全文获取类型
收费全文 | 1177篇 |
免费 | 127篇 |
国内免费 | 1篇 |
出版年
2023年 | 5篇 |
2022年 | 15篇 |
2021年 | 27篇 |
2020年 | 17篇 |
2019年 | 15篇 |
2018年 | 16篇 |
2017年 | 24篇 |
2016年 | 46篇 |
2015年 | 70篇 |
2014年 | 68篇 |
2013年 | 72篇 |
2012年 | 91篇 |
2011年 | 86篇 |
2010年 | 52篇 |
2009年 | 46篇 |
2008年 | 82篇 |
2007年 | 69篇 |
2006年 | 48篇 |
2005年 | 45篇 |
2004年 | 60篇 |
2003年 | 51篇 |
2002年 | 38篇 |
2001年 | 15篇 |
2000年 | 8篇 |
1999年 | 18篇 |
1998年 | 8篇 |
1997年 | 12篇 |
1996年 | 8篇 |
1993年 | 8篇 |
1992年 | 8篇 |
1991年 | 6篇 |
1990年 | 11篇 |
1989年 | 7篇 |
1988年 | 6篇 |
1984年 | 4篇 |
1983年 | 4篇 |
1982年 | 7篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1978年 | 8篇 |
1977年 | 5篇 |
1976年 | 5篇 |
1975年 | 7篇 |
1974年 | 5篇 |
1973年 | 7篇 |
1969年 | 5篇 |
1968年 | 7篇 |
1967年 | 6篇 |
1962年 | 6篇 |
1960年 | 4篇 |
排序方式: 共有1305条查询结果,搜索用时 31 毫秒
991.
M. K. Tolba D. I. C. Ph. D. Josephine K. Eskarous M. Sc. Ph. D. 《Archives of microbiology》1959,34(4):333-338
Summary The strains of fowl-plague virus being tested completely lost their infectivity to chick embryos when stored at pH 4 for one hour or more while those of the virus of Newcastle disease were all infective to chick embryos when stored at this pH-value for periods up to 7 days. 相似文献
992.
Josephine Jo Danna 《Culture, medicine and psychiatry》1980,4(1):25-42
Interpretations of studies which show a correlation between migration and mental illness generally focus on sociocultural variables while giving scant attention to determinants of cognitive-personality orientations. This article examines childhood socialization practices as a key variable for comparing points of psychological stress between the traditional rural culture and the post-industrial urban culture. The hypothesis that harsh and restrictive childhood socialization practices foster the development of a cognitivepersonality orientation which increases the likelihood of maladaptive responses to culture change is illustrated by anthropological and psychological data obtained from Sicilians living in Sicily, the U.S.A. and Australia. Suggestions are given for minimizing the mental health risks involved during the critical transition period following migration. 相似文献
993.
Josephine Barnes 《BMJ (Clinical research ed.)》1980,280(6229):1424
994.
Takao Tsuji Shunkun Yao Josephine Encarnacion Joya Takeshi Honda Toshio Miwatani 《FEMS microbiology letters》1989,61(1-2):1-6
Abstract We purified heat-labile enterotoxins (LThs) from YT3, H-10407 and YT240 strains isolated from human diarrheal patients. These LThs were immunologically identical to each other. The molecular weights of their A and B subunits were also the same by means of SDS-polyacrylamide gel electrophoresis. However, the ionic charges of the molecular surfaces of these LThs were different as shown by polyacrylamide gel isoelectric focusing. Though the p I points of B subunits of the LThs were identical to each other, the p I points of A subunits were found to be different. These data suggest that the ionic charge differences among A subunits cause differences in holo LThs in their charge, and that there is heterogeneity among A subunits produced by strains of human enterotoxigenic Escherichia coli . 相似文献
995.
E N Wardle 《BMJ (Clinical research ed.)》1976,2(6038):755-756
996.
