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91.
E Gionti M Sanchez A Arcella G Pontarelli S Tavassi V Gentile A Cozzolino R Porta 《Cell biology international》1999,23(1):41-49
Tissue transglutaminase (tTGase) is a GTP-binding Ca(2+)-dependent enzyme which catalyses the post-translational modification via epsilon(gamma-glutamyl)lysine bridges. The physiological role of tTGase is not fully understood. It has been shown that in cartilage the expression of tTGase correlates with terminal differentiation of chondrocytes. Recent evidence suggests that the GTP-binding activity of tTGase may play a role in the control of cell cycle progression thus explaining some of the suggested roles for the enzyme.tTGase activity is present in primary cultures of epiphyseal chondrocytes and increases transiently upon retinoic acid (RA) treatment. Increase in enzyme activity occurs upon RA addition and is accompanied by a parallel increase in protein and mRNA levels. Stimulation of tTGase expression by RA correlates with suppression of cell growth and occurs independently of cell adhesion and cell differentiation.tTGase expression is not observed in MC2, a permanent chondrocyte cell line derived from retrovirus infected chondrocytes. RA treatment fails to activate tTGase expression in MC2 cells and to completely suppress cell proliferation.Our findings lend support to the idea that tTGase might play a role in non-dividing cultured chondrocytes. 相似文献
92.
Functional characterization of the neuron‐restrictive silencer element in the human tryptophan hydroxylase 2 gene expression 下载免费PDF全文
93.
Quantifying patterns of fine root dynamics is crucial to the understanding of ecosystem structure and function, and in predicting
how ecosystems respond to disturbance. Part of this understanding involves consideration of the carbon lost through root turnover.
In the context of the rainfall pattern in the tropics, it was hypothesised that rainfall would strongly influence fine root
biomass and longevity. A field study was conducted to determine root biomass, elemental composition and the influence of rainfall
on longevity of fine roots in a tropical lowland evergreen rainforest at Danum Valley, Sabah, Malaysia. A combination of root
coring, elemental analysis and rhizotron observation methods were used. Fine (less than 2 mm diameter) root biomass was relatively
low (1700 kg ha −1) compared with previously described rainforest data. Standing root biomass was positively correlated with
preceding rainfall, and the low fine root biomass in the dry season contained higher concentrations of N and lower concentrations
of P and K than at other times. Observations on rhizotrons demonstrated that the decrease in fine root biomass in the dry
season was a product of both a decrease in fine root length appearance and an increase in fine root length disappearance.
Fitting an overall model to root survival time showed significant effects of rainfall preceding root disappearance, with the
hazard of root disappearance decreasing by 8 for each 1 mm increase in the average daily (30 day) rainfall preceding root
disappearance. While it is acknowledged that other factors have a part to play, this work demonstrates the importance of rainfall
and soil moisture in influencing root biomass and root disappearance in this tropical rainforest. 相似文献
94.
95.
Yuren Wei Dong Wang Christopher L. Gentile Michael J. Pagliassotti 《Molecular and cellular biochemistry》2009,331(1-2):31-40
Chronic exposure to elevated free fatty acids, in particular long chain saturated fatty acids, provokes endoplasmic reticulum (ER) stress and cell death in a number of cell types. The perturbations to the ER that instigate ER stress and activation of the unfolded protein in response to fatty acids in hepatocytes have not been identified. The present study employed H4IIE liver cells and primary rat hepatocytes to examine the hypothesis that saturated fatty acids induce ER stress via effects on ER luminal calcium stores. Exposure of H4IIE liver cells and primary hepatocytes to palmitate and stearate reduced thapsigargin-sensitive calcium stores and increased biochemical markers of ER stress over similar time courses (6 h). These changes preceded cell death, which was only observed at later time points (16 h). Co-incubation with oleate prevented the reduction in calcium stores, induction of ER stress markers and cell death observed in response to palmitate. Inclusion of calcium chelators, BAPTA-AM or EGTA, reduced palmitate- and stearate-mediated enrichment of cytochrome c in post-mitochondrial supernatant fractions and cell death. These data suggest that redistribution of ER luminal calcium contributes to long chain saturated fatty acid-mediated ER stress and cell death. 相似文献
96.
