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41.
Seventeen newborn lambs were fed with untreated colostrum (group A) and 18 lambs were fed with colostrum treated by heat (56 °C, 30 min) (group B). Blood samples were obtained at seven time points from day 0 to 38 of life. Clinical status and body weight were recorded and serum protein fractions and IgG levels were determined in blood. Phagocytosis of neutrophils from the lambs and opsonic capacity of their serum were examined using a flow cytometry method. As an indicator of in vivo cellular immunity, reactions to intradermal injection of phytohemagglutinin (PHA) were examined at 8 and 16 days of age. There were no clinical signs of disease and no significant differences in body weight between groups. Lambs from group B had lower total protein initially and lower γ-globulin and IgG levels until day 32 compared to lambs from group A (P < 0.01). Heat treatment of colostrum had no significant effect on serum opsonic capacity or phagocytosis by neutrophils and these functions increased with age. However, responses to PHA in lambs from group B were lower (P < 0.01) than group A at day 8 of life, but not at day 16, suggesting that cellular immunity was affected by the treatment of colostrum. These results showed that colostrum treated by heat impaired cellular and IgG levels in lambs, but not phagocytic function. However, these changes did not affect the health or performance of the lambs.  相似文献   
42.
AIM:To investigate the antitumor activity and mechanism of Paecilomyces tenuipes polysaccharide(PTPS).METHODS:PTPS-I was obtained by water extraction and alcohol precipitation, and purified by DEAE-cellulose and Sephadex G-100 chromatography. Human erythroleukemia cell line K562, laryngocarcinoma cell line Hep2 and hepatic carcinoma cell line SMMC-7721were co-cultured with PTPS-I or the conditioned medium which prepared with PTPS-I-stimulated human mononuclear cells (PTPS-I-MNC-CM), and the proliferation of tumor cells was determined. The cell counting kit-8 (CCK-8) was used to determine the proliferation of MNCs. The FQ-RT-PCR was applied to investigate the expression of TNF-α and IL-6 mRNA in MNCs. RESULTS:PTPS-I-MNC-CM inhibited the proliferation of K562, Hep2 and SMMC-7721 cells in vitro (P<0.01). Cytotoxicity of PTPS-I against K562, Hep2 and SMMC-7721 cells was not observed (P<0.01). PTPS-I stimulated the proliferation of MNCs (P<0.01) and significantly enhanced the expression of TNF-α and IL-6 mRNA in MNCs (P<0.05, P<0.01). CONCLUSION:The results suggest that PTPS-I is an immunomodulator and its antitumoral activity is through the immunomodulatory mechanism rather than the direct cytotoxicity against tumor cells.  相似文献   
43.
The present study was an investigation into the role of T lymphocytes in the killing of antigen-sensitized macrophages (MΦ) in bovine brucellosis. Following confirmation of bovine T lymphocyte cell lines derived from Brucella abortus Strain 19 vaccinated steers as antigen-specific in proliferation studies using various antigens, we adapted an apoptosis assay for evaluation of cytotoxicity by these bovine T cells against autologous monocyte-derived macrophages (MDMΦ) as target cells. Various B. abortus antigen preparations were tested including whole γ-irradiated B. abortus bacteria (γBA), a soluble cytosolic protein fraction and a membrane-associated protein fraction. Both polyclonal and cloned T lymphocyte cell lines exhibited cytotoxicity against MDMΦ targets in an antigen-specific fashion. Polyclonal and cloned T lymphocyte cell lines demonstrated cytotoxic responses to varying degrees against B. abortus antigens regardless of whether the antigen used was whole nonviable bacteria, a soluble protein extract or a membrane-associated fraction of extracted bacteria. To further develop correlation of these responses to an in vivo host defense mechanism, cytotoxicity was evaluated using target cells that had been infected with live B. abortus S19 or B. abortus Strain 2308. Cytotoxic responses were also demonstrated consistently against infected targets with either strain of B. abortus although in most cases, cytotoxicity was higher against target cells sensitized with γBA compared to those infected with live bacteria. Cloned T lymphocyte cell lines were all CD4+, CD8 cells indicating that the observed cytotoxic responses were most likely due to an inflammatory Th1 response and may represent an important host defense mechanism induced by vaccination with live attenuated strains of B. abortus in cattle.  相似文献   
44.
