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41.
CASE DESCRIPTION: A 3-year-old Thoroughbred mare was evaluated because of abnormal upper respiratory tract sounds (that had become apparent during race training) of 3 to 4 months' duration. CLINICAL FINDINGS: On initial physical evaluation, there were no abnormal findings. During trotting, an abnormal upper airway expiratory sound was audible. Endoscopic examination revealed a small mass protruding into the right ventral nasal meatus. Radiographic images of the skull revealed no abnormal findings. Computed tomography of the head revealed an abnormal structure in the same location as the mass that was observed during endoscopy. The x-ray attenuation of the mass was identical to that of dental tissue. TREATMENT AND OUTCOME: The mass was surgically removed with endoscopic guidance. On gross examination, the excised mass appeared to be a nearly normal molariform tooth. Histologic examination revealed that it was a well-formed tooth, with no other associated cellular populations. The mass was determined to be a molariform supernumerary intranasal tooth. Six months following discharge from the hospital, the trainer reported that the abnormal respiratory tract sound was no longer audible. During a follow-up endoscopic examination performed at the training facility, no abnormalities were detected. CLINICAL RELEVANCE: In horses, an intranasal tooth should be considered as a differential diagnosis for expiratory stridor. Clear definitions of heterotopic polyodontia, dentigerous cyst, and temporal teratoma can be used to clinically diagnose these separate anomalies. In the horse of this report, computed tomographic findings contributed to determination of a diagnosis and formulation of a treatment plan.  相似文献   
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BACKGROUND: Infection is an infrequent but major complication of cardiovascular device implantation. HYPOTHESIS: Treatment of patients with cardiovascular implant infection with antibiotic therapy and removal of the device is superior to antibiotic therapy alone. METHODS: Medical records were reviewed for dogs that received a cardiovascular device from June 2001 to August 2006 at the University of Minnesota Veterinary Medical Center and the University of Missouri Veterinary Medical Teaching Hospital. RESULTS: Six of 63 (9.5%) pacemaker systems and 2 of 47 (4.3%) patent ductus arteriosus (PDA) occlusion devices became infected. Median time from procedure to diagnosis of implant infection was 62 days (range, 5 to 419). Median age of dogs with pacemaker infections was 8.5 years (range, 6.2 to 11.9). Pseudomonas aeruginosa and Staphylococcus spp were the most commonly cultured isolates. Four dogs were treated with antibiotics and pacemaker replacement. All 4 recovered completely from their infections. One was alive at the end of the study period, and 3 had been euthanized. However, the reasons for euthanasia were unrelated to pacemaker infection. In contrast, both dogs with infected pacemakers that were treated with antibiotics alone were euthanized because of complications attributable to infection. Infection of PDA occlusion devices occurred in puppies < 16 weeks of age, and Pasteurella spp were isolated from both. One was successfully treated with a combination of antibiotics and surgery, and the other was euthanized without treatment. CONCLUSIONS AND CLINICAL IMPORTANCE: Antibiotic therapy alone is associated with chronic complications in patients with cardiovascular implants and is unlikely to effect a cure.  相似文献   
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An enzymatic end-point method for the quantitative determination of L-arginine was evaluated with samples of synthetic wine and natural grape juice. The enzymes arginase, urease, and glutamate dehydrogenase were used in this simple assay, similar to those described for many metabolites by Boehringer-Mannheim. In synthetic wine, recovery of L-arginine ranged between 98.3 and 104.4% and the precision as coefficient of variation was between 0.4 and 1.47% in the concentration range of the method, 0-100 mg/L L-arginine. The recovery of L-arginine in a grape juice with added L-arginine after clarification with polyvinylpolypyrrolidone ranged between 100 and 101.3%, and the coefficient of variation was 0.6%. The method has low material costs of approximately 0.43 U.S.$ per assay, and the time course of the reaction facilitates measurement of several samples concurrently. The results of this evaluation indicate that the enzymatic assay is a preferred method over colorimetric methods for the manual determination of L-arginine.  相似文献   
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The capability of organic wastes to release available N in soil varies largely, depending on their source and form of production, or rather on their composition and biodegradability. Our purpose was to predict mineralization rates of different materials using their analyses joined with a simulation model, and to evaluate the influence of soil type and application rate of the organic materials on N and C transformations in soil. Four organic materials, sewage sludge (SS), sewage sludge compost (SSC), cattle manure compost (CMC), hen and cattle manure compost (HCMC), were applied to two soils at rates of 2 and/or 4%. The soils were incubated aerobically for 168 days at 30°C, during which CO2 evolution rates and mineral-N concentrations were measured periodically. Hot water extractable C and N of all organic amendments correlated well with short term C and N mineralization, except HCMC that immobilized N although its soluble N content was large. NCSOIL, a computer model that simulates C and N cycling in soil with organic amendments, predicted well C and N mineralization of SS, SSC and CMC when considered as three-pool materials that decomposed at specific rates of 0.4, 0.024 and 10?4 d?1, using hot water soluble C and N as the labile pool. N immobilization by HCMC could be simulated only if the distribution of N between the labile and resistant pools was derived by optimization of NCSOIL, while hot water soluble C was labile. Laboratory methods to determine an intermediate pool or components that contribute to immobilization are required for improving the predictions of C and N mineralization from organic amendments.  相似文献   
46.
The demand for novel effective antioxidant-based drugs has led to the synthesis and evaluation of the antioxidant potential in several molecules derived from natural compounds. In this work the in vitro antioxidant activity of an abietic acid-derived catechol (methyl 11,12-dihydroxyabietate-8,11,13-trien-18-oate, MDTO) was evaluated. This substance, possessing important biological properties, is similar to carnosic acid, a natural antioxidant from rosemary or sage leaves. Aiming to understand the antioxidant activity of MDTO, the energetics of its O-H bond, using time-resolved photoacoustic calorimetry (TR-PAC), was investigated. On energetic grounds it is predicted that MDTO is a good free radical scavenger, although its activity is lower than that of quercetin, a very effective antioxidant, which was used for comparison. In agreement with these predictions, the DPPH(*) and ABTS(*+) radical scavenging activities are lower than those of quercetin. In addition, MDTO also reacts with HOCl, a powerful proinflammatory oxidant produced by activated neutrophils, and protects liposomes against iron-ascorbate-induced oxidation. The discussion of these results foresees potential applications of MDTO as an antioxidant.  相似文献   
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Background

