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991.

Background

Postoperative radiotherapy (PORT) for thymic tumor is still controversial. The object of the study is to evaluate the role of PORT for stage I to III thymic tumors.

Methods

The Chinese Alliance for Research in Thymomas (ChART) was searched for patients with stage I to III thymic tumors who underwent surgical resection without neoajuvant therapy between 1994 and 2012. Univariate and multivariate survival analyses were performed. Cox proportional hazard model was used to determine the hazard ratio for death.

Result

From the ChART database, 1,546 stage I to III patients were identified. Among these patients, 649 (41.98%) received PORT. PORT was associated with gender, histological type (World Health Organization, WHO), thymectomy extent, resection status, Masaoka-Koga stage and adjuvant chemotherapy. The 5-year and 10-year overall survival (OS) rates and disease-free survival (DFS) rates for patients underwent surgery followed by PORT were 90% and 80%, 81% and 63%, comparing with 96% and 95%, 92% and 90% for patients underwent surgery alone (P=0.001, P<0.001) respectively. In univariate analysis, age, histological type (WHO), Masaoka-Koga stage, completeness of resection, and PORT were associated with OS. Multivariable analysis showed that histological type (WHO) (P=0.001), Masaoka-Koga stage (P=0.029) and completeness of resection (P=0.003) were independently prognostic factors of OS. In univariate analysis, gender, myasthenia gravis, histological subtype, Masaoka-Koga stage, surgical approach, PORT and completeness of resection were associated with DFS. Multivariate analysis showed that histological subtype (P<0.001), Masaoka-Koga stage (P=0.005) and completeness of resection (P=0.006) were independent prognostic factors for DFS. Subgroup analysis showed that patients with incomplete resection underwent PORT achieved better OS and DFS (P=0.010, 0.017, respectively). However, patients with complete resection underwent PORT had the worse OS and DFS (P<0.001, P<0.001, respectively).

