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41.
Kametani Y Ohshima S Kita YF Shimada S Kamiguchi H Shiina T Inoko H Kulski JK Ando A 《Veterinary immunology and immunopathology》2012,148(3-4):252-259
The expression of the major histocompatibility complex (MHC) classical class I genes is important for the adaptive immune response to target virus-infected cells and cancer cells. The up-regulation of the MHC is achieved by hormonal/cytokine signals including IFN-γ-inducible elements. The swine leukocyte antigen (SLA), the MHC class I region of pigs, consists of the duplicated classical class I genes, SLA-1, SLA-2 and SLA-3, but the molecular mechanisms involved in their up-regulation after T cell stimulation have not been fully elucidated. In order to better understand some of the putative regulatory mechanisms of SLA class I gene expression in activated T cells, we examined the coordinated expression of the SLA classical class I, IFN-γ and interferon regulatory factor-1 (IRF-1) genes in the peripheral blood mononuclear cells (PBMCs) of SLA homozygous Clawn miniature swine stimulated for 72h with either IFN-γ or an enterotoxin produced by Staphylococcus aureus. This enterotoxin, toxic shock syndrome-1 (TSST-1), is known to act as a superantigen (sAG) to activate the T cells in various vertebrate species. We showed by using mAbs and flow cytometry that the CD4(+)CD25(+) cell number of swine PBMCs was also increased by TSST-1 and to a lesser degree by IFN-γ. Time course analyses of the expression of the IFN-γ, IRF-1 and the three classical class I genes, SLA-1, SLA-2, and SLA-3, in PBMCs by quantitative real-time PCR revealed a transitory response to TSST-1 or IFN-γ stimulation. The IFN-γ mRNA levels in the PBMCs were continuously up-regulated over the first 48h by TSST-1 or IFN-γ. In contrast, SLA class I expression moderately increased at 24h and then decreased to a baseline level or less at 72h of IFN-γ or TSST-1 stimulation. The three classical SLA class I genes showed similar expression kinetics, although SLA-3 mRNA level was consistently lower than those of SLA-1 and -2. The expression of IRF-1, a modulator of SLA expression, showed similar kinetics to those of the three classical SLA class I genes. The expression profiles detected by flow cytometry of the SLA molecules on the cell surface of PBMCs were maintained at a consistently high level during cell stimulation with either TSST-1 or IFN-γ, which was distinct from the kinetics of mRNA expression. These results showed that miniature swine SLA class I mRNA expression was effectively and equally up-regulated among the three loci and coordinately with IRF-1 gene expression after stimulation of T cell activation by sAG or IFN-γ. 相似文献
42.
Fumie MAGATA Yoshikazu ISHIDA Akio MIYAMOTO Hidefumi FURUOKA Hisashi INOKUMA Takashi SHIMIZU 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):81-84
We investigated the
concentration of the bacterial endotoxin lipopolysaccharide (LPS) in the blood, ovarian
follicular fluid and uterine fluid of a clinical case of bovine metritis. A 2-year-old
lactating Holstein cow exhibited continuous fever >39.5°C for more than 2 weeks after
normal calving. The cow produced a fetid, watery, red-brown uterine discharge from the
vagina and was diagnosed with metritis. The LPS concentrations in plasma and uterine fluid
were 0.94 and 6.34 endotoxin units (EU)/ml, respectively. One of seven
follicles showed an extremely high level of LPS (12.40 EU/ml) compared to
the other follicles (0.62–0.97 EU/ml). These results might suggest the
presence of high concentration of LPS in follicles in cows with postpartum metritis. 相似文献
43.
Tsujimura K Oyama T Katayama Y Muranaka M Bannai H Nemoto M Yamanaka T Kondo T Kato M Matsumura T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(12):1663-1667
A single non-synonymous nucleotide substitution of guanine (G) for adenine (A) at position 2254 in the viral DNA polymerase gene (encoded by open reading frame [ORF] 30) of equine herpesvirus type 1 (EHV-1) has been significantly associated with neuropathogenic potential in strains of this virus. To estimate the prevalence of EHV-1 strains with the neuropathogenic genotype (ORF30 G(2254)) in the Hidaka district--a major horse breeding area in Japan--we analyzed the ORF30 genomic region in cases of EHV-1 infection in this area during the years 2001-2010. Of the 113 cases analyzed, 3 (2.7%) were induced by ORF30 G(2254) strains. This prevalence is lower than those observed in the U.S.A. (10.8-19.4%), Argentina (7.4%), France (24%), and Germany (10.6%). 相似文献
44.
Hiraoka H Hisasue M Nagashima N Miyama T Tanimoto T Watanabe M Itamoto K Mizuno T Inokuma H Okuda M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(6):665-668
An eleven-year-old female pug was referred to Yamaguchi University Animal Hospital for evaluation of anemia and thrombocytopenia. The cytological examination of the peripheral blood showed some giant monocytic lineage blast cells. A few granulocytes and platelets had dysplastic features. On day 7, in addition to increasing the monocytic lineage cells, the dysplastic features of the blood had also increased compared to the initial examination. We performed bone marrow aspiration upon her death. The bone marrow revealed dysplastic features in all three hematopoietic cell lines, and an increase in the monocytic cell line. Based on the features of the bone marrow and the peripheral blood, this case was confirmed to be myelodysplastic syndrome--Chronic myelomonocytic leukaemia (MDS-CMML). 相似文献
45.