Doxorubicin is a common antineoplastic agent with dose‐dependent cardiotoxic adverse effects, and pre‐existing myocardial dysfunction is a contraindication to its use.

Objectives

To systematically define the hemodynamic and biochemical alterations in dogs undergoing chemotherapy for newly diagnosed lymphoma and assess the reversibility of these alterations with fluid administration.

Animals

Twenty‐one client‐owned dogs with newly diagnosed lymphoma were evaluated 1 week after induction of chemotherapy. Underlying degenerative valve disease was exclusionary. Eighteen healthy age‐ and weight‐matched dogs were used as controls.

Methods

Physical examination, blood pressure by Doppler, echocardiography, and biochemical evaluation (routine serum biochemistry, plasma renin activity and aldosterone concentrations, plasma and urine osmolalities, and urine electrolyte concentrations) were measured in dogs with lymphoma and compared to controls. Dogs with lymphoma received crystalloids IV at 6 mL/kg/h for 24 hours. All variables were reassessed at 4 and 24 hours. Deuterium oxide dilution and bromide dilution were used to determine total body water and extracellular water space, respectively.

Results

Baseline echocardiograms showed significantly smaller chamber dimensions in dogs with lymphoma compared to controls. These changes were reversed by fluid administration. Systolic blood pressure and urine sodium concentration were significantly increased, and bromide dilution space, PCV, urine specific gravity, and urine potassium concentration were significantly decreased compared to controls.

Conclusion and Clinical Importance

Echocardiographic and biochemical abnormalities in dogs with lymphoma appear consistent with volume depletion, and may be the result of systemic hypertension and subsequent pressure natriuresis.  相似文献   
50.
The effects of a pomegranate byproduct (PBP, which includes the whole pomegranate fruit left after juice preparation) on atherosclerosis development in apolipoprotein E-deficient (E degrees ) mice were studied. Consumption of PBP (17 or 51.5 microg of gallic acid equiv/kg/day) by the mice resulted in a significant reduction in atherosclerotic lesion size by up to 57%. PBP consumption significantly reduced oxidative stress in the mice peritoneal macrophages (MPM): Cellular lipid peroxide content decreased by up to 42%, the reduced glutathione levels increased by up to 53%, and paraoxonase 2 lactonase activity increased by up to 50%, as compared to MPM from E degrees mice that consumed only water. Furthermore, oxidized low-density lipoprotein (Ox-LDL) uptake by the MPM was reduced by up to 19%. Similar results were observed also in vitro. Treatment of J774A.1 macrophages with PBP (10 or 50 micromol/L of total polyphenols) significantly decreased both cellular total peroxide content and Ox-LDL uptake. It was thus concluded that PBP significantly attenuates atherosclerosis development by its antioxidant properties.  相似文献   
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