全文获取类型
收费全文 | 924篇 |
免费 | 45篇 |
国内免费 | 1篇 |
专业分类
林业 | 90篇 |
农学 | 26篇 |
132篇 | |
综合类 | 27篇 |
农作物 | 44篇 |
水产渔业 | 157篇 |
畜牧兽医 | 418篇 |
园艺 | 7篇 |
植物保护 | 69篇 |
出版年
2023年 | 2篇 |
2022年 | 26篇 |
2021年 | 43篇 |
2020年 | 25篇 |
2019年 | 15篇 |
2018年 | 23篇 |
2017年 | 23篇 |
2016年 | 40篇 |
2015年 | 33篇 |
2014年 | 58篇 |
2013年 | 72篇 |
2012年 | 56篇 |
2011年 | 56篇 |
2010年 | 30篇 |
2009年 | 35篇 |
2008年 | 65篇 |
2007年 | 67篇 |
2006年 | 69篇 |
2005年 | 53篇 |
2004年 | 47篇 |
2003年 | 28篇 |
2002年 | 40篇 |
2001年 | 28篇 |
2000年 | 16篇 |
1999年 | 4篇 |
1998年 | 9篇 |
1995年 | 3篇 |
1989年 | 1篇 |
1985年 | 2篇 |
1975年 | 1篇 |
排序方式: 共有970条查询结果,搜索用时 31 毫秒
911.
Shimoda K Kimura J Oguri S Nakamura N Urano T Maejima K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2002,64(12):1133-1135
A total of 713 strains of fecal Escherichia coli (E. coli) isolated from laboratory animals in the colonies of 4 research laboratories and 4 commercial breeders in Japan in 1994 were examined in regard to resistance to 8 antibacterial agents. The incidence of resistance to sulfadimethoxine (Su), streptomycin (Sm), ampicillin, cephaloridine, tetracycline, chloramphenicol, kanamycin, and gentamicin was 99.9%, 32.5%, 6.7%, 0.7%, 7.0%, 2.6%, 6.6% and 0.7%, respectively. These results indicated that Su and Sm resistance are penetrating into normal E. coli strains isolated from laboratory animals. 相似文献
912.
Satoshi Katayama 《Fisheries Science》2001,67(3):401-407
SUMMARY: The objective of this study was to reveal the spawning grounds and reproductive characteristics of anadromous and resident pond smelt, Hypomesus nipponensis , coexisting in Lake Ogawara. Life history styles of females shedding in spawning grounds in the lake and its inflowing rivers were differentiated by otolith increment analysis. Size, dry weight, and water content of mature oocytes and fecundity of fish were compared between resident and anadromous fish. Both anadromous and resident fish spawned in the lake. In contrast, no resident fish were found in any of the inflowing rivers, where only anadromous fish spawned. Regression of fecundity against standard length was discontinuous with an inflection point at 63.8 mm, which is the body size that differentiates large anadromous spawning groups from small resident spawning groups. Mean oocyte diameters were not significantly different between resident and anadromous fish. The eggs of resident fish had significantly more water content and a significantly lower dry weight than those of anadromous fish. These differences might influence the growth and developmental processes of progeny. 相似文献
913.
Ricardo Perez-Enriquez Masaki Takemura Kazuo Tabata Nobuhiko Taniguchi 《Fisheries Science》2001,67(1):71-78
SUMMARY: Stock enhancement is used in Japan as a tool to help the replenishment of wild populations of red sea bream Pagrus major . In this study, we analyzed the genetic diversity and composition of wild red sea bream at seven locations around Shikoku Island, South-west Japan, using three microsatellite loci. This analysis was done to test the hypothesis that: (i) red sea bream comprises a single Mendelian population along Japan; and (ii) stock enhancement programs around Shikoku Island are causing genetic differentiation among wild stocks. The results indicated that some locations from the Shikoku area were not significantly different from the rest of Japan, supporting the hypothesis of a single Mendelian population. Significant departures from Hardy–Weinberg equilibrium and significant pairwise FST among locations indicated genetic instability within this region. We suggest that the stock enhancement programs made in the region are the possible cause of this genetic instability. A management scheme for the hatcheries involved in the stock enhancement of red sea bream is presented. 相似文献
914.
