全文获取类型
收费全文 | 1417篇 |
免费 | 49篇 |
专业分类
林业 | 110篇 |
农学 | 66篇 |
296篇 | |
综合类 | 57篇 |
农作物 | 58篇 |
水产渔业 | 191篇 |
畜牧兽医 | 575篇 |
园艺 | 9篇 |
植物保护 | 104篇 |
出版年
2023年 | 8篇 |
2022年 | 25篇 |
2021年 | 22篇 |
2020年 | 20篇 |
2019年 | 21篇 |
2018年 | 27篇 |
2017年 | 38篇 |
2016年 | 38篇 |
2015年 | 46篇 |
2014年 | 46篇 |
2013年 | 140篇 |
2012年 | 71篇 |
2011年 | 91篇 |
2010年 | 40篇 |
2009年 | 35篇 |
2008年 | 82篇 |
2007年 | 98篇 |
2006年 | 82篇 |
2005年 | 88篇 |
2004年 | 53篇 |
2003年 | 47篇 |
2002年 | 55篇 |
2001年 | 52篇 |
2000年 | 33篇 |
1999年 | 31篇 |
1998年 | 20篇 |
1997年 | 5篇 |
1996年 | 12篇 |
1995年 | 6篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 14篇 |
1991年 | 12篇 |
1990年 | 9篇 |
1989年 | 14篇 |
1988年 | 10篇 |
1987年 | 5篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 4篇 |
1975年 | 5篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1969年 | 4篇 |
1968年 | 3篇 |
1967年 | 3篇 |
排序方式: 共有1466条查询结果,搜索用时 31 毫秒
981.
Based on histological structure and cellular formation, the endocrine pancreas (pars endocrina pancreatis) (PEP) or pancreatic islet (insulae pancreaticae), was divided into two types in the dog. One type of PEP was the islet of Langerhans. In the glandular lobule, the islet was surrounded by exocrine acini. The other type of PEP, in general, exhibited a feature of a neuro-insular complex. It was found within the interlobular connective tissue of the pancreas. This type of PEP was attached to a nerve bundle or ganglion. In the pancreas of the immature dog, a large population of endocrine cells was recognized to form a blood islet within the neuro-insular complex. 相似文献
982.
Chikara Kitajima Takeshi Watanabe Yasuo Tsukashima Shiro Fujita 《Journal of the World Aquaculture Society》1994,25(1):64-77
At many hatcheries in Japan, a high incidence of lordosis is being reported among marine physoclistous juveniles of red sea bream, Japanese sea bass, and amberjack. Extensive studies being conducted since 1975 to tackle this problem have led to the following conclusions, and effective countermeasures are being proposed.
During early larval development in the temporary physostomous stage, fish must be able to gulp air at the water surface for normal development of the swim bladder. The juveniles that fail to gulp air swim upward in an oblique position because of insufficient buoyancy, causing the backbone to curve in a V-shape.
The managerial solutions proposed are: 1) reduce the strong water current caused by vigorous aeration; 2) provide nutrient-enriched rotifers to produce healthy swimming larvae; and 3) prevent any oily film formation on the water surface. 相似文献
During early larval development in the temporary physostomous stage, fish must be able to gulp air at the water surface for normal development of the swim bladder. The juveniles that fail to gulp air swim upward in an oblique position because of insufficient buoyancy, causing the backbone to curve in a V-shape.
The managerial solutions proposed are: 1) reduce the strong water current caused by vigorous aeration; 2) provide nutrient-enriched rotifers to produce healthy swimming larvae; and 3) prevent any oily film formation on the water surface. 相似文献
983.
984.
985.
986.
987.
988.
Mochizuki H Takahashi M Nishigaki K Ide T Goto-Koshino Y Watanabe S Sato H Sato M Kotera Y Fujino Y Ohno K Uchida K Tsujimoto H 《Veterinary immunology and immunopathology》2011,141(3-4):307-311
There is significant lack of basic hematologic and immunological data in adult sows. Therefore, aim of this study was to provide respective reference intervals. 32 clinically healthy multiparous Large White sows aged 33.5 ± 9.6 months and all of them two months postpartum were included in this study. Mean erythrocyte count was 5.5 ± 0.7 × 10(6)/μl and total leukocyte count was 12.1 ± 2.1 × 10(3)/μl. Proportion of lymphocytes was 44.7 ± 10.2% and of neutrophils 41.6 ± 11.0%. The ratio of na?ve T helper (Th) cells to memory Th cells was 1:3.1 and the ratio of Th cells to cytotoxic T cells (CTLs) was 1:4.2. Proportions of regulatory T cells, NK cells, and CD21(+) B cells were lower (3.1, 2.6, and 6.0%) than those of memory Th cells ranging from 8.8 to 27.5% depending on the activation status and CTLs with 37.3%. γδ T cells were found at comparably high numbers (19.1%). Flow cytometric measurement of intracellular cytokines in PBMCs revealed marginal levels for IL-1β, IL-2, IL-4, IL-6, IL-10, and IL-12p35, but remarkable levels for TNF-α and IFN-γ. Highest mRNA levels were found for IL-1, IL-10, and TNF-α, with TNF-α showing the least inter-individual variation. 相似文献
989.
Clara RO Soares TS Torquato RJ Lima CA Watanabe RO Barros NM Carmona AK Masuda A Vaz IS Tanaka AS 《Veterinary parasitology》2011,181(2-4):291-300
The tick Rhipicephalus (Boophilus) microplus is one of the most important bovine ectoparasites, a disease vector responsible for losses in meat and milk productions. A cysteine protease similar to cathepsin L, named BmCL1, was previously identified in R. microplus gut, suggesting a role of the enzyme in meal digestion. In this work, BmCL1 was successfully expressed in Pichia pastoris system, yielding 54.8 mg/L of culture and its activity was analyzed by synthetic substrates and against a R. microplus cysteine protease inhibitor, Bmcystatin. After rBmCl1 biochemical characterization it was used in a selection of a peptide phage library to determine rBmCL1 substrate preference. Obtained sequenced clones showed that rBmCL1 has preference for Leu or Arg at P(1) position. The preference for Leu at position P(1) and the activation of BmCL1 after a Leu amino acid residue suggest possible self activation. 相似文献
990.
Obara H Fujihara M Watanabe Y Ono HK Harasawa R 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(6):841-843
We examined for 'Candidatus Mycoplasma haemominutum' infection in 167 blood samples collected from domestic dogs between 2008 and 2009 in the Tohoku area, Japan, and found 5 (3.0%) were positive by PCR assay. This is the first demonstration of 'Candidatus Mycoplasma haemominutum', a feline haemotropic mycoplasma, in the dogs raised in Japan. 相似文献