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51.
为建立检测鸡天然免疫相关受体(Ch-MDA5、Ch-TLR3和Ch-TLR7)及其相应配体(MAVS、TRIF和MyD88)的荧光定量PCR方法并评价其应用效果,设计和筛选特异性PCR引物,制备各基因的质粒标准品,绘制荧光定量PCR的标准曲线,并对方法的灵敏度、重复性和特异性进行检验。结果表明,所建立的检测方法敏感度高、特异性强、检测线性范围广、重复性好。应用建立的方法检测新城疫油乳剂灭活苗免疫SPF鸡后上述基因表达的变化,发现免疫后6h各基因的表达水平达到峰值,表明疫苗免疫迅速有效地激活了机体的天然免疫应答。建立了与鸡抗病毒感染天然免疫相关的3种细胞受体和相应配体的定量检测方法,可应用于病毒致病机制、鸡用新型疫苗、免疫增强剂以及抗病毒药物的研究与开发。  相似文献   
52.
AIM: To investigate the effects of rosiglitazone on fibroblast-like synoviocyte (FLS)-induced osteoclastogenesis in rheumatoid arthritis (RA) and the related mechanism. METHODS: RA-FLS were cocultured with peripheral blood monocytes from healthy volunteers in the presence of macrophage colony-stimulating factor (M-CSF) and rosiglitazone. Osteoclasts were assayed by tartrate-resistant acid phosphatase (TRAP) staining. Resorption lacunae area was identified by toluidine blue staining and quantified by image analysis software. The mRNA expression of RANKL and OPG was evaluated by real-time PCR, and the protein levels of RANKL, OPG, p-ERK, p-p38 and p-JNK were measured by Western blot. RESULTS: Compared with control group (without rosiglitazone treatment), rosiglitazone at concentration of 15 μmol/L significantly decreased the number of osteoclasts (P<0.01) and resorption lacunae area (P<0.05). The expression of RANKL at mRNA and protein levels was significantly down-regulated by rosiglitazone at concentration of 15 μmol/L, while the mRNA and protein expression of OPG was up-regulated (P<0.01). Rosiglitazone (15 μmol/L) significantly decreased the protein level of p-ERK (P<0.05), but not the protein level of p-p38 or p-JNK (P>0.05). CONCLUSION: Rosiglitazone inhibits RA-FLS-induced osteoclast formation and its resorption activity by down-regulating RANKL expression and ERK phosphorylation, suggesting that rosiglitazone may inhibit RA osteoclastogenesis and bone resorption.  相似文献   
53.
BACKGROUND: Chemokine expression in airway epithelium and bronchoalveolar lavage fluid (BALF) cells of horses with recurrent airway obstruction (RAO) is increased. HYPOTHESIS: For RAO-affected horses that are stabled and fed a pelleted ration, the addition of oral dexamethasone further improves pulmonary function and reduces inflammatory gene expression in pulmonary cells. ANIMALS: Twelve RAO-affected horses. METHODS: In a randomized cross-over experiment, the effect of feeding pellets in lieu of hay to stabled, RAO-affected horses was compared with the effect of feeding pellets and administering a 21-day decreasing dose regimen of oral dexamethasone on the expression (by kinetic polymerase chain reaction) of interleukin-8 (IL-8), chemokine (C-X-C motif) ligand 2 (CXCL2), IL-1beta, IL-6, and beta-actin in the BALF cells and of IL-8, CXCL2, 2 IL-1 receptor (IL-1R2), Toll-like receptor 4 (TLR4), and glyceraldehyde 3-phosphate dehydrogenase in the bronchial epithelium 2 days after the final dose. RESULTS: Both treatments reduced airway neutrophilia and breathing efforts but the addition of dexamethasone was associated with fewer treatment failures. Compared with feed changes alone, dexamethasone administration further reduced the expression of IL-8, CXCL2, and IL-1beta in the BALF cells 3.3-, 2.5-, and 4.7-fold, respectively. In the airway epithelium, both treatments were equally efficacious in reducing the expression of IL-8 and CXCL2 expression relative to pretreatment values, but either treatment failed to alter the expression of IL-1R2 and TLR4. CONCLUSIONS AND CLINICAL IMPORTANCE: For a rapid and consistent improvement in pulmonary function and a reduction in inflammatory gene expression of the BALF cells, a decreasing dose of oral dexamethasone in combination with feed alterations is more efficacious for horses that must remain stabled.  相似文献   
54.
病毒受体是决定病毒宿主特异性和组织嗜性的重要因素.利用原核细胞表达了猪口蹄疫病毒受体整合素β8亚基的配体结合域(LBD)片段,分离纯化目的蛋白后免疫兔,制备兔多克隆抗体.以含有猪β8亚基全长cD-NA的质粒为模板,经PCR扩增得到位于β8成熟肽氨基端的LBD基因片段,与带有GST标签的原核表达载体pGEX 4T-1相连,构建原核表达质粒pGEX/β8LBD,测序确认读码框正确后,将其转化感受态细胞BL21(DE3),以IPTG诱导表达重组β8LBD融合蛋白.通过SDS-PAGE和Western blot鉴定后提取包涵体,以电泳分离纯化的重组融合蛋白免疫新西兰白兔制备多克隆抗体,鉴定血清效价和特异性.结果显示,实现了重组猪β8LBD融合蛋白在大肠杆菌中的高效表达,SDS-PAGE显示分子量约为46 000,主要以包涵体形式存在于菌体中.制备的兔多克隆抗体效价达1∶12 800以上,该血清可与目的蛋白发生特异性反应.这将为进一步研究猪整合素β8亚基在宿主体内的分布及其在口蹄疫病毒致病过程中的作用奠定基础.  相似文献   
55.