Bo-Song Ryang Tadashi Matsumoto Takashi Kobori Yoshitaka Kosaka Satoshi T. Ohki 《Journal of General Plant Pathology》2005,71(4):308-313
Cucumber cotyledons inoculated with Cucumber mosaic virus (CMV, Pepo strain) or Zucchini yellow mosaic virus (ZYMV, Z5-1 isolate) developed either mild chlorotic spots or no symptoms. Cotyledons treated with CMV plus ZYMV also developed mild chlorotic spots. However, plants ZYMV-inoculated cotyledons had veinal yellowing and gradual cell death by 20 days postinoculation (dpi) when co-inoculated with CMV on the other cotyledon. When analyzing this synergism, an enzyme-linked immunosorbent assay showed that CMV gradually increased in CMV-inoculated cotyledons of plants, with the other cotyledon mock- or ZYMV-inoculated. However, CMV significantly increased at 9 to 14 dpi in the ZYMV-inoculated cotyledons of plants co-infected with CMV. ZYMV similarly increased in cotyledon pairs of both co-infected and singly infected plants. Inoculation with PepoΔ2b, a modified Pepo-CMV that lacks translation of the 2b protein, revealed that PepoΔ2b without the 2b protein systemically infected cucumber but induced no symptoms on cotyledons or true leaves. Plants with a ZYMV-inoculated cotyledon and co-infected with PepoΔ2b did not undergo cell death; nevertheless, PepoΔ2b was at high levels comparable to levels of CMV in the ZYMV-inoculated cotyledon. The 2b protein thus seems essential for induction of the novel gradual cell death in ZYMV-inoculated cotyledons of cucumbers co-infected with CMV. 相似文献
915.
We previously reported that a strain of Cucumber mosaic virus (Pepo CMV) invaded the shoot apical meristem (SAM, tunica corpus) of tobacco plants at 6–8 days postinoculation (dpi), contrary to earlier observations. To identify a viral factor determining the ability to invade the SAM, we inoculated plants with two other CMV strains, MY17 and Y, and tested the three strains in this study. Immunohistochemical microscopy revealed that MY17 CMV invaded the SAM at 7 dpi, the same as Pepo CMV, but Y CMV did not, even at 21 dpi. Using RNA pseudorecombinants between Pepo and Y CMV, we found that Pepo RNA 2 affected the rate of SAM invasion, and Pepo RNA 3 was required for successful SAM invasion. Inoculation with RNA 1 and RNA 2 from Y CMV and RNA 3 containing the chimeric coat protein (CP) gene between Pepo and Y CMV or a Y RNA 3 point mutant containing a Ser-to-Pro substitution at position 129 in CP (Y129P) revealed that amino acid 129 of CP is the determinant for successful SAM invasion. The rate of SAM invasion of the pseudorecombinants and Y129P was consistent with the efficiency of cell-to-cell movement in the inoculated leaves, implying that SAM invasion by CMV strains may be due to efficient cell-to-cell movement. 相似文献
916.
Tsuyoshi SHIMMURA Satoshi HIRAHARA Yusuke EGUCHI Katsuji UETAKE Toshio TANAKA 《Animal Science Journal》2007,78(3):314-322
The aim of the present study was to compare old layers' level of welfare and performance between conventional and large furnished cages under hot environmental conditions. At the age of 80 weeks, 104 Boris Brown layers were divided into two groups: 12 conventional cages (two hens/cage) and four large furnished cages (20 hens/cage, 240 cm wide × 62 cm deep). The room temperature was set to fluctuate between 25 and 33°C in a day. The hens' behavior, immune response, performance and physical condition were measured. Aggression and moving were more frequent in furnished than in conventional cages (P < 0.05 for both items). Egg production (P < 0.05), egg mass (P < 0.05) and feed conversion ratio (P < 0.01) were better in conventional cages than in furnished cages. No significant differences were found in the birds' immune responses or physical condition between the cage designs. In conclusion, under a hot environment, the performance of old layers in large furnished cages was lower compared with that in small conventional cages, which might be due to their greater aggressive interactions. However, it was not evident that welfare level was lower in large furnished cages compared with conventional cages. Hereafter, additional studies about large furnished cages using young layers over a long term should be performed. 相似文献
917.
