全文获取类型
收费全文 | 780篇 |
免费 | 72篇 |
专业分类
852篇 |
出版年
2023年 | 6篇 |
2022年 | 8篇 |
2021年 | 14篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 14篇 |
2017年 | 12篇 |
2016年 | 14篇 |
2015年 | 32篇 |
2014年 | 35篇 |
2013年 | 37篇 |
2012年 | 60篇 |
2011年 | 56篇 |
2010年 | 31篇 |
2009年 | 29篇 |
2008年 | 34篇 |
2007年 | 45篇 |
2006年 | 55篇 |
2005年 | 46篇 |
2004年 | 57篇 |
2003年 | 38篇 |
2002年 | 33篇 |
2001年 | 13篇 |
2000年 | 8篇 |
1999年 | 11篇 |
1998年 | 6篇 |
1997年 | 12篇 |
1996年 | 9篇 |
1995年 | 9篇 |
1994年 | 3篇 |
1993年 | 8篇 |
1992年 | 10篇 |
1991年 | 12篇 |
1990年 | 8篇 |
1989年 | 7篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1984年 | 7篇 |
1983年 | 4篇 |
1982年 | 5篇 |
1981年 | 7篇 |
1980年 | 3篇 |
1979年 | 6篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1976年 | 3篇 |
1974年 | 3篇 |
1973年 | 2篇 |
1971年 | 2篇 |
1960年 | 2篇 |
排序方式: 共有852条查询结果,搜索用时 15 毫秒
841.
Victor Plourde Helen C. Wong John H. Walsh Helen E. Raybould Yvette Tach 《Peptides》1993,14(6):1225-1229
The role of capsaicin-sensitive pathways and CGRP in postoperative gastric ileus was investigated. Abdominal surgery was performed under enflurane anesthesia, and 5 min later, the 20-min rate of gastric emptying was measured by the phenol red method in conscious rats. Surgery inhibited gastric emptying by 76–83% compared with rats receiving anesthesia alone. Capsaicin on the celiac/mesenteric ganglia (10–21 days before) reduced gastric ileus by 33 ± 8%, whereas perivagal capsaicin had no effect. The IV CGRP-induced inhibition of gastric emptying was completely reversed by the CGRP antagonist, CGRP(8–37) (30 μg, IV); CGRP(8–37) (15, 30, or 60 μg) or CGRP monoclonal antibody #4901 (2 mg protein) decreased the inhibition of gastric emptying by 11 ± 7%, 51 ± 13%, 47 ± 3%, and 45 ± 17%, respectively. These results indicate that CGRP and splanchnic capsaicin-sensitive afferents are involved in mediating part of the gastric ileus observed immediately after abdominal surgery. 相似文献
842.
We developed a simulation study to test the efficiency of genomic selection (GS) in the case of Eucalyptus breeding. We simulated a recurrent selection scheme for clone production over four breeding cycles. Scenarios crossing broad sense heritabilities (H 2?=?0.6 and 0.1) and dominance to additive variance ratios (R?=?0.1; 0.5; and 1) were compared. GS was performed with 1,000 SNPs and 22 QTLs per Morgan and tested against phenotypic selection (PS) based on best linear unbiased prediction of parents and clones. When the training population was made up of the first cycle progeny tests and the candidate populations were the progeny tests of three successive cycles, GS accuracy decreased with breeding cycles (e.g., from 0.9 to 0.4 with H 2?=?0.6 and R?=?0.1), whereas PS presented constant performances (accuracy of 0.8 with H 2?=?0.6 and R?=?0.1). When the training population set was updated by associating data of previous cycles, GS accuracy was improved from 25 % to 418 %, especially with H 2?=?0.1. The GS model including dominance effects performed better in clone selection (genotypic value) when dominance effects were preponderant (R?=?1), heritability was high (H 2?=?0.6 and with an updated training set), but no improvement was detected for parent selection (breeding value). The genetic gains over cycles were lower with the GS method without updating the data set but, with an updated training set, were similar to PS. However, the genetic gain per unit time with GS was 1.5 to 3 times higher than with PS for breeding and clone populations. These results highlight the value of GS in Eucalyptus breeding. 相似文献
843.
844.
845.
Yvette Charriere-Ladreix 《Phytochemistry》1975,14(8):1727-1731
By using the normal techniques of protein separation, two forms of PAL with different properties have been separated from the glandular tissue of Aesculus hippocastanum. A hypothesis is proposed for correlating the isoenzyme activities with the accumulation of flavonoid compounds and benzoic acids in the trichomes. 相似文献
846.
847.
Bouvet Jean Francois; Godinot Florette; Croze Sylviane; Delaleu Jean Claude 《Chemical senses》1987,12(3):499-505
The location and distribution of nerve fibres displaying substanceP (SP) immunoreactivity were studied in the frog olfactory mucosa.Many immunoreactive nerve fibres were noted in close associationwith Bowman's glands and blood vessels in the lamina propria.In addition, such fibres were also found beneath and withinthe olfactory epithelium proper. These fibres are clearly oftrigeminal origin since SP immunoreactivity was abolished aftersection of the trigeminal nerve. Functionally, they might influencelocal blood flow, secretion of Bowman's glands and/or activityof olfactory receptor cells. 相似文献
848.
849.
850.