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BACKGROUND: Management of strawberry powdery mildew, Podopshaera aphanis (Wallr.), requires numerous fungicide treatments. Limiting epidemics is heavily dependent on sterol demethylation inhibitors (DMIs) such as myclobutanil or penconazole. Recently, a noticeable reduction in the efficacy of these triazole fungicides was reported by strawberry growers in France. The goal of this study was to investigate the state of DMI sensitivity of French P. aphanis and provide tools for improved pest management. RESULTS: Using leaf disc sporulation assays, sensitivity to myclobutanil and penconazole of 23 isolates of P. aphanis was monitored. Myclobutanil EC50 ranged from less than 0.1 to 14.67 mg L?1 and for penconazole from 0.04 to 4.2 mg L?1. A cross‐analysis and a Venn diagram showed that there was reduced sensitivity and a positive correlation between the less sensitive myclobutanil and penconazole isolates; 73.9% of isolates were less sensitive to a DMI and 47.8% exhibited less sensitivity to both fungicides. CONCLUSION: The results show that sensitivity to myclobutanil and, to a lesser extent, penconazole has become less efficient in strawberry powdery mildew in France. Therefore, urgent action is required in order to document its appearance and optimise methods of control. Copyright © 2009 Society of Chemical Industry  相似文献   
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The long pentraxin 3 (PTX3) plays an important role in host defence and its over-expression may contribute to airway injury. The aim of the present study was therefore to characterize in more detail PTX3 and its expression in the horses’ airway. Six healthy horses and six horses affected by recurrent airway obstruction (R.A.O.) were submitted to a dusty environment challenge. PTX3 DNA and cDNA were cloned and sequenced. PTX3 expression was evaluated by RT-qPCR, Western blotting and immuno-histochemistry in bronchoalveolar lavage fluid (BALF) cells, BALF supernatant and bronchial epithelial cells. An alternative splicing of the second exon of PTX3 occurred, resulting in two forms of the protein: “spliced” (32 kDa) and “full length” (42 kDa). PTX3 was detected in BALF macrophages, neutrophils and bronchial epithelial cells. It was over-expressed in the BALF supernatant from R.A.O.-affected horses in crisis. However, dust was unable to induce PTX3 in BALF cells ex vivo, indicating that dust is an indirect inducer of PTX3. Dust exposure in-vivo induced PTX3 in BALF macrophages but there was no significant difference between healthy and R.A.O.-affected horses. Conversely, PTX3 was over-expressed in the bronchial epithelial cells from R.A.O.-affected horses in crisis. These data indicate a differential regulatory mechanism in inflammatory and bronchial epithelial cells and offer therapeutically interesting perspectives.  相似文献   
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OBJECTIVE: To evaluate the effects of positioning and number of repeated measurements on intra- and interobserver variability of echocardiographic measurements in dogs. DESIGN: Prospective study. ANIMALS: 4 healthy dogs. PROCEDURE: Each observer performed 24 examinations, separately assessing each dog 6 nonconsecutive times (3 times with the dog in lateral recumbency and 3 with the dog in a standing position). Variables evaluated included M-mode measurements of left ventricular end-diastolic and left ventricular end-systolic diameters, left ventricular free-wall thickness in diastole and systole, interventricular septal thickness in diastole and systole, left ventricular shortening fraction, and 2-dimensional measurements of the left atrial diameter-to-aortic diameter ratio. RESULTS: All coefficients of variation (range, 3.4% to 26.6%) were similar between operators and positions and were < 15% for 27 of 32 values. For both operators, repeatability of the measurements was better for left ventricular end-systolic diameter, left ventricular free-wall thickness in diastole, left ventricular free-wall thickness in systole, and the left atrial diameter-to-aortic diameter in the standing position, and similar for both positions for shortening fraction and left ventricular end-diastolic diameter. No effect of cardiac cycle was observed. CONCLUSIONS AND CLINICAL RELEVANCE: Within-day variability of conventional echocardiography performed with the dog in the standing position was at least as good as that obtained with the dog in lateral recumbency for most measured variables. Single measurements of each variable may be sufficient for trained observers examining dogs that do not have an arrhythmia. The standing position should be used, particularly for stressed or dyspneic dogs.  相似文献   
