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61.
Adam AA Takahashi Y Katagiri S Nagano M 《The Japanese journal of veterinary research》2004,52(2):77-84
Effects of oxygen (O2) tension in the gas atmosphere during in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) on the efficiency of in vitro production of mouse embryos were examined. Mouse oocytes recovered from large antral follicles were subjected to IVM in Waymouth medium for 15, 16 and 17 hr under 5 or 20% O2 and then subjected to IVF and IVC under 5 or 20% O2 tension. Lowering the O2 tension in the gas atmosphere for IVM from 20 to 5% improved the cleavage rate after IVF when the oocytes were subjected to IVM for 15 hr; however, no improvement in the cleavage rate was observed when the culture period for IVM was extended to 16 and 17 hr. Lowering the O2 tension to 5% for IVM and IVC improved the development of the cleaved oocytes to the blastocyst stage, regardless of the culture period for IVM. However, the O2 tension for IVF had no remarkable effect on the subsequent embryonic development. These results demonstrate that 5% O2 is superior to 20% O2 for IVM and IVC, and suggest that 20% O2 for IVM may delay oocyte maturation and/or the acquisition of fertilizability and impair the developmental competence of oocytes. 相似文献
62.
Nagaya H Kanaya T Kaki H Tobita Y Takahashi M Takahashi H Yokomizo Y Inumaru S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(11):1395-1401
We developed a procedure for the large-scale purification of bovine interferon-tau (boIFN-tau) by means of a silkworm-baculovirus gene expression system. Recombinant boIFN-tau (rboIFN-tau) was efficiently produced in the silkworm infected with boIFN-tau cDNA recombinant baculovirus and accumulated in the haemolymph. To establish a purification method suitable for mass production, we tried three crude purification methods, namely, an acidification and neutralization treatment (ANT), silica gel column chromatography (SGCC), and Blue sepharose column chromatography (BSCC) with a combination of Q-sepharose (QSC) and chelating sepharose column chromatographies (CSCC). As a result, the acidification and neutralization treatment was found to be the most efficient and cost effective. With this combination, we obtained 91% pure products. To confirm the applicability of the procedure for mass production, we inoculated 100 silkworms with the recombinant virus, and recovered about 4.55 mg (1.26 x 10(8)U/mg) of 91% pure rboIFN-tau by means of a combination of the ANT, followed by QSC and CSCC. 相似文献
63.
Miyazawa K Aso H Honda M Kido T Minashima T Kanaya T Watanabe K Ohwada S Rose MT Yamaguchi T 《Research in veterinary science》2006,81(1):40-45
Dendritic cells (DCs) are professional antigen presenting cells, which initiate primary immune responses and also play an important role in the generation of peripheral tolerance. There is no reliable method established for the isolation of bovine peripheral blood DCs, and furthermore, the phenotypes and the functions of bovine DCs are still not fully clear. In the present study, we have attempted to identify bovine peripheral blood DCs by negative-selection. In bovine peripheral blood mononuclear cells (PBMC), we have newly characterized the phenotype of DCs, which is CD11c+/CD172a+. These cells display features of myeloid type DCs. In the thymic medulla, CD11c+/CD172a+ cells were also present and CD1+/CD172a+ cells were additionally detected as a population of DCs. The data suggest that one of the bovine DCs phenotypes from PBMC is derived from myeloid lineages lacking a CD1 molecule, which then drift to several tissues, and that they then may express a CD1 molecule upon their functional differentiation. 相似文献
64.
Ohmi A Tsukamoto A Ohno K Uchida K Nishimura R Fukushima K Takahashi M Nakashima K Fujino Y Tsujimoto H 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2012,74(1):59-64
Medical records of dogs with colorectal polyps were retrospectively reviewed, and clinical presentation of inflammatory colorectal polyps in miniature dachshunds was evaluated. Of 33 dogs found to have colorectal polyps, miniature dachshunds were markedly over-represented with 16 dogs (48%), of which 12 (75%) were found to have inflammatory polyps. Multiple polyps localized between the rectum and the descending colon was the most common finding in miniature dachshunds with inflammatory polyps. Twenty dogs (80%) out of 25 miniature dachshunds with inflammatory colorectal polyps responded to immunosuppressive therapy using prednisolone and cyclosporine. The results of this study indicate that miniature dachshunds are predisposed to develop inflammatory colorectal multiple polyps, for which immunosuppressive therapy may be a treatment option. 相似文献
65.
