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   83篇
  免费   3篇
林业   4篇
农学   9篇
  1篇
综合类   4篇
农作物   1篇
水产渔业   9篇
畜牧兽医   53篇
园艺   1篇
植物保护   4篇
  2023年   1篇
  2022年   5篇
  2021年   4篇
  2020年   4篇
  2019年   3篇
  2018年   3篇
  2016年   1篇
  2015年   6篇
  2014年   1篇
  2013年   5篇
  2012年   3篇
  2011年   3篇
  2008年   3篇
  2007年   3篇
  2006年   2篇
  2005年   1篇
  2004年   6篇
  2003年   2篇
  2002年   2篇
  2001年   6篇
  2000年   4篇
  1999年   4篇
  1998年   3篇
  1997年   1篇
  1996年   2篇
  1995年   1篇
  1991年   3篇
  1988年   1篇
  1986年   1篇
  1985年   1篇
  1963年   1篇
排序方式: 共有86条查询结果,搜索用时 15 毫秒
1.
2.
The present study aimed to quantitatively evaluate muscle mass and gene expression in dogs with glucocorticoid-induced muscle atrophy. Five healthy beagles received oral prednisolone for 4 weeks (1 mg/kg/day), and muscle mass was then evaluated via computed tomography. Histological and gene expression analyses were performed using biopsy samples from the biceps femoris before and after prednisolone administration. The cross-sectional area of the third lumbar paraspinal and mid-femoral muscles significantly decreased after glucocorticoid administration (from 27.5 ± 1.9 to 22.6 ± 2.0 cm2 and from 55.1 ± 4.7 to 50.7 ± 4.1 cm2, respectively; P<0.01). The fast- and slow-twitch muscle fibers were both atrophied (from 2,779 ± 369 to 1,581 ± 207 μm2 and from 2,871 ± 211 to 1,971 ± 169 μm2, respectively; P<0.05). The expression of the growth factor receptor-bound protein 10 (GRB10) significantly increased after prednisolone administration (P<0.05). Because GRB10 suppresses insulin signaling and the subsequent mammalian target of rapamycin complex 1 activity, increased expression of GRB10 may have resulted in a decrease in protein anabolism. Taken together, 1 mg/kg/day oral prednisolone for 4 weeks induced significant muscle atrophy in dogs, and GRB10 might participate in the pathology of glucocorticoid-induced muscle atrophy in canines.  相似文献   
3.
Most scientific attention on port studies centers on deep sea ports, especially container ports. In this paper, in contrast, attention is focused on the spatial–temporal development of inland waterway ports on the Midstream Yangtze River from 2001 to 2013. The aim of this study is to assess two relevant and complementary questions of the hinterland evolution: its geographical extent and the coordination relationship with the inland port. To conduct the study, it was necessary to first identify the boundaries of the ports' hinterlands within the given timeframe. Then, the coupling coordination degree model was introduced to explore the underlying relationship between the port service and hinterland economy. Furthermore, to better depict the intricate economic characteristics of the hinterland, the development stage theory was applied in the models. The results highlight the emergence of a discontinuous hinterland at Wuhan Port and its reinforcement of primacy with respect to fierce hinterland rivalry. It also demonstrates that an interplay between major ports and their corresponding hinterlands evolves from the transitional stage, characterized by lagging port service, to the multi‐stage, wherein the supply of ports partly outstrips hinterland demand.  相似文献   
4.
Spiramycin (SP), oxytetracycline (OTC) or sulphamonomethoxine (SMM) was fed to laying hens at a dietary level of 400 p.p.m. for 7 successive days. After 7 days of medicated feed, the concentrations of SP, OTC and SMM were determined in the blood, liver, ovary, oviducts (magnum and isthmus plus shell gland) and eggs (albumen and yolk) by high-performance liquid chromatography. Of the three drugs, OTC showed the lowest content in the above tissues and eggs, while the reverse was true for SMM. Low concentrations of SP were measured in the blood, whereas contents in the liver and the oviducts were relatively much higher.  相似文献   
5.