Health status and productive performance of somatic cell cloned cattle and their offspring produced in Japan 总被引:1,自引:0,他引:1
Since the first somatic cell cloned calves were born in Japan in 1998, more than 500 cloned cattle have been produced by somatic cell nuclear transfer and many studies concerning cloned cattle and their offspring have been conducted in this country. However, most of the results have been published in Japanese; thus, the data produced in this country is not well utilized by researchers throughout the world. This article reviews the 65 reports produced by Japanese researchers (62 written in Japanese and 3 written in English), which employed 171 clones and 32 offspring, and categorizes them according to the following 7 categories: (1) genetic similarities and muzzle prints, (2) hematology and clinical chemistry findings, (3) pathology, (4) growth performance, (5) reproductive performance, (6) meat production performance and (7) milk production performance. No remarkable differences in health status or reproductive performance were found among conventionally bred cattle, somatic cell cloned cattle surviving to adulthood and offspring of somatic cell cloned cattle. Similarities in growth performance and meat quality were observed between nuclear donor cattle and their clones. The growth curves of the offspring resembled those of their full siblings. 相似文献
46.
47.
Thyroid hormone augments GLUT4 expression and insulin-sensitive glucose transport system in differentiating rat brown adipocytes in culture 总被引:1,自引:0,他引:1
Shimizu Y Shimazu T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(8):677-681
The effects of triiodothyronine (T3) on differentiation-dependent expression of GLUT and responses of glucose transport to insulin and norepinephrine (NE) were investigated. Precursor cells of brown adipocytes isolated from the interscapular brown adipose tissue of newborn rats were cultured in the absence or presence of various concentrations of T3. Western bolt analysis revealed that treatment with T3 resulted in an increased expression of GLUT4, in a dose-dependent manner, whereas GLUT1 contents were unchanged. In parallel with the increase in GLUT4 expression, T3 improved insulin sensitivity for glucose transport, being accompanied by an increase in maximal transport rate and a reduction of ED(50). In contrast, T3-treatment of the brown adipocytes during the differentiation process had little effect on NE-regulatable glucose transport system. These results suggest that T3 plays a predominant role in the development of insulin-sensitive glucose transport during differentiation of brown adipocytes. 相似文献
48.
Umehashi M Imamura T Akiyama S Kimachi K Tokiyoshi S Mikami T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(11):1017-1021
In order to confirm the in vivo effectiveness of anti- feline herpesvirus type 1 (FHV-1) mouse-cat chimeric antibody (FJH2), and anti-feline calicivirus (FCV) mouse-cat chimeric antibody (F1D7), cats that had been experimentally infected with FHV-1 or FCV were administered intravenously with the chimeric antibodies, and observed for clinical manifestations. The symptoms due to FHV-1 or FCV infection in the cats administered FJH2 or F1D7 were obviously decreased when compared with those of the non-administered control cats. From these results, it was confirmed that both FJH2 and F1D7 were effective at reducing the appearance of symptoms due to FHV-1 and FCV infection, respectively. 相似文献
49.
Takashi Nagai 《Journal of Pesticide Science》2021,46(4):366
Species sensitivity distributions (SSDs) of 38 pesticides with various modes of action were analyzed as a higher-tier ecological effect assessment based on collected acute toxicity data. Then the 5% hazardous concentrations (HC5) based on each SSD were calculated as the predicted no-effect concentrations for aquatic ecosystems. The differences between HC5 and registration criteria were small (within ten-fold) for 35 of the 38 pesticides. However, there were more than ten-fold differences for a fungicide and two herbicides. These results suggest that the current effect assessment scheme could underestimate the effect of such pesticides. This could be caused by differences in sensitivity of specific properties of the mode of action. 相似文献
50.
Yamamoto T Kobayashi S Nishiguchi A Nonaka T Tsutsui T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2006,68(2):137-142
Scattered SRM residues from BSE-infected cattle are possible to contaminate sewage during the slaughtering process in slaughterhouses. A proportion of the sludge discharged from wastewater treatment facilities at slaughterhouses has historically been processed into fertilizer. We therefore investigated the associated risk of BSE infection to cattle via sludge-derived fertilizer. Each stage of the process associated with BSE exposure was qualitatively evaluated and quantitative evaluations were subsequently performed using infectious dose as a unit of concern. Results of these qualitative evaluations indicated that installation of filter(s) at the drains to the wastewater treatment facilities has been undertaken by many slaughterhouses and has decreased the likelihood of SRM contamination of sewage. The level of sludge-derived fertilizer ingested by cattle was considered to be very low since the fertilizer is mixed with the ground soil, and the amount of soil ingested by cattle is likely to be small. Results from the quantitative analysis indicated the total infectious dose ingested by cattle in Japan from an infected cow has been estimated to be 5.5 x 10(-3) ID(50). Preventing scattering of SRM during the slaughtering process, installing filters to the drains with the removal of residues from the drain water and preventing the application of sludge-derived fertilizer to pasturelands would be effective to reduce the risk. Although the limited extent of available information, this study should provide useful indication for the development of an inclusive risk assessment for slaughterhouse sludge in the future. 相似文献