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991.
Serotonin, a known neurotransmitter, also functions as an angiokine to promote angiogenesis. The majority of serotonin in the human body is stored in platelets, and platelet aggregation leads to significant release of serotonin in thrombotic tumor environment. We have investigated serotonin signaling in human endothelial cells. Through G-protein-coupled receptors, serotonin at physiologically relevant concentrations activated Src/PI3K/AKT/mTOR/p70S6K phosphorylation signaling, and this activation was similar to that seen with VEGF. This finding provides insight into the overlapping angiogenic signaling pathways stimulated by serotonin in tumor environment, and suggests one of the mechanisms underlying resistance to current VEGF-targeting antiangiogenic therapy against cancer. 相似文献
992.
The acquired pellicle is a tenacious organic layer covering the surface of teeth, protecting the underlying dental hard tissues. Lipids account for about one quarter of the pellicle's dry weight and are assumed to be of considerable importance for their protective properties. Nevertheless, only preliminary information is available about the nature of lipids in the pellicle. Gas chromatography coupled with electron impact ionization mass spectrometry was used to establish a convenient analytical protocol in order to obtain a qualitative and quantitative characterization of a wide range of FAs (C(12)-C(22)). In situ biofilm formation was performed on bovine enamel slabs mounted on individual splints carried by 10 subjects. A modified Folch extraction procedure was adopted to extract the lipids from the detached pellicle, followed by transesterification to fatty acid methyl esters using methanol and concentrated hydrochloric acid. Tridecanoic and nonadecanoic acid were used as internal standards suitable and reliable for robust, precise and accurate measurements. The present study demonstrates, for the first time, a procedure based on a combination of innovative specimen generation and convenient sample preparation with sensitive GC-MS analysis for the determination of the fatty acid profile of the initial oral biofilm. 相似文献
993.
The study of nematode genomes over the last three decades has relied heavily on the model organism Caenorhabditis elegans, which remains the best-assembled and annotated metazoan genome. This is now changing as a rapidly expanding number of nematodes of medical and economic importance have been sequenced in recent years. The advent of sequencing technologies to achieve the equivalent of the $1000 human genome promises that every nematode genome of interest will eventually be sequenced at a reasonable cost. As the sequencing of species spanning the nematode phylum becomes a routine part of characterizing nematodes, the comparative approach and the increasing use of ecological context will help us to further understand the evolution and functional specializations of any given species by comparing its genome to that of other closely and more distantly related nematodes. We review the current state of nematode genomics and discuss some of the highlights that these genomes have revealed and the trend and benefits of ecological genomics, emphasizing the potential for new genomes and the exciting opportunities this provides for nematological studies. 相似文献
994.
Daneshmandi S Pourfathollah AA Pourpak Z Heidarnazhad H Kalvanagh PA 《Molecular biology reports》2012,39(2):1845-1853
Asthma is a multifactor inflammatory disorder, and its management requires understanding of its various pathogenesis and control
mechanisms. Cytokines and other inflammatory mediators are important factors in asthma pathophysiology. In this study, we
evaluated the role of cytokine polymorphisms in the asthma susceptibility, progress, control, and lung functions. IL-4-C590T
polymorphism by PCR-RFLP method, IFN-γ T+874A, TNF-α-A308G, IL-6 G−174C and TGF-β T+869C variants by ARMS-PCR method and IgE
serum level by ELISA technique were determined in 81 asthmatic patients and 124 normal subjects. Asthma diagnosis, treatment
and control levels were considered using standard schemes and criteria. TNF-α−308GA genotype was more frequent in asthmatics
(P = 0.025, OR 3.352), and polymorphisms between different asthma control levels (P > 0.05) were not different. IFN-γ+874AT genotype had a positive correlation with the familial history of asthma (P = 0.034, OR 2.688). IL-6−174C allele (P = 0.045), TNF-α−308GG genotype (P = 0.002) and TNF-α−308G allele (P = 0.004) showed reduced values, and TNF-α−308GA genotype (P = 0.002) increased FEF25-75 value in asthmatics. IFN-γ+874AA genotype caused a decrease in FVC factor (P = 0.045). This study showed that TNF-α−308GA is a risk factor for asthma, but cytokine gene variants do not affect asthma
control and IgE serum levels. Variants producing lower levels of IL-6, TNF-α and IFN-γ are associated with reduced pulmonary
capacities. To achieve an appropriate schema for asthma management, further studies with consideration of different aspects
in a larger group of patients would be more elucidative. 相似文献
995.
Karkucak M Yakut T Ozkocaman V Ozkalemkas F Ali R Bayram M Gorukmez O Ocakoglu G 《Molecular biology reports》2012,39(9):8663-8667
An activating mutation of Janus kinase 2 (JAK2-V617F) was previously described in chronic myeloproliferative disorders (MPD). In previously published studies, the frequency of the JAK2-V617F mutation was determined to be 80-90 % for patients with polycythemia vera (PV) and 40-70 % for essential thrombocythemia (ET). In this study, we analyzed the relationship between the JAK2-V617F mutation and clinical-hematological parameters in Turkish patients with MPD and compared these findings with published studies from other geographic regions. A total of 148 patients were studied; of which, 70 were diagnosed with PV and 78 with ET. The mutation status of JAK2 was determined using a tetra-primer polymerase chain reaction. We found that 80 % of the PV group and 42 % of the ET group were positive for the JAK2-V617F mutation. When all patients were analyzed, the levels of white blood cells, hemoglobin and splenomegaly were significantly different in patients with the JAK2-V617F mutation (p < 0.05). To our knowledge, this study is the first to evaluate the relationship between MPD and JAK2-V617F in Turkish patients. The JAK2-V617F mutation is frequently detected in the Turkish patients with MPD, and especially in patients with PV. Hence, it would be useful to include JAK2 mutation screening in the initial evaluation of patients suspected to have MPD. 相似文献
996.
