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   197篇
  免费   20篇
  国内免费   7篇
基础科学   1篇
  1篇
综合类   12篇
农作物   3篇
水产渔业   22篇
畜牧兽医   163篇
园艺   4篇
植物保护   18篇
  2022年   8篇
  2021年   6篇
  2020年   4篇
  2019年   9篇
  2018年   6篇
  2017年   11篇
  2016年   9篇
  2015年   11篇
  2014年   8篇
  2013年   15篇
  2012年   11篇
  2011年   14篇
  2010年   13篇
  2009年   12篇
  2008年   7篇
  2007年   13篇
  2006年   5篇
  2005年   6篇
  2004年   3篇
  2003年   4篇
  2002年   5篇
  2001年   5篇
  2000年   3篇
  1999年   1篇
  1998年   4篇
  1997年   2篇
  1995年   2篇
  1994年   1篇
  1993年   3篇
  1991年   1篇
  1990年   3篇
  1989年   1篇
  1986年   1篇
  1985年   2篇
  1984年   1篇
  1983年   1篇
  1982年   4篇
  1981年   1篇
  1979年   2篇
  1978年   1篇
  1977年   1篇
  1974年   2篇
  1973年   1篇
  1956年   1篇
排序方式: 共有224条查询结果,搜索用时 546 毫秒
221.
AIM:To investigate the possible protective effect of sequoyitol on type 2 diabetic rats with liver inflammatory lesions. METHODS:Type 2 diabetic rats were induced by feeding high-fat/high-sugar diet and injecting with a low dose of streptozotocin. Sequoyitol at doses of 12.5, 25 and 50 mg·kg-1·d-1 was orally administered in the model rats. At the end of the experiment, the rats were sacrificed. Serum levels of fasting blood glucose, alanine aminotransferase(ALT), aspartate aminotransferase(AST) and albumin(ALB) were determined. Liver wet was recorded and liver index was calculated. The levels of C-reactive protein(CRP),tumor necrosis factor α(TNF-α) and interleukin 6(IL-6) in the liver tissues were also measured. Real-time PCR was used to determine the mRNA expression of TNF-α. In addition, the pathological changes of the liver were observed with HE staining. RESULTS:Compared with the model rats, treatment with sequoyitol obviously decreased the levels of fasting blood glucose, ALT, AST, ALB, CRP, TNF-α and IL-6, reduced the liver index, down-regulated the mRNA expression of TNF-α in the liver, and ameliorated the pathologic changes of the liver. CONCLUSION:Sequoyitol attenuates liver lesions in type 2 diabetic rats through down-regulation of TNF-α and IL-6 expression.  相似文献   
222.
Reasons for performing study: Subchondral bone provides structural support to overlying articular cartilage and plays an important biomechanical role in osteochondral diseases. Mechanical features of bone correlate strongly with bone mineral density, which is directed by the loading conditions to which the tissue is subjected. Objective: To investigate the influence of physical activity levels on subchondral bone mineral density (sBMD) in foals during early development. Methods: Three groups of foals were subjected to different physical activity levels from birth until age 5 months. A proportion of these foals were subjected to euthanasia at 5 months while remaining foals were subjected to similar physical activity levels for 6 months until euthanasia at 11 months. Osteochondral specimens were collected for measurement of sBMD with peripheral quantitative computed tomography at 2 differently loaded anatomical sites of the proximal phalangeal bone at 1, 2, 3, 4 and 5 mm depth from the osteochondral junction. Results: Growth significantly increased sBMD but by a different amount depending on anatomical location and physical activity level. Significantly higher sBMD was found at the habitually loaded central area in comparison to the intermittently peak loaded marginal site. Exercise increased sBMD throughout the whole depth of analysed tissue, but changes were generally more obvious at a depth of 2 mm. Interestingly, foals subjected to additional sprint training preserved the exercise‐induced sBMD increase at the habitually loaded central area during the 6 months of the second phase of the study. Conclusions: Habitual low‐intensity loading elicits a greater response in sBMD in quantitative terms than high‐intensity low‐frequency loading at the sites investigated in this study. Future sBMD may be influenced by means of well‐tailored exercise regimens at young age. Potential relevance: Specific physical activity levels during early development may potentially reduce the prevalence of osteochondral injury later in life.  相似文献   
223.
A 15-y-old castrated male Maine Coon cat was evaluated for an ulcerated soft tissue mass on the right hindlimb that had been observed for 4 mo and had grown rapidly. A 3 × 3 cm soft, raised, amorphous, and ulcerated subcutaneous mass was observed on the lateral right metatarsus. In-house cytology via fine-needle aspiration was nondiagnostic. Incisional biopsy of the mass and further staging was declined, and amputation was elected. The amputated limb was submitted for histopathology, which revealed severe chronic nodular granulomatous dermatitis and multifocal granulomatous popliteal lymphadenitis with large numbers of intralesional fungal hyphae. Fungal PCR and sequencing on formalin-fixed, paraffin-embedded tissue identified Chalastospora gossypii. No adjunctive therapy was elected at the time. The patient has done well clinically 1 y post-operatively. C. gossypii is a rare microfungus found worldwide and is considered a minor pathogen of several plants. To our knowledge, infection by this fungus has not been reported previously in veterinary species. Features in our case are comparable to other mycotic infections. Nodular granulomatous mycotic dermatitis and cellulitis, although uncommon, should be a differential for soft tissue masses in veterinary species; C. gossypii is a novel isolate.  相似文献   
224.
自2001年欧盟实施疯牛病主动监测以后,人们发现一种新的与典型疯牛病不一样的疯牛病,即非典型疯牛病。后来,在日本、加拿大、美国、巴西等也发现非典型疯牛病。目前普遍认为,该类疯牛病多发于老年牛,临床上有的表现症状,有的无症状,具有自发性和散发性特征,发病率低,约为百万分之一至百万分之三。研究发现,非典型疯牛病可以分为H型和L型,两者在PK酶抗性、糖基化、传染性、机体内分布等存在差异,同时与典型疯牛病也存在明显差异。比较来看,L型疯牛病的传染性最强,H型疯牛病的传染性较弱。论文从非典型疯牛病的临床症状、病理变化、病原分布及分子特性、传染性等方面做了详细介绍。  相似文献   
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