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41.
Iridovirus infections in farm-reared tropical ornamental fish 总被引:2,自引:0,他引:2
A systemic viral infection in both gourami Trichogaster spp. and swordtail Xiphophorus hellerii and an outbreak of lymphocystis in scalare Pterophyllum scalarae and gourami are reported to have occurred in fish reared in ornamental fish farms in Israel. The systemic infection developed in endothelial cells that became hypertrophic and their contents were modified. The presence of such cells in light-microscopically examined stained smears and sections provides an initial indication for this systemic viral infection. Infection in gourami caused hemorrhagic dropsy. Transmission electron microscopic (TEM) images of iridovirus-like particles recovered from gouramies showed them to be 138 to 201 nm from vertex to vertex (v-v); those from swordtails were 170 to 188 nm v-v. TEM images of lymphocystis virions from scalare were 312 to 342 nm v-v and from gourami 292 to 341 nm v-v. Lymphocystis cells from the gourami were joined by a solid hyaline plate, which was lacking in the infection in scalare where the intercellular spaces between the lymphocystis cells consisted of loose connective tissue. 相似文献
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Supplementation of IVM medium with cysteamine, beta-mercaptoethanol, cysteine and cystine induced bovine oocyte glutathione (GSH) synthesis, but only the effect of cysteamine on the developmental competence of these oocytes was tested. During IVM of sheep oocytes, cysteamine but not beta-mercaptoethanol increased embryo development. However, it is not known how long the high intracellular oocyte GSH levels obtained after IVM with thiol compounds, can be maintained. Thus, the present study was carried out to evaluate the effects of supplementing maturation medium with 100 microM beta-mercaptoethanol, 0.6 mM cysteine and 0.6 mM cystine on 1) intracellular GSH level after IVM, 2) after IVF, 3) in 6 to 8-cell embryos and 4) on embryo development. In oocytes after IVM and in presumptive zygotes after IVF, intracellular GSH levels were significantly higher in the treated groups (P < 0.05). While, GSH content in 6 to 8-cell embryos was similar among treatment groups (P > 0.05). Differences in cleavage rates and the percentage of embryos that developed to morula and blastocyst stages were significantly higher (P < 0.05) for treated oocytes than for those matured in the control medium. We conclude from the results that the high intracellular GSH levels after induction of GSH synthesis in bovine IVM by thiol compounds remain during IVF and are still present at the beginning of IVC, improving developmental rates. Moreover, the results indicate that this metabolic pathway is an important component of the cytoplasmic maturation process that affects the subsequent steps of in vitro embryo production. 相似文献
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In vitro evaluation and pregnancy rates after vitrification of in vitro produced bovine embryos 总被引:2,自引:0,他引:2
The efficacy of different vitrification solutions to cryopreserve in vitro-produced bovine blastocysts was evaluated based on in vitro development of embryos in culture and on in vivo development of embryos transferred into recipients. In the first experiment, 2 vitrification solutions were compared: propylene glycol + glycerol (Pg + Gly) and ethylene glycol + Ficoll + sucrose (EFS). Differences in the overall development and hatching rates in favor of EFS were found (56.4 vs 33.3% and 35.4 vs 13.3%; P < 0.05). In the second experiment, 3 vitrification solutions were compared: EFS, modified EFS (EFSm) and ethylene glycol + glycerol (Eg + Gly). The vitrification solutions EFSm and Eg + Gly yield higher hatching rates than did EFS (57.7 vs 59.6 vs 35.7%; P < 0.05). The last experiment was designed to compare in vivo 2 vitrification solutions: EFSm and Eg + Gly. There were no differences between them based on the results obtained after transfer (35.2 vs 43.7%). The vitrification solutions EFSm and Eg + Gly have resulted in good pregnancy rates. These results demonstrated that vitrification can be used successfully in the cryopreservation of in-vitro produced bovine embryos, and it might be considered for use in commercial programs. 相似文献
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Reactions of the adduct UCl3·(THF)x (THF = tetrahydrofuran) with compounds of the type K[HnBL4?n], where L = pyrazole or 3,5-dimethylpyrazole, are presented. Based on the results obtained the two compounds UCl2H2BPz2·THF and UCl2HBPz3·THF were isolated. 相似文献
47.