97.
Cord Drögemüller Marco Rossi Arcangelo Gentile Stefania Testoni Hannes Jörg Gerald Stranzinger Michaela Drögemüller Marie-Louise Glowatzki-Mullis Tosso Leeb 《Mammalian genome》2009,20(1):53-59
Arachnomelia in Brown Swiss cattle is a monogenic autosomal recessive inherited congenital disorder of the skeletal system
giving affected calves a spidery look (OMIA ID 000059). Over a period of 20 years 15 cases were sampled in the Swiss and Italian
Brown cattle population. Pedigree data revealed that all affected individuals trace back to a single acknowledged carrier
founder sire. A genome scan using 240 microsatellites spanning the 29 bovine autosomes showed homozygosity at three adjacent
microsatellite markers on bovine Chr 5 in all cases. Linkage analysis confirmed the localization of the arachnomelia mutation
in the region of the marker ETH10. Fine-mapping and haplotype analysis using a total of 34 markers in this region refined the critical region of the arachnomelia
locus to a 7.19-Mb interval on bovine Chr 5. The disease-associated IBD haplotype was shared by 36 proven carrier animals
and allows marker-assisted selection. As the corresponding human and mouse chromosome segments do not contain any clear functional
candidate genes for this disorder, the mutation causing arachnomelia in the Brown Swiss cattle might help to identify an unknown
gene in bone development.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
98.
Ian P. Holmes Fabrizio Micheli Simon Gaines Olivier Lorthioir Steve P. Watson Romano Di Fabio Gabriella Gentile Christian Heidbreder Chiara Savoia Angela Worby 《Bioorganic & medicinal chemistry letters》2009,19(16):4799-4801
The synthesis and SAR of a new series of potent and selective dopamine D3 receptor antagonists is reported. 相似文献
99.
Idriss Bennacef Cristian A. Salinas Thomas A. Bonasera Roger N. Gunn Hélène Audrain Steen Jakobsen Nabeel Nabulsi David Weinzimmer Richard E. Carson Yiyun Huang Ian Holmes Fabrizio Micheli Christian Heidbreder Gabriella Gentile Tino Rossi Marc Laruelle 《Bioorganic & medicinal chemistry letters》2009,19(17):5056-5059
Compound 1 is a potent and selective antagonist of the dopamine D3 receptor. With the aim of developing a carbon-11 labeled ligand for the dopamine D3 receptor, 1 was selected as a potential PET probe. [11C]1 was obtained by palladium catalyzed cross coupling using [11C]cyanide and 4 with a specific activity of 55.5 ± 25.9 GBq/μmol (1.5 ± 0.7 Ci/μmol). [11C]1 was tested in porcine and non-human primate models to assess its potential as a radioligand for PET imaging of the dopamine D3 receptor. We conclude that in both species and despite appropriate in vitro properties, [11C]1 does not show any specific signal for the dopamine D3 receptor. 相似文献
100.
Dubreuil D Gentile MS Visalberghi E 《Proceedings. Biological sciences / The Royal Society》2006,273(1591):1223-1228
It has been reported that capuchin monkeys reject a less preferred food (LPF) when they see a partner capuchin receive a more preferred food (PF) for performing the same task. This behaviour was taken as evidence of 'inequity aversion', but an alternative hypothesis is that capuchins reject the LPF because of the mere presence of the PF. We tested this hypothesis in a paradigm, which consisted of presenting two different foods (one PF and one LPF) on a tray and allowing the capuchin to take only the LPF. Refusals to initiate the trial and refusals to take and eat the LPF were higher when the PF was hidden (hiding condition) and when the PF was accumulated in sight but out of reach of the subject (accumulation condition) compared to when two pieces of LPF were placed on the tray (control condition). Interestingly, the subject behaved as in the control condition when its partner was given and ate the PF (partner condition). We argue that capuchins' refusals were due to the frustration of seeing and not obtaining the PF, and that seeing the partner eating increases the LPF acceptance. 相似文献