Himaki T Mizobe Y Tsuda K Suetomo M Yamakuchi H Miyoshi K Takao S Yoshida M 《The Journal of reproduction and development》2012,58(4):398-403
The objective of this study was to examine the effect of postactivation treatment with latrunculin A (LatA), an actin polymerization inhibitor, on in vitro and in vivo development of somatic cell nuclear transfer (SCNT) embryos derived from kidney fibroblasts of an aged Clawn miniature boar (12 years old). After electric activation, SCNT embryos were treated with 0, 0.5 or 1 μM LatA and cultured in vitro. The rate of blastocyst formation was significantly higher (P<0.05) in SCNT embryos treated with 0.5 μM LatA (38%) than those in control (14%). When cloned embryos treated with 0.5 μM LatA were transferred into the oviducts of two recipient miniature gilts to assess their development in vivo, both recipients became pregnant; one maintained pregnancy to term, and a live piglet (weighing 220 g) was delivered by Caesarean section. The results of this study indicated that the postactivation treatment with LatA was effective in improving in vitro developmental capacity of SCNT miniature pig embryos derived from kidney fibroblasts of an aged animal and that miniature pig cloned embryos treated with LatA had the ability to develop to term. 相似文献
66.
Over the past four decades, many researchers have applied the theory of island biogeography (IBT) to predict and understand species loss and distribution in fragmented landscapes. Recent studies found that specialist species were more affected by fragment size and isolation than generalists. However, the mechanisms underlying different effects of area and isolation among specialists and generalists are unknown. We tested the predictions of IBT on butterfly assemblages in Tokyo, Japan, and hypothesized that the effects of fragment size and isolation would be stronger for specialists than for generalists. We classified butterfly species into specialists and generalists for each of two dimensions (food range and voltinism) and according to tolerance to the matrix. We recorded 26 feeding specialists and 27 generalists, 24 seasonal specialists and 29 generalists, 32 low matrix-tolerant species and 21 high matrix-tolerant species in 20 forest fragments. We used generalized linear models to relate the number of species in a fragment to fragment size and isolation (distance to the mainland). The averaged models based on AICc showed that fragment size had positive and significant effects on both specialist and generalist and high matrix-tolerant butterfly species richness. However, the negative effects of isolation on species richness were only found in specialist and low matrix-tolerant species. Our results demonstrate that patch isolation only affects specialist species. This suggests that when applying IBT to terrestrial fragmented landscapes, researchers should be careful not to overlook patch area and isolation effects on specialists. 相似文献
67.
Hiroshi Ohta Kanae Takada Shidow Torisu Masashi Yuki Yu Tamura Nozomu Yokoyama Tatsuyuki Osuga Sue Yee Lim Masahiro Murakami Noboru Sasaki Kensuke Nakamura Masahiro Yamasaki Mitsuyoshi Takiguchi 《Veterinary immunology and immunopathology》2013
Inflammatory colorectal polyps (ICRPs) in miniature dachshunds are recently recognized as a major cause of large bowel diarrhea in this dog breed in Japan. ICRPs are characterized by the formation of multiple small polyps and a space-occupying large polyp in the colorectal area, and are thought to be a novel form of inflammatory bowel disease (IBD). In humans, specific cytokine patterns attributed to T helper (Th)1, Th17 and regulatory T cells have important roles in the pathogenesis of IBD. Thus, the aim of the present study was to assess the gene expression of cytokines of T cell subsets in the colorectal mucosa from dogs with ICRPs. Colorectal mucosal specimens from 10 dogs with ICRPs and 14 control dogs were used in this study. Interferon (IFN)-γ, interleukin (IL)-4, IL-17A and IL-10 mRNA expression was assessed using quantitative real-time PCR. IL-17A mRNA expression was significantly increased in large polyps compared to small polyps and controls. IFN-γ and IL-10 mRNA expression in large polyps were significantly higher than in controls. There was no significant difference in IL-4 mRNA expression among the three groups. IL-17A is thought to play important roles in the pathogenesis of ICRPs. IL-10 up-regulation could oppose the proinflammatory function of IL-17A. 相似文献
68.
