首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   216篇
  免费   32篇
林业   3篇
农学   2篇
  20篇
综合类   15篇
农作物   14篇
水产渔业   18篇
畜牧兽医   169篇
园艺   6篇
植物保护   1篇
  2023年   2篇
  2021年   3篇
  2020年   4篇
  2019年   4篇
  2018年   8篇
  2017年   10篇
  2016年   11篇
  2015年   5篇
  2014年   6篇
  2013年   12篇
  2012年   19篇
  2011年   18篇
  2010年   8篇
  2009年   6篇
  2008年   20篇
  2007年   7篇
  2006年   15篇
  2005年   10篇
  2004年   9篇
  2003年   10篇
  2002年   10篇
  2001年   3篇
  2000年   2篇
  1999年   2篇
  1996年   2篇
  1993年   2篇
  1992年   3篇
  1990年   1篇
  1989年   1篇
  1988年   3篇
  1986年   1篇
  1985年   2篇
  1984年   1篇
  1983年   2篇
  1981年   1篇
  1980年   1篇
  1978年   2篇
  1977年   1篇
  1975年   1篇
  1973年   2篇
  1971年   2篇
  1970年   2篇
  1969年   4篇
  1967年   1篇
  1960年   1篇
  1957年   1篇
  1942年   1篇
  1940年   1篇
  1932年   1篇
  1920年   1篇
排序方式: 共有248条查询结果,搜索用时 15 毫秒
81.
Kansas State University implemented a Web-based program to assess students' competency to perform technical skills during clinical rotations throughout the fourth year of the veterinary curriculum. The classes of 2009 and 2010 recorded a minimum number of procedures (104 and 103, respectively) from a menu of more than 220 recommended procedures. Procedures were categorized by species (small animal, equine, food animal) and disciplines (imaging, anesthesia, diagnostic medicine/necropsy). Ophthalmology was added as a fourth discipline for the class of 2010. Students recorded procedures into the Web-based system, including information about the patient, procedure performed, supervisor, and a self-assessment of performance. Faculty, staff, and house officers evaluated the procedures electronically by confirming that they witnessed the procedure and providing qualitative and written feedback. The class of 2009 recorded 18,492 procedures (M=171/student) and the class of 2010 recorded 16,935 procedures (M=158/student). Two students from each class (2009 and 2010) did not complete the minimum required skills during clinical rotations and returned to perform procedures immediately before (n=3) or immediately after (n=1) graduation to receive their diploma. The Web-based system captured a large number of assessments of technical competency performed in the clinical setting. The system provided students with formative feedback throughout the clinical year, ensured equitable distribution of procedural opportunities across the student body, and required minimal additional resources.  相似文献   
82.
We report the earliest recognized fatality associated with laboratory-confirmed pandemic H1N1 (pH1N1) influenza in a domestic cat in the United States. The 12-year old, indoor cat died on 6 November 2009 after exposure to multiple family members who had been ill with influenza-like illness during the peak period of the fall wave of pH1N1 in Pennsylvania during late October 2009. The clinical presentation, history, radiographic, laboratory and necropsy findings are presented to assist veterinary care providers in understanding the features of this disease in cats and the potential for transmission of infection to pets from infected humans.  相似文献   
83.
A mature castrated male domestic shorthair cat was referred for treatment of an excoriated, ulcerated area on the nasal planum. Undifferentiated squamous cell carcinoma was diagnosed. Surgical resection of the nasal planum was not an option, so the lesion was treated 4 times with neodymium:yttrium-aluminum-garnet laser. Laser surgery results in uniform photovaporization of large volumes of tissue. Although treatment with laser does not yield tissue specimens suitable for histologic evaluation, it can result in a cosmetically suitable appearance and can extend the predicted life span. A diagnosis of undifferentiated squamous cell carcinoma has a guarded prognosis: however, the cat of this report survived more than 18 months.  相似文献   
84.
85.
