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151.
J.H.F. Pontes K.C.F. Silva A.G. Rigo G.M.G. Santos J.P.F. Porcionato F.S. Faifer J.L. Schenk 《Theriogenology》2010,74(8):1349-1355
Herein we describe a large-scale commercial program for in vitro production of embryos from dairy Bos taurus, Bos indicus, and indicus-taurus donors, using sexed sperm. From 5,407 OPU, we compared the number of recovered oocytes (n = 90,086), viable oocytes (n = 64,826), and embryos produced in vitro from Gir (Bos indicus, n = 617), Holstein (Bos taurus, n = 180), 1/4 Holstein × 3/4 Gir (n = 44), and 1/2 Holstein-Gir (n = 37) crossbred cows, and the pregnancy rate of recipient cows. Viable oocytes were in vitro matured (24 h at 38.8 °C, 5% CO2 in air) and fertilized by incubating them for 18 to 20 h with frozen-thawed sexed sperm (X-chromosome bearing) from Gir (n = 8) or Holstein (n = 7) sires (2 × 106 sperm/dose). Embryos were cultured in similar conditions of temperature and atmosphere as for IVM, with variable intervals of culture (between Days 2 and 5) completed in a portable incubator. All embryos were transferred fresh, after 24 to 72 h of transportation (up to 2,000 km). On average, 16.7 ± 6.3 oocytes (mean ± SEM) were obtained per OPU procedure and 72.0% were considered viable. Total and viable oocytes per OPU procedure were 17.1 ± 4.5 and 12.1 ± 3.9 for Gir cows, 11.4 ± 3.9 and 8.0 ± 2.7 for Holstein cows, 20.4 ± 5.8 and 16.8 ± 5.0 for 1/4 Holstein × 3/4 Gir, and 31.4 ± 5.6 and 24.3 ± 4.7 for 1/2 Holstein-Gir crossbred females (P < 0.01). The mean number of embryos produced by OPU/IVF and the pregnancy rates were 3.2 (12,243/ 3,778) and 40% for Gir cows, 2.1 (2,426/1,138) and 36% for Holstein cows, 3.9 (1,033/267) and 37% for 1/4 Holstein × 3/4 Gir, and 5.5 (1,222/224), and 37% for 1/2 Holstein-Gir. In conclusion, we compared oocyte yield from two levels of indicus-taurus breeds and demonstrated the efficiency of sexed sperm for in vitro embryo production. Culturing embryos during long distance transportation was successful, with potential for international movement of embryos. 相似文献
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Tetyana Ivanovska Andrea Schenk André Homeyer Meihong Deng Uta Dahmen Olaf Dirsch Horst K Hahn Lars Linsen 《BMC bioinformatics》2010,11(1):124
Background
Quantification of different types of cells is often needed for analysis of histological images. In our project, we compute the relative number of proliferating hepatocytes for the evaluation of the regeneration process after partial hepatectomy in normal rat livers. 相似文献154.
Introduction
There is an ever-increasing need for animal models to evaluate efficacy and safety of new therapeutics in the field of rheumatoid arthritis (RA). Particularly for the early preclinical evaluation of human-specific biologicals targeting the progressive phase of the disease, there is a need for relevant animal models. In response to this requirement we set out to develop a model of collagen-induced arthritis (CIA) in a small-sized nonhuman primate species (300 to 400 g at adult age); that is, the common marmoset (Callithrix jacchus). 相似文献155.
Christopher Tanner Sarah Hunter Justin Reel Thomas Parham Mike Naylor Lee Karrh Kathryn Busch Rebecca R. Golden Mark Lewandowski Nancy Rybicki Edward Schenk 《Restoration Ecology》2010,18(4):538-548
Approximately 90,000 shoots of eelgrass (Zostera marina) were planted over 3 years (2003–2005) at Piney Point (PP) in the lower Potomac River estuary in the Chesapeake Bay (mid‐Atlantic coast of North America) following 3 years of habitat evaluation using a Preliminary Transplant Suitability Index (PTSI) and test plantings. Initial survival was high for the 2003 and 2004 plantings; however, most of the eelgrass died during the summer following the fall planting. Habitat quality and restoration success were monitored for the 2005 plantings and compared to a nearby restoration site (St. George Island [SGI]). Eelgrass planted at PP in the fall of 2005 declined through the summer of 2006 with some recovery in the spring of 2007, but was gone by the end of the summer of 2007. The summer decline from late July to mid‐August of 2006 coincided with water temperatures greater than 30°C, hypoxic oxygen (0–3 mg/L) concentrations, and low percent light at leaf level (PLL < 15%). Epiphyte loads were much heavier at PP than at SGI, despite similar water quality. We suggest that this was the result of higher wave exposure at PP. All of these factors are likely to have contributed to the mortality of the 2005 plantings. Submerged aquatic vegetation habitat quality based on the PTSI, median PLL during the growing season, and test plantings did not explain the decline of the plantings. Restoration site selection criteria should be expanded to include the effects of wave exposure on self‐shading and epiphyte loads, and the potential for both short‐term exposures to stressful conditions and long‐term changes in habitat quality. 相似文献
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157.
Sophie Köndgen Svenja Schenk Georg Pauli Christophe Boesch Fabian H. Leendertz 《EcoHealth》2010,7(3):332-341
To diagnose respiratory disease among wild great apes, there is a need for noninvasive diagnostic methods. Therefore, we analyzed fecal samples from habituated chimpanzees from Taï National Park, Côte d’Ivoire. Samples had been collected during four distinct outbreaks: two with known aetiology (March 2004 and February 2006) and two with unknown aetiology (October 2004 and August 2005). Fecal samples were screened by polymerase chain reaction (PCR) for the presence of human metapneumovirus (HMPV) and human respiratory syncytial virus (HRSV), two paramyxoviruses previously found in lung tissue of chimpanzees that died due to respiratory disease. In the March 2004 outbreak, 72% of the tested individuals were positive for HMPV, and during the 2006 epidemic, 25% tested HRSV-positive. In the outbreaks where no causative pathogen was previously known, fecal samples tested positive for either HRSV or HMPV, showing that reinfection occurred. Virus sequences were generated and compared with sequences previously found in tissue; nearly identical virus sequences in both tissue and fecal samples were found. These results demonstrate that fecal samples collected during outbreak times can be used for the diagnostic and phylogenetic analysis of HMPV and HRSV. Using such diagnostic tools, systematic noninvasive disease investigation of respiratory outbreaks in wild great apes becomes possible. The methods presented here may also be applied for the investigation of further acute diseases in great apes and other species. 相似文献
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Over 3500 patients with recent onset inflammatory polyarthritis (IP) have been recruited by the Norfolk Arthritis Register
(NOAR) since 1990. Longitudinal data from this cohort have been used to examine the prevalence and predictors of remission,
functional disability, radiological outcome, cardiovascular mortality and co-morbidity and the development of non-Hodgkin's
lymphoma. Rheumatoid factor titre, high baseline C-reactive protein and high baseline HAQ score are all predictors of a poor
outcome. There is a strong association between possession of the shared epitope and the development of erosions. Patients
who satisfy the American College of Rheumatology criteria for rheumatoid arthritis (RA) have a worse prognosis than those
who do not. However, it appears that these patients are a poorly defined subset of all those with IP rather than having an
entirely separate disease entity. New statistical techniques offer exciting possibilities for using longitudinal datasets
such as NOAR to explore the long-term effects of treatment in IP and RA. 相似文献