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41.
Effect of pharmacological concentrations of zinc oxide with or without the inclusion of an antibacterial agent on nursery pig performance 总被引:4,自引:0,他引:4
Hill GM Mahan DC Carter SD Cromwell GL Ewan RC Harrold RL Lewis AJ Miller PS Shurson GC Veum TL;NCR- Committee on Swine Nutrition 《Journal of animal science》2001,79(4):934-941
A study involving nine research stations from the NCR-42 Swine Nutrition Committee used a total of 1,978 crossbred pigs to evaluate the effects of dietary ZnO concentrations with or without an antibacterial agent on postweaning pig performance. In Exp. 1, seven stations (IA, MI, MN, MO, NE, ND, and OH) evaluated the efficacy of ZnO when fed to nursery pigs at 0, 500, 1,000, 2,000, or 3,000 mg Zn/kg for a 28-d postweaning period. A randomized complete block experiment was conducted in 24 replicates using a total of 1,060 pigs. Pigs were bled at the 28-d period and plasma was analyzed for Zn and Cu. Because two stations weaned pigs at < 15 d (six replicates) and five stations at > 20 d (18 replicates) of age, the two sets of data were analyzed separately. The early-weaned pig group had greater (P < 0.05) gains, feed intakes, and gain:feed ratios for the 28-d postweaning period as dietary ZnO concentration increased. Later-weaned pigs also had increased (P < 0.01) gains and feed intakes as the dietary ZnO concentration increased. Responses for both weanling pig groups seemed to reach a plateau at 2,000 mg Zn/kg. Plasma Zn concentrations quadratically increased (P < 0.01) and plasma Cu concentrations quadratically decreased (P < 0.01) when ZnO concentrations were > 1,000 mg Zn/kg. Experiment 2 was conducted at seven stations (KY, MI, MO, NE, ND, OH, and OK) and evaluated the efficacy of an antibacterial agent (carbadox) in combination with added ZnO. The experiment was a 2 x 3 factorial arrangement in a randomized complete block design conducted in a total of 20 replicates. Carbadox was added at 0 or 55 mg/kg diet, and ZnO was added at 0, 1,500, or 3,000 mg Zn/ kg. A total of 918 pigs were weaned at an average 19.7 d of age. For the 28-d postweaning period, gains (P < 0.01), feed intakes (P < 0.05), and gain:feed ratios (P < 0.05) increased when dietary ZnO concentrations increased and when carbadox was added. These responses occurred in an additive manner. The results of these studies suggest that supplemental ZnO at 1,500 to 2,000 mg Zn/kg Zn improved postweaning pig performance, and its combination with an antibacterial agent resulted in additional performance improvements. 相似文献
42.
Moore GE Burkman KD Carter MN Peterson MR 《Journal of the American Veterinary Medical Association》2001,219(2):209-214
OBJECTIVE: To determine causes of death or reasons for euthanasia in a population of military working dogs. DESIGN: Retrospective study. ANIMALS: 927 military working dogs. PROCEDURE: Records of all military working dogs that died during the period from 1993 to 1996 were evaluated for cause of death or reason for euthanasia by review of necropsy and histopathology reports, death certificates, and daily clinical treatment sheets. A single primary cause of death or euthanasia was determined. RESULTS: Although sexually intact male dogs were more numerous in the study population, castrated male dogs typically lived longer than spayed females or sexually intact males. Leading causes of death or euthanasia (76.3% of all dogs) were appendicular degenerative joint disease, neoplasia, spinal cord disease, nonspecific geriatric decline, and gastric dilatation-volvulus. Compared with German Shepherd Dogs, Belgian Shepherd Dogs were at increased risk for death attributable to neoplasia, behavior, and respiratory tract disease. German Shepherd Dogs had nearly twice the risk for death associated with spinal cord diseases, compared with Belgian Shepherd Dogs. CONCLUSIONS AND CLINICAL RELEVANCE: For most military working dogs, death or euthanasia results from a few diseases commonly associated with advanced age. Some breed differences in risk for these diseases may exist, which clinicians should consider in the procurement and long-term management of these dogs. 相似文献
43.
Hewicker-Trautwein M Carter SD Bennett D Kelly DF 《Veterinary immunology and immunopathology》1999,67(4):341-357
The study describes the distribution of canine leucocyte antigens in synovial membrane biopsies from six dogs with canine rheumatoid arthritis (CRA) and from eight dogs with osteoarthritis (OA) secondary to spontaneous rupture of the cranial cruciate ligament (CCL) (n = 5) or patellar luxation (n = 3). Synovial membranes from five dogs without evidence of joint lesions were used as control tissues. In the subsynovium of dogs with normal joints CD5+, CD4+, CD8+ and alpha beta TCR+ lymphocytes were present only in low numbers. With monoclonal antibody (mAb) to MHC class II antigen, either none or up to 20-30% of synovial lining cells were immunoreactive. Furthermore, scattered MHCII+ stromal cells were seen in the deeper subsynovial layer. In synovial membrane biopsies from dogs with CRA numerous diffusely and perivascularly distributed CD5+ lymphocytes were found in the subsynovium. CD4+ cells outnumbered CD8+ cells and were more numerous in the perivascular areas. In all the CRA cases examined, there were markedly higher numbers of alpha beta TCR+ cells compared with gamma delta TCR+ cells. With mAb to CD21, low numbers of immunoreactive lymphocytes were demonstrated. In all the CRA cases, a marked increase of MHC class II antigen expression was noted. In the majority of samples, 50% or more than 90% of the synovial lining cells were strongly MHC class II+. Throughout the subsynovial layer there were numerous MHC class II+ cells and included those with dendritic morphology and inflammatory mononuclear cells. Furthermore, marked perivascular immunoreactivity for MHC class II antigen was found. In biopsies from dogs with OA, there were markedly lower numbers of subsynovial CD5+, CD4+ and CD8+ lymphocytes. T-cells were mainly diffusely distributed. In three of the eight OA dogs examined, there was an increased percentage of synovial lining cells expressing MHC class II. The majority of OA cases had subsynovial major histocompatibility complex (MHC) class II+ cells with a dendritic morphology. 相似文献
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T. C. Carter 《British poultry science》1968,9(4)
Manual of Procedures in Quantitative Genetics, by Walter A. Becker. Second edition, 1967. Washington State University, Pullman, Washington. Price $4.00. 相似文献
48.
Carter LJ 《Science (New York, N.Y.)》1975,188(4191):914-916
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