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101.
Osteoarthritis (OA) is a group of common, chronic, and painful inflammatory joint diseases. One important finding in OA patients is a remarkable decrease in the molecular weight of hyaluronic acid (HA) in the synovial fluid of affected joints. Therapeutic HA is available to patients in most parts of the world as a viscosupplementation product for the treatment of OA. Previous clinical reports show that high molecular weight HA (HMWHA) more effectively relieves pain than low molecular weight HA (LMWHA). However, the mechanism behind this finding remains unclear. In this study, we investigated whether a LMWHA (Low‐0.9 MDa) and two types of HMWHA (High‐1.9 MDa and 6 MDa) differentially affected chondroregulatory action. We tested this using ATDC5 cell, a murine chondrocytic cell line widely used in culture systems to study chondrogenic differentiation. We found that HMWHA, especially hylan G‐F 20 (High‐6 MDa), significantly induced aggrecan and proteoglycan accumulation, nodule formation, and mRNA expression of chondrogenic differentiation markers in a time‐ and dose‐dependent manner. In addition, we showed that HMWHA prevented TNF‐α induced inhibition of chondrogenic differentiation, with no effect on cell proliferation or viability. These results reveal that HMWHA significantly promotes chondrogenic differentiation of ATDC5 cells in vitro, and suggest that HMWHA plays a significant chondroregulatory role in vivo. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1619–1627, 2014.  相似文献   
102.
103.

Purpose

The relationship between the tumor size and organs of recurrence was analyzed to identify a high-risk group for the extrahepatic recurrence of hepatocellular carcinoma (HCC) after resection.

Methods

A total of 544 patients with HCC underwent primary surgical resection for HCC between 2001 and 2010. Of these, 293 patients had a solitary tumor but no macroscopic vascular invasion. The prognostic factors for the overall survival and relapse-free survival were analyzed among these 293 patients. The recurrent organs and frequency of recurrence were also examined.

Results

The analysis of the 293 patients showed that both the overall and relapse-free survival rates of the patients with a large tumor (>7 cm in diameter) were significantly worse than those of the patients with a tumor <7 cm. The incidence of lung metastasis was remarkably high in the group of patients with tumors more than 7 cm (24.0 %), in comparison to those with tumors <7 cm. A multivariate analysis revealed that the tumor size was the only independent risk factor for lung metastasis.

Conclusions

The patients with large HCC tumors more than 7 cm in diameter were at high-risk for a poor prognosis due to a high percentage of lung metastasis, even if there was no macroscopic vascular invasion.  相似文献   
104.

Purpose

This study retrospectively assessed the mutations of the epidermal growth factor receptor (EGFR) and K-ras genes and their clinical significance in patients with resected stage I adenocarcinomas.

Methods

A total of 354 patients with resected lung adenocarcinomas were included, and 256 patients with stage I disease were analyzed for the prognostic and predictive value of these mutations.

Results

Mutations of EGFR and K-ras genes were detected in 149 (41.1 %) and 23 (6.4 %) of all tumors, and in 122 (47.6 %) and 14 (5.5 %) of stage I tumors, respectively. There were no significant differences in the disease-free survival (DFS) and overall survival (OS) between the EGFR-mutant and wild-type groups. However, the DFS and OS were significantly shorter in patients with K-ras mutations than in those without (5-year DFS: 50.8 vs. 76.9 %, 5-year OS: 70.0 vs. 86.6 %, p < 0.01). A multivariate analysis showed that K-ras mutations were an independent poor prognostic factor. Twenty-four of the 41 patients with recurrent disease after surgery were treated with an EGFR–TKI. Fifteen EGFR-mutant patients treated with an EGFR–TKI had a better prognosis than did the nine EGFR-wild-type patients.

