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881.
Staphylococcus aureus capsular polysaccharides (CP) are important virulence factors and represent putative targets for vaccine development. Therefore, the purpose of this study was to develop a high-throughput method to identify and discriminate the clinically important S. aureus capsular serotypes 5, 8, and NT (nontypeable). A comprehensive set of clinical isolates derived from different origins and control strains, representative for each serotype, were used to establish a CP typing system based on Fourier transform infrared (FTIR) spectroscopy and chemometric techniques. By combining FTIR spectroscopy with artificial neuronal network (ANN) analysis, a system was successfully established, allowing a rapid identification and discrimination of all three serotypes. The overall accuracy of the ANN-assisted FTIR spectroscopy CP typing system was 96.7% for the internal validation and 98.2% for the external validation. One isolate in the internal validation and one isolate in the external validation failed in the classification procedure, but none of the isolates was incorrectly classified. The present study demonstrates that ANN-assisted FTIR spectroscopy allows a rapid and reliable discrimination of S. aureus capsular serotypes. It is suitable for diagnostic as well as large-scale epidemiologic surveillance of S. aureus capsule expression and provides useful information with respect to chronicity of infection.  相似文献   
882.
Hepatitis E virus (HEV) is the etiologic agent of endemically transmitted viral hepatitis. HEV is endemic in developing countries where it occurs in sporadic and endemic forms, but autochthonous sporadic cases of hepatitis E have been reported in North America and in Europe, including Italy. The aim of the present study was to assess the seroprevalence of antibodies to HEV in immigrants from developing countries to the province of Foggia. The seroprevalence of HEV was determined in a cohort of 412 immigrants (mostly from countries in sub‐Saharan Africa) who had arrived recently in Italy. Serum samples were tested for anti‐HEV by a commercial enzyme immunoassay (EIA) based on recombinant proteins; positive results were confirmed by a Western blot assay (Recomblot HEV). A total of 88 (21.3%) of the 412 serum samples examined were reactive to IgG anti‐HEV. Eighty‐one of these samples (19.7%) were confirmed by Western blot. Anti‐HEV IgM was found in 34/81 subjects (41.9%) of the anti‐HEV IgG positive serum samples. Almost all anti‐HEV positive subjects were asymptomatic clinically, but alanine aminotransferase serum values were elevated in 28/34 (82.3%) patients with IgM anti‐HEV‐positive. The results of this study indicate high circulation of HEV in the immigrant population. The high prevalence of acute hepatitis involved mainly subjects who arrived in Italy during the same period from the same countries (Eritrea, Ethiopia, and Somalia). J. Med. Virol. 85:261–265, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
883.
Primary infection with KIPyV and WUPyV polyomaviruses occurs early in childhood followed by lifelong persistence in the body. Polyomavirus reactivation can occur in the presence of impaired immunity as in hematological malignancies or during immunosuppresssion induced by medications. In this study, reactivation of KIPyV and WUPyV was monitored by conventional PCR in plasma samples of 26 stem cell transplant patients and in 26 related bone marrow donors. Plasma samples from transplant patients were collected immediately after the end of conditioning regimen and up to 270 days after transplant. All plasma samples from transplant patients were negative for KIPyV and WUPyV DNA. Instead, KIPyV DNA was detected in two bone marrow donors. There was no evidence of KIPyV transmission from the donor to the recipient. The data suggest that detection of KIPyV in plasma is sporadic and that KPIyV and WUPyV do not affect the post‐transplant clinical course. However, further studies on a larger sample size and more sensitive PCR methods are needed to confirm these observations. J. Med. Virol. 85: 1122–1124, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
884.
885.
Psychiatric Quarterly - The Coronavirus Disease 2019 (COVID-19) can affect mental health in different ways. There is little research about psychiatric complications in hospitalized patients with...  相似文献   
886.

Purpose

We have previously reported the expression of muscarinic acetylcholine receptors (mAChR) in human breast tumors. The activation of these receptors triggered tumor cell proliferation. Considering that invasion and metastasis is the major cause of death in cancer, we investigated the action of autoantibodies against mAChR derived from breast cancer patients in stage I (T1N0Mx-IgG) on MCF-7 cells migration and metalloproteinase-9 (MMP-9) activity. We also analyzed the participation of phospholipase C/nitric oxide synthase/protein kinase C pathway.