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OBJECTIVE: To determine left ventricular free wall (LVFW) motions and assess their intra- and interday variability via tissue Doppler imaging (TDI) in healthy awake and anesthetized dogs. ANIMALS: 6 healthy adult Beagles. PROCEDURE: n the first part of the study, 72 TDI examinations (36 radial and 36 longitudinal) were performed by the same observer on 4 days during a 2-week period in all dogs. In the second part, 3 dogs were anesthetized with isoflurane and vecuronium. Two measurements of each TDI parameter were made on 2 consecutive cardiac cycles when ventilation was transiently stopped. The TDI parameters included maximal systolic, early, and late diastolic LVFW velocities. RESULTS: The LVFW velocities were significantly higher in the endocardial than in the epicardial layers and also significantly higher in the basal than in the mid-segments in systole, late diastole, and early diastole. The intraday coefficients of variation (CVs) for systole were 16.4% and 22%, and the interday CV values were 11.2% and 16.4% in the endocardial and epicardial layers, respectively. Isoflurane anesthesia significantly improved the intraday CV but induced a decrease in LVFW velocities, except late diastolic in endocardial layers and early diastolic in epicardial layers. CONCLUSIONS AND CLINICAL RELEVANCE: Left ventricular motion can be adequately quantified in dogs and can provide new noninvasive indices of myocardial function. General anesthesia improved repeatability of the procedure but cannot be recommended because it induces a decrease in myocardial velocities.  相似文献   
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An adult male white Bengal tiger (Panthera tigris tigris) with pronounced atrophy of the pelvic musculature was diagnosed with degenerative osteoarthritis of the coxofemoral joints. Initial management with the nonsteroidal anti-inflammatory drug meloxicam and a semisynthetic sodium pentosan polysulfate resulted in clinical improvement and radiographic stabilization of the arthritic condition over several months. However, because pain was still evident, bilateral denervation of the coxofemoral joints was performed, successfully ameliorating the signs of osteoarthritic pain in the tiger. Meloxicam has shown good clinical efficacy for the treatment of osteoarthritis and other painful conditions in large felids. Coxofemoral joint denervation offers many advantages for the treatment of osteoarthritis in exotic carnivore species, and should be considered a viable treatment modality.  相似文献   
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Diffuse large B-cell lymphoma (DLBCL) is frequently treated with chemotherapy incorporating cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP), which induces remission in 80% to 95% of cases. However, not all dogs derive meaningful benefit from CHOP, and prognostic factors for dogs with DLBCL are poorly defined. Serum thymidine kinase 1 (TK1) activity, a marker of tumour cell proliferation, has shown promising initial results as a prognostic biomarker in dogs with multicentric lymphomas. The purpose of this study was to determine if baseline serum TK1 activity is associated with clinical outcome in dogs with CHOP-treated DLBCL. Baseline serum TK1 activity was measured in banked sera from 98 dogs with CHOP-treated DLBCL using a commercially available ELISA kit. Data on other potential prognostic factors were abstracted retrospectively from electronic medical records. Multivariable statistical methods were used to identify associations between TK1 and other potential prognostic factors with progression-free survival (PFS) and attainment of complete remission. TK1 activity at baseline was not associated with PFS (p = .299) or attainment of complete remission (p = .910) following CHOP chemotherapy. Of the other prognostic factors analysed, only purebred (vs. mixed breed) status (HR 8.81, 95% CI 1.68–46.30, p = .010), attainment of complete (vs. partial) remission (HR 0.09, 95% CI 0.02–0.49, p = .006), and baseline serum C-reactive protein concentration (HR 1.19, 95% CI 1.07–1.32, p = .001) were independently associated with PFS. Based on these findings, baseline serum TK1 activity does not appear to be a useful prognostic biomarker in dogs with CHOP-treated DLBCL.  相似文献   
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