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551.
Flunixin meglumine has been reported to induce gastrointestinal lesions in dogs when administered at therapeutic dosages. We administered flunixin meglumine to dogs daily for 10 days to assess the effect of this drug on the gastrointestinal tract. We also evaluated the possibility of corticosteroid potentiation of gastrointestinal toxicosis by concurrent administration of prednisone to 1 group of dogs. Dogs were monitored for gastrointestinal toxicosis by means of serial endoscopic evaluation, measurement of fecal occult blood, PCV, and total solid concentration, and by physical examination. There were 3 treatment groups of 5 dogs each. Group-1 dogs were given 2.2 mg of flunixin meglumine/kg daily, in 2 divided doses IM; group-2 dogs were given 4.4 mg of flunixin meglumine/kg daily, in 2 divided doses IM; and group-3 dogs were given 2.2 mg of flunixin meglumine/kg daily, in 2 divided doses IM plus 1.1 mg of prednisone/kg/d orally, in 2 divided doses. A fourth group of 5 dogs served as a control group. Endoscopically visible gastric mucosal lesions developed in all treated dogs within 4 days of initiating treatment. Lesions first developed in the gastric pylorus and antrum and lesions at these sites were more severe than those observed elsewhere. Dogs treated with flunixin meglumine plus prednisone developed the earliest and most severe lesions; lesion scores in group-2 dogs were higher than those in group-1 dogs. All dogs treated had occult blood in their feces by day 5 and its presence appeared to correlate more closely with endoscopic findings than did physical examination findings or changes in values for PCV or total solids.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
552.
高温蘑菇浙Ag HWZ—1生物学特性的研究   总被引:1,自引:1,他引:0  
浙Ag HWZ-1是一株性状与大肥茹(Agaricus bitorquis)相似,风味近似于双孢蘑菇(A.bisporus)的高温四孢蘑菇菌株。出菇适宜温度为27~30℃,菌丝生长温度18~34℃,最适为27℃,为至今国内报道的出菇温度最高的蘑菇菌株。PH值范围为4~9,最近为6。基质(棉籽壳)最适含水量为60~66%。菌丝在黑暗下生长良好,光照对菌丝生长具抑制作用,高浓度CO_2可促进菌丝生长,子实体纽结和发育仅需很少的新鲜空气。菌株对碳源利用以麦芽糖为优,淀粉、乳糖和甲基纤维素较差;有机氮比无机氮更有利于菌丝生长,以酵母粉最优,尿素最差。菌丝在供试的三种基质上均能生长,在麦粒上生长最快。  相似文献   
553.
554.
Background: Continuous administration of low doses of cyclophosphamide and standard doses of cyclooxygenase‐inhibiting drugs has been shown to suppress tumor angiogenesis, reverse immunosuppression, and deplete regulatory T cells in cancer models. Hypothesis: We hypothesized that continuous treatment with low‐dose cyclophosphamide and full‐dose piroxicam would delay tumor recurrence in dogs with soft tissue sarcomas (STS). Animals: Eighty‐five dogs with incompletely resected STS, 30 treated dogs, and 55 contemporary control dogs. Methods: Treatment outcomes in 85 dogs with incompletely resected STS were evaluated in a retrospective study. Dogs in the treatment group received continuously administered low‐dose cyclophosphamide (10 mg/m2) and standard dose piroxicam (0.3 mg/kg) therapy. Time to local tumor recurrence (disease‐free interval; DFI) was compared between the 30 treated dogs and 55 untreated control dogs matched for age and tumor site and grade. Results: DFI was significantly (P < .0001) prolonged for STS of all sites (trunk and extremity) in treated dogs compared with untreated control dogs. The DFI also was significantly longer in treated dogs when tumor site (trunk and extremity) was compared. Twelve treated dogs (40%) experienced mild toxicity (grade 1 and 2) at some point during treatment and 1 dog developed grade 4 cystitis. Every other day dosing was tolerated better than daily dosing. Conclusions: Metronomic therapy with cyclophosphamide and piroxicam was very effective in preventing tumor recurrence in dogs with incompletely resected STS. These findings suggest that further evaluation of this approach is warranted as adjuvant therapy in dogs with highly metastatic tumors such as osteosarcoma and melanoma.  相似文献   
555.