Joana T. de Oliveira Ana L. Santos Catarina Gomes Rita Barros Cláudia Ribeiro Nuno Mendes Augusto J. de Matos M. Helena Vasconcelos Maria José Oliveira Celso A. Reis Fátima G?rtner 《PloS one》2015,10(4)
Oseltamivir phosphate is a widely used anti-influenza sialidase inhibitor. Sialylation, governed by sialyltransferases and sialidases, is strongly implicated in the oncogenesis and progression of breast cancer. In this study we evaluated the biological behavior of canine mammary tumor cells upon oseltamivir phosphate treatment (a sialidase inhibitor) in vitro and in vivo. Our in vitro results showed that oseltamivir phosphate impairs sialidase activity leading to increased sialylation in CMA07 and CMT-U27 canine mammary cancer cells. Surprisingly, oseltamivir phosphate stimulated, CMT-U27 cell migration and invasion capacity in vitro, in a dose-dependent manner. CMT-U27 tumors xenograft of oseltamivir phosphate-treated nude mice showed increased sialylation, namely α2,6 terminal structures and SLe(x) expression. Remarkably, a trend towards increased lung metastases was observed in oseltamivir phosphate-treated nude mice. Taken together, our findings revealed that oseltamivir impairs canine mammary cancer cell sialidase activity, altering the sialylation pattern of canine mammary tumors, and leading, surprisingly, to in vitro and in vivo increased mammary tumor aggressiveness. 相似文献
48.
Izabelle Silva Rehfeld Maria Isabel Maldonado Coelho Guedes Ana Luiza Soares Fraiha Aristóteles Gomes Costa Ana Carolina Diniz Matos Aparecida Tatiane Lino Fiúza Zélia Inês Portela Lobato 《PloS one》2015,10(5)
Bovine vaccinia (BV) is a zoonosis caused by Vaccinia virus (VACV), which affects dairy cattle and humans. Previous studies have detected the presence of viable virus particles in bovine milk samples naturally and experimentally contaminated with VACV. However, it is not known whether milk contaminated with VACV could be a route of viral transmission. However, anti-Orthopoxvirus antibodies were detected in humans from BV endemic areas, whom had no contact with affected cows, which suggest that other VACV transmission routes are possible, such as consumption of contaminated milk and dairy products. Therefore, it is important to study the possibility of VACV transmission by contaminated milk. This study aimed to examine VACV transmission, pathogenesis and shedding in mice orally inoculated with experimentally contaminated milk. Thirty mice were orally inoculated with milk containing 107 PFU/ml of VACV, and ten mice were orally inoculated with uncontaminated milk. Clinical examinations were performed for 30 consecutive days, and fecal samples and oral swabs (OSs) were collected every other day. Mice were euthanized on predetermined days, and tissue and blood samples were collected. Nested-PCR, plaque reduction neutralization test (PRNT), viral isolation, histopathology, and immunohistochemistry (IHC) methods were performed on the collected samples. No clinical changes were observed in the animals. Viral DNA was detected in feces, blood, OSs and tissues, at least in one of the times tested. The lungs displayed moderate to severe interstitial lymphohistiocytic infiltrates, and only the heart, tonsils, tongue, and stomach did not show immunostaining at the IHC analysis. Neutralizing antibodies were detected at the 20th and 30th days post infection in 50% of infected mice. The results revealed that VACV contaminated milk could be a route of viral transmission in mice experimentally infected, showing systemic distribution and shedding through feces and oral mucosa, albeit without exhibiting any clinical signs. 相似文献
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Luís Guedes-Martins Rita Gaio Joaquim Saraiva Sofia Cerdeira Liliana Matos Elisabete Silva Filipe Macedo Henrique Almeida 《PloS one》2015,10(3)