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41.
42.
Many unbalanced large copy number variants reviewed in the paper are associated with syndromic orofacial clefts, including a 1.6 Mb deletion on chromosome 3q29. The current report presents a new family with this recurrent deletion identified via whole-exome sequencing and confirmed by array comparative genomic hybridization. The proband exhibited a more severe clinical phenotype than his affected mother, comprising right-sided cleft lip/alveolus and cleft palate, advanced dental caries, heart defect, hypospadias, psychomotor, and speech delay, and an intellectual disability. Data analysis from the 3q29 registry revealed that the 3q29 deletion increases the risk of clefting by nearly 30-fold. No additional rare and pathogenic nucleotide variants were identified that could explain the clefting phenotype and observed intrafamilial phenotypic heterogeneity. These data suggest that the 3q29 deletion may be the primary risk factor for clefting, with additional genomic variants located outside the coding sequences, methylation changes, or environmental exposure serving as modifiers of this risk. Additional studies, including whole-genome sequencing or methylation analyses, should be performed to identify genetic factors underlying the phenotypic variation associated with the recurrent 3q29 deletion.  相似文献   
43.
Information about resistant pattern of Mycobacterium tuberculosis isolates against antituberculon drugs is a very important part of tuberculosis control and indicates the directions of TB policy in each country. Poland joined WHO/IUATLD global project on drug resistance surveillance, and carried out the first prospective survey, simultaneously on primary and acquired drug resistance of tuberculosis patients according WHO/IUATLD recommendations. The programme covered the whole country, basing on cooperation between the National Reference Laboratory (NRL) with regional TB laboratories. Questionnaires and cultures were obtained from patients who excreted TB bacilli during the period from 1 November 1996 to 1 November 1997 (12 months). Drug susceptibility testing to INH, SM, EMB and RMP were performed on Lowenstein-Jensen medium according to the proportion method or/and radiometric Bactec 460 TB system. 3970 TB patients bacteriologically confirmed by culture were included in a one-year study. The male to female ratio was 2.6:1. Patients were at the age of 6 to 83 years. Majority of patients (86% males and 77% of females) was older than 35 years. Primary resistance to any drug was found in 3.6% of new cases and 2.4% of those patients who excreted monoresistant strains. No monoresistance to EMB was found. 18 patients (0.6%) were infected by MDR strains. Total resistance in new cases was for INH--2.6%, for SM--1.8%, for RMP--0.7% and for EMB--0.1%. Acquired resistance to any drug was found in 17.0% of treated. Majority of patients--7.7% excreted monoresistant strains. 7.0% were infected by MDR strains. Total resistance to INH was 14.8%, to SM--9.2%, to RMP--7.8%, and to EBM--2.5%. No correlation was found between sex and primary resistance rates. Among new cases, 3.7% of males and 3.3% of females were infected with resistant strains. However, among treated patients, males (20%) excreted resistant strains twice as much as females (9.1%). Mean age of women and men infected with primary and acquired resistant strains was similar.  相似文献   
44.
The effect of butylated hydroxyanisole (BHA) administrationon the hepatic monooxygenase system of nuclear and microsomalfraction was investigated in male mice. Addition of BHA to thediet significantly lowered the content of cytochrome P-450 inliver nuclei and increased the specific activity of NADPH-cytochromec reductase and the content of cytochrome b5 in liver microsomes.Incubation of benzo[a]pyrene (BP) with liver nuclei from BHA-fedmice resulted in inhibition of binding of BP metabolites tonuclear macromolecules by 50% compared with control. However,there was no effect of BHA on the binding of BP metabolitesto macromolecules when BP was incubated with added DNA and livermicrosomes from BHA-fed mice. It has been postulated that modificationof nuclear monooxygenases by BHA may play a role in the inhibitoryeffect of BHA on BP carcinogenesis.  相似文献   
45.
Twenty-five patients with osteolytic metastases had computed tomography (CT) scans before and 3 months after palliative radiotherapy. The median % density change following single 8 Gy, 20 Gy/5#, 30 Gy/10# were: 128 (range 98–255), 141 (79–342), and 145 (65–235), respectively. It is feasible to evaluate remineralization of osteolytic lesions with palliative radiotherapy.  相似文献   
46.