BACKGROUND: Obesity is the most common nutritional disease in dogs. Although weight loss by dietary caloric energy restriction is successful in experimental studies, there is limited information on success of such programs in client-owned dogs who are obese. Further, no information currently exists on the changes in body composition during weight loss in clinical cases. HYPOTHESIS: Key determinants of outcome of weight loss, including energy allocation and body composition, are influenced by both individual and weight program factors. ANIMALS: Nineteen client-owned dogs with naturally occurring obesity. METHODS: In this prospective clinical study, body composition was quantified by dual-energy X-ray absorptiometry before and after weight loss on an individually tailored program that incorporated a high-protein and moderate-fiber diet. RESULTS: Mean percentage weight loss was 18% (range, 6-29%), and mean rate of weight loss was 0.85% per week (range, 0.35-1.56%). Mean energy allocation required to achieve weight loss was 60% of maintenance energy requirement at target weight (MERTW) (range, 50-82%). Significant dietary noncompliance was reported (mean, 1.0% MERTW; range, 0.0-9.5%). The mean composition of tissue lost was 84: 15:1 (fat : lean : bone mineral content [BMC]). Lean tissue loss was positively associated with overall percentage of weight loss (Pearson correlation coefficient [Rp] = 0.591, P = .008), whereas BMC loss was greater in retrievers compared with other breeds (1.9% +/- 1.16% versus 0.8% +/- 0.44%; P = .008). CONCLUSIONS AND CLINICAL IMPORTANCE: This clinical study demonstrated body composition changes during weight loss in dogs. Conventional programs produced safe weight loss, but marked energy restriction was required and the rate of loss was slower than in experimental studies.  相似文献   
86.
A young dog was presented with a history of chronic diarrhea, anorexia, and weight loss. Histoplasma capsulatum was suspected, based on cytologic examination of lymph node aspirates and peritoneal fluid, and confirmed by fungal culture. To our knowledge, this is the first case of histoplasmosis diagnosed in a dog in Atlantic Canada.  相似文献   
87.
A 10‐year‐old, castrated male, German Shepherd mixed‐breed dog was presented to Kansas State University Veterinary Health Center for evaluation of a subconjunctival swelling in the ventral fornix of the left orbit. The owner elected to pursue excision of the mass 2 years after initial consultation following a sudden change in the size and color of the lesion. An excisional biopsy was performed, and the mass along with its associated capsule were submitted to the Comparative Ocular Pathology Laboratory of Wisconsin for histopathologic evaluation, which confirmed the diagnosis of a hibernoma. Fourteen months following excision, the patient showed no evidence of tumor regrowth.  相似文献   
88.
ObjectiveTo evaluate the pharmacokinetics of amitriptyline and its active metabolite nortriptyline after intravenous (IV) and oral amitriptyline administration in healthy dogs.Study designProspective randomized experiment.AnimalsFive healthy Greyhound dogs (three males and two females) aged 2–4 years and weighing 32.5–39.7 kg.MethodsAfter jugular vein catheterization, dogs were administered a single oral or IV dose of amitriptyline (4 mg kg−1). Blood samples were collected at predetermined time points from baseline (0 hours) to 32 hours after administration and plasma concentrations of amitriptyline and nortriptyline were measured by liquid chromatography triple quadrupole mass spectrometry. Non-compartmental pharmacokinetic analyses were performed.ResultsOrally administered amitriptyline was well tolerated, but adverse effects were noted after IV administration. The mean maximum plasma concentration (CMAX) of amitriptyline was 27.4 ng mL−1 at 1 hour and its mean terminal half-life was 4.33 hours following oral amitriptyline. Bioavailability of oral amitriptyline was 6%. The mean CMAX of nortriptyline was 14.4 ng mL−1 at 2.05 hours and its mean terminal half-life was 6.20 hours following oral amitriptyline.Conclusions and clinical relevanceAmitriptyline at 4 mg kg−1 administered orally produced low amitriptyline and nortriptyline plasma concentrations. This brings into question whether the currently recommended oral dose of amitriptyline (1–4 mg kg−1) is appropriate in dogs.  相似文献   
89.
A microbial arsenic cycle in a salt-saturated, extreme environment   总被引:1,自引:0,他引:1  
Searles Lake is a salt-saturated, alkaline brine unusually rich in the toxic element arsenic. Arsenic speciation changed from arsenate [As(V)] to arsenite [As(III)] with sediment depth. Incubated anoxic sediment slurries displayed dissimilatory As(V)-reductase activity that was markedly stimulated by H2 or sulfide, whereas aerobic slurries had rapid As(III)-oxidase activity. An anaerobic, extremely haloalkaliphilic bacterium was isolated from the sediment that grew via As(V) respiration, using either lactate or sulfide as its electron donor. Hence, a full biogeochemical cycle of arsenic occurs in Searles Lake, driven in part by inorganic electron donors.  相似文献   
90.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号