全文获取类型
收费全文 | 330篇 |
免费 | 30篇 |
国内免费 | 1篇 |
出版年
2023年 | 4篇 |
2022年 | 4篇 |
2021年 | 7篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 13篇 |
2017年 | 6篇 |
2016年 | 11篇 |
2015年 | 11篇 |
2014年 | 12篇 |
2013年 | 14篇 |
2012年 | 27篇 |
2011年 | 31篇 |
2010年 | 19篇 |
2009年 | 15篇 |
2008年 | 20篇 |
2007年 | 11篇 |
2006年 | 19篇 |
2005年 | 12篇 |
2004年 | 11篇 |
2003年 | 16篇 |
2002年 | 13篇 |
2001年 | 15篇 |
2000年 | 12篇 |
1999年 | 8篇 |
1998年 | 1篇 |
1997年 | 5篇 |
1996年 | 6篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1990年 | 6篇 |
1989年 | 4篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1979年 | 2篇 |
1970年 | 1篇 |
排序方式: 共有361条查询结果,搜索用时 31 毫秒
71.
Summary The composition and synthesis of DNA in synchronous cultures of Chlorella pyrenoidosa strain 211/8b has been investigated. Analytical CsCl density gradient centrifugation gave a homogenous major DNA component with a (G+C) content of 51% and a minor component containing 28% (G+C). The (G+C) contents derived from melting profiles were 2–3% lower. A second minor component with approximately 41% (G+C) content was inferred from banding patterns of labelled DNA in preparative CsCl density gradients.
14C-uracil was readily incorporated into the pyrimidine moieties of the major (nuclear) DNA between the 10th and 18th hour after beginning of the light period, but not at any other time. 14C-uracil incorporation into the minor (satellite) component was low but continuous throughout the whole cell cycle. The incorporation is correlated with an increase in the proportion of satellite DNA from 6% up to 20% during the time when no nuclear DNA replication takes place. The results suggest that different regulatory mechanisms exist for the nuclear and for satellite DNA synthesis. 相似文献
72.
Thorbald van Hall Claudia C. Oliveira Simone A. Joosten Tom H.M. Ottenhoff 《Microbes and infection / Institut Pasteur》2010,12(12-13):910-918
The non-polymorphic MHC molecule Qa-1 and its human counterpart HLA-E present monomorphic signal peptides to innate receptors and thereby regulate lymphocyte activity. Under stress, this peptide content is replaced with a surprisingly diverse repertoire of novel peptides that are associated with heat-shock proteins, infectious agents or antigen processing defects. 相似文献
73.
S Dinkla K Wessels W P R Verdurmen C Tomelleri J C A Cluitmans J Fransen B Fuchs J Schiller I Joosten R Brock G J C G M Bosman 《Cell death & disease》2012,3(10):e410
Inflammation enhances the secretion of sphingomyelinases (SMases). SMases catalyze the hydrolysis of sphingomyelin into phosphocholine and ceramide. In erythrocytes, ceramide formation leads to exposure of the removal signal phosphatidylserine (PS), creating a potential link between SMase activity and anemia of inflammation. Therefore, we studied the effects of SMase on various pathophysiologically relevant parameters of erythrocyte homeostasis. Time-lapse confocal microscopy revealed a SMase-induced transition from the discoid to a spherical shape, followed by PS exposure, and finally loss of cytoplasmic content. Also, SMase treatment resulted in ceramide-associated alterations in membrane–cytoskeleton interactions and membrane organization, including microdomain formation. Furthermore, we observed increases in membrane fragility, vesiculation and invagination, and large protein clusters. These changes were associated with enhanced erythrocyte retention in a spleen-mimicking model. Erythrocyte storage under blood bank conditions and during physiological aging increased the sensitivity to SMase. A low SMase activity already induced morphological and structural changes, demonstrating the potential of SMase to disturb erythrocyte homeostasis. Our analyses provide a comprehensive picture in which ceramide-induced changes in membrane microdomain organization disrupt the membrane–cytoskeleton interaction and membrane integrity, leading to vesiculation, reduced deformability, and finally loss of erythrocyte content. Understanding these processes is highly relevant for understanding anemia during chronic inflammation, especially in critically ill patients receiving blood transfusions. 相似文献
74.
P.Fernández de Palencia M.C. Martín-Hernández H.M.L.J. Joosten & C. Peláez 《Letters in applied microbiology》1997,25(3):215-219
Proteinase-deficient (Prt− ) and aminopeptidase-deficient (Amp− ) variants of Lactobacillus casei subsp. casei IFPL 731 were isolated and characterized. The Prt− mutant was isolated from strains that developed poorly on glucose milk agar. The Amp− mutant was isolated on the basis of its inability to hydrolyse L -leucine-β-naphtylamide. The Prt− variant developed poorly, while in milk the Amp− variant grew at about the same rate as the parental strain. The characterization of aminopeptidase activity in more detail showed that at least two enzymes are involved The results of the present study suggest that the proteolytic system of Lactobacillus casei is subjected to a regulatory system. 相似文献
75.
