全文获取类型
收费全文 | 1517篇 |
免费 | 54篇 |
国内免费 | 77篇 |
专业分类
林业 | 141篇 |
农学 | 230篇 |
基础科学 | 51篇 |
346篇 | |
综合类 | 255篇 |
农作物 | 89篇 |
水产渔业 | 50篇 |
畜牧兽医 | 359篇 |
园艺 | 41篇 |
植物保护 | 86篇 |
出版年
2022年 | 40篇 |
2021年 | 39篇 |
2020年 | 35篇 |
2019年 | 23篇 |
2018年 | 20篇 |
2017年 | 32篇 |
2016年 | 34篇 |
2015年 | 35篇 |
2014年 | 25篇 |
2013年 | 92篇 |
2012年 | 69篇 |
2011年 | 74篇 |
2010年 | 71篇 |
2009年 | 58篇 |
2008年 | 72篇 |
2007年 | 65篇 |
2006年 | 70篇 |
2005年 | 69篇 |
2004年 | 26篇 |
2003年 | 34篇 |
2002年 | 36篇 |
2001年 | 40篇 |
2000年 | 38篇 |
1999年 | 42篇 |
1998年 | 28篇 |
1997年 | 39篇 |
1996年 | 31篇 |
1995年 | 17篇 |
1994年 | 17篇 |
1993年 | 13篇 |
1992年 | 16篇 |
1991年 | 18篇 |
1990年 | 21篇 |
1989年 | 15篇 |
1988年 | 18篇 |
1987年 | 18篇 |
1985年 | 13篇 |
1983年 | 12篇 |
1979年 | 23篇 |
1978年 | 8篇 |
1977年 | 9篇 |
1976年 | 11篇 |
1975年 | 8篇 |
1971年 | 21篇 |
1970年 | 14篇 |
1969年 | 14篇 |
1968年 | 8篇 |
1967年 | 20篇 |
1966年 | 21篇 |
1965年 | 10篇 |
排序方式: 共有1648条查询结果,搜索用时 15 毫秒
21.
22.
23.
24.
25.
26.
A rapid MTT colorimetric assay to assess the proliferative index of two Indian strains of Theileria annulata 总被引:3,自引:0,他引:3
Saravanan BC Sreekumar C Bansal GC Ray D Rao JR Mishra AK 《Veterinary parasitology》2003,113(3-4):211-216
A study was undertaken to compare the proliferative index of macroschizont-infected lymphoblastoid cells of two Indian strains [Izatnagar (IZT) and Parbhani (PBN)] of Theileria annulata by an in vitro MTT [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide], colorimetric assay. Culture conditions were standardized to define the optimal cell concentration in 96-well microculture plates to yield nearly 100% living cells for measurement of the metabolized formazan activity. A cell concentration of 1.5x10(5) cells/ml was found to be optimal for effective discrimination of the parasite strains. On the basis of conversion of MTT by the actively proliferating lymphoblastoid cells, the PBN strain of T. annulata stimulated a 2.5-fold increase in formazan activity in comparison to the IZT strain. The in vitro MTT assay was found to be a simple and convenient method for assessing the cell activation rate and growth, obviating the need for radioactive material for the assay. The results of the proliferation assay are discussed in relation to previously documented information on the biological characteristics of this important pathogen of cattle. 相似文献
27.
28.
运用建立的质量控制图,监控不同实验条件对布鲁氏菌试管凝集实验结果可能造成的影响。在每次日常检测时对标准阳性血清进行试管凝集实验并使用浊度仪测量其上清液的光密度(OD值),在收集足够有效数据后,绘制当前条件下的质量控制图。通过模拟日常实验条件下孵育温度、时间等容易产生偏离的条件,记录不同实验条件下标准阳性血清试管凝集实验后上清液的OD值,绘制控制用控制图。运用绘制的质量控制图对不同实验条件进行监控,发现孵育温度和孵育时间均对实验结果产生较大影响,从而导致失控。采用质量控制图对布鲁氏菌试管凝集实验进行监控,可提高质量监控的有效性、科学性。严格控制实验条件是保证实验结果的重要前提。 相似文献
29.
Rao GS Ramesh S Ahmad AH Tripathi HC Sharma LD Malik JK 《Veterinary research communications》2001,25(3):197-204
The pharmacokinetics of enrofloxacin and its active metabolite ciprofloxacin were investigated in goats after a single intramuscular administration of enrofloxacin at 2.5 mg/kg body weight. The plasma concentrations of enrofloxacin and ciprofloxacin were determined simultaneously by a HPLC method. The peak concentrations (C
max) of enrofloxacin (1.13 g/ml) and ciprofloxacin (0.24 g/ml) were observed at 0.8 and 1.2 h, respectively. The elimination half-life (t
1/2), volume of distribution (V
d(area)), total body clearance (ClB) and mean residence time (MRT) of enrofloxacin were 0.74 h, 1.42 L/kg, 1329 ml/h per kg and 1.54 h, respectively. The t
1/2, area under the plasma concentration–time curve (AUC) and the MRT of ciprofloxacin were 1.38 h, 0.74 g h/ml and 2.73 h, respectively. The metabolic conversion of enrofloxacin to ciprofloxacin was appreciable (36%) and the sum of the plasma concentrations of enrofloxacin and ciprofloxacin was maintained at or above 0.1 g/ml for up to 4 h. Enrofloxacin appears to be useful for the treatment of goat diseases associated with pathogens sensitive to this drug. 相似文献
30.
Campylobacter 总被引:5,自引:0,他引:5
Moore JE Corcoran D Dooley JS Fanning S Lucey B Matsuda M McDowell DA Mégraud F Millar BC O'Mahony R O'Riordan L O'Rourke M Rao JR Rooney PJ Sails A Whyte P 《Veterinary research》2005,36(3):351-382
Species within the genus, Campylobacter, have emerged over the last three decades as significant clinical pathogens, particularly of human public health concern, where the majority of acute bacterial enteritis in the Western world is due to these organisms. Of particular concern are the species, C. jejuni and C. coli, which are responsible for most of these gastrointestinal-related infections. Although these organisms have already emerged as causative agents of zoonoses, several aspects of their epidemiology and pathophysiology are only beginning to emerge. Trends in increasing antibiotic resistance are beginning to emerge with oral antibiotics, which may be the drug of choice for when it is necessary to intervene chemotherapeutically. This review wishes to examine (i) emerging clinical aspects of the disease, such as Guillain Barre syndrome (GBS), (ii) the association between these organisms and poultry as a natural host, (iii) environmental aspects of Campylobacter epidemiology, (iv) the emergence of atypical campylobacters (v) emerging trends in antibiotic resistance, (vi) adoption of modern methods for the detection of campylobacters. 相似文献