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61.
OBJECTIVE: To identify underlying medical conditions in cats with a presumptive diagnosis of psychogenic alopecia. DESIGN: Case series. ANIMALS: 21 adult cats referred with a presumptive diagnosis of psychogenic alopecia. PROCEDURES: A detailed behavior and dermatologic questionnaire was completed by the primary caregiver, and complete behavioral and dermatologic examinations were performed. A standard diagnostic testing protocol that included cytologic examination of skin scrapings, fungal culture of hairs, evaluation of responses to parasiticides and an exclusion diet, assessment for atopy and endocrinopathies, and histologic examination of skin biopsy specimens was used to establish a definitive diagnosis in all cats. Cats that did not respond to an elimination diet were treated with methylprednisolone acetate to determine whether pruritus was a factor. RESULTS: Medical causes of pruritus were identified in 16 (76%) cats. Only 2 (10%) cats were found to have only psychogenic alopecia, and an additional 3 (14%) cats had a combination of psychogenic alopecia and a medical cause of pruritus. An adverse food reaction was diagnosed in 12 (57%) cats and was suspected in an additional 2. All cats with histologic evidence of inflammation in skin biopsy specimens were determined to have a medical condition, but of 6 cats without histologic abnormalities, 4 had an adverse food reaction, atopy, or a combination of the 2, and only 2 had psychogenic alopecia. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that psychogenic alopecia is overdiagnosed in cats. Thorough diagnostic testing should be done before ascribing a behavioral cause to hair loss in cats.  相似文献   
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Transmission electron microscopic study of endogenous development of Eimeria turcicus Upton, McAllister and Freed, 1988 (Eimeriorina, Apicomplexa), in the gall bladder epithelium of the gecko Hemidactylus turcicus from Israel, revealed merogony and gamogony stages which induce hypertrophy and displacement of their host cell from the epithelial layer. Meronts yield over 70 merozoites. Microgametes are biflagellated. Macrogamonts contain both types of wall-forming bodies (WF1, 2). In the zygote, disaggregation of WF1s coincide with the onset of oocyst wall formation, while WF2s persist. A multilayered wall is formed at the first stage of the wall formation. Subsequently, 5 membranes (M1-5) are formed at the surface of the zygote like in other elmerine coccidia. The oocyst wall appears to be formed by M3 and M4.  相似文献   
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This study aimed to evaluate the contribution of three diatom species on the lipid content of bioflocs, their permanence on the bioflocs and influence on the growth performance of juvenile shrimps. Juveniles of Litopenaeus vannamei were reared (30 days; three replicates per treatment) in biofloc systems inoculated with diatoms Amphora coffeaeformis (A), Cylindrotheca closterium (C), Conticribra weissflogii (W), or biofloc only (BF, chlorophycean rich). Water quality parameters were monitored daily and the microbiota on days 1, 10, 20 and 30. The lipid content and fatty acid profiles of bioflocs were analyzed at the end of the experiment. Shrimp survival rate (99%) at treatment A was significantly higher than at BF. The bioflocs in A treatment presented the highest lipid content, differing significantly from BF and W. The content of EPA (20:5) (n‐3) was significantly higher in A and lower in BF, while linoleic acid (18:2) (n‐6) was significantly higher in BF. The results indicate that high cell density of diatoms can be successfully maintained with silicate addition in biofloc systems and that the pennate A. coffeaeformis and the centric C. weissflogii are potentially better suited than the pennate C. closterium as food supplements for shrimp diets in biofloc nurseries system.  相似文献   
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The objectives of this study were to evaluate if vitrified porcine spermatozoa are able to maintain their capacity to produce zygotes in vitro using intracytoplasmic sperm injection (ICSI) and to evaluate the zygote development in two in vitro atmospheric conditions: 5% CO2 and tri‐gas. A group of porcine oocytes maturated in vitro were injected with vitrified‐warmed sperm (treatment group) and another group, with sperm diluted and conserved at 17°C (control group). To evidence parthenogenetic activation, some oocytes were submitted to a Sham test. The injected oocytes were cultured in G1 medium at 38°C, 100% humidity and 5% CO2 or tri‐gas. No significant differences (> .05) were observed in embryo development between the oocytes injected with vitrified‐warmed sperm (31.8%; 36/113), and those injected with semen diluted and conserved at 17°C (35.5%; 32/90), when cultured in 5% CO2 or under tri‐gas atmosphere (42.9%; 39/91 vs. 34.2%; 26/76, respectively). No significant differences (p > .05) were observed in the percentage of pronuclei (PN) obtained between 5% CO2 and tri‐gas, within each treatment either. Of the 52 oocytes submitted to the Sham test, only two presented a female PN (activation) indicating that the PN observed in the treatment group were a product of fertilization and not parthenogenetic activation. To conclude, porcine sperm vitrified using spheres, at a concentration of 5 × 106 spermatozoa/ml in TALP medium with 1% bovine serum albumin (BSA), conserve condensed and intact chromatin capable of producing early embryo development up to the pronuclear stage.  相似文献   
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SUMMARY: Psittacine beak and feather disease virus (PBFDV) was administered to adult galahs ( Eolophusroselcapillus ) by mouth or by intramuscular injection. Concentration of PBFDV antibodies in serum and excretion of PBFDV were monitored by haemagglutlnation inhibition (HI) and haemagglutination (HA) respectively. After oral administration, 17 of 18 galahs remained clinically normal and a small rise in antibody titre was detected in 3 of 18 birds. After intramuscular administration, antibody was detected in all birds. PBFDV was not detected in the feather dander of birds in either group. One bird developed diarrhoea and high faecal HA titres within 4 days of oral administration and then died. Adult and nestling cockatoos were vaccinated with an experimental inactivated double-oil emulsion vaccine. PBFDV antibody responses are comparable to those induced by a primary-oil emulsion vaccination regimen using Freund's adjuvants. Both vaccines protected nestlings. Three sibling wild-caught sulphur-crested cockatoos were vaccinated but died of PBFD before experimental challenge despite antibody responses in all birds. Unvaccinated control chicks developed acute PBFD within 4 weeks of challenge, probably from PBFDV-induced hepatitis since high concentrations of PBFDV were detected in their livers.  相似文献   
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SUMMARY Simple and sensitive haemagglutination and haemagglutination Inhibition assays were developed for psittacine beak and feather disease (PBFD) virus and serum antibody, respectively. The assays were used in the examination of samples from 73 birds clinically affected with PBFD. High antigen titres (log2 9 to log2 12) were detected In feathers, faeces and cloacal contents of PBFD-affected birds. Antigen was not detected In either faecal or feather samples from 20 normal galahs (Eolophus roselcapillus) and 9 normal sulphur crested cockatoos (Cacatua galerita). After kaolin treatment and haemadsorption of serum, haemagglutination inhibition (HI) antibody titres could not be detected in serum from 42 PBFD-affected birds, whereas serum HI titres from 64 normal psittacine birds ranged from less than log2 1 to log2 8. Serum and yolk HI antibody responses of 6 PBFD virus-inoculated layer hens were measured. Pre-inoculation chicken sera contained high concentrations of non-specific haemagglutination inhibitors (not detected in chloroform-extracted yolk), which were removed by kaolin treatment and haemadsorption.  相似文献   
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