Atsuko Murai Soichi Maruyama Masahiko Nagata Masashi Yuki 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2013,42(3):377-381
A 2‐year, 7‐month‐old female Chihuahua was admitted for a mammary mass measuring one cm in diameter. The dog had a history of demodicosis for 4 months and showed signs of pseudopregnancy at the time of the visit. Cytologic examination of an aspirate of the mass revealed a large number of macrophages containing nonstaining bacterial rods, which were acid‐fast in a Ziehl–Neelsen stain, suggesting mycobacterial infection. Histologic examination of the mass revealed a pyogranulomatous mastitis characterized by an infiltration with macrophages containing acid‐fast bacteria. Mycobacterium kansasii was subsequently cultured and identified by PCR. Surgical excision of the mass resulted in the growth of other dermal masses, but antimycobacterial treatment with rifampin and clarithromycin resolved these masses within 1 month. Three months after discontinuation of the treatment, similar organisms were found in aspirates of the enlarged bilateral inguinal lymph nodes by cytologic examination. Despite antimycobacterial treatment for another 4 months, there was no improvement and demodicosis also recurred. The dog eventually died of lymphoma 5 months after the relapse of mycobacterial infection. Although M kansasii is considered an important pathogen for pulmonary and cutaneous disease in people, there is only one report in a dog with an infection in a pleural effusion. As both adult‐onset demodicosis in dogs as well as mycobacterial infection in people have been associated with T‐lymphocyte deficiency, the M kansasii infection in this dog may have been associated with a condition of immune compromise. 相似文献
69.
Daisuke FUKUI Masashi NAGANO Ryohei NAKAMURA Gen BANDO Shinichi NAKATA Masao KOSUGE Hideyuki SAKAMOTO Motozumi MATSUI Yojiro YANAGAWA Yoshiyuki TAKAHASHI 《The Journal of reproduction and development》2013,59(5):491-495
Artificial insemination (AI) can help to avoid inbreeding and genetic degeneration
for sustaining genetically healthy populations of endangered species in captivity.
Collection of a sufficient quantity of viable sperm is an essential first step in the
AI process. In the present study, we examined the effects of frequent
electroejaculation on semen characteristics in a Siberian tiger. We collected semen
in all 17 trials during 6 breeding seasons (6 years). The mean number of sperm and
the percentage of motile sperm were 294.3 ± 250.2×106/ejaculate and 82.4 ±
11.4%, respectively. The number of motile sperm tended to increase during frequent
electroejaculation in the same breeding season. Semen collection by
electroejaculation can be performed effectively up to the fourth sequential
ejaculate, which contained the most sperm in the study. In conclusion, frequent
collection of sperm by electroejaculation from tigers may be effective for collection
of a large number of motile sperm. 相似文献
70.
Masashi?Hatamoto Takanori?Tanahashi Jun?Murase Kazuo?Matsuya Motoki?Hayashi Makoto?Kimura Susumu?AsakawaEmail author 《Biology and Fertility of Soils》2008,44(3):527-532
To estimate the succession and phylogenetic composition of the eukaryotic communities responsible for the decomposition of
rice straw compost under flooded conditions during the cultivation period of paddy rice, denaturing gradient gel electrophoresis
(DGGE) analysis targeting 18S rDNA followed by sequencing was conducted in a Japanese paddy field. The eukaryotic communities
in rice straw compost incorporated into the flooded paddy field were influenced by the mid-season drainage and mainly composed
of fungi (Ascomycota, Zygomycota, and Chytridiomycota) and protozoa (Ciliophora, Euglyphida, and Dactylopodida), most of which
existed continuously during the cultivation period of paddy rice. The results indicated that these eukaryotic members were
associated with the decomposition of rice straw compost in paddy field soil directly or indirectly. 相似文献