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121.

Background  

Iron supplementation could improve the hematopoietic response of erythropoiesis-stimulating agents (ESAs) used for chemotherapy-induced anemia.  相似文献   
122.
123.

Background

Moderate normobaric hyperoxia causes alveolar and vascular lung derangement in the newborn rat. Endogenous nitric oxide (NO), which promotes lung growth, is produced from the metabolism of l-arginine to l-citrulline in endothelial cells. We investigated whether administering l-citrulline by raising the serum levels of l-arginine and enhancing NO endogenous synthesis attenuates moderate hyperoxia-induced lung injury.

Methods

Newborn rats were exposed to FiO2?=?0.6 or room air for 14?days to induce lung derangement and then were administered l-citrulline or a vehicle (sham). Lung histopathology was studied with morphometric features. Lung tissues and bronchoalveolar lavage fluid (BALF) were collected for analysis. Lung vascular endothelial growth factor (VEGF), nitric oxide synthase (eNOS), and matrix metalloproteinase 2 (MMP2) gene and protein expressions were assessed.

Results

Serum l-arginine rose in the L-citr?+?hyperoxia group (p?=?0.05), as well as the Von Willebrand factor stained vessels count (p?=?0.0008). Lung VEGF immune staining, localized on endothelial cells, was weaker in the sections under hyperoxia than the l-citr?+?hyperoxia and room air groups. This pattern was comparable with the VEGF gene and protein expression profiles. Mean alveolar size increased in the untreated hyperoxia and sham-treated groups compared with the groups reared in room air or treated with l-citrulline under exposure to hyperoxia (p?=?0.0001). Lung VEGF and eNOS increased in the l-citrulline-treated rats, though this treatment did not change MMP2 gene expression but regulated the MMP2 active protein, which rose in BALF (p?=?0.003).

Conclusions

We conclude that administering l-citrulline proved effective in improving alveolar and vascular growth in a model of oxygen-induced pulmonary damage, suggesting better lung growth and matrix regulation than in untreated groups.  相似文献   
124.

Objective

Gene variants within the serotonin pathway have been associated with major depressive disorder (MDD) treatment outcomes, however a possible different modulation on pharmacological or psychological treatments has never been investigated.

Methods

One hundred sixty MDD patients were partially randomized to either inter-personal counseling (IPC) or antidepressants. The primary outcome was remission at week 8. Five serotonergic polymorphisms were investigated (COMT rs4680, HTR1A rs6295, HTR2A rs2224721, HTR2A rs7997012 and SLC6A4 rs421417).

Results

IPC (n=43) and antidepressant (n=117) treated patients did not show any difference in remission rates at week 8 (corrected for baseline severity, age and center). None of the studied gene variants impacted on response and remission rates at week 8 neither in the IPC nor in the antidepressant group. An analysis of the whole sample showed a trend of association between rs7997012 AA genotype and a better treatment outcome.

