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111.

Background

Primary androgen deprivation therapy (PADT) is frequently used as a sole modality of treatment in men with localized prostate cancer, despite a lack of clinical trial data supporting its use.

Objective

To measure the impact of treatment with PADT compared to observation on overall survival in men with organ-confined prostate cancer.

Design, setting, and participants

The design was for an observational cohort from Surveillance, Epidemiology, and End Results (SEER) Medicare data. The cohort consisted of 16 535 men aged 65–80 yr at diagnosis with organ-confined well-differentiated or moderately differentiated prostate cancer who survived >1 yr past diagnosis and did not undergo treatment with prostatectomy or radiation therapy within 6 mo of diagnosis. They were diagnosed between 1991 and 1999 and followed until death or until the end of the study period (December 31, 2002).

Intervention

Study subjects were selected to receive PADT alone if they received luteinizing hormone-releasing hormone agonists or bilateral orchiectomy in the first 6 mo after diagnosis, and they were selected to be observed if they did not have claims for PADT during the same interval.

Measurements

Overall survival.

Results and limitations

After adjusting for potential confounders (ie, tumor characteristics, comorbidities, and demographics), patients who received ADT had a worse overall survival rate than patients who were observed (hazard ratio: 1.20; 95% confidence interval: 1.13–1.27).In observational studies there may be unmeasured differences between the treated and untreated groups. The SEER database does not provide information on prostate-specific antigen levels.

