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91.
92.
Tumor necrosis factor (TNF)-alpha is thought to be one of the cytokines that account for bovine leukemia virus (BLV)-induced B-cell lymphoproliferative disorder, however, information on TNF-alpha expression in B-cells is limited. In this study, the expression of TNF-alpha in IgM(+) B-cells from BLV-infected sheep with or without lymphocytosis was determined. Freshly isolated IgM(+) B-cells from three sheep with lymphocytosis constitutively transcribed TNF-alpha mRNA. Although TNF-alpha mRNA expression in IgM(+) B-cells was transiently up-regulated after cell culture, TNF-alpha mRNA expression was markedly higher in lymphocytotic sheep when compared to that of non-lymphocytotic sheep or uninfected sheep. Expression of membrane-bound TNF-alpha on IgM(+) B-cells was also augmented in lymphocytotic sheep. TNF-alpha expression in lymphocytotic sheep may support the proliferation of B-cells.  相似文献   
93.
This paper reports on a study comparing three spectroscopic measurements (interactance, reflectance, and transmittance) in the Vis/NIR range for the detection of internal insect infestation with different damaged levels in jujubes (Hovenia acerba Lindl.). Stepwise discriminant analysis was used to derive the discriminant functions based on the effective wavelengths that had maximum discriminatory potential for the different internal conditions. The results show that both interactance in the long-wave NIR (LWNIR) and transmission in the visible and short-wave near-infrared (VSWNIR) wavelength ranges have an obvious advantage over reflectance for every range in completely distinguishing infested from intact jujubes. However, interactance and reflectance in the VSWNIR wavelength range exhibited higher classification accuracies in sorting severely damaged jujubes from slightly infested and intact samples. Furthermore, transmission had clear advantages over both interactance and reflectance for distinguishing slightly infested jujubes from intact jujubes in the VSWNIR range.  相似文献   
94.
Immunohistochemistry was performed to assess whether oxidative stress and/or denatured proteins play roles in the pathogenesis of canine degenerative myelopathy (DM). Two Pembroke Welsh Corgi (PWC) dogs with a homozygous mutation (c.118G>A) in the canine superoxide dismutase 1 (SOD1) gene were examined. The pathological features of the dogs were consistent with those of previous cases of DM in PWC. In the spinal lesions, diffuse SOD1 expression was observed in the neurons while no inclusion-like aggregates had formed, which disagreed with the findings of a previous study. A unique inducible nitric oxide synthase (iNOS) staining pattern in reactive astrocytes and a significant increase in ubiquitin immunoreactivity in the spinal lesions were also observed. These findings indicate the involvement of oxidative stress and the accumulation of ubiquitinated proteins in the pathogenesis of canine DM, whereas the role of SOD1 remains unclear.  相似文献   
95.
Phosphoinositide 3-kinases (PI3Ks) regulate fundamental cellular responses such as proliferation, apoptosis, cell motility, and adhesion. Viable gene-targeted mice lacking the p110 catalytic subunit of PI3Kgamma were generated. We show that PI3Kgamma controls thymocyte survival and activation of mature T cells but has no role in the development or function of B cells. PI3Kgamma-deficient neutrophils exhibited severe defects in migration and respiratory burst in response to heterotrimeric GTP-binding protein (G protein)-coupled receptor (GPCR) agonists and chemotactic agents. PI3Kgamma links GPCR stimulation to the formation of phosphatidylinositol 3,4,5-triphosphate and the activation of protein kinase B, ribosomal protein S6 kinase, and extracellular signal-regulated kinases 1 and 2. Thus, PI3Kgamma regulates thymocyte development, T cell activation, neutrophil migration, and the oxidative burst.  相似文献   
96.
本文研究了在内蒙古饲养管理条件下,降低牛奶含菌量的方法。共进行了5个方面的试验:头几把挤出的奶中细菌含菌量的检测;容器洗净对降低牛奶含菌量的作用;鲜奶过滤对奶中细菌含量的影响,冷水浴对降低牛奶含菌量的作用;盛奶罐口径大小及奶温高低对奶中细菌含菌量的影响。奶样抹片后,用纽曼染色液染色采用直接镜捡法进行细菌计数。结果表明:刚挤出的奶含有较多的细菌,随着挤奶的延续,奶中含菌量减少,彻底洗净挤奶器具和容器可大幅度降低牛奶的含菌量;用纱布过滤鲜奶并迅速冷却可明显降低牛奶的含菌量盛奶罐口径越大,牛奶中细菌含量越高。针对以上结果采取相应的对策,可降低牛奶中细菌的含量。  相似文献   
97.