Conclusion

The presence of an EGFR gene mutation was a predictive factor for the response to EGFR–TKI treatment in patients with resected stage I adenocarcinoma, but was not a prognostic factor. The presence of a K-ras gene mutation was a poor prognostic factor.  相似文献   
105.
BACKGROUND: beta-Catenin is known as a multifunctional protein acting as a regulator of the cadherin-mediated cell-cell adhesion system and in the Wingless/Wnt signal transduction pathway. Recent studies reported mutation of the beta-catenin gene in some tissues of hepatocellular carcinoma (HCC). METHODS: 'Nodule-in-nodule' appearance is a feature of well-differentiated HCC containing a distinct nodule of less-differentiated cancer tissue inside, and it is presumed to be a morphological expression of the dedifferentiation process. The present study immunohistochemically investigated the beta-catenin expression according to the dedifferentiation process of HCC, that is, in small well-differentiated HCC with indistinct margins, HCC with a 'nodule-in-nodule' appearance, moderately differentiated HCC, which does not have a 'nodule-in-nodule' appearance, and sarcomatous HCC. RESULTS: The expression of beta-catenin was observed in approximately 70% of small well-differentiated HCC with indistinct margins. In HCC with a 'nodule-in-nodule' appearance, membranous expression of beta-catenin was higher in the well-differentiated cancer tissues than in the less-differentiated cancer tissues (P < 0.01), cytoplasmic expression was higher in the less-differentiated cancer tissues (P < 0.01), and nuclear expression was higher in the less-differentiated cancer tissues (P < 0.001). In moderately differentiated HCC, tumors with membranous expression of beta-catenin had more frequent intrahepatic metastasis than those without having the expression (P < 0.001). CONCLUSIONS: Accumulation of beta-catenin was already present in the early stage of HCC, and in less-differentiated cancer tissue the membranous expression of beta-catenin could be related to intrahepatic metastasis.  相似文献   
106.
107.
108.
We studied the clinical effect of continuous infusion over 24 hours of meropenem (MEPM) on bacterial pneumonia in the elderly (over 65). The subjects were 26 patients (community-acquired pneumonia: moderate, n = 9; severe, n= 4; hospital-acquired pneumonia: group III, n = 13) whose performance status was 3 or 4. MEPM 1.0g/day was infused continuously for 7-14 days, and its clinical efficacy, bacteriological efficacy, and side effects were examined prospectively. It was effective in 23 of the 26 patients (community-acquired pneumonia: moderate, 8/9; severe, 3/4; hospital-acquired pneumonia: group III, 12/13; efficacy rate: 88.5%). Bactericidal effects were obtained in 3 strains of Klebsiella pneumoniae, 2 strains of Streptococcus pneumoniae, 2 strains of methicillin-sensitive Staphlococcus aureus, 1 strain of Streptococcus agalactiae and 1 strain of Proteus mirabilis, but not in 2 strains of methicillin-resistant S. aureus, 1 strain of Pseudomonas aeruginosa and 1 strain of Serratia marcescens. Mild abnormal laboratory findings were observed in 2 patients: elevation of GPT, gamma-GTP, BUN and elevation of ALP. Based on the above, continuous infusion of MEPM on bacterial pneumonia in the elderly obtained excellent clinical effects. Further study is needed to compare the efficacy of continuous versus intermittent administration of MEPM.  相似文献   
109.
A 7-year-old boy with juvenile erythroleukemia is described, whose red cells demonstrated a high content of Hb F with fetal structure and yet contained carbonic anhydrase at adult red cell level. The findings seem to exemplify the occurrence of uncoordinated expression of fetal markers and consequently the incomplete reversion to fetal-type erythropoiesis in a hematologic malignancy.  相似文献   
110.
OBJECTIVE: We previously reported that 10 mg/day of simvastatin significantly reduced clinical scores of rheumatoid arthritis (RA) in patients with active RA with hypercholesterolemia. We have also reported that a certain pharmacological concentration of simvastatin, i.e., 0.05-0.1 microM, inhibits the production of interleukin 6 (IL-6) and IL-8 and the cell proliferation induced by tumor necrosis factor-alpha (TNF-alpha) in fibroblast-like synoviocytes (FLS) derived from patients with RA in vitro. We investigated other effects of simvastatin on FLS from the standpoint of cell viability and apoptosis. METHODS: RA FLS were cultured with or without 0.05-50 microM simvastatin for 48 h. Cell viability was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was measured by flow cytometric analysis using propidium iodide and annexin-V. Caspase-3 and -9 activities were analyzed by colorimetric assays. RESULTS: High concentrations of simvastatin, i.e., 1.0-50 microM, reduced cell viability and induced prominent apoptosis in FLS in a dose-dependent manner. The apoptosis induced by simvastatin was caspase-3- and caspase-9-dependent. These effects were completely reversed in the presence of mevalonic acid or geranylgeranyl-pyrophosphate, but not in the presence of farnesyl-pyrophosphate. Further, a geranylgeranyl transferase inhibitor and a RhoA kinase inhibitor mimicked the effect of simvastatin. CONCLUSION: These data, together with our previous report, suggest that low (pharmacological range) and high concentrations of simvastatin affect FLS differently: (1) at a low concentration, it inhibits IL-6 and IL-8 production and the cell proliferation of FLS induced by TNF-alpha (2) at high concentrations, it induces apoptosis in FLS. Understanding this dose-dependent biphasic effect of simvastatin may prove important for its clinical applications in the treatment of RA.  相似文献   
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