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   207篇
  免费   14篇
林业   15篇
农学   3篇
  40篇
综合类   11篇
农作物   7篇
水产渔业   13篇
畜牧兽医   114篇
园艺   4篇
植物保护   14篇
  2023年   6篇
  2022年   5篇
  2021年   10篇
  2020年   13篇
  2019年   11篇
  2018年   5篇
  2017年   9篇
  2016年   14篇
  2015年   6篇
  2014年   15篇
  2013年   16篇
  2012年   23篇
  2011年   15篇
  2010年   13篇
  2009年   5篇
  2008年   8篇
  2007年   11篇
  2006年   5篇
  2005年   10篇
  2004年   9篇
  2003年   4篇
  2002年   6篇
  1996年   1篇
  1988年   1篇
排序方式: 共有221条查询结果,搜索用时 31 毫秒
161.
Therapy of canine mammary tumours (CMTs) with classical antitumour drugs is problematic, so better therapeutic options are needed. Palbociclib (PD‐0332991) is an innovative and effective anticancer drug for the treatment of breast cancer in women. Palbociclib is an inhibitor of cyclin‐dependent kinase 4 (CDK4) and CDK6, which are key regulators of the cell cycle machinery and thus cell proliferation. In the present in vitro study, we investigated whether Palbociclib also represents a candidate drug to combat CMT. For this purpose, the effect of Palbociclib was analysed in P114 and CF41 cells, two CMT cell lines with an endogenous CDK4/6 co‐expression. Incubation of P114 and CF41 cells with Palbociclib resulted in a dose‐ and time‐dependent loss of phosphorylated retinoblastoma protein (pRb), a classical CDK4/6 substrate within the cell cycle machinery. Moreover, treatment of CMT cells with Palbociclib‐induced cell cycle arrest affected cell viability, prevented colony formation and impaired cell migration activity. Palbociclib also inhibited the growth of P114 and CF41 cell spheroids. Immunohistochemical analysis of canine patient samples revealed a consistent expression of CDK6 in different canine mammary carcinoma types, but an individual and tumour‐specific expression pattern of phosphorylated pRb independent of the tumour grade. Together, our findings let us suggest that Palbociclib has antitumour effects on CMT cells and that canine patients may represent potential candidates for treatment with this CDK4/6 inhibitor.  相似文献   
162.
A 12-year-old female dog with a 3-month history of poor response to diabetes treatment had an acute worsening of symptoms, including weakness and blindness. The dog had elevated blood glucose, alkaline phosphatase and urea concentration, hyposthenuria, glycosuria, hematuria, and pyuria. Escherichia coli was isolated from the urine. Radiographs and ultrasound examination showed that the dog had unilateral emphysematous pyelitis and concurrent cystitis associated with vesicoureteral reflux.  相似文献   
163.
164.
Canine pituitary hyperadrenocorticism (Cushing's disease) caused by neoplasia of the corticotrope cells is one of the most common endocrine diseases especially in smaller dog breeds. Cushing's disease was diagnosed in eleven wire-haired Dachshunds and for further six wire-haired Dachshunds Cushing's disease was suspected on the basis of clinical signs. A joined pedigree could be ascertained for all these 17 dogs. Eleven of these dogs were so closely related to each other, that they were summarized in four nucleus families. Two fullsiblings were examined by means of clinical, laboratory diagnostic and morphological methods. The main lesions consisted of atrophic dermatosis with alopecia, increase of activity of liver enzymes in plasma and bilateral adrenocortical hyperplasia and therefore corresponded to the typical signs of a secondary hyperadrenocorticism. A rather unusual finding was the pituitary carcinoma in one of these dogs. Similarly to human patients affected by hyperadrenocorticism, real-time PCR analysis showed a 2.9-fold increase of expression of the canine MDR1 gene in the liver of one affected wirehaired Dachshund. This study documents the first familial occurrence of pituitary-dependent hyperadrenocorticism in wirehaired Dachshunds, the overexpression of the MDR1 gene in the dog and the third case of familial hyperadrenocorticism in dogs ever described.  相似文献   
165.