In screening experiments for antiacne activity, methanolic and 50% ethanolic extracts of Caesalpinia sappan wood showed the most potent activity out of 28 species of plants extracts. These extracts showed inhibition of Propionibacterium acnes growth, lipase inhibitory activity, and antioxidant activity. In order to isolate the active compound from C. sappan, separation of the extract components was performed by column chromatography and preparative high-performance liquid chromatography (HPLC). Brazilin, protosappanin A, and sappanone B were isolated from methanolic extracts. Brazilin showed better antibacterial activity [minimum inhibitory concentration (MIC) = minimum bactericidal concentration (MBC) = 0.50 mg/ml] than protosappanin A (MIC = MBC = 1.00 mg/ml) and sappanone B (MIC = MBC > 2.00 mg/ml). The 50% inhibitory concentration (IC50) for lipase inhibition was lowest for brazilin (6 μM), which showed strong inhibition compared with protosappanin A (100 μM) and chloramphenicol (677 μM, positive control). The antioxidant activity of brazilin (IC50 8.8 μM) was not significantly different from protosappanin A (9.1 μM) and (+)-catechin (10.2 μM). The antioxidant activity of brazilin and protosappanin A were higher than sappanone B (IC50 14.5 μM). Brazilin is considered to have suffi ciently potent activity for use as an antiacne agent.  相似文献   
98.
In this paper, we examine the structure and change of the walleye pollock industry from a marketing and distribution perspective. Our focus is not only on industrial internationalisation, but also on local industry and community utilisation of walleye pollock. This is a subject of interest because its diverse utilisation has the potential to promote industrial management as well as the livelihood of local communities. We reason that Japan’s weakness in marketing, distribution and price setting of walleye pollock is largely due to its lack of competitiveness in the world market. Given the rapid decline of walleye pollock utilisation by local industry and society, it is of critical importance to take steps towards a long-term solution considering the rapid decline of walleye pollock use by our local industry and society. Our analysis indicates that Japan’s walleye pollock industry is inherently resilient, with diverse commodity chains, business flexibility and traditional food culture. However, as local industry and community have been reducing use of walleye pollock over time, there is a need to restore and reactivate the local society.  相似文献   
99.
Plant–fungal specificity between cucurbitaceous crops and Diaporthe sclerotioides, the causal agent of black root rot, was studied using cucumbers (Cucumis sativa), melons (Cucumis melo), pumpkins (Cucurbita maxima), watermelons (Citrullus lanatus) and bottlegourd (Lagenaria siceraria var. gourda). Twelve D. sclerotioides isolates from these cucurbit species were cross‐inoculated. The virulence of the isolates was evaluated as the area under the disease progress curve (AUDPC). All cucurbit species were susceptible to each isolate, but AUDPCs were significantly different among the hosts, with the order of greatest to least being melon, cucumber, watermelon, bottlegourd and finally, pumpkin. The infectiveness of isolates was assessed as the quantity of D. sclerotioides DNA detected in the hypocotyls of seedlings 2 weeks after inoculation using a real‐time PCR protocol. The fungal DNA quantities varied among the species in the same order as the AUDPCs. Whilst there were statistically significant correlations between the virulence and infectiveness of D. sclerotioides isolates in cucumbers, melons and bottlegourds, their coefficients of determination were not high (r2 < 0·6). Orthogonal contrasts indicated no specificity in either the fungal virulence or infectiveness between D. sclerotioides isolates and the cucurbit hosts from which these isolates originated. Thus, although the degree of host susceptibility to D. sclerotioides varies among cucurbit species, the absence of specificity to the host species in either virulence or infectiveness suggests the pathogen may spread via various cucurbit crops, irrespective of their original host species.  相似文献   
100.
Olive knot disease in Japan was first reported in Shizuoka Prefecture in 2014, and the causal agent was identified as Pseudomonas savastanoi pv. savastanoi. Subsequently, olive trees having knots were also found in Aichi and Kanagawa Prefectures in 2015, and the isolates from knots were also suspected to be P. savastanoi pv. savastanoi through preliminary examinations. Therefore, the Aichi and Kanagawa isolates were identified through comparison of isolates from three prefectures. Phylogenic analysis based on 16S rDNA and housekeeping genes (gyrB, rpoD, gltA and gap1) revealed that the isolates belonged to the same cluster as the pathotype strain, ICMP4352PT. The iaaM, H and L genes, which are involved in promotion of symptoms, and the ina gene coding the ice nucleation protein, were detected by PCR from all the isolates. In rep-PCR (ERIC and REP) analyses, the isolates yielded DNA fragment-banding patterns that were nearly identical to that of ICMP4352PT, but slight variations in banding patterns were observed among them. In a pathogenicity test, the isolates formed distinct knots on olive and pink jasmine. Phenotypic properties of the isolates were almost identical to those of ICMP4352PT, with the exception of d-sorbitol utilization. Consequently, Aichi and Kanagawa isolates from olive were identified as P. savastanoi pv. savastanoi, and several genetic diversities in terms of rep-PCR were found in the Japanese population of P. savastanoi pv. savastanoi, indicating their heterogeneity.  相似文献   
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