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排序方式: 共有390条查询结果,搜索用时 15 毫秒
111.
Sato Y Ohe K Fukuyama M Furuhata K Kishikawa S Sakai S Kiuchi A Hara M Watanabe T Ishikawa Y Taneno A 《The Veterinary record》2004,155(25):800-805
In June 1993, two of five pet cats kept in Yokohama city in Japan suddenly became agitated and died. Feline calicivirus (FCV) was isolated from them. One strain (FCV-S) was isolated from the spinal cord, lung and tonsil of cat 1, another (FCV-B) from the ileum, medulla oblongata and cervical spinal cord of cat 2, and a third (FCV-SAKURA) from the oral cavity of one of the three surviving cats which showed no clinical signs. These three strains were equally resistant to pH 3.0 and serologically similar to each other, but distinct from strain F9. A genetic analysis, using a 208 base pair fragment from region E of the capsid, showed that FCV-Ari had a 70.4 per cent nucleotide and 77.3 per cent amino acid homology and FCV-F9 had a 68.6 per cent nucleotide and 73.9 per cent amino acid homology with the three strains, indicating that these two strains were genetically distinct from the three new isolates. Unvaccinated cats and cats which had been vaccinated against FCV-F9 developed watery diarrhoea but did not become agitated after the administration of FCV-S. The FCV-S strain did not induce signs of excitability after it was administered orally to specific pathogen-free cats. 相似文献
112.
The previous scanning electron microscopy study of the Hypoderma species suggested that Hypoderma sinense Pleske (H. sinense) was different from Hypoderma bovis (H. bovis) and Hypoderma lineatum (H. lineatum). In this study, the mitochondrial cytochrome oxidase I (COI) gene sequence of H. sinense was compared with those of the other two species. The H. sinense sequence showed only 88.3% homology to H. bovis and 88.5% to H. lineatum. The results of the sequencing analysis confirm that H. sinense is a different species from H. bovis and H. lineatum. 相似文献
113.
Fukai K Onoda H Itou T Sato M Miura Y Sakai T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1413-1416
G8 bovine group A rotaviruses isolated in Japan were genetically and serologically characterized. The VP7 gene nucleotide and amino acid sequences revealed high identity with each other. All Japanese G8 strains were classified into the same lineage in the phylogenetic analysis based on VP7 gene sequences. Antisera to four Japanese G8 strains neutralized other G8 strains, but their neutralizing titers were between 8-fold lower and 2-fold higher than homologous strains. These results suggest that the VP7s of Japanese G8 strains have similar genetic and serologic characteristics. Observed differences in the neutralizing abilities of antisera for each strain appear to depend on differences in the P serotypes/genotypes. 相似文献
114.
Assessment of bovine X- and Y-bearing spermatozoa in fractions by discontinuous percoll gradients with rapid fluorescence in situ hybridization 总被引:1,自引:0,他引:1
Kobayashi J Oguro H Uchida H Kohsaka T Sasada H Sato E 《The Journal of reproduction and development》2004,50(4):463-469
This study was designed to apply the method of discontinuous Percoll gradients for sex preselection in bovine semen by using a current developed molecular technique, fluorescence in situ hybridization (FISH). In addition, we attempted to amplify the level of enrichment of X- or Y-bearing spermatozoa by treating for activating sperm motility performance with 10 mM caffeine. Bovine spermatozoa were fractionated on Percoll gradients into two major subpopulations of motile spermatozoa (bottom fraction) and weak motile spermatozoa (top fraction). The percentage of Y-bearing spermatozoa in the top fraction (52.9%) slightly exceeded and that in the bottom fraction (44.3%) decreased significantly (P<0.001) compared with the theoretical ratio (50:50). Washing sperm with BO medium affected a deviation between the two sex populations, whereas semen activated with caffeine showed no difference in the percentage of X- and Y-bearing spermatozoa in both fractions compared with the theoretical ratio (50:50). These results show that the proportion of X- and Y-bearing bovine spermatozoa can deviate after discontinuous Percoll gradients, although the proportion of X- and Y-bearing bovine spermatozoa was affected by sperm motility of the sample applied. 相似文献
115.
Yu FURUSAWA Masashi TAKAHASHI Mariko SHIMA-SAWA Hitoshi HATAI Noriaki MIYOSHI Osamu YAMATO Akira YABUKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(9):1363
Epithelial–mesenchymal transition (EMT) plays a crucial role in metastasis of epithelial tumors; however, it is challenging to detect EMT by cytology. In the present study, EMT was visualized by fluorescence-immunocytochemistry (FICC). Air-dried smears from epithelial tumors of dogs (n=22) and cats (n=9) were stained using mouse monoclonal anti-E-cadherin and rabbit monoclonal anti‐vimentin antibodies. Enzymatic immunohistochemistry (IHC) revealed that 51.6% (8/22 in dogs, 8/9 in cats) of the cases showed EMT. In dogs, FICC could detect EMT in 62.5% (5/8) of those cases. In cats, FICC could detect EMT in 100% (8/8) of the cases. In conclusion, the present FICC method could successfully detect EMT using conventional air-dried cytology smear slides. 相似文献
116.