Immune system is organized by the influence of both neural and endocrine systems. NK activity plays an important role in the innate immunity. In this study, we observed the effects of restraint stress on chicken peripheral blood NK activity. Viability of FITC-labeled RP9 was measured with PI after treatment with the effector cells. Chicken peripheral blood CD8alpha+ cells expressed strong cytotoxic activity, in contrast to thrombocytes, while peripheral blood CD3+ CD8alpha+ cells and CD4+ cells had little cytotoxic activity. Con A supernatant enhanced the cytotoxic activity of CD8alpha+ cells. Therefore, it is considered that these cytotoxic activities measured by flow cytometry (FCM) analysis are NK activity. When chickens were exposed to restraint stress, the levels of serum corticosterone increased transiently over a short period of time while the NK activity decreased. The decreased NK activity, however, did not recover to the intact levels for a long time, even once the serum corticosterone levels had recovered. These data indicate that chicken NK activity is able to be measured by flow cytometric analysis and that restraint stress causes severe damage to the chicken NK activity.  相似文献   
6.
In vitro protein binding of spiramycin (SP) in the plasma and oviducts of laying hens was studied. The data for SP were compared with those for oxytetracycline (OTC), sulphadimidine (SDD), sulphamonomethoxine (SMM) and sulphaquinoxaline (SQ). The two oviduct segments, magnum (M) and isthmus plus shell gland (IS), were collected. The soluble (cell sap) fractions from the magnum (M-S9) and the isthmus plus shell gland (IS-S9) were used as samples. Plasma protein binding was highest for SQ (81.4%) (P < 0.01), and lowest for SDD (30.9%) (P < 0.01). No M-S9 protein binding of OTC was found. The IS-S9 protein binding of SP (60.4%) was very much higher than those of OTC (0.8%), SDD (4.1%), SMM (4.0%) and SQ (12.3%) (P < 0.01). Biological half-lives of these drugs in egg albumen were directly correlated to the extent of their binding to IS proteins. Of plasma, M-S9 and IS-S9, variation in SP concentration in the ranges from 1 to 20 micrograms/ml did not alter the binding properties of the drug.  相似文献   
7.
The aim of this study was to evaluate the prognostic value of concurrent measurement of serum phosphorylated neurofilament heavy subunit (pNF-H) concentration and intramedullary T2W hyperintensity in paraplegic to paraplegic dogs. Our hypothesis was that concurrent measurement of these would provide a more accurate prediction of functional outcome in dogs with thoracolumbar intervertebral disc herniation (IVDH). A prospective case-control clinical study was designed using 94 dogs with acute onset of thoracolumbar IVDH. The association of serum pNF-H concentration, T2W hyperintensity on sagittal MRI (T2H/L2), deep pain perception and surgical outcome were evaluated with logistic regression analysis after three months for all 94 surgically treated dogs. Sensitivity to predict non-ambulatory outcome was compared among pNF-H and T2H/L2 and combination of both. Logistic regression analysis indicated that serum pNF-H concentration and T2H/L2 were significantly correlated with surgical outcome (P<0.05); however, deep pain perception was not (P=0.41). The results of logistic regression analysis indicated that the odds ratios of unsuccessful long-term outcome were 2.6 for serum pNF-H concentration, 1.9 for T2H/L2 and 2.3 for deep pain sensation. The sensitivity and specificity to predict non-ambulatory outcome for using serum parameter pNF-H>2.6 ng/ml, using T2H/L2 value of>0.84 and using both serum pNF-H and T2H/L2, were 95% and 75.7%, 65% and 86.5%, and 90.0% and 97.5%, respectively. Therefore, combined measurements of serum pNF-H and T2H/L2 might be useful for predicting long-term outcome in dogs with thoracolumbar IVDH.  相似文献   
8.
9.
10.
ABSTRACT:   High- and multi-frequency acoustic measurement systems and the multi-frequency inversion (MFI) method have been used to measure spatial distributions and abundances of zooplankton by size. In this study, the calibration method for high- and multi-frequency systems was developed and the validation of MFI method was carried out by scatterer measurement. The standard sphere calibration method that has not been applied to such high- and multi-frequencies was applied to calibrate our high- and multi-frequency system, TAPS-6 (Tracor Acoustic Profiling System, BAE Systems). An optimum size of standard sphere of tungsten carbide of 1 mm radius was derived to have a small target strength variation for the six frequencies of TAPS-6, and the practicability and precision of the standard sphere calibration method was confirmed for those frequencies. A school or cluster of dummy scatterers of zooplankton with small tungsten carbide spheres were designed to validate the MFI method, and volume back-scattering strength values were measured by the multi-frequency system. By comparing the result of the inversion with their real composition, the features of the MFI method could be validated and examined.  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