166.
167.
Nidularium minutum Mez is a terrestrial bromeliad with ornamental potential, especially as a species that develops the shade. This, as well as many other bromeliads, is endangered. We studied the growth of nitrogen (N). N. minutum cultured in vitro in different concentrations of nitrogen (N), phosphorus (P), potassium (K), or calcium (Ca) to develop an ideal growth environment for this plant to preserve the species. Results favorable to the growth were treatments containing 60 mM N, 0.60 and 1.25 mM P, 10 mM K, and 1.5 mM Ca. Based on these results two new culture media were prepared (T1 and T2) and were compared with the MS medium with dilutions of macronutrients (50%, 20%, 10%, and 5%). The results showed that changes in the MS medium favored growth of N. minutum.  相似文献   
168.
The aim of this study was to use preselected quality indicators for Litopenaeus vannamei post-larvae and the stable isotopes technique with δ13C and δ15N to determine the influence of bioflocs in shrimp feeding during the nursery phase, between PL1 and PL30. A control treatment (CT) with water renewal was compared to a biofloc treatment (BT) that received organic carbon fertilizations. Different types of commercial feed (Stresspak and Flake-INVE?, PL40-GUABI?), microalgae (Chaetoceros muelleri) and Artemia sp. nauplii were used as food sources. The physical and chemical parameters of water and ammonia were monitored daily, and nitrite, nitrate and alkalinity were measured weekly. Suspended solids and the microorganisms of bioflocs were characterized. At the end of the experiment, fifteen shrimps of each replicate were collected to evaluate nine larvae quality indicators. Isotopic values of 13C and 15N of food sources and shrimp tissues were collected on days 10, 20 and 30, and a Bayesian model of isotopic mixture measured the contributions of these sources to the shrimp biomass. Salinity, alkalinity and nitrite differed significantly between the treatments but were appropriate for post-larvae production. The larvae quality conditions in the CT treatment were ranked as “good,” whereas the BT conditions were considered “excellent” according to the analysis of larval quality parameters. The stable isotopes analysis showed that the PL40 GUABI? feed was the most important food source throughout the experimental period in the CT. In the BT (10th and 20th days), the bioflocs and commercial feeds (Flake-INVE?, PL40-GUABI?) did not present significant variations in their contribution ratios; however, on the 30th day, the contribution of the PL40-GUABI? feed was higher when compared to bioflocs. In general, the commercial feed played a more important role as a food source for Litopenaeus vannamei larvae during the nursery phase, although the consumption of bioflocs led to a better larvae quality.  相似文献   
169.
This report describes a rare case of squamous cell carcinoma invading the right temporomandibular joint, right guttural pouch, and calvarium. Radiography, computed tomography, and histopathology were performed in the diagnostic workup. Computed tomography depicted more accurately than radiography the invasive nature, exact location, and extent of the lesion.  相似文献   
170.
Despite the dangerousness of the dry wood-boring beetle Trichoferus holosericeus (Rossi) (=Hesperophanes cinereus (Villiers)) (Coleoptera: Cerambycidae), little is known about its biological and nutritional requirements. The aim of this research was therefore to investigate into the dietary preferences of this insect, in order to determine if carbohydrates can be considered as its main nutritional source, to clarify whether this cerambycid is specialised on hardwoods and finally to select a suitable diet for laboratory cultures. Different substrates were tested and the decay grade, as well as the survival of larvae, was recorded after 3 and 6 months. Chemical analyses were also carried out on excrements, residues of wood after larvae excavation and sound wood. Results indicated that T. holosericeus fed mainly on glucose and peptone added to an artificial diet, while on natural wood it preferred structural carbohydrates constituting the hemicelluloses and the non-crystalline cellulose. Furthermore, Scots pine sapwood had no toxic effect to the beetle. In terms of number and dimensions of emerged larvae, the artificial diet resulted to be the most suitable substrate for laboratory cultures of T. holosericeus among those tested.  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