Naoki Negishi Katsuhiko Nakahama Nobuaki Urata Mikiko Kojima Hitoshi Sakakibara Akiyoshi Kawaoka 《New Forests》2014,45(4):577-587
Eucalyptus globulus is the one of the most economically important trees for pulp and paper industries due to its fast growth and short harvesting cycle. However, E. globulus is well known as a woody plant that is hard to propagate vegetatively. In this study, we found wide distribution of rooting ability among seven independent genotypes we tested. Analysis of the mechanism of adventitious rooting by using the auxin transport inhibitor, N-naphthylphthalamic acid, revealed that polar auxin transport is crucial in root formation. The gravitropism of the stem was highly correlated to the percentage of adventitious root formation. Hormonal analysis showed that the levels of indole-3-acetic acid (IAA) were the same between difficult-to-root and easy-to-root genotypes, whereas levels of IAAsp (indole-3-acetyl aspartic acid) were higher in the difficult-to-root genotype, indicating that IAA metabolism might play an important role in adventitious root formation in this species. Levels of several cytokinins exhibited differences between genotypes that varied in their cutting performance and rooting ability. Furthermore, higher level of cytokinin in elongating shoots were correlated with rooting percentage. Taken together, our results indicate that both auxins and cytokinins play a role in adventitious root formation in E. globulus, and that a complex interplay between the levels of auxins and cytokinins and their metabolism might result in root formation in this commercially important plant. 相似文献
117.
Negative feedback regulation ensures the one receptor-one olfactory neuron rule in mouse 总被引:1,自引:0,他引:1
Serizawa S Miyamichi K Nakatani H Suzuki M Saito M Yoshihara Y Sakano H 《Science (New York, N.Y.)》2003,302(5653):2088-2094
In the mouse olfactory system, each olfactory sensory neuron (OSN) expresses only one odorant receptor (OR) gene in a monoallelic and mutually exclusive manner. Such expression forms the genetic basis for OR-instructed axonal projection of OSNs to the olfactory bulb of the brain during development. Here, we identify an upstream cis-acting DNA region that activates the OR gene cluster in mouse and allows the expression of only one OR gene within the cluster. Deletion of the coding region of the expressed OR gene or a naturally occurring frame-shift mutation allows a second OR gene to be expressed. We propose that stochastic activation of only one OR gene within the cluster and negative feedback regulation by that OR gene product are necessary to ensure the one receptor-one neuron rule. 相似文献
118.
Harada Y Takagaki Y Sunagawa M Saito T Yamada L Taniguchi H Shoguchi E Sawada H 《Science (New York, N.Y.)》2008,320(5875):548-550
Hermaphroditic organisms avoid inbreeding by a system of self-incompatibility (SI). A primitive chordate (ascidian) Ciona intestinalis is an example of such an organism, but the molecular mechanism underlying its SI system is not known. Here, we show that the SI system is governed by two gene loci that act cooperatively. Each locus contains a tightly linked pair of polycystin 1-related receptor (s-Themis) and fibrinogen-like ligand (v-Themis) genes, the latter of which is located in the first intron of s-Themis but transcribed in the opposite direction. These genes may encode male- and female-side self-recognition molecules. The SI system of C. intestinalis has a similar framework to that of flowering plants but utilizing different molecules. 相似文献
119.
Critical roles of activation-induced cytidine deaminase in the homeostasis of gut flora 总被引:1,自引:0,他引:1
Fagarasan S Muramatsu M Suzuki K Nagaoka H Hiai H Honjo T 《Science (New York, N.Y.)》2002,298(5597):1424-1427
Activation-induced cytidine deaminase (AID) plays an essential role in class switch recombination (CSR) and somatic hypermutation (SHM) of immunoglobulin genes. We report here that deficiency in AID results in the development of hyperplasia of isolated lymphoid follicles (ILFs) associated with a 100-fold expansion of anaerobic flora in the small intestine. Reduction of bacterial flora by antibiotic treatment of AID-/- mice abolished ILF hyperplasia as well as the germinal center enlargement seen in secondary lymphoid tissues. Because an inability to switch to immunoglobulin A on its own does not lead to a similar phenotype, these results suggest that SHM of ILF B cells plays a critical role in regulating intestinal microflora. 相似文献
120.
Hitoshi Hatai Takashi Hatazoe Haruka Seo Teruaki Tozaki Shingo Ishikawa Noriaki Miyoshi Kazuhiro Misumi Seiji Hobo 《Journal of veterinary diagnostic investigation》2021,33(2):379
A 27-y-old Anglo-Arabian gelding with bay coat color was presented with a swelling of the left maxillary region. Fenestration on the left maxilla revealed that the left maxillary sinus was filled with black-red tissue. A portion of the tissue was excised and diagnosed histologically as malignant melanoma. Genotyping of the STX17 gene for gray coat color revealed that the horse did not have the “gray” factor. The horse was euthanized ~3 mo after first presentation. During autopsy, a black-to-gray mass extended from the left nasal cavity to the surrounding paranasal sinus and invaded the hard palate, cribriform plate, and the cranial portion of the left olfactory bulb. Moreover, identical black nodules were present in lymph nodes from the mandible to the larynx, and in the spleen, liver, kidney, and adrenal glands. However, masses were not found in the skin, perineal region, or pelvic cavity. All of the black-to-gray nodules were malignant melanomas that were histologically identical to the initial biopsy; tumor emboli were also found in the kidney. Sinonasal mucosal melanoma is a rare disease in horses. 相似文献