Janssen SP Gerard S Raijmakers ME Truin M Van Kleef M Joosten EA 《Neurochemistry international》2012,60(1):21-30
Elevated spinal extracellular γ-aminobutyric acid (GABA) levels have been described during spinal cord stimulation (SCS)-induced analgesia in experimental chronic peripheral neuropathy. Interestingly, these increased GABA levels strongly exceeded the time frame of SCS-induced analgesia. In line with the former, pharmacologically-enhanced extracellular GABA levels by GABAB receptor agonists in combination with SCS in non-responders to SCS solely could convert these non-responders into responders. However, similar treatment with GABAA receptor agonists and SCS is known to be less efficient. Since K+ Cl− cotransporter 2 (KCC2) functionality strongly determines proper GABAA receptor-mediated inhibition, both decreased numbers of GABAA receptors as well as reduced KCC2 protein expression might play a pivotal role in this loss of GABAA receptor-mediated inhibition in non-responders. Here, we explored the mechanisms underlying both changes in extracellular GABA levels and impaired GABAA receptor-mediated inhibition after 30 min of SCS in rats suffering from partial sciatic nerve ligation (PSNL). Immediately after cessation of SCS, a decreased spinal intracellular dorsal horn GABA-immunoreactivity was observed in responders when compared to non-responders or sham SCS rats. One hour later however, GABA-immunoreactivity was already increased to similar levels as those observed in non-responder or sham SCS rats. These changes did not coincide with alterations in the number of GABA-immunoreactive cells. C-Fos/GABA double-fluorescence clearly confirmed a SCS-induced activation of GABA-immunoreactive cells in responders immediately after SCS. Differences in spinal dorsal horn GABAA receptor-immunoreactivity and KCC2 protein levels were absent between all SCS groups. However, KCC2 protein levels were significantly decreased compared to sham PSNL animals. In conclusion, reduced intracellular GABA levels are only present during the time frame of SCS in responders and strongly point to a SCS-mediated on/off GABAergic release mechanism. Furthermore, a KCC2-dependent impaired GABAA receptor-mediated inhibition seems to be present both in responders and non-responders to SCS due to similar KCC2 and GABAA receptor levels. 相似文献
76.
Genetic diversity within and between European pig breeds using microsatellite markers 总被引:5,自引:0,他引:5
SanCristobal M Chevalet C Haley CS Joosten R Rattink AP Harlizius B Groenen MA Amigues Y Boscher MY Russell G Law A Davoli R Russo V Désautés C Alderson L Fimland E Bagga M Delgado JV Vega-Pla JL Martinez AM Ramos M Glodek P Meyer JN Gandini GC Matassino D Plastow GS Siggens KW Laval G Archibald AL Milan D Hammond K Cardellino R 《Animal genetics》2006,37(3):189-198
77.
Genetic diversity in European pigs utilizing amplified fragment length polymorphism markers 总被引:4,自引:0,他引:4
SanCristobal M Chevalet C Peleman J Heuven H Brugmans B van Schriek M Joosten R Rattink AP Harlizius B Groenen MA Amigues Y Boscher MY Russell G Law A Davoli R Russo V Dèsautés C Alderson L Fimland E Bagga M Delgado JV Vega-Pla JL Martinez AM Ramos M Glodek P Meyer JN Gandini G Matassino D Siggens K Laval G Archibald A Milan D Hammond K Cardellino R Haley C Plastow G 《Animal genetics》2006,37(3):232-238
The use of DNA markers to evaluate genetic diversity is an important component of the management of animal genetic resources. The Food and Agriculture Organisation of the United Nations (FAO) has published a list of recommended microsatellite markers for such studies; however, other markers are potential alternatives. This paper describes results obtained with a set of amplified fragment length polymorphism (AFLP) markers as part of a genetic diversity study of European pig breeds that also utilized microsatellite markers. Data from 148 AFLP markers genotyped across samples from 58 European and one Chinese breed were analysed. The results were compared with previous analyses of data from 50 microsatellite markers genotyped on the same animals. The AFLP markers had an average within-breed heterozygosity of 0.124 but there was wide variation, with individual markers being monomorphic in 3-98% of the populations. The biallelic and dominant nature of AFLP markers creates a challenge for their use in genetic diversity studies as each individual marker contains limited information and AFLPs only provide indirect estimates of the allelic frequencies that are needed to estimate genetic distances. Nonetheless, AFLP marker-based characterization of genetic distances was consistent with expectations based on breed and regional distributions and produced a similar pattern to that obtained with microsatellites. Thus, data from AFLP markers can be combined with microsatellite data for measuring genetic diversity. 相似文献
78.
79.
80.
Bart Ferwerda Matthew B. B. McCall Maaike C. de Vries Joost Hopman Boubacar Maiga Amagana Dolo Ogobara Doumbo Modibo Daou Dirk de Jong Leo A. B. Joosten Rudi A. Tissingh Frans A. G. Reubsaet Robert Sauerwein Jos W. M. van der Meer André J. A. M. van der Ven Mihai G. Netea 《PloS one》2009,4(9)