Josephine Barnes 《BMJ (Clinical research ed.)》1944,1(4332):79-80
997.
Michael J. Gundale Jennie Sverker Benedicte R. Albrectsen Marie-Charlotte Nilsson David A. Wardle 《Plant Ecology》2010,211(2):253-266
We investigated among and within species variation in several litter chemical properties, including protein complexation capacity
(PCC), for six plant species across a boreal forest chronosequence in northern Sweden across which stand fertility declines
sharply with stand age. We hypothesized (1) that evergreen species which dominate in late-successional stands would exhibit
higher PCCs than deciduous species that dominate in young stands, (2) that individual species would increase their PCCs in
response to nutrient limitation as succession proceeds, and (3) that differences in PCC among litter types would determine
their interactive effects with proteins on soil N and C mineralization. The data demonstrated a high PCC, but a low PCC per
unit of soluble phenol, for two deciduous species that dominate in early-successional high fertility stands, providing mixed
support for our first hypothesis. No species demonstrated a significant correlation between their PCC and stand age, which
did not support our second hypothesis. Finally, a soil incubation assay revealed that litter extracts for three of the six
species had negative interactive effects with added proteins on N mineralization rates, and that all six species demonstrated
positive interactive effects with protein on C mineralization. This pattern did not provide strong support for our third hypothesis,
and suggests that N immobilization was likely a more important factor regulating N mineralization than stabilization of proteins
into tannin complexes. These data suggest that multiple interactive mechanisms between litter extracts and proteins likely
occur simultaneously to influence the availability of N in soils. 相似文献
998.
999.
Julie Gauzere Josephine M. Pemberton Sean Morris Alison Morris Loeske E. B. Kruuk Craig A. Walling 《Evolution; international journal of organic evolution》2020,74(7):1378-1391
Maternal effects, either environmental or genetic in origin, are an underappreciated source of phenotypic variance in natural populations. Maternal genetic effects have the potential to constrain or enhance the evolution of offspring traits depending on their magnitude and their genetic correlation with direct genetic effects. We estimated the maternal effect variance and its genetic component for 12 traits expressed over the life history in a pedigreed population of wild red deer (morphology, survival/longevity, breeding success). We only found support for maternal genetic effect variance in the two neonatal morphological traits: birth weight ( = 0.31) and birth leg length ( = 0.17). For these two traits, the genetic correlation between maternal and direct additive effects was not significantly different from zero, indicating no constraint to evolution from genetic architecture. In contrast, variance in maternal genetic effects enhanced the additive genetic variance available to respond to natural selection. Maternal effect variance was negligible for late-life traits. We found no evidence for sex differences in either the direct or maternal genetic architecture of offspring traits. Our results suggest that maternal genetic effect variance declines over the lifetime, but also that this additional heritable genetic variation may facilitate evolutionary responses of early-life traits. 相似文献
1000.
Betageri R Gilmore T Kuzmich D Kirrane TM Bentzien J Wiedenmayer D Bekkali Y Regan J Berry A Latli B Kukulka AJ Fadra TN Nelson RM Goldrick S Zuvela-Jelaska L Souza D Pelletier J Dinallo R Panzenbeck M Torcellini C Lee H Pack E Harcken C Nabozny G Thomson DS 《Bioorganic & medicinal chemistry letters》2011,21(22):6842-6851
We report a SAR of non-steroidal glucocorticoid mimetics that utilize indoles as A-ring mimetics. Detailed SAR is discussed with a focus on improving PR and MR selectivity, GR agonism, and in vitro dissociation profile. SAR analysis led to compound (R)-33 which showed high PR and MR selectivity, potent agonist activity, and reduced transactivation activity in the MMTV and aromatase assays. The compound is equipotent to prednisolone in the LPS-TNF model of inflammation. In mouse CIA, at 30 mg/kg compound (R)-33 inhibited disease progression with an efficacy similar to the 3 mg/kg dose of prednisolone. 相似文献