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SUMMARY A case of vaginal prolapse in a South Australian Sea Lion is described. Conservative treatment proved unsuccessful, and an ovariohysterectomy was performed. Problems concerning anaesthesia, surgery and post-operative management of this marine species are discussed.  相似文献   
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Giardia isolates from eight horses from New York State (NY), USA and two horses from Western Australia (WA) were genetically characterized at the SSU-rDNA and triose-phosphate isomerase (TPI) genes. Phylogenetic analysis of the TPI gene provided strong support for the placement of both isolates of Giardia from horses in WA and a single isolate from a horse in NY within the assemblage AI genotype of G. duodenalis. Another two isolates from horses in NY placed within the assemblage AII genotype of G. duodenalis. Phylogenetic analysis of the TPI gene also provided strong bootstrap support for the placement of four G. duodenalis isolates from horses in NY into a potentially host-specific sub-assemblage of assemblage BIV. The results of this study are consistent with previous studies showing that assemblages AI and AII of G. duodenalis provide the greatest potential zoonotic risk to humans. Horses may therefore constitute a potential source for human infection of Giardia either directly or via watersheds.  相似文献   
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Nine fatal cases of canine American trypanosomiasis (Chagas' disease) were encountered from November, 1972, through November, 1975. Of the 9 cases, 7 occurred in dogs from 5 central Texas counties, and all but one case was diagnosed during the months of September, October, or November. The source of infection was discovered in only one case--that being a doghouse heavily infested with Triatoma lectularius occulta. Each of 6 bugs collected had infective forms of the protozoan, Trypanosoma cruzi. Trypanosomiasis usually is not considered in the differential clinical diagnosis of cardiac dysfunction in man or other mammals in the United States. An antemortem diagnosis was made in only 1 of the 9 dogs, with diagnosis in the remaining dogs being made at necropsy. The predominant microscopic lesion in all dogs was necrotizing granulomatous myocarditis associated with the amastigotes of T cruzi.  相似文献   
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A 1.5-year-old Suffolk ewe with acute onset of incoordination and blindness unresponsive to antibiotic treatment was examined at necropsy. The meninges were congested, opaque, and thick. Microscopically, focal areas of hypercellularity in the left cortical gray matter and the meninges were observed. The inflammatory response consisted of gliosis and perivascular cuffing (lymphocytes, plasma cells, and variable numbers of eosinophils). An amebic organism in 2 life stages was found in the cerebral parenchyma. Numerous large (15 to 35 microns in diameter) organisms, interpreted as trophozoites, were characterized by vacuolated cytoplasm and small nuclei with a prominent eosinophilic nucleolus (karyosome). The smaller (10 to 17 microns in diameter) encysted stage was surrounded by a capsule-like membrane, and contained a large central body sometimes surrounded by a clear halo. Immunofluorescence studies for amebic antigens were strongly positive for an ameba recently isolated in human beings and baboons (Leptomyxid sp).  相似文献   
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OBJECTIVE: To determine anesthetic techniques and the drugs used to provide anesthesia and analgesia to reptiles. DESIGN: Mail-out questionnaire. SAMPLE POPULATION: 367 members of the Association of Reptile and Amphibian Veterinarians. PROCEDURE: 1,091 members listed in the 2002 directory of the Association of Reptile and Amphibian Veterinarians were asked to complete a questionnaire regarding anesthesia and analgesia. RESULTS: 367 of 1,091 (33.6%) individuals completed the questionnaire; 88.8% used inhalants (particularly isoflurane) for anesthesia, and ketamine, propofol, and butorphanol were the most commonly used injectable agents. Intubation, fluids, and having a dedicated anesthetist were most commonly used for patient support, and pulse oximetry and Doppler ultrasonography were most commonly used for monitoring. Respiratory depression, difficulty monitoring anesthetic depth, prolonged recovery, and hypothermia were the most frequent complications. Nearly all respondents believed that reptiles feel pain, but analgesics were used infrequently for many reasons. CONCLUSIONS AND CLINICAL RELEVANCE: Providing anesthesia in reptiles is difficult, especially regarding anesthetic depth and vital parameters, and methods of support are used less frequently than in domestic species. Provision of analgesia is uncommon. Research regarding pain and its assessment, response to analgesics, and drug pharmacokinetics is needed. Dissemination of this information to practitioners needs to be improved for enhancement of the standard of care for reptiles.  相似文献   
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Artificial spin ice, made up of planar nanostructured arrays of simple ferromagnetic bars, is a playground for rich physics associated with the spin alignment of the bars and spin texture associated with the magnetic frustration at the bar vertices. The phase diagram is exotic, showing magnetic monopole-like defects and liquid and solid phases of spins arranged in loop states with predicted chiral order. We show that magnetotransport measurements in connected honeycomb structures yield the onset of an anomalous Hall signal at 50 kelvin. The temperature scale can be attributed to the long-range dipolar ice phase. The topological Hall signal arises because chiral loops form at the sample edges, indicating a generic route to exotic states via nanoarray edge structure.  相似文献   
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Cardiomyopathy developed in mice deficient for α-kinase 3 (ALPK3), a nuclear kinase previously implicated in the differentiation of cardiomyocytes. Alpk3 (-/-) mice were produced according to normal Mendelian ratios and appeared normal except for a nonprogressive cardiomyopathy that had features of both hypertrophic and dilated forms of cardiomyopathy. Cardiac hypertrophy in Alpk3 (-/-) mice was characterized by increased thickness of both left and right ventricular (LV and RV) walls and by markedly increased heart weight and increased heart weight/body weight and heart weight/tibia length ratios. Magnetic resonance imaging studies confirmed the increased thickness in both septal and LV free walls at end-diastole, although there was no significant change in LV wall thickness at end-systole. Myocardial hypertrophy was the predominant feature in Alpk3 (-/-) mice, but several changes more typically associated with dilated cardiomyopathy included a marked increase in end-diastolic and end-systolic LV volume, as well as reduced cardiac output, stroke volume, and ejection fractions, suggesting LV chamber dilation. Magnetic resonance imaging showed a 50% reduction in both septal and free wall LV contractility in Alpk3 (-/-) mice. Interstitial fibrosis and inflammation were notably absent in Alpk3 (-/-) mice; however, light and electron microscopy revealed altered cardiomyocyte architecture, characterized by reduced numbers of abnormal intercalated discs being associated with mild disarray of myofibrils. These lesions could account for the impaired contractility of the myofibrillar apparatus and contribute to the pathogenesis of cardiomyopathy in Alpk3 (-/-) mice.  相似文献   
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