Conclusions

This large, population-based study suggests that PADT did not improve survival in men with localized prostate cancer, but it suggests that PADT may instead result in worse outcomes compared with observation. Patients and physicians should be cognizant of the potential long-term side effects of ADT in a patient population for which expectant observation is an acceptable treatment strategy.  相似文献   
112.
113.
The authors present a case of secondary chondrosarcomatous transformation in enchondroma in toe. The authors have discussed the available literature to throw light on differentiation of benign and malignant form.  相似文献   
114.
In a previous study, we reported that intramuscular (IM) triamcinolone improves symptoms in children with difficult asthma. In 2005, we revised our difficult asthma protocol to include assessment of airway inflammation, both directly using sputum induction and indirectly by measurement of exhaled nitric oxide (eNO). In this retrospective review, we aimed to describe (i) the changes in eNO and symptoms after a single 60 mg dose of IM triamcinolone and (ii) the changes in inflammatory markers in the subgroup with non-eosinophilic asthma (i.e., an induced sputum eosinophil differential count <2.0%). Seven children received IM triamcinolone during the study period. In all children, symptom scores fell in the week following the IM injection (P < 0.01 vs. the pre-treatment week), and remained reduced for up to 6 weeks. eNO also fell within a week after IM therapy (P < 0.01), and remained reduced for up to 4 weeks. Non-eosinophilic asthma was definitively identified in three children, and in this group, eNO and symptoms fell after the IM injection. We conclude that IM triamcinolone therapy reduces both eNO and symptoms for up to 4 weeks in children with difficult asthma. Our data provide preliminary evidence that IM triamcinolone is an effective anti-inflammatory therapy in children with induced sputum non-eosinophilic asthma.  相似文献   
115.
Investigation of potential association of SNPs (G870A, rs9344; G1722C, rs678653) of cyclin D1 gene (CCND1) with susceptibility to esophageal squamous cell carcinoma (ESCC) in Kashmir valley (India). The study included 302 subjects comprising 151 ESCC cases and 151 controls. PCR‐RFLP and direct sequencing were employed for genotyping. The G870A polymorphism, the individuals carrying GA + AA genotype was having 2.80‐fold increased risk for development of ESCC (OR 2.8, 95% CI = 1.77–4.4; P = 0.0001) compared to GG genotype. Further a significantly higher risk was observed in individuals who consume >3 cups per day of salted tea (OR = 5.1; 95% CI = 1.6–16.7; P = 0.0016) and had smoking habits (OR = 6.3; 95% CI = 2.9–13.9; P = 0.0005). We also demonstrate for the first time in CCND1 1722 locus, the CC genotype was strongly associated with increased risk of developing ESCC (OR = 2.58; 95% CI = 1.61–4.15; P = 0.0001). In addition, the frequency of polymorphic C allele was also found to be higher in cases (OR = 1.92; 95% CI = 1.37–2.69; P = 0.0002). There appears to be an influence of CCND1 G870A/G1772C genotypes on genetic susceptibility to ESCC. Mol. Carcinog. ©2011 Wiley‐Liss, Inc.  相似文献   
116.
This study deals with the synthesis of novel 2-(2,3-dioxo-2,3-dihydro-1H-indol-1-yl)-N-phenylacetamide derivatives (6a–j) from isatin (3) and 5,7-dibromoisatin (4). All newly synthesized compounds were characterized using IR, 1H NMR, MS, and elemental analysis followed by evaluation of their cytotoxic activity by XTT assay on breast cancer cell line MCF-7 and non-cancer African green monkey cell line VERO. Correlation study for QSAR and in vitro assay was performed. The outcomes indicated that electron withdrawing substitutions at para position of phenyl ring and 5, 7 positions of isatin ring and increasing lipophilicity of the compound increased the cytotoxic activity. The 2-(5,7-dibromo-2,3-dioxo-2,3-dihydro-1H-indol-1-yl)-N-(4-nitrophenyl)acetamide (6b) was found to be the most active compound in the series and demonstrated higher selectivity toward MCF-7 cell line. The IC50 values were 1.96 and 1.90 μM for test compound (6b) and vinblastin (reference drug), respectively. This indicates compound (6b) may possess equipotent cytotoxic activity to vinblastine. The compound (6b) is particularly promising, since it could kill cancer cells 19–20 times more effectively than the non-cancer cells. This property of (6b) may enable us to effectively control tumors with low side effects. Hence, we propose that 2-(5,7-dibromo-2,3-dioxo-2,3-dihydro-1H- indol-1-yl)-N-(4-nitrophenyl)acetamide may be used as lead for further development.  相似文献   
117.
118.
Diffuse large B cell lymphoma (DLBCL) is clinically and biologically heterogeneous. In most cases of DLBCL, lymphoma cells co-express vascular endothelial growth factor (VEGF) and its receptors VEGFR1 and VEGFR2, suggesting autocrine in addition to angiogenic effects. We enumerated microvessel density and scored lymphoma cell expression of VEGF, VEGFR1, VEGFR2 and phosphorylated VEGFR2 in 162 de novo DLBCL patients treated with R-CHOP (rituximab, cyclophosphamide, vincristine, doxorubicin and prednisone)-like regimens. VEGFR2 expression correlated with shorter overall survival (OS) independent of International Prognostic Index (IPI) ( P  = 0·0028). Phosphorylated VEGFR2 (detected in 13% of cases) correlated with shorter progression-free survival (PFS, P  = 0·044) and trended toward shorter OS on univariate analysis. VEGFR1 was not predictive of survival on univariate analysis, but it did correlate with better OS on multivariate analysis with VEGF, VEGFR2 and IPI ( P  = 0·036); in patients with weak VEGFR2, lack of VEGFR1 coexpression was significantly correlated with poor OS independent of IPI ( P  = 0·01). These results are concordant with our prior finding of an association of VEGFR1 with longer OS in DLBCL treated with chemotherapy alone. We postulate that VEGFR1 may oppose autocrine VEGFR2 signalling in DLBCL by competing for VEGF binding. In contrast to our prior results with chemotherapy alone, microvessel density was not prognostic of PFS or OS with R-CHOP-like therapy.  相似文献   
119.
Casitas B-cell lymphoma (Cbl)-family E3 ubiquitin ligases are negative regulators of tyrosine kinase signaling. Recent work has revealed a critical role of Cbl in the maintenance of hematopoietic stem cell (HSC) homeostasis, and mutations in CBL have been identified in myeloid malignancies. Here we show that, in contrast to Cbl or Cbl-b single-deficient mice, concurrent loss of Cbl and Cbl-b in the HSC compartment leads to an early-onset lethal myeloproliferative disease in mice. Cbl, Cbl-b double-deficient bone marrow cells are hypersensitive to cytokines, and show altered biochemical response to thrombopoietin. Thus, Cbl and Cbl-b play redundant but essential roles in HSC regulation, whose breakdown leads to hematological abnormalities that phenocopy crucial aspects of mutant Cbl-driven human myeloid malignancies.  相似文献   
120.
PURPOSE: To determine the patterns and factors predictive of positive ipsilateral breast biopsy after conservation therapy for early-stage breast cancer. METHODS AND MATERIALS: We performed a retrospective review of Stage I-II breast cancer patients initially treated with lumpectomy and radiotherapy between 1977 and 1996, who later underwent post-treatment ipsilateral breast biopsies. RESULTS: A total of 223 biopsies were performed in 193 treated breasts: 171 single and 22 multiple biopsies. Of the 223 biopsies, 56% were positive and 44% were negative for recurrence. The positive biopsy rate (PBR) was 59% for the first and 32% for subsequent biopsies. The median time to the first post-treatment biopsy was 49 months. Of the patients with negative initial biopsy findings, 11% later developed local recurrence. The PBR was 40% among patients with physical examination findings only, 65% with mammographic abnormalities only, and 79% with both findings (p = 0.001). Analysis of the procedure type revealed a PBR of 86% for core and 58% for excisional biopsies compared with 28% for aspiration cytology alone (p = 0.025). The PBR varied inversely with age at the original diagnosis: 49% if >or=51 years, 57% if 36-50 years, and 83% if 180 months after completing postlumpectomy radiotherapy (p = 0.01). The PBR was not linked with recurrence location, initial pathologic T or N stage, estrogen receptor/progesterone receptor status, or final pathologic margins (all p >or= 0.15). CONCLUSION: After definitive radiotherapy for early-stage breast cancer, a greater PBR was associated with the presence of both mammographic and clinical abnormalities, excisional or core biopsies, younger age at the initial diagnosis, and longer intervals after radiotherapy completion.  相似文献   
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