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111.
Ionov M Wróbel D Gardikis K Hatziantoniou S Demetzos C Majoral JP Klajnert B Bryszewska M 《Chemistry and physics of lipids》2012,165(4):408-413
Large unilamellar liposomes and multilamellar vesicles consisting of DMPC interacted with cationic phosphorus-containing dendrimers CPDs G3 and G4. DSC and ζ-potential measurements have shown that liposomal-dendrimeric molecular recognition probably occurs due to the interaction between the complementary surface groups. Calorimetric studies indicate that the enthalpy of the transition of the lipids that interact with CPDs is dependent on the dendrimers generation. These results can be used in order to rationally design mixed modulatory liposomal locked-in dendrimeric, drug delivery nano systems. 相似文献
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113.
Zifa E Daniil Z Skoumi E Stavrou M Papadimitriou K Terzenidou M Kostikas K Bagiatis V Gourgoulianis KI Mamuris Z 《Molecular biology reports》2012,39(4):4697-4708
A number of studies suggest that mitochondrial dysfunction plays a role in the pathogenesis of asthma. To shed light for the
first time on the role of the mitochondrial genome in the etiology of asthma we analyzed the mitochondrial tRNA genes and
part of their flanking regions in patients with asthma compared with a set of healthy controls. We found a total of 10 mutations
in 56 out of 76 asthmatic patients. Four of these mutations were not found in the control group, five were observed at a significantly
lower frequency in controls, but none of the combinations of mutations detected in asthma patients was observed in the controls.
Furthermore, we observed that 27.6% of the asthma patients (vs. 4% of the controls) belonged to the haplogroup U (Fisher test
P = 0.00) and a positive significant correlation was found between the occurrence of the haplogroup U and the severity of the
disease (Fisher test P = 0.02). Whereas further studies in larger cohorts are needed to confirm these observations we suggest that the mitochondrial
genetic background plays a key role in asthma development. 相似文献
114.
Sergentanis TN Economopoulos KP Choussein S Vlahos NF 《Molecular biology reports》2012,39(11):9921-9930
This meta-analysis aims to examine whether the genotype status of MspI, Ile462Val, and Thr461Asn polymorphisms in Cytochrome P450 1A1 (CYP1A1) is associated with ovarian cancer risk. Eligible case-control studies were identified through search in MEDLINE (end of search: October 2010). Pooled odds ratios (ORs) were appropriately derived from fixed effects or random effects models. Concerning MspI polymorphism, seven studies were eligible (1,051 cases and 1,613 controls); 11 studies were eligible (1,680 cases and 3,345 controls) for Ile462Val and three studies were eligible (349 cases and 785 controls) for Thr461Asn. Ile462Val polymorphism seemed to confer elevated ovarian cancer risk concerning homozygous carriers (pooled OR?=?2.65, 95?% CI: 1.40-5.03, p?=?0.003, fixed effects), as well as at the recessive model (pooled OR?=?2.10, 95?% CI: 1.13-3.92, p?=?0.020, fixed effects); these findings were replicated upon Caucasian subjects. MspI polymorphism was not associated with ovarian cancer risk (for heterozygous TC vs TT carriers pooled OR?=?1.10, 95?% CI: 0.91-1.34, p?=?0.329, fixed effects; for homozygous CC vs. TT carriers pooled OR?=?1.11, 95?% CI: 0.65-1.90, p?=?0.693, fixed effects). With respect to Thr461Asn polymorphism a finding of borderline statistical significance emerged, pointing to marginally elevated ovarian cancer risk in heterozygous Thr/Asn carriers (pooled OR?=?1.62, 95?% CI: 0.97-2.70, p?=?0.066, fixed effects), but not in homozygous Asn/Asn carriers (pooled OR?=?1.40, 95?% CI: 0.18-10.89, p?=?0.749, fixed effects). Ile462Val status seems to represent a meaningful risk factor for ovarian cancer in Caucasians. Additional case-control studies of high methodological quality are needed in order to further substantiate and enrich the present findings. Special attention should be paid upon the design of future studies; Asian and African populations should represent points of focus. 相似文献
115.
Apostolidou E Kambas K Chrysanthopoulou A Kourtzelis I Speletas M Ritis K Mitroulis I 《Molecular biology reports》2012,39(5):5503-5510
Familial Mediterranean fever (FMF) is an autoinflammatory disease, characterized by MEFV gene mutations and self-limited recurrent episodes of fever and localized serositis. Complement system is a key regulator
of the inflammatory process. The aim of this study was to investigate the genetic alterations and mRNA expression pattern
of C5aR and C5L2 genes in neutrophils from attack-free FMF patients. No mutations were observed in the two receptors’ genes, while the genetic
alteration observed in the C5aR1 gene was identified as N279 K polymorphic variant. Furthermore, lower mRNA expression of C5L2 gene was observed in neutrophils from FMF patients compared to control subjects. The binding capacity of rhC5a and the ability
to produce reactive oxygen species was similar in neutrophils from healthy subjects and FMF patients and independent of the
presence of N279 K polymorphism or mRNA expression of C5L2. 相似文献
116.
117.
Impact of Fungicides on the Diversity and Function of Non-target Ammonia-Oxidizing Microorganisms Residing in a Litter Soil Cover 总被引:3,自引:0,他引:3
Puglisi E Vasileiadis S Demiris K Bassi D Karpouzas DG Capri E Cocconcelli PS Trevisan M 《Microbial ecology》2012,64(3):692-701
Litter soil cover constitutes an important micro-ecosystem in sustainable viticulture having a key role in nutrient cycling and serving as a habitat of complex microbial communities. Ammonia-oxidizing bacteria (AOB) and archaea (AOA) are known to regulate nitrification in soil while little is known regarding their function and diversity in litter. We investigated the effects of two fungicides, penconazole and cyprodinil, commonly used in vineyards, on the function and diversity of total and active AOB and AOA in a microcosm study. Functional changes measured via potential nitrification and structural changes assessed via denaturating gradient gel electrophoresis (DGGE) at the DNA and RNA levels were contrasted with pesticide dissipation in the litter layer. The latter was inversely correlated with potential nitrification, which was temporarily inhibited at the initial sampling dates (0 to 21?days) when nearly 100?% of the applied pesticide amounts was still present in the litter. Fungicides induced changes in AOB and AOA communities with RNA-DGGE analysis showing a higher sensitivity. AOA were more responsive to pesticide application compared to AOB. Potential nitrification was less sensitive to the fungicides and was restored faster than structural changes, which persisted. These results support the theory of microbial redundancy for nitrification in a stressed litter environment. 相似文献
118.
119.
Haem has been previously implicated in the function of the circadian clock, but whether iron homeostasis is integrated with circadian rhythms is unknown. Here we describe an RNA interference (RNAi) screen using clock neurons of Drosophila melanogaster. RNAi is targeted to iron metabolism genes, including those involved in haem biosynthesis and degradation. The results indicate that Ferritin 2 Light Chain Homologue (Fer2LCH) is required for the circadian activity of flies kept in constant darkness. Oscillations of the core components in the molecular clock, PER and TIM, were also disrupted following Fer2LCH silencing. Other genes with a putative function in circadian biology include Transferrin-3, CG1358 (which has homology to the FLVCR haem export protein) and five genes implicated in iron-sulfur cluster biosynthesis: the Drosophila homologues of IscS (CG12264), IscU (CG9836), IscA1 (CG8198), Iba57 (CG8043) and Nubp2 (CG4858). Therefore, Drosophila genes involved in iron metabolism are required for a functional biological clock. 相似文献