997.
Mutations in EDNRB gene have been reported to cause Waardenburg-Shah syndrome (WS4) in humans. We investigated 17 patients
with WS4 for identification of mutations in EDNRB gene using PCR and direct sequencing technique. Four genomic mutations were
detected in four patients; a G to C transversion in codon 335 (S335C) in exon 5 and a transition of T to C in codon (S361L)
in exon 5, a transition of A to G in codon 277 (L277L) in exon 4, a non coding transversion of T to A at −30 nucleotide position
of exon 5. None of these mutations were found in controls. One of the patients harbored two novel mutations (S335C, S361L)
in exon 5 and one in Intronic region (−30exon5 A>G). All of the mutations were homozygous and novel except the mutation observed
in exon 4. In this study, we have identified 3 novel mutations in EDNRB gene associated with WS4 in Pakistani patients. 相似文献
998.
Hosseini Tafreshi SA Shariati M Mofid MR Khayam Nekui M Esmaeili A 《Molecular biology reports》2012,39(3):2169-2178
VIGS (virus induced gene silencing) is considered as a powerful genomics tool for characterizing the function of genes in
a few closely related plant species. The investigations have been carried out mainly in order to test if a pre-existing VIGS
vector can serve as an efficient tool for gene silencing in a diverse array of plant species. Another route of investigation
has been the constructing of new viral vectors to act in their hosts. Our approach was the creation of a heterologous system
in which silencing of endogenous genes was achieved by sequences isolated from evolutionary remote species. In this study,
we showed that a TRV-based vector cloned with sequences from a gymnosperm, Taxus baccata L. silenced the endogenous phytoene desaturase in an angiosperm, N. benthamiana. Our results showed that inserts of between 390 and 724 bp isolated from a conserved fragment of the Taxus PDS led to silencing of its homolog in tobacco. The real time analysis indicated that the expression of PDS was reduced 2.1- to 4.0-fold in pTRV-TbPDS infected plants compared with buffer treated plants. Once the best insert is identified and the conditions are optimized
for heterologous silencing by pTRV-TbPDS in tobacco, then we can test if TRV can serve as an efficient silencing vector in Taxus. This strategy could also be used to silence a diverse array of genes from a wide range of species which have no VIGS protocol.
The results also showed that plants silenced heterologously by the VIGS system a minimally affected with respect to plant
growth which may be ideal for studying the genes that their complete loss of function may lead to decrease of plant growth
or plant death. 相似文献
999.
Kojouri GA Sadeghian S Mohebbi A Mokhber Dezfouli MR 《Biological trace element research》2012,146(2):160-166
The present study was designed to compare the effects of nano-selenium and of sodium selenite on the chemotactic and respiratory
burst activities of neutrophils in sheep. Fifteen sheep were randomly divided into three groups. Groups 1 and 2 received selenium
nanoparticles (1 mg/kg) or sodium selenite (1 mg/kg) orally, respectively, for ten consecutive days, and the third group was
considered as the control. To determine the chemotactic and respiratory burst activities of the neutrophils, the leading front
assay and the NBT test were used on heparinized blood samples that were collected at different intervals (days 0, 10th, 20th,
and 30th). The results obtained showed that the chemotactic activities in groups 1 and 2 increased significantly on the 10th,
20th, and 30th day, compared to day 0, and on the 20th day in comparison with the 10th day, while in group 2, there was a
significant decrease on the 30th day compared to the 20th day. The chemotactic activities in group 1 were significantly higher
than in group 2 on the 10th day and in the control group on the 10th, 20th, and 30th day, but the chemotactic activities in
group 2 were significantly higher than those in the control group only on the 20th day. On the 30th day into the experiment,
the respiratory bursts in groups 1 and 2 were significantly stronger in comparison with those at day 0. Overall, nano-selenium
increased the chemotactic and respiratory burst activities more significantly than sodium selenite, which is suggestive of
a stronger stimulatory effect of the Se nanoparticles on intracellular activities. 相似文献
1000.
Effects of epibiotic bacteria associated with macroalgae on barnacle larval attachment were investigated. Eight bacterial isolates obtained from samples of three macroalga species were cultured as monospecies bacterial films and tested for their activity against barnacle (Amphibalanus improvisus) attachment in field experiments (Western Baltic Sea). Furthermore, natural biofilm communities associated with the surface of the local brown alga, Fucus vesiculosus, which were exposed to different temperatures (5, 15 and 20?°C), were harvested and subsequently tested. Generally, monospecies bacterial biofilms, as well as natural microbial assemblages, inhibited barnacle attachment by 20-67%. denaturing gradient gel electrophoresis fingerprints showed that temperature treatment shifted the bacterial community composition and weakened the repellent effects at 20?°C. Repellent effects were absent when settlement pressure of cyprids was high. Nonviable bacteria tended to repel cyprids when compared to the unfilmed surfaces. We conclude that biofilms can have a repellent effect benefiting the host by preventing heavy fouling on its surface. However, severe settlement pressure, as well as stressful temperature, may reduce the protective effects of the alga's biofilm. Our results add to the notion that the performance of F.?vesiculosus may be reduced by multiple stressors in the course of global warming. 相似文献