Conclusions

The current retrospective study indicates that PORT after incomplete resection could improve OS and DFS for patients with stage I to III thymic tumors. However for those after complete resection, PORT does not seem to have any survival benefit on the whole.  相似文献   
992.
We aimed to assess the impact of size mismatching between grafts and recipients on outcomes of infants or small children after LDLT. Between October 2006 and December 2014, 129 LDLT recipients weighing no more than 8 kg were retrospectively analyzed. The entire cohort was categorized into three groups by GRWR: GRWR<3.0% (group A, n = 38), 3.0%≤GRWR<4.0% (group B, n = 61), and GRWR≥4.0% (group C, n = 30). Baseline characteristics were similar among groups A, B, and C. Compared with groups A and B, post‐transplant alanine aminotransferase and aspartate aminotransferase within seven days were significantly higher in group C; however, differences between total bilirubin and albumin after transplantation were not prominent. Moreover, incidences of surgical complications, perioperative deaths, infections, and acute rejections were all comparable among the three groups. Five‐yr patient survival rates for groups A, B, and C were 89.5%, 88.9%, and 81.6%, respectively (p = 0.872), and the graft survival rates were 89.5%, 86.6%, and 81.6%, respectively (p = 0.846). In conclusion, GRWR between 1.9% and 5.8% would not cause noticeable adverse events for infantile LDLT recipients ≤8 kg. However, there is still a role for considering reduction in the graft mass as an applicable strategy in selected cases.  相似文献   
993.
Summary. The effect of a low-molecular-weight heparin, faxiparin (Nadroparinŕ;), on murine megakaryocytopoiesis in vitro and in vivo was studied in comparison with unfractionated heparin. The addition of fraxiparin at 1–20 IU/ml into plasma clot cultures but not serum-free agar culture significantly enhanced MK colony growth. Furthermore, fraxiparin was found to potentiate the stimulating activity of aplastic anaemia serum (AAS) but not stem cell factor (SCF), interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF) and erythropoietin (Epo), on MK colony growth in vitro , and to neutralize the inhibitory effect of platelet factor 4 (PF4) in vitro and in vivo . Fraxiparin also acted synergistically with heparin confactor II and antithrombin III to promote megakaryocyte colony formation. Intraperitoneal administration of fraxiparin twice daily for 4d at 0.1–25IU/injection increased in mice the level of blood platelet counts and the number of single MKs and CFU-MK in bone marrow. These data demonstrate that fraxiparin is able to positively regulate megakaryocytopoiesis.  相似文献   
994.
Outcome of coal worker's pneumoconiosis with acute respiratory failure   总被引:2,自引:0,他引:2  
Shen HN  Jerng JS  Yu CJ  Yang PC 《Chest》2004,125(3):1052-1058
STUDY OBJECTIVE: To investigate the clinical features and prognosis of patients with coal worker's pneumoconiosis (CWP) requiring invasive mechanical ventilation (MV) in the ICU for their first episode of acute respiratory failure (ARF), with special attention to the prognostic implication of radiographic progressive massive fibrosis (PMF). DESIGN: Retrospective study. SETTING: A 16-bed medical ICU at a community hospital. PATIENTS AND METHODS: We reviewed 53 patients with CWP and ARF requiring invasive MV in the ICU for the first time between August 1998 and March 2002. RESULTS: Of the 53 patients with CWP, 28 patients (53%) with PMF had their first ARF at a younger age than those without PMF (69.1 +/- 7.9 years vs 74.8 +/- 7.2 years, p = 0.008 [mean +/- SD]). Pneumonia (49%) was the most common cause of ARF. The mean APACHE (acute physiology and chronic health evaluation) II score was 26.0 +/- 9.9, and the mean ICU stay was 14.7 +/- 16.1 days. Twenty-one patients (40%) were weaned successfully in the ICU, with mean ventilator time of 17.0 +/- 25.1 days. The ICU and in-hospital mortality rates were 40% and 43%, respectively. The median survivals for all patients and the ICU survivors were 2.6 months and 14.3 months, respectively. Multivariate analysis showed the following risk (or protective) factors for the ICU mortality: PaCO(2) > 45 mm Hg at the time of intubation (adjusted odds ratio [OR], 0.04; 95% confidence interval [CI], 0.003 to 0.44), PaO(2)/fraction of inspired oxygen ratio < 200 mm Hg at the time of intubation (OR, 8.78; 95% CI, 1.36 to 56.48), and APACHE II score >or= 25 (OR, 11.99; 95% CI, 1.49 to 96.78). PMF was not associated with the ICU mortality (OR, 1.18; 95% CI, 0.20 to 7.10). CONCLUSIONS: Radiographic PMF was not associated with the ICU mortality in patients with CWP and ARF receiving invasive MV in the ICU. Although a substantial proportion of them could be weaned from the ventilator and discharged from the hospital, their long-term prognosis was poor.  相似文献   