微量元素铜的营养与免疫研究进展   总被引:1,自引:0,他引:1  
从铜缺乏、中毒、营养需要及其标识等方面综述铜的营养特性和生物学功能研究进展。在此基础上结合营养免疫学方面的研究,详述有关铜影响动物免疫功能的研究结果。  相似文献   
45.
The efficacy and safety of a recombinant Taenia ovis protein was tested in sheep using 13 different adjuvant formulations, including oil adjuvants, aluminium salts, saponin, Iscoms and DEAE-dextran. The oil adjuvants, saponin and DEAE-dextran gave the highest antibody responses and greatest degree of protection against challenge infection with T. ovis eggs. Duration of immunity studies with a saponin based vaccine showed that highly significant protection (>90% reduction of cyst numbers) was achieved when sheep were challenge infected one month after immunisation. Significant protection (79%) was still present when sheep were challenged 6 months after immunisation. The optimum dose for this batch of saponin was 10 mg, which stimulated a peak antibody titre of 38,400, 4 weeks after immunisation and did not cause injection site reactions. Dialysed saponin was shown to retain its adjuvant properties and allowed an increase in dose to 30 mg without site reaction, resulting in a peak antibody titre of 51,200.  相似文献   
46.
饲粮铬对0—3周龄肉鸡生长,血清生化特性和免疫功能的影响   总被引:29,自引:2,他引:27  
用1日龄Arbor Acres(AA)商品代肉公鸡384只,研究饲粮添加铬源与铬水平对00-3周龄肉鸡生长,血清生化特性和免疫功能的影响。试鸡按体重随机分成8组,分别喂以添加铬的玉米-豆粕型基础饲粮(含铬0.34mg/kg)及这种基础饲粮分别添加0.4,2.0,10.0mg/kg铬分别源于三氯化铬和酵母铬的饲粮以及20.0mg/kg铬源于三氯化铬的饲粮。  相似文献   
47.
采用单因子实验设计方法,进行了饲料中添加维生素E对美国红鱼生长(存活率、特定生长率和饲料效率)和非特异性免疫相关指标(血清中溶菌酶活性、血清总补体活性和超氧化物岐化酶(SOD)活性)影响的研究,设计了5个不同维生素E水平(0.1、25.3、51.0、102.8和203.2mg/kg)的等氮等能饲料,对美国红鱼进行为期56d的生长实验,每个水平3个重复,每个养殖单元放养初始体重为151g左右的美国红鱼20尾。饲养实验在海水网箱(1.5m×1.0m×1.0m)中进行。结果表明,随着饲料维生素E含量增加,美国红鱼饲料效率、特定生长率和成活率显著提高,美国红鱼最佳生长性能的饲料维生素E添加量为102.8mg/kg;美国红鱼血清溶菌酶和血清总补体活性随着维生素E的添加量的增加而显著升高,并且维生素E的添加量达到最高值102.8和25.3mg/kg,随后变化不明显;美国红鱼血清SOD活性随维生素E添加量的增加而显著升高,并且含量在102.8mg/kg达到最高值,随后显著下降。综上所述,美国红鱼维生素E的适宜添加量为102.8mg/kg。  相似文献   
48.
