收费全文 | 82993篇 |
免费 | 3901篇 |
国内免费 | 67篇 |
林业 | 4323篇 |
农学 | 2584篇 |
基础科学 | 442篇 |
8867篇 | |
综合类 | 15875篇 |
农作物 | 3624篇 |
水产渔业 | 3802篇 |
畜牧兽医 | 41285篇 |
园艺 | 1090篇 |
植物保护 | 5069篇 |
2018年 | 977篇 |
2017年 | 1102篇 |
2016年 | 1021篇 |
2015年 | 1009篇 |
2014年 | 1157篇 |
2013年 | 2758篇 |
2012年 | 2112篇 |
2011年 | 2386篇 |
2010年 | 1476篇 |
2009年 | 1366篇 |
2008年 | 2125篇 |
2007年 | 2149篇 |
2006年 | 1948篇 |
2005年 | 2595篇 |
2004年 | 2401篇 |
2003年 | 2240篇 |
2002年 | 1819篇 |
2001年 | 2314篇 |
2000年 | 2253篇 |
1999年 | 1955篇 |
1998年 | 709篇 |
1997年 | 701篇 |
1995年 | 821篇 |
1993年 | 705篇 |
1992年 | 1568篇 |
1991年 | 1662篇 |
1990年 | 1779篇 |
1989年 | 1755篇 |
1988年 | 1643篇 |
1987年 | 1555篇 |
1986年 | 1625篇 |
1985年 | 1594篇 |
1984年 | 1316篇 |
1983年 | 1191篇 |
1982年 | 791篇 |
1981年 | 727篇 |
1979年 | 1345篇 |
1978年 | 1057篇 |
1977年 | 907篇 |
1976年 | 857篇 |
1975年 | 1007篇 |
1974年 | 1277篇 |
1973年 | 1318篇 |
1972年 | 1336篇 |
1971年 | 1249篇 |
1970年 | 1146篇 |
1969年 | 1089篇 |
1968年 | 944篇 |
1967年 | 1011篇 |
1966年 | 918篇 |
Objectives
To develop a provisional immunohistochemistry panel for distinguishing reactive pericardium, atypical mesothelial proliferation and mesothelioma in dogs.Materials and Methods
Archived pericardial biopsies were subject to haematoxylin and eosin staining, immunohistochemistry for cytokeratin, vimentin, insulin‐like growth factor II mRNA‐binding protein 3, glucose transporter 1 and desmin. Samples were scored for intensity and number of cells stained.Results
Ten biopsies of reactive mesothelium, 17 of atypical mesothelial proliferation, 26 of mesothelioma and five of normal pericardium were identified on the basis of haematoxylin and eosin staining. Cytokeratin and vimentin were expressed in all biopsies, confirming mesothelial origin. Normal pericardial samples had the lowest scores for insulin‐like growth factor II mRNA‐binding protein 3, glucose transporter 1 and desmin. Mesothelioma and atypical proliferative samples were similar to each other, with higher scores for insulin‐like growth factor II mRNA‐binding protein 3 and glucose transporter 1 than the reactive samples. Desmin staining was variable. Insulin‐like growth factor II mRNA‐binding protein 3 was the best to distinguish between disease groups.Clinical Significance
An immunohistochemistry panel of cytokeratin, vimentin, insulin‐like growth factor II mRNA‐binding protein 3 and glucose transporter 1 could provide superior information compared with haematoxylin and eosin staining alone in the diagnosis of cases of mesothelial proliferation in canine pericardium, but further validation is warranted. 相似文献2. Ten dietary treatments were offered to 6 replicate cages (6 birds per cage) of male Ross 308 chickens from 7 to 28 d post-hatch. The effects of treatment on relative gizzard weights, gizzard contents, pancreatic weights and pH of gizzard digesta were monitored. Parameters of growth performance, nutrient utilisation (apparent metabolisable energy [AME], metabolisable to gross energy [ME:GE] ratios, nitrogen [N] retention and N-corrected AME [AMEn]), apparent starch and protein (N) digestibility coefficients and disappearance rates in for small intestinal segments and concentrations of free amino acids in plasma taken from the anterior mesenteric vein were determined.
3. Whole grain feeding (WGF) did not influence weight gain, but 30% post-pellet blended and 15 and 30% post-pellet separated treatments significantly depressed (P < 0.05) feed intakes while the 30% post-pellet separated treatment improved (P < 0.01) feed conversion ratios (FCR). WGF regimes significantly increased relative gizzard weights.
4. Overall, WGF generated profound responses in AME, ME:GE ratios, N retention and AMEn that were highly correlated with relative gizzard weights. In general, WGF improved starch and protein (N) digestibilities and again there were some correlations with these outcomes and relative gizzard weights.
5. Post-pellet WG inclusions where WG and pelleted concentrate were offered separately provided chickens with the opportunity to choice feed. Birds showed a preference for the relatively high-protein pelleted concentrate and at 30% WG, this resulted in an improvement in FCR of 7.69% (1.260 versus 1.365; P < 0.001) relative to the ground-grain control diet. 相似文献