Methods

Immunoglobulin G (IgG) was purified by chromatography in protein G-agarose from blood samples of breast cancer patients obtained under informed consent. Migration was assayed by an in vitro wound assay. MMP-9 activity was quantified by zymography.

Results

T1N0Mx-IgG promoted tumor cell migration and increased MMP9 activity mimicking the action of the muscarinic agonist carbachol. This effect was reduced not only by the presence of atropine but also by 4-DAMP or tropicamide, antagonists for M3 and M4 mAChR subtypes respectively. The actions of T1N0Mx-IgG and carbachol on MCF-7 cells, involved the participation of phospholipase C/nitric oxide synthase/protein kinase C pathway.

Conclusions

IgG from breast cancer patients in stage I could be promoting tumor progression by regulating migration and MMP-9 activity in tumor cells via mAChR activation. The presence of these autoantibodies could be determining the prognosis of breast cancer in these patients.  相似文献   
887.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with increasing prevalence, and a male-to-female ratio of 4:1. Research has been suggesting that discrepancy in prevalence may be due to the fact that females camouflage their symptoms. In this study, we aimed to systematically review evidence on the camouflage effect in females with ASD. Following the PRISMA guidelines, we reviewed empirical research published from January 2009 to September 2019 on PubMed, Web of Science, PsychInfo and Scopus databases. Thirteen empirical articles were included in this review. Overall, evidence supports that camouflaging seems to be an adaptive mechanism for females with ASD, despite the negative implications of these behaviours in their daily life.

  相似文献   
888.
Journal of Autism and Developmental Disorders - The objective of our study was to evaluate the frequency of treatable inborn errors of metabolism (IEM) in a clinical sample of Mexican children and...  相似文献   
889.
The establishment of the epigenetic mark H4K20me1 (monomethylation of H4K20) by PR-Set7 during G2/M directly impacts S-phase progression and genome stability. However, the mechanisms involved in the regulation of this event are not well understood. Here we show that SirT2 regulates H4K20me1 deposition through the deacetylation of H4K16Ac (acetylation of H4K16) and determines the levels of H4K20me2/3 throughout the cell cycle. SirT2 binds and deacetylates PR-Set7 at K90, modulating its chromatin localization. Consistently, SirT2 depletion significantly reduces PR-Set7 chromatin levels, alters the size and number of PR-Set7 foci, and decreases the overall mitotic deposition of H4K20me1. Upon stress, the interaction between SirT2 and PR-Set7 increases along with the H4K20me1 levels, suggesting a novel mitotic checkpoint mechanism. SirT2 loss in mice induces significant defects associated with defective H4K20me1–3 levels. Accordingly, SirT2-deficient animals exhibit genomic instability and chromosomal aberrations and are prone to tumorigenesis. Our studies suggest that the dynamic cross-talk between the environment and the genome during mitosis determines the fate of the subsequent cell cycle.  相似文献   
890.
In this article we analyze some of the structural characteristics of the coding section and the intron of the human chemokine CXC receptor 4 (a 7-transmembrane receptor) pre-mRNA. In the coding sequence the frequencies of the individual nucleotides do not depart significantly from 0.25, while in the intron the frequencies of the As and Gs are significantly lower and higher, respectively, than expected from a random distribution. Analysis of the pattern of association of nucleotides into triplets or couples shows that some triplets or couples occur with frequencies significantly higher or lower than expected when assuming a random association of nucleotides. In particular, in the intron combinations of the same nucleotide are over-represented. 7-or-more nucleotide repeats occur in both the coding section and the intron with frequencies which exceed the confidence limits for a random distribution. For the coding sequence this is possibly explained by the alternans of relatively similar hydrophobic-coding sections and relatively similar intervening intracellular and extracellular hydrophilic-coding sections. 7-or-more nucleotide repeats in reverse order and in reverse/complemented order occur in the intron, but not in the coding section, with frequencies which significantly exceed a random distribution. The numerous intronic repeats in reverse/complemented order may be of relevance for the secondary structure of the intron and might be one important element of the integrated splicing code.  相似文献   
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