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51.
NICK A. HUGGONS ROBIN J. W. BELL SARAH M. PUCHALSKI 《Veterinary radiology & ultrasound》2011,52(1):53-60
We compared the information gained from computed tomography (CT) vs. radiography in horses with nonneoplastic disease of the mandible. We hypothesized that CT would provide additional diagnostic information. Medical records, radiographs, and CT images of horses with nonneoplastic mandibular disease evaluated between 1994 and 2008 were reviewed. Nineteen horses were identified; 11 had a tooth root abscess and related disease, four had a fracture of the teeth and/or mandible, and four had a nonneoplastic mass. Both CT images and radiographs allowed identification of diseased teeth that appeared clinically normal otherwise. CT allowed identification of teeth that were clinically affected but appeared normal radiographically. Parameters such as tooth pulp involvement, lamina dura destruction, presence of bone fragments, lingual and buccal mandibular bone periosteal reaction, and cortical bone destruction were more conspicuous with CT. Performing radiography and CT in horses with nonneoplastic mandibular disease provides a more complete evaluation than either technique alone. CT contributes additional information that could otherwise be overlooked with radiographs alone in horses with a mandibular fracture. CT provides ancillary information to radiographs in horses with dental infection or a nonneoplastic mass of the mandible. 相似文献
52.
A waste water reuse engineering was designed and then operated in Hongshan,a small town in Zhejiang Province,China,in order to solve pollution and shortage of water resources due to the development of rural enterprises.The results showed that series-structure design and cycling model were two effective modes of saving water and decreasing pollutants into environment,and wetland strategy should be a component part of the integrated planning for waste water reuse of rural enterprises.This case study could provide a basis for the optimum utilization and pollution avoidance of water resources. 相似文献
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Developing chick embryos from the stage of primitive-streak formation make ribosomal (28S and 16S) RNA. The size and composition of the RNA appears to be constant throughout the first 7 days of development. 相似文献
58.
Abstract. Populations of Penaeus stylirostris , free of infectious hypodermal and haematopoietic necrosis virus (IHHNV), were divided into five size groups (PL2 [2-day-oldpostlarvae, approximately 5.0 mg], 3.7 g, 14.5 g, 21.3 g and 36.9 gaverage initial weight), and experimentally exposed to IHHNV per or . Statistical comparisons (histologically-derived) of infection severity ratings from six weekly sample periods indicated the relative abundance of pathognomonic Cowdry type A intranuclear inclusion bodies (and, hence, the severity of the disease) differed between sizes. The results of comparisons showed a tendency for larger animals to have a significantly lower prevalence of inclusion bodies and associated histopathology than smaller animals. The results also indicated that the smaller (average weight) the group was, the shorter was the period of time from initial exposure to the first histological detection of the disease. Thus, the larger (in average weight) a population of P. stylirostris is upon initial exposure to IHHNV, the less acute will be disease manifestation within a given time and the longer will be the period before the disease is first histologically detectable. A predictive equation that defines the epizootiological relationship of IHHN disease within an intensively cultured population of P. stylirostris is also presented. 相似文献
59.
土壤微生物群落结构与多样性对农田集约化管理程度降低的响应 总被引:12,自引:0,他引:12
ZHANG Wei-Jian RUI Wen-Yi C. TU H. G. DIAB F. J. LOUWS J. P. MUELLER N. CREAMER M. BELL M. G. WAGGER S. HU 《土壤圈》2005,15(4):440-447
Using a scheme of agricultural fields with progressively less intensive management (deintensification), different management practices in six agroecosystems located near Goldsboro, NC, USA were tested in a large-scale experiment, including two cash-grain cropping systems employing either tillage (CT) or no-tillage (NT), an organic farming system (OR), an integrated cropping system with animals (IN), a successional field (SU), and a plantation woodlot (WO). Microbial phospholipid fatty acid (PLFA) profiles and substrate utilization patterns (BIOLOG ECO plates) were measured to examine the effects of deintensification on the structure and diversity of soil microbial communities. Principle component analyses of PLFA and BIOLOG data showed that the microbial community structure diverged among the soils of the six systems.Lower microbial diversity was found in lowly managed ecosystem than that in intensive and moderately managed agroecosystems, and both fungal contribution to the total identified PLFAs and the ratio of microbial biomass C/N increased along with agricultural deintensification. Significantly higher ratios of C/N (P 〈 0.05) were found in the WO and SU systems, and for fungal/bacterial PLFAs in the WO system (P 〈 0.05). There were also significant decreases (P 〈 0.05) along with agricultural deintensification for contributions of total bacterial and gram positive (G+) bacterial PLFAs.Agricultural deintensification could facilitate the development of microbial communities that favor soil fungi over bacteria. 相似文献
60.
G. KELMER G. C. BELL T. MARTIN‐JIMENEZ A. M. SAXTON C. CATASUS S. B. ELLIOT B. MEIBOHM 《Journal of veterinary pharmacology and therapeutics》2013,36(3):236-240
Previous studies have shown that regional limb perfusion (RLP) using the palmar digital (PD) vein delivers therapeutic concentration of amikacin to the distal limb. Our hypothesis was that using the cephalic and saphenous veins for RLP will enable delivery of therapeutic concentrations of amikacin to the distal limb. Nineteen healthy horses participated in the study. The cephalic, saphenous, or PD vein was used to perfuse the limb with amikacin. Two grams of amikacin was used for RLP using the saphenous and the cephalic veins, and one gram was used in the PD vein. Synovial samples were collected from the metacarpo‐/metatarsophalangeal (MCP/MTP) joint, and blood samples were collected from the jugular vein. Maximum concentration (Cmax) of amikacin in the MCP/MTP joint using the cephalic and the saphenous vein was 277 and 363 mg/L, respectively. The amikacin concentrations achieved in the synovial fluid of the MCP/MTP joint in the current study were between 69 and 91 times the minimally inhibitory concentration of common susceptible bacterial pathogens causing orthopedic infections in horses. To conclude, this study shows that use of the proximal veins for RLP to treat distal limb infections is a viable alternative to using the palmar or plantar digital vein. 相似文献