995.
996.
AIM: To study the morphological and serum hyaluronic acid (HA), laminin (LN), and type Ⅳ collagen changes in hepatic fibrosis of rats induced by dimethylnitrosamine (DMN).METHODS: The rat model of liver fibrosis was induced by DMN. Serum HA, type Ⅳ collagen, and LN were measured by ELISA. The liver/weight index and morphological changes were examined under electron microscope on d 7, 14, 21, and 28 by immunohistochemical alpha smooth muscle actin α-SMA staining as well as Sirius-red and HE staining.RESUJLTS: The levels of serum HA, type Ⅳ collagen and LN significantly increased from d 7 to d 28 (P = 0.043).The liver/weight index increased on d 7 and decreased on d 28. In the model group, the rat liver stained with HE and Sirius-red showed evident hemorrhage and necrosis in the central vein of hepatic 10 lobules on d 7. Thin fibrotic septa were formed joining central areas of the liver on d 14. The number of α-SMA positive cells was markedly increased in the model group. Transitional hepatic stellate cells were observed under electron microscope.All rats in the model group showed micronodular fibrosis in the hepatic parenchyma and a network of α-SMA positive cells. Typical myofibroblasts were embedded in the core of a fibrous septum. Compared to the control group, the area-density percentage of collagen fibrosis and pathologic grading were significantly different in the model group (P<0.05) on different d (7, 14, and 28). The area-density percentage of collagen fibrosis in hepatic tissue had a positive correlation with the levels of serum HA, LN, and type Ⅳ collagen.CONCLUSION: The morphological and serum HA, type Ⅳ collagen, and LN are changed in DMN-induced liver fibrosis in rats.  相似文献   
997.
Summary An insulin-dependent diabetes mellitus (IDDM)-susceptibility gene (IDDM13) has recently been mapped to a region of distal chromosome 2q, which is syntenic to the region of mouse chromosome 1 containing a murine susceptibility gene for IDDM, Idd5. To determine the contribution of this region to IDDM disease susceptibility further and to narrow the region for positional cloning of susceptibility genes, we have studied the association of distal chromosome 2q with IDDM in the genetically distinct Japanese population. A 137 mobility unit (mu) allele at D2S137 locus was significantly associated with IDDM (odds ratio 1.92, p = 0.0016). Other markers, D2S301 and D2S143, located in the same region were not associated with IDDM, indicating that IDDM13 is in linkage disequilibrium with D2S137, but not with D2S301 or D2S143. The association of D2S137 with IDDM was observed in patients lacking one of two high risk HLA alleles, DQB1 * 0303 and DQB1 * 0401, but not in patients with either of these alleles. The frequency of high risk HLA alleles was significantly lower in patients with the susceptible allele at D2S137, suggesting that IDDM13 contributes to IDDM susceptibility in subjects without high risk genotypes at IDDM1. Demonstration of allelic association of D2S137 with IDDM localizes IDDM13 in the close vicinity (< 2 centiMorgans) of D2S137, greatly facilitating fine structure mapping and positional cloning of IDDM13. [Diabetologia (1998) 41: 228–232] Received: 27 March 1997 and in revised form: 3 October 1997  相似文献   
998.
OBJECTIVES: Epidemiological and experimental studies indicate that non‐steroidal anti‐inflammatory drugs (NSAIDs) are chemopreventive agents of gastrointestinal cancers, but few studies on gastric cancer have been carried out. A decrease in folic acid supplement and subsequent DNA hypomethylation are related to gastrointestinal cancers, and it has been shown that high‐dose folic acid may interfere with gastric carcinogenesis in dogs. The objective of this study was to investigate the effects of rofecoxib, a selective cyclooxygenase‐2 (COX‐2) inhibitor, and folic acid on the chemoprevention of gastric cancer induced by N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG) in Wistar rats, and to evaluate the cell proliferation of gastric mucosa in different experimental groups. METHODS: Eighty male Wistar rats were randomly divided into five groups (16 rats in each group). In the control