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An evaluation of 157 dogs with humeral fractures was performed. Cocker spaniels were more likely to have humeral condylar fractures (HCFs) than other breeds ( P < .0001). Male cocker spaniels were at increased risk ( P < .001). Cocker spaniels had more bilateral HCFs than other breeds of dogs ( P < .001). Eighteen dogs (17 purebred spaniels and 1 crossbred spaniel) with HCFs of unknown cause or occurring with normal activity were further studied, using radiography of their humeral condyle bilaterally (n = 18), computed tomography (n = 3), biopsy (n = 2), bone scintigraphy (n = 2), and genetic evaluation (n = 8). Fourteen of these 18 dogs had a nonfractured contralateral condyle. Twelve (86%) of the 14 nonfractured humeral condyles had a radiolucent line within the center of the condyle, 13 (93%) had radiographic signs of degenerative joint disease and an abnormal medial coronoid process, and six (43%) had periosteal proliferation involving the lateral epicondyle. Examination of biopsy samples from the fracture sites of two cocker spaniels showed fibrous tissue present at the fracture surfaces. The results of this study suggest an association between incomplete ossification of the humeral condyle in cocker spaniels and Brittany spaniels and a high prevalence of HCFs. Eight affected cocker spaniels with available pedigree information were found to be genetically related, suggesting that incomplete ossification of the humeral condyle may be a genetic disease with a recessive mode of inheritance.  相似文献   
225.
A technique for hepatobiliary scanning in horses in described. The images acquired were also analyzed by computer, and the normal temporal parameters of the study were described for both fasted and fed horses. No significant differences were found between fasted and fed animals. Maximum activity in the liver was reached within 10 minutes in all cases, and reached 50% of maximum by 36.2 ± 13.8 minutes in fasted horses, and 26.2 ± 4.5 minutes in fed horses. Maximum activity within the bile duct was reached by 14.6 ± 4.2 minutes in fed horses and 18.0 ± 5.7 minutes in fasted horses. The time after injection to 50% of maximum was 30.4 ± 7.1 minutes in fasted horses and 21.0 ± 5.4 minutes in fed horses. This technique shows promise for the evaluation of equine patients with hepatobiliary disease.  相似文献   
226.
Phillip F.  Steyn  BSc  BVSc  MRCVS  David  Schmitz  DVM  MS  Jeffrey  Watkins  DVM  MS  Jay  Hoffman  BS  DVM 《Veterinary radiology & ultrasound》1989,30(3):125-127
Chronic proliferative synovitis is an insidious condition affecting the metacarpophalangeal joints of horses. It results in proliferation of the synovium in the dorsal pouch of the joint in question. Treatment involves surgical excision, thus confirmation of the lesion is important. Classically this has been achieved by means of positive-contrast arthrography, but this article addresses the attributes of ultrasonography, a less invasive imaging technique.  相似文献   
227.
The abilities of pulmonary angiography, digital subtraction angiography and ventilation-perfusion scintigraphy (V/Q) to detect experimental acute pulmonary emboli were evaluated in a group of 18 research dogs. Emboli were produced by forceful intravenous injection of clotted blood. In five dogs, emboli were labeled with thallium-201 prior to reinjection so that embolus position could be confirmed on scintigraphic studies.
Studies were independently reviewed by three observers. Results were combined so that the relative sensitivity, specificity, and accuracy of each imaging technique could be compared using chi-square and receiver-operating characteristic curve analysis. Digital subtraction angiography and V/Q studies proved to be significantly more specific and accurate than conventional pulmonary angiography. V/Q studies were uniformly of good to excellent quality while the quality of digital subtraction angiography studies was variable depending on the adverse effects of respiratory motion. It was concluded that ventilation-perfusion scintigraphy is the best available method to screen dogs suspected of having pulmonary thromboembolism.  相似文献   
228.
Drug-induced splenic congestion has been reported in dogs secondary to barbiturate administration. This research attempted to verify and quantify size changes associated with drug-induced splenic congestion in dogs. Transverse plane ultrasound images of the spleen in normal dogs were collected to determine the maximum diameter in the minimum dimension prior to, and 15 min after, administration of acepromazine, thiopental, or propofol. Significant splenic enlargement was seen after administration of acepromazine (P<0.01) and thiopental (P=0.02), but no enlargement was seen after administration of propofol. Significantly increased attenuation (P<0.01) and a trend of increased backscatter (P=0.09) were measured after administration of acepromazine. These results indicate that measurable splenomegaly occurs after acepromazine and thiopental administration. This represents the first report of a condition causing measurable diffuse increased attenuation in the spleen. Propofol does not cause measurable splenic enlargement under the conditions of this research.  相似文献   
229.
R.T. O''Brien  DVM  MS    M. Iani  DVM    J. Matheson  DVM    F. Delaney  BS    K. Young  VMD  PhD 《Veterinary radiology & ultrasound》2004,45(6):547-553
Thirty-two dogs with spontaneous hepatic nodules were given intravenous ultrasound contrast medium (Definity or Sonovue) and imaged with contrast harmonic software on a conventional ultrasound machine system. Digital video images were initially reviewed to describe the perfusion pattern of malignant nodules. The images were reviewed again to test this pattern against all individual nodules. Subjectively, there was improved conspicuity of malignant nodules after contrast enhancement compared with conventional imaging and increased numbers of malignant nodules were often noted. There was decreased conspicuity of benign nodules and no additional nodules were seen after contrast enhancement. There was a highly significant (P < 0.0001) association of malignancy with a hypoechoic nodule at surrounding normal liver peak contrast enhancement. Benign nodules were isoechoic to the surrounding normal liver at peak contrast enhancement. Only one benign nodule (hepatoma) had regions of hypoechogenicity compared with the surrounding normal liver at peak liver contrast enhancement. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were highly significant (P < 0.0001) (100%, 94.1%, 93.8%, 100%, and 96.9%, respectively). No complications or morbidity was noted throughout the course of the study. Contrast harmonic ultrasound appears to be accurate at discriminating between naturally occurring benign and malignant nodules in the liver of dogs.  相似文献   
230.
Objective: The purpose of this study was to determine the effect of timing of analysis, collection tube type and repeated opening of sample tubes on venous PCO2, pH, HCO3, and base excess (BE) results. Design: Prospective experimental study, paired sample analysis. Setting: Veterinary Medical Teaching Hospital. Animals: Twenty dogs. Interventions: Jugular venous blood samples. Measurements and main results: PCO2, pH, HCO3, and BE were determined immediately following collection (control) and at selected times up to 30 minutes after placement in either screw top or vacuum heparin collection tubes. A different set of screw top and vacuum heparin collection tubes were sampled repeatedly over time for up to 15 minutes. In the screw top delayed analysis group, only pH changed significantly at one time point. PCO2 decreased significantly in all other groups and resulted in a significant reciprocal pH change in the vacuum tubes with either delayed single analysis or repeated sampling. HCO3 and BE declined significantly in multi‐sampled vacuum tubes and HCO3 also decreased significantly in multi‐sampled screw top tubes. Conclusions: Analysis of acid–base status is optimally performed on freshly drawn blood. However, when it is anticipated there will be a delay in analysis of samples kept at room temperature, the use of 2.0 mL plastic screw top heparin anticoagulant tubes may result in fewer pre‐analytical errors than 3.5 mL glass vacuum tubes.  相似文献   
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