BACKGROUND: Flow cytometry has been used to detect anti-red blood cell (RBC) antibodies in dogs with immune-mediated hemolytic anemia (IMHA), but the prevalence of anti-RBC antibodies in anemic and nonanemic dogs with a variety of different diseases has not been assessed previously. HYPOTHESIS: We hypothesized that anti-RBC antibodies would be more common in anemic dogs and in dogs with immune-mediated disorders and cancer. ANIMALS: Blood samples from 292 dogs were analyzed prospectively by flow cytometry for anti-RBC antibodies. METHODS: Blood samples from 147 anemic and 145 nonanemic dogs were evaluated by flow cytometry to detect surface-bound immunoglobulin (Ig) G and IgM antibodies on RBC. Disease associations with RBC antibodies were determined, as was the correlation between disease status and the percentage of Ig(+) RBC. The specificity and sensitivity of flow cytometry and clinical variables for the diagnosis of IMHA were compared by Bayesian analysis. RESULTS: Anemic dogs were significantly more likely to be positive for anti-RBC antibodies (IgG, IgM, or both) than nonanemic dogs. Anemic dogs also had significantly higher percentages of Ig(+) RBC than nonanemic dogs, whereas dogs with IMHA had significantly higher percentages of Ig(+) RBC than dogs with all other diseases. Dogs with IMHA, infectious diseases, and immune-mediated thrombocytopenia were significantly more likely to have anti-RBC antibodies than dogs with other medical or surgical diseases. CONCLUSIONS: Anemic dogs with immune-mediated diseases and infectious diseases were at the highest risk for the development of anti-RBC antibodies, and flow cytometry for the detection of IgG on RBC was highly sensitive and specific for the diagnosis of IMHA.  相似文献   
556.
557.
Objective— To evaluate 4 methods of cholecystostomy catheter placement and to report on laparoscopic (Lap) cholecystostomy for the management of extrahepatic biliary obstruction (EHBO) in 3 dogs.
Study Design— Experimental study and clinical report.
Animals— Cadaveric dogs (n=20); 2 canine and 1 feline patient.
Methods— Pigtail cholecystostomy catheters were inserted in 20 canine cadavers using ultrasound (US) or Lap guidance. Insertion routes were either transperitoneal or transhepatic. Methods studied included Lap-transperitoneal, US-transperitoneal, US-transhepatic, and US-Seldinger (n=5 dogs/group). Insertion success, pleural penetration, and insertion site leakage (Lap-transperitoneal group) were evaluated. Three clinical EHBO cases were treated by Lap-transperitoneal technique.
Results— Insertion success was 100% by Lap-transperitoneal but 0% with US-transperitoneal and US-Seldinger methods. US-transhepatic yielded 3 of 5 successful placements. The pleura was penetrated in all US-transhepatic and US-Seldinger insertions. Leakage pressure for Lap-transperitoneal catheters averaged 75 cm H2O (±20 cm H2O). Lap-transperitoneal cholecystostomy resulted in marked improvement in 2 dogs, but the catheter became obstructed in the cat. One dog spontaneously regained common bile duct patency and the remaining 2 animals had successful cholecystoenterostomy.
Conclusions— In cadaver testing, the Lap-transperitoneal cholecystostomy method was superior based on high insertion success with no pleural penetration. In 2 clinical cases, Lap-transperitoneal placement successfully provided biliary drainage for patient stabilization.
Clinical Relevance— The role for temporary cholecystostomy has yet to be established, but may aid patient stabilization and mortality reduction in EHBO.  相似文献   
558.
559.
The influence of pH and iota-carrageenan concentration on the properties of beta-lactoglobulin (beta-Lg)-stabilized oil-in-water emulsions was investigated by measuring the particle charge, particle size distribution, and creaming stability. Emulsions containing droplets stabilized by beta-Lg were produced by homogenization, and then, iota-carrageenan was added. At pH 3, the droplet charge did not change for iota-carrageenan concentrations 相似文献   
560.
Isothermal titration calorimetry (ITC) was used to study interactions between an anionic surfactant (sodium dodecyl sulfate, SDS) and maltodextrins with different dextrose equivalents (DE) in a buffer solution (pH 7.0, 10 mM NaCl, 20 mM Trizma, 30.0 degrees C). The interaction between SDS and maltodextrin was exothermic, which was attributed to incorporation of the hydrocarbon tail of the surfactant into a helical coil formed by the maltodextrin molecules. ITC measurements indicated that the number of SDS molecules bound per gram of maltodextrin increased with decreasing maltodextrin DE, i.e., increasing molecular weight. It was proposed that SDS only binds to maltodextrin molecules that have a DE greater than 10 glucose units.  相似文献   
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