Conclusion

Our study confirms that IPC is an effective psychological intervention comparable to antidepressants in mild-moderate MDD. Polymorphisms related to the serotonin system did not exert a major effect on clinical outcomes in none of the treatment groups.  相似文献   
125.
IntroductionInsulin and the insulin-like growth factor (IGF) family play a key role in breast cancer (BC).ObjectiveIn this study, we evaluated on a genomic scale the potential prognostic value of insulin signaling in early BC.MethodsCandidate genes were selected from the published literature and gene expression profiling experiments. Three publicly available BC datasets, containing gene expression data on 502 cases, were used to test the prognostic ability of the score. The gene signature was developed on GSE1456, containing microarray data from 159 patients, split into a training set (102 breast tumors) and a validation set (n = 57). GSE3494 and GSE2990 (350 patients) were used for external validation. Univariate Mann-Whitney test was used to identify genes differentially expressed between relapsed and nonrelapsed patients. Expression of genes significantly correlated with relapse was combined in a linear score. Patients were classified as low or high risk with respect to the median value.ResultsOn the training set, 15 genes turned out to be differentially expressed: 8-year disease-free survival (DFS) was 51 and 91% in the high- and low-risk group (p < 0.001), respectively. In the validation set, DFS was 97 and 54% (p = 0.009), respectively. External validation: 8-year DFS was 72 and 61%, respectively, in GSE3494 (p = 0.03) and 74 and 55% in GSE2990 (p = 0.03). By multivariate analyses, the insulin signature was significantly associated with DFS, independently of age, hormone receptor status, nodal status, and grade.ConclusionsOur findings indicate that the insulin pathway is involved in BC prognosis at a genomic level and provide a window of selectivity for preventive and treatment strategies targeting the insulin/IGF pathway in BC patients.  相似文献   
126.
Objective:To study the shear bond strength (SBS), sites of failure, and micromorphology of bonded molar tubes used on teeth affected by dental fluorosis.Materials and Methods:This in vitro study included 140 first molars classified according to Dean''s index for dental fluorosis. Samples were divided into seven groups: (1) healthy teeth etched for 15 seconds, (2) teeth with moderate fluorosis (MOF) etched for 15 seconds, (3) teeth with MOF etched for 150 seconds, (4) teeth with MOF microabrasion etched for 15 seconds, (5) teeth with severe fluorosis (SEF) etched for 15 seconds, (6) teeth with SEF etched for 150 seconds, and (7) teeth with SEF microabrasion etched for 15 seconds. All samples were incubated and were then submitted to the SBS test and evaluated with the modified adhesive remnant index (ARI) and analyzed by using a scanning electronic microscope.Results:The SBS mean value for healthy enamel was 20 ± 10.2 MPa. For the group with MOF, the etched 150-second mean value was the highest (19 ± 7.6 MPa); for the group with SEF treated with microabrasion and etched for 15 seconds, the mean value was (13 ± 4.1 MPa). Significant differences (P ≤ .05) were found in the ARI between healthy and fluorosed groups.Conclusions:Fluorotic enamel affects the adhesion of bonded molar tubes. The use of overetching in cases of MOF and the combination of microabrasion and etching in SEF provides a suitable adhesion for fixed appliance therapy.  相似文献   
127.
128.
Cystic fibrosis (CF) lung disease severity is largely independent on the CF transmembrane conductance regulator (CFTR) genotype, indicating the contribution of genetic modifiers. The chemokine receptors CXCR1 and CXCR2 have been found to play essential roles in the pathogenesis of CF lung disease. Here, we determine whether genetic variation of CXCR1 and CXCR2 influences CF lung disease severity. Genomic DNA of CF patients in Germany (n = 442) was analysed for common variations in CXCR1 and CXCR2 using a single-nucleotide polymorphism (SNP) tagging approach. Associations of CXCR1 and CXCR2 SNPs and haplotypes with CF lung disease severity, CXCR1 and CXCR2 expression, and neutrophil effector functions were assessed. Four SNPs in CXCR1 and three in CXCR2 strongly correlated with age-adjusted lung function in CF patients. SNPs comprising haplotypes CXCR1_Ha and CXCR2_Ha were in high linkage disequilibrium and patients heterozygous for the CXCR1-2 haplotype cluster (CXCR1-2_Ha) had lower lung function compared with patients with homozygous wild-type alleles (forced expiratory volume in 1 s ≤ 70% predicted, OR 7.24; p = 2.30 × 10(-5)). CF patients carrying CXCR1-2_Ha showed decreased CXCR1 combined with increased CXCR2 mRNA and protein expression, and displayed disturbed antibacterial effector functions. CXCR1 and CXCR2 genotypes modulate lung function and antibacterial host defence in CF lung disease.  相似文献   
129.
AIM:To assess B1a cell expression in the rectal mucosa of ulcerative colitis (UC) patients in comparison with healthy controls.METHODS:Rectal mucosa biopsies were collected from 15 UC patients and 17 healthy controls.CD5 + B cells were analysed by three colour flow cytometry from rectal mucosal samples after mechanical disaggregation by Medimachine.Immunohistochemical analysis of B and T lymphocytes was also performed.Correlations between,on the one hand,rectal B1a cell concentrations and,on the other,erythrocyte sedimentation rate and C-reactive protein levels and clinical,endoscopic and histological disease activity indices were evaluated.RESULTS:Rectal B-lymphocyte (CD19 + /CD45 +) rate and concentration were higher in UC patients compared with those in healthy controls (47.85% ± 3.12% vs 26.10% ± 3.40%,P=0.001 and 501 ± 91 cells/mm 2 vs 117 ± 18 cells/mm 2,P 0.001);Rectal B1a cell density (CD5 + CD19 +) was higher in UC patients than in healthy controls (85 ± 15 cells/mm 2 vs 31 ± 6.7 cells/mm 2,P=0.009).Rectal B1a cell (CD5/CD19 +) rate correlated inversely with endoscopic classification (Rs=-0.637,P 0.05).CONCLUSION:B1a lymphocytes seem to be involved in the pathogenesis of UC,however,the role they play in its early phases and in disease activity,have yet to be defined.  相似文献   
130.
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