法能够有效评估乳汁中TGEV Ig A抗体的水平。  相似文献   
67.
Wildebeest IgA was isolated from nasal secretions and precolostrum. It was indentified by cross-reaction with anti-human and anti-bovine IgA sera.

Nasal secretions collected from wildebeest calves over 3 months old had malignant catarrhal fever virus neutralizing antibody activity. They also contained specific IgA to the virus as detected by indirect immunofluorescence. It is suggested that production of malignant catarrhal fever virus specific IgA in the nasal cavity, contributes to the elimination and cassation of the virus shed in the nasal secretions of wildebeest calves over 3 months. old.  相似文献   

68.
AIM To investigate the effects of Triptergium wilfordii multiglucoside (TWM) on intestinal flora and immune function in IgA nephropathy (IgAN) rats based on core 1 β1,3-galactosyltransferase (C1GALT1) and its chaperone protein Cosmc (C1GALT1/Cosmc pathway). METHODS The rat model of IgAN was established, and the animals were randomly divided into model group (IgAN group), dexamethasone (Dex) group and TWM group. Normal rats served as normal control (NC) group. The levels of serum creatinine (SCr) and blood urea nitrogen (BUN), 24-hour urinary total protein (24 h UTP) and the number of urinary red blood cells were measured by automatic biochemical analyzer. The levels of serum IgA1, and plasma tumor necrosis factor-α (TNF-α), B-cell activating factor (Baff) and interleukin-17 (IL-17) were detected by ELISA. The level of galactose-deficient IgA1 (Gd-IgA1) was detected by Vicia villosa lectin affinity ELISA. The intestinal colony was cultured in selective bacterial medium. The ratio of CD4+ CD25+ regulatory T cells (Treg) to CD4+ T cells (Treg proportion) in peripheral blood mononuclear cells (PBMC) was detected by flow cytometry.Western blot was used to determine the protein expression of C1GALT1 and Cosmc in intestinal mucosa. RESULTS Compared with NC group, 24 h UTP, the number of urinary red blood cells, SCr, BUN, serum IgA1 and Gd-IgA1, the numbers of Enterobacteriaceae, Enterococcus and Bacteroides, and the levels of TNF-α, Baff and IL-17 in plasma in IgAN group were significantly increased (P<0.05), while the numbers of Bifidobacteria and Lactobacilli, the Treg proportion in PBMC, and the protein expression levels of C1GALT1 and Cosmc in intestinal mucosa were significantly decreased (P<0.05). Compared with IgAN group, 24 h UTP, the number of urinary red blood cells, SCr, BUN, serum IgA1 and Gd-IgA1, the numbers of Enterobacteriaceae, Enterococcus and Bacteroides, and the levels of TNF-α, Baff and IL-17 in plasma in Dex group and TWM group were significantly reduced (P<0.05), and those in TWM group were lower than those in Dex group (P<0.05). Moreover, the numbers of Bifidobacteria and Lactobacilli, the Treg proportion in PBMC, and the protein expression levels of C1GALT1 and Cosmc in intestinal mucosa were significantly elevated (P<0.05), and those in TWM group were higher than those in Dex group (P<0.05). CONCLUSION TWM reduces the abnormal glycosylation level of IgA in IgAN rats by promoting the activation of C1GALT1/Cosmc pathway, and attenuates the intestinal flora disorder and immune dysfunction in IgAN rats, thus exerting the therapeutic effect.  相似文献   
69.
本文主要研究寡果糖对人源菌群仔猪肠道中IgA和IgG分泌细胞的影响。通过无菌剖腹产获取15头无特定病原菌(specific pathogen free,SPF)仔猪,随机分为三组。第一组为SPF组,经口灌服磷酸钠缓冲液(内含10%甘油)以示对照;第二组为人源菌群(human flora-associated,HFA)组,经口服途径接种人源菌群;第三组为寡果糖(fructo-oligosaccharides,FOS)组,口服途径接种人源菌群且灌喂寡果糖。仔猪饲养于屏障系统内,无菌条件下人工哺育45天。应用免疫组织化学方法进行研究。结果表明:(1)所有仔猪小肠和结肠的固有层中均分布有IgA和IgG分泌细胞。(2)IgA和IgG分泌细胞在十二指肠中分布最多,随着肠段的向后推移IgA和IgG分泌细胞数量有逐渐下降趋势。(3)HFA组和FOS组IgA分泌细胞数量在回肠显著高于SPF组(P<0.01);十二指肠中HFA组IgG分泌细胞数量显著高于SPF组(P<0.01)。(4)FOS组IgA分泌细胞数量在空肠显著高于HFA组外(P<0.05),其他肠段总体上低于HFA组,但差异不显著。本结果提示给新生仔猪接种人源菌群能促进仔猪肠道中IgA和IgG分泌细胞的发育,而寡果糖使肠道IgA和IgG分泌细胞数量呈现下降的趋势。  相似文献   
70.
E. coli infection of broilers can result in systemic diseases and productivity losses. Use of antimicrobials against this condition is common but other approaches, such as vaccination, are gaining ground. Anecdotal field reports indicate that intestinal health is improved unspecifically following E. coli live vaccination. We hypothesized that the intestine may be an important site for the functionality of the vaccine. Vaccine effects on the intestine were assessed. Spray vaccination induced marked alterations of the caecum microbiota of broilers within 3 days, and this effect gradually waned. However, T cell activation occurred in the spleen, but not in caecal tonsils, and anti-E. coli IgA was concentrated in the respiratory mucosae. Accordingly, IL-6 mRNA was produced in the lungs following immunization. Overall, these data are an initial indication that any vaccine-induced effects on the intestine are greatly associated with the microbiota. However, immunity conferred by vaccination is not primarily induced in gut-associated lymphoid tissues.  相似文献   
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