共轭亚油酸对大黄鱼免疫功能的影响   总被引:1,自引:0,他引:1  
1 500尾大黄鱼(Pseudosciaena crocea)随机分为5个处理,分别饲喂冰鲜鱼(D1组)、添加5%鱼油日粮(D2组)、共轭亚油酸(CLA)水平为1%(D3组)、2%(D4组)、4%(D5组)日粮.饲喂10周后,通过测定脾脏重、脾体指数、溶菌酶、补体C3、C4、免疫球蛋白IgM浓度等免疫指标,研究不同水平CLA日粮对大黄鱼免疫功能的影响.结果表明,在大黄鱼日粮中添加CLA可以影响其免疫器官-脾脏,添加CLA组使得大黄鱼脾体指数高于未添加CLA的对照组.虽然日粮中添加CLA对于补体C3、C4没有显著影响,但是对于溶菌酶和免疫球蛋白IgM有明显的影响.在大黄鱼日粮中添加CLA可以在一定程度上改善大黄鱼的免疫性能,对于其抗细菌、抗病毒能力有一定提高.  相似文献   
49.
microRNA(miRNA)是一类内源性、长度约为22个核苷酸的非编码小单链RNA分子,由具有发夹结构的70?90个碱基的单链RNA前体经过Dicer酶加工而成。本研究使用荧光实时定量PCR (Quantitative Real-Time PCR, qRT-PCR)方法,研究了miRNA-223(miR-223)在半滑舌鳎(Cynoglossus semilaevis)各健康组织、鳗弧菌(Vibrio anguillarum)感染后各时间点的免疫组织以及不同病原类似物刺激后头肾细胞中的表达模式。结果显示,miR-223在半滑舌鳎各组织中均有表达,在头肾中表达量最高,在脑和血液中的表达量极低。鳗弧菌感染3组样品4种免疫组织,miR-223表达变化显著,感染后20 h内,鳗弧菌诱导miR-223上调表达。鳗弧菌感染后半滑舌鳎免疫组织miR-223表达变化规律显示,鳗弧菌感染2、6、12、24、48、72、96和168 h后,miR-223在肝、肠、脾、头肾4种组织中出现差异表达。其中,miR-223在半滑舌鳎肝、脾、头肾中表达上调,在肠中表达下调。用LPS、poly I:C、PGN、RGNNV感染半滑舌鳎头肾细胞后,发现经LPS、RGNNV诱导后miR-223上调表达,poly I:C、PGN诱导后miR-223下调表达。研究结果表明,miR-223参与了半滑舌鳎免疫应答过程。本研究结果有助于了解miRNA在半滑舌鳎对病原刺激免疫应答过程中的作用以及半滑舌鳎与病原相互作用中miRNA参与调控的机制。  相似文献   
50.
在基础饲料中分别添加0、10%、20%、30%、40%的玉米干酒精糟及其可溶物(Dried distiller's grains with solubles,DDGS),配制成5种等氮等能的实验饲料(DDGS0、DDGS10、DDGS20、DDGS30 和DDGS40),饲喂初始体重为(9.69±0.28)g的刺参56 d,研究玉米DDGS作为替代蛋白源对其生长、体成分及免疫指标的影响.结果显示,随着玉米DDGS添加水平的升高,刺参增重率和特定生长率略有下降,但各组间差异不显著(P>0.05).各实验组刺参体壁指数、肠道指数、肠长比以及体壁水分、粗蛋白、粗脂肪和粗灰分含量均不受玉米DDGS添加的影响(P>0.05).体腔液中溶菌酶的活性呈先上升后稳定的趋势,其中,DDGS20和DDGS40组显著高于DDGS0和DDGS 10组(P<0.05),DDGS30组与其他各组无显著差异(P>0.05).酸性磷酸酶的活性呈先上升后下降的趋势,在DDGS20组达到最大值,其中,DDGS20组显著高于其他各组(P<0.05),DDGS40组显著高于DDGS0组(P<0.05),其他各组间无显著差异(P>0.05).酚氧化酶的活性随着DDGS添加量的增加呈上升趋势,各添加组均显著高于DDGS0组(P<0.05),DDGS40组显著高于DDGS 10组(P<0.05),其他各组间无显著差异(P>0.05).饲料中添加玉米DDGS对体腔液中碱性磷酸酶和超氧化物歧化酶的活性无显著影响(P>0.05).本研究表明,饲料中添加0-40%的玉米DDGS均不影响刺参的生长和体壁成分,且添加20%-40%的玉米DDGS能提高刺参体腔液中免疫酶的活性.  相似文献   
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