group, the rats were given pure water and basal diet. In the MNNG group, the rats received MNNG in drinking water (100 mg/L) and basal diet. In the MNNG + low‐dose rofecoxib group, the rats were given MNNG and rofecoxib 5 mg/kg per day with basal diet. In the MNNG + high‐dose rofecoxib group, the rats were given MNNG and rofecoxib 15 mg/kg per day with basal diet. In the MNNG + folic acid group, the rats were given MNNG and folic acid 5 mg/kg per day with basal diet. The experiment was terminated at 50 weeks, and all rats were killed. Blood samples of 3 mL were obtained for measurement of serum folic acid concentrations in the control group, the MNNG group and the MNNG + folic acid group by using chemiluminescent method. The stomach was removed from all rats for histopathological examination and immunohistochemical study. Proliferating cell nuclear antigen (PCNA) expression in gastric epithelial cells was also determined. RESULTS: In the MNNG group, five of 11 rats (45.5%) developed gastric cancer, while in all other four groups no gastric cancer was found (P < 0.05). The positivity rate of PCNA expression in the cancerous tissues was significantly higher than that in the non‐cancerous tissues (80.0%vs 14.1%, P < 0.05). The positivity rate of PCNA expression in the gastric mucosal cells of the MNNG group was significantly higher than that in the other four groups. The mean serum folic acid concentration of rats was significantly higher in the MNNG + folic acid group (193.70 ± 60.73 ng/mL) than those in the control group (84.21 ± 25.26 ng/mL) and the MNNG group (72.27 ± 16.70 ng/mL, P < 0.05). It was shown that both low‐ and high‐dose rofecoxib as well as folic acid interfered with the development of gastric cancer induced by MNNG in Wistar rats. CONCLUSIONS: The results indicate that rofecoxib as well as folic acid interferes with gastric carcinogenesis induced by MNNG in Wistar rats, and the suppression of gastric cell proliferation may play a crucial role in the chemoprevention of gastric cancer by rofecoxib and folic acid. The higher serum folic acid concentration of rats may play an important role in the prevention of gastric cancer.  相似文献   
999.
目的分析雷帕霉素洗脱支架(SES)对糖尿病患经皮冠状动脉介入治疗后的远期影响。方法采用回顾性研究方法,在1004.例接受冠状动脉内支架术治疗的冠心病患中,84例糖尿病和250例非糖尿病患置入SES;168例糖尿病和502例非糖尿病患置入普通支架。记录并比较一般临床资料、冠状动脉造影及冠状动脉内支架术情况、远期心脏事件发生率和1年无心脏事件生存率。结果随访期间(平均16.2个月),SES组中糖尿病亚组和非糖尿病亚组的远期心脏事件发生率为4.8%比3.6%,P=0.744;1年无心脏事件生存率为95.0%比96.7%,P=0.602,两亚组差异均无统计学意义。但BMS组中,糖尿病亚组的远期心脏事件发生率显高于非糖尿病组(31.0%比21.7%,P=0.015);两亚组的1年无心脏事件生存率分别为74.2%比86.8%(P=0.001)。结论SES能显改善糖尿病患冠状动脉支架术的远期疗效,降低靶病变再狭窄和远期心脏事件的发生率,提高1年无心脏事件生存率。  相似文献   
1000.
OBJECTIVE: To explore whether there are extrinsic factors that impair the suppressive function of CD4+,CD25+ regulatory T cells in patients with untreated active systemic lupus erythematosus (SLE). METHODS: We studied 15 patients with untreated active SLE, 10 patients with SLE in remission, and 15 healthy control subjects. Percentages of CD4+,CD25+,FoxP3+ Treg cells and levels of forkhead box P3 (FoxP3) protein were analyzed by flow cytometry. Expression of messenger RNA (mRNA) for FoxP3 in purified Treg cell populations was assessed by real-time polymerase chain reaction analysis. Experiments examining Treg cell function in SLE were designed to distinguish primary from secondary T cell dysfunction. Levels of interferon-alpha (IFNalpha) in supernatants from the function assays were determined with an IFN-stimulated response element-luciferase reporter assay. RESULTS: The percentage of CD4+,CD25+, FoxP3+ cells in peripheral blood was significantly increased in SLE patients as compared with controls (mean +/- SEM 9.11 +/- 0.73% versus 4.78 +/- 0.43%; P < 0.0001). We found no difference in FoxP3 expression at either the mRNA or protein level in any CD4+,CD25+ T cell subset from SLE patients as compared with controls. Antigen-presenting cells (APCs) from SLE patients were responsible for decreased Treg cell activity and could also render dysfunctional Treg cells from healthy control subjects. CD4+,CD25+ Treg cells from SLE patients exhibited normal suppressive activity when cultured with APCs from healthy controls. A partial Treg cell blockade effect was induced by the high levels of IFNalpha derived from SLE patient APCs. CONCLUSION: We suggest that blockade of Treg cell-mediated suppression by IFNalpha-producing APCs in SLE patients may contribute to a pathogenic loss of peripheral tolerance in this disease.  相似文献   
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