金黄色葡萄球菌FnBP配体结合区基因的克隆及其原核表达   总被引:1,自引:0,他引:1  
[目的]克隆金黄色葡萄球菌FnBP配体结合区基因,并构建原核表达载体,进行原核表达:方法]设计引物,采用PCR方法扩增FnBP配体结合区基因,BA克隆后,构建了克隆质粒pMD18-FnBP。用BarnHI和EcoRI双酶切pMD18-FnBP和pET28a(+),将纯化的基因FnBP亚克隆至pET28a(+),构建重组表达质粒pET28a-FnBP,并将其转化至大肠杆茼感受态B121(DF3)中,IPTG诱导表达,并对表达产物进行分析。[结果]PCR扩增出1条约370hp的目的片段,表达产物经SDS-PAGE分析,在30kDa处出现了与目的蛋白一致的外源蛋白带.Westem blot分析表明该蛋白具有金黄色葡萄球菌的抗原性。[结论]已成功构建了FnBP配体结合区基因,并在原核细胞中表达。  相似文献   
56.
在水热条件下采用硝酸铜和2,4,6-三甲基吡啶为原料合成了两个新的配合物[Cu4(2,4,6-opyta)2(H2O)8](1)和[Cu4(2,4,6-opyta)2(H2O)6].2H2O(2),并对配合物的结构进行了X-射线单晶衍射分析.结果表明,两配合物互为超分子异构体,结构中都包含有[Cu2(2,4,6-opyta)2]基本单元,且均结晶于三斜晶系,P-1空间群,其晶胞参数分别为a=7.008 8(9),b=8.055 0(10),c=10.979 0(10),α=73.419(2)°,β=87.934(2)°,γ=85.127(2)°,V=591.86(12)3和a=6.980 2(7),b=7.067 6(7),c=13.234 6(14),α=82.698(2)°,β=76.977(2)°,γ=79.960(2)°,V=623.74(11)3.  相似文献   
57.
以2,6-双(2-溴乙酰基)溴苯和乙酰胺为原料,分别用传统加热法和微波加热法制得了钳形配体2-溴-1,3-双[4-(2-甲基)噁唑基]苯.结果表明,用微波加热法合成目标产物有显著优越性,可使产率从40%提高到85%,同时反应时间从3d缩短到15min.  相似文献   
58.
Proton consumption with phosphate adsorption on amorphous Fe (III) hydroxide (am-Fe(OH)3) was compared between two different pH-controlled conditions in a 0.1 mol dm-3 NaClO4 solution at initial pH values of 5.50 and 4.50, at 298±0.005 K.

The number of protons caused by phosphate dissociation was subtracted from the total number of protons consumed, then the amount of surface OH groups released by the ligand exchange reaction were determined. When a sequential acid titration by a pH-stat maintained pH values of the systems at initial pH values, the percentage of OH groups released during the ligand exchange reaction was almost constant, 29–37%. When the pH values of the systems increased with phosphate adsorption, the percentage of OH groups released by the ligand exchange reaction varied from -4.3 to 33%. The difference in the proton migration between the two pH-controlled conditions not only depended on the phosphate dissociation, but on the difference in the adsorption mechanism, i.e. the ratio of ligand exchange with OH groups to total phosphate adsorption.  相似文献   
59.
The effect of genistein (GEN) on the gene expression level of stromal cell-derived factor-1/CXCL-12 and early growth response gene-1 was studied in ovarian tissue of young and initially ageing (early stages in the ageing process) female rats. Forty, young female Sprague Dawley (SD) rats of 2–3 months old (200 ±20 g) and forty, initially ageing female SD rats of 10–12 months (490 ± 20 g) old were selected. According to the weight, rats were divided into control group, low-dose group (L), medium-dose group (M) and a high-dose group (H) and were given 15, 30 and 60 mg/kg GEN respectively. The positive control (Oestrogen) group was given 0.5 mg/kg diethylstilbestrol. The treatment lasted for 30 days. The mRNA expression of C-X-C motif chemokine ligand 12 (CXCL-12) and early growth response factor-1 (EGR-1) was measured by real-time PCR, and protein expression of EGR-1 was detected by Western blot. When compared to the negative control group (NC), the ovary/body weight ratio in the young rats decreased in the GEN group, but the difference was not significant. Similarly, compared with NC, the ovary/body weight ratio in the initially ageing rats also decreased with the increase in GEN concentration, but the decrease was significant in M and H groups (p < .01). The administration of GEN enhanced both the gene and protein expression levels of CXCL-12 and EGR-1 in the ovary. Pearson's correlation analysis showed a synergistic effect between CXCL-12 and EGR-1. Thus, we conclude that the effect of GEN on CXCL-12 and EGR-1 in the initially ageing group was obvious than that in the younger group.  相似文献   
60.
Neuronal nitric oxide synthase (nNOS) has been implicated in peripheral nerve lesions and regeneration. The CAPON adaptor protein interacts with the PDZ domain of nNOS, helping to regulate nNOS activity at post-synaptic sites in neurones, but it is not known whether its expression is altered in sciatic nerves after chronic nerve constriction injury. In the present study, the spatiotemporal expression of CAPON was determined in chronically constricted rat sciatic nerves. Similar to the level of protein expression, CAPON mRNA was significantly up-regulated for almost 5 weeks following sciatic nerve injury. Immunohistochemistry demonstrated that increased CAPON was found mainly in S-100-positive Schwann cells. In addition, co-immunoprecipitation demonstrated an interaction between CAPON and nNOS in Schwann cells and the interaction was enhanced in injured sciatic nerves. CAPON may be involved in peripheral nerve regeneration through regulation of nNOS activity.  相似文献   
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