Type I insulin-like growth factor receptor function in breast cancer   总被引:6,自引:0,他引:6  
Experimental evidence suggests an important role of the type I IGF receptor (IGF-IR) in breast cancer development. Breast tumors and breast cancer cell lines express the IGF-IR. IGF-IR levels are higher in cancer cells than in normal breast tissue or in benign mammary tumors. The ligands of the IGF-IR are potent mitogens promoting monolayer and anchorage-independent growth of breast cancer cells. Interference with IGF-IR activation, expression, or signaling inhibits growth and induces apoptosis in breast cancer cells. In addition, recent studies established the involvement of the IGF-IR in the regulation of breast cancer cell motility and adhesion. We have demonstrated that in MCF-7 cells, overexpression of the IGF-IR promotes E-cadherin-dependent cell aggregation, which is associated with enhanced cell proliferation and prolonged survival in three-dimensional culture.The expression or function of the IGF-IR in breast cancer cells is modulated by different humoral factors, such as estrogen, progesterone, IGF-II, and interleukin-1. The IGF-IR and the estrogen receptor (ER) are usually co-expressed and the two signaling systems are engaged in a complex functional cross-talk controlling cell proliferation.Despite the convincing experimental evidence, the role of the IGF-IR in breast cancer etiology, especially in metastatic progression, is still not clear. The view emerging from cellular and animal studies is that abnormally high levels of IGF-IRs may contribute to the increase of tumor mass and/or aid tumor recurrence, by promoting proliferation, cell survival, and cell-cell interactions. However, in breast cancer, except for the well established correlation with ER status, the associations of the IGF-IR with other prognostic parameters are still insufficiently documented.  相似文献   
47.
48.
Angiogenesis is an important step in the development of cancer. Vascular endothelial growth factor is a major regulator of breast cancer angiogenesis, the effects of which are transmitted through the kinase domain receptor (KDR). Up-regulation of KDR by periostin (POSTN) induces angiogenesis. We screened the KDR and the POSTN genes for published single nucleotide polymorphisms (SNPs) and chose two SNPs in each gene for further analyses. We carried out a case–control study consisting of 412 familial and 912 unselected breast cancer cases together with ethnically and geographically selected controls. Genotype, haplotype and genotype combination analyses were carried out to evaluate their effect on susceptibility to and prognosis of breast cancer. A haplotype in the POSTN gene was associated with an increased risk even after correction for multiple comparisons. Nominal associations between the SNPs and prognostic indicators were also observed. Tumors of the KDR 472His allele carriers were less often progesterone receptor negative according to both genotype and haplotype analyses (OR 0.61, 95%CI 0.40–0.92 and OR 0.60, 95%CI 0.40–0.91, respectively). The POSTN -33G allele carriers had more often high grade and estrogen receptor negative tumors (OR 1.75, 95%CI 1.02–3.01 and OR 1.70, 95%CI 1.04–2.78, respectively). The overall and cancer specific survival after 15 years of follow-up was more than 75%, and it did not depend on the genotype. Although a major effect of the SNPs in the KDR and the POSTN genes on breast cancer susceptibility and prognosis was excluded, the effect of the POSTN C-33G SNP on prognosis needs further characterization.  相似文献   
49.
In this study, the influence of carbonate lake sediments (Polylactide/Carbonate Lake Sediments–PLA/CLS) on the mechanical and structural properties of polylactide matrix composites was investigated. Two fractions of sediments originating from 3–8 and 8–12 m were analysed for differences in particle size by distribution (Dynamic Light Scattering–DLS), phase composition (X-ray Diffraction–XRD), the presence of surface functional groups (Fourier Transform-Infrared–FT-IR), and thermal stability (Thermogravimetric Analysis–TGA). Microscopic observations of the composite fractures were also performed. The effect of the precipitate fraction on the mechanical properties of the composites before and after conditioning in the weathering chamber was verified through peel strength, flexural strength, and impact strength tests. A melt flow rate study was performed to evaluate the effect of sediment on the processing properties of the PLA/CLS composite. Hydrophobic-hydrophilic properties were also investigated, and fracture analysis was performed by optical and electron microscopy. The addition of carbon lake sediments to PLA allows for the obtention of composites resistant to environmental factors such as elevated temperature or humidity. Moreover, PLA/CLS composites show a higher flow rate and higher surface hydrophobicity in comparison with unmodified PLA.  相似文献   
50.
The microbiological purity of textiles plays a pivotal role in the use of textiles, especially in hospitals and other medical facilities. Microbiological purity of cotton fabric was achieved by a new disinfection method using tetrabutyloammonium OXONE (TBA-OXONE) before washing. As a result of the disinfection, the cotton fabric became microbiologically pure, despite the markedly decreased washing time with respect to the widely used standard procedure. Shortening of the washing time allowed for significant energy savings. In addition, the effect of the number of disinfection and washing cycles on the tensile properties and tearing force of the fabric was examined. After 120 disinfection and washing cycles the mechanical properties of cotton fabric were only slightly worsened.  相似文献   
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