Iwamoto H Tabata S Kakakibara K Nishimura S Gotoh T Koga Y 《British poultry science》2001,42(3):321-326
1. The collagen architecture of M. iliotibialis lateralis in chicken was observed under the scanning electron microscope after muscle maceration in NaOH. 2. Immunohistochemical methods showed Type I and III collagens to be distributed over both perimysium and endomysium. 3. Thick perimysium around secondary myofibre fasciculi was composed of many large longitudinal collagen bundles and a few small circumferential bundles. In contrast, thin perimysium around primary myofibre fasciculi showed mainly circumferential bundles. 4. Endomysium had a honeycomb-like structure and consisted of a fine collagen mesh, its main fibre striation being circumferential. 5. It is suggested that functional demand differs between thick perimysium and thin endomysium. 相似文献
918.
Tsuchiya R Tatsuki Y Kitao S Furuichi M Neo S Hisasue M Yamada T Kobayashi K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(2):181-183
Characteristics of the signal transduction in Platelet activating factor (PAF)-activated platelets and effects of anti-platelet agents on this response were investigated in vitro for potential therapeutic applications in canine endotoxemia. Blockade of the PAF receptor by a specific blocker has the strongest inhibitive effect on the PAF-induced platelet reactions. The response was also inhibited by either Ca(2+) channel blockers or prostaglandin E(1). 相似文献
919.
Avian haemosporidian parasites infection in wild birds inhabiting Minami-daito Island of the Northwest Pacific, Japan 总被引:1,自引:0,他引:1
Murata K Nii R Yui S Sasaki E Ishikawa S Sato Y Matsui S Horie S Akatani K Takagi M Sawabe K Tsuda Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(5):501-503
Haemosporidian parasites infection among wild birds inhabiting Minami-daito Island was studied. Blood films from 183 birds representing 4 species of 4 families were examined microscopically. Avian haemosporidian parasites were detected in 3 species with an overall prevalence of 59.6%. None of the 30 Daito scops owls (Otus scops interpositus) examined were infected. Either Haemoproteus sp. or Plasmodium sp. infection was found in 14 of 31 (45.2%) Borodino islands white-eyes (Zosterops japonicus daitoensis). Plasmodium spp. were found in 94 of 102 (92.2%) bull-headed shrikes (Lanius bucephalus) and 1 of 20 (5%) tree sparrows (Passer montanus). 相似文献
920.
Hoshino Y Takagi S Osaki T Okumura M Fujinaga T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(6):581-588
We attempted to accumulate the basic data for evaluation of activated lymphocyte therapy for small animal medicine. The peripheral blood mononuclear cells (PBMCs) collected from healthy dogs were activated using anti-CD3 antibody and human recombinant (hr) interleukin (IL)-2 and reactivated using hr interferon (IFN)-alpha and hr IL-2. The property of obtained cells was compared with PBMCs. The number of cells was shown to have increased approximately>50 -fold by cultivation. The proportion of CD8+ cells was significantly increased, the cytotoxicity of the cultured cells was revealed to have been reinforced. Additionally, CD56 mRNA levels tended to have increased. The cells obtained by this method were confirmed to be activated lymphocytes. Furthermore, we investigated the effects of sequential administration of the obtained cells to healthy dogs. By sequential administration of the activated lymphocytes, the cell proliferative activity, proportion of CD4+ cells and CD8+ cells, and serum IFN-gamma concentration were shown to have increased, and no severe adverse effects were observed. Consequently, activated lymphocytes could be induced using anti-CD3 antibody and IL-2 in healthy dogs, and sequential administration of activated lymphocytes reinforced the recipient's immunity. 相似文献