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991.
BACKGROUND AND OBJECTIVE: Several studies of real-time endobronchial ultrasound (EBUS)-guided transbronchial needle aspiration (TBNA) have reported a sensitivity of approximately 90% in the diagnosis of mediastinal and hilar malignancies. However, few studies have addressed its role in the diagnosis of sarcoidosis. The aim of the present study was to assess the utility of EBUS-TBNA in confirming a pathological diagnosis of sarcoidosis. METHODS: Fifteen consecutive patients with suspected sarcoidosis and mediastinal and/or hilar lymphadenopathy were investigated prospectively. EBUS-TBNA with an echo-bronchoscope and a dedicated echogenic 22-gauge needle was carried out in patients under conscious sedation, followed by conventional TBNA of the same lesion using a 19-gauge needle. RESULTS: EBUS-TBNA and/or TBNA demonstrated non-caseating epithelioid cell granulomas in 14 of 15 patients (93%). All 14 patients with a pathological diagnosis of sarcoidosis were considered to have sarcoidosis based on subsequent clinical assessments. The single patient with a negative EBUS-TBNA and TBNA had a malignant melanoma diagnosed following surgical biopsy. EBUS-TBNA confirmed a diagnosis of sarcoidosis in 13 of the 14 patients (93%) by identifying non-caseating epithelioid cell granulomas in 18 of 23 lymph nodes (78%) sampled. When two needle aspirates of one or two lymph nodes were carried out, the percentage positive pathological diagnosis for sarcoidosis for (i) EBUS-TBNA; (ii) TBNA; and (iii) the combination of EBUS-TBNA and TBNA were 93% (13 of 14 patients), 93% (13 of 14 patients) and 100% (14 of 14 patients), respectively. There were no complications associated with the procedures. CONCLUSION: EBUS-TBNA is less invasive and acceptably sensitive as a method for obtaining pathological confirmation of sarcoidosis.  相似文献   
992.
993.
BACKGROUND: Our study was planned to investigate the relationship between plasma levels of serum amyloid A protein (SAA) concentrations and the subsequent left ventricular systolic function in patients with acute myocardial infarction (AMI) treated with primary coronary angioplasty. METHODS AND RESULTS: Reperfusion by primary percutaneous coronary intervention was successful in 486 consecutive AMI patients who were admitted within 12 hours of onset. Plasma SAA concentrations were evaluated 24 hours after onset. Left ventricular (LV) function was serially determined by left ventriculography performed in the acute (soon after recanalization) and chronic phases (6 months after onset). (I) There was no significant correlation between SAA concentration and acute phase left ventricular ejection fraction (LVEF) or regional wall motion (RWM). (II) The SAA concentration was significantly correlated with both highly sensitive C-reactive protein (hs-CRP) and the peak-CK value (hs-CRP: r = 0.69, P < 0.0001, peak-CK: r = 0.21, P = 0.0003). (III) SAA was significantly negatively correlated with both LVEF and RWM in the chronic phase (LVEF: r = -0.42, P = 0.001; RWM: r = -0.41, P = 0.007). (IV) The plasma level of SAA also showed a significant negative correlation with the differences in LVEF between the 2 stages (delta-LVEF) (r = -0.43, P = 0.02). CONCLUSION: In the setting of AMI, plasma SAA concentrations may be closely related to subsequent left-ventricular systolic dysfunction.  相似文献   
994.
Klotho, a regulatory factor implicated in countering the aging process, has been reported to ameliorate endothelial dysfunction in vivo. To clarify whether Klotho protein directly affects endothelial cell function, we studied the effects of membrane-form Klotho on manganese superoxide dismutase (Mn-SOD) expression and nitric oxide production in human umbilical vein endothelial cells (HUVEC). We incubated HUVEC with conditioned medium from COS-1 cells transfected with expression vector, pCAGGS-klotho (Klotho-CM) or a recombinant, purified 6His-tagged Klotho protein. Both Klotho-CM and 6His-tagged Klotho protein enhanced Mn-SOD expression by approximately two-fold, partially via activation of the cAMP signaling pathway. Furthermore, Klotho-CM increased nitric oxide production, which also contributed to the up-regulation of Mn-SOD. Using the oxidation-sensitive dye dihydroethidium, we found that Klotho inhibited angiotensin II-induced reactive oxygen species production in HUVEC. These findings provide new insights into the mechanisms of Klotho action and support the therapeutic potential of membrane-form Klotho to regulate endothelial function. Hiromi Rakugi and Naomichi Matsukawa contributed equally to this work.  相似文献   
995.
996.
Basaloid squamous cell carcinoma (BSC) of the esophagus is a rare malignant disease. We report here a patient with recurrent esophageal BSC, who was successfully treated by systemic chemotherapy containing 5-fluorouracil (5-FU) and cisplatin (CDDP). A 57-year-old woman was diagnosed as having SCluamous cell carcinoma of the esophagus upon endoscopic examination. Curative esophagectomy with lymph node dissection was performed under the thoracoscope. The pathological diagnosis of the surgical specimen was BSC. Five months after operation, the patient was diagnosed as having a recurrence of the BSC with metastases to the liver and spleen, and a right paraclavicular lymph node. She was given systemic chemotherapy consisting of continuous infusion of 800 mg/d of 5-FU and 3 h infusion of 20 mg/d of CDDP for 5 consecutive days every 4 wk. The metastatic lesions in the spleen and right paraclavicular lymph node disappeared, and the liver metastasis was apparently reduced in size after 2 courses of chemotherapy. The tumor regression was seen over 6 courses, with progression afterwards. Although subsequent treatment with CPT-11 and CDDP was not effective, docetaxel and vinorelbine temporarily controlled the tumor growth for 2 mo. 5-FU and CDDP combination may be useful for the patients with advanced BSC.  相似文献   
997.
There are several cofactors which affect body iron metabolism and accelerate iron overload. Alcohol and hepatic viral infections are the most typical examples for clarifying the role of cofactors in iron overload. In these conditions, iron is deposited in hepatocytes and Kupffer cells and reactive oxygen species (ROS) produced through Fenton reaction have key role to facilitate cellular uptake of transferrin-bound iron. Furthermore,hepcidin, antimicrobial peptide produced mainly in the liver is also responsible for intestinal iron absorption and reticuloendothelial iron release. In patients with ceruloplasmin deficiency, anemia and secondary iron overload in liver and neurodegeneration are reported.Furthermore, there is accumulating evidence that fatty acid accumulation without alcohol and obesity itself modifies iron overload states. Ineffective erythropoiesis is also an important factor to accelerate iron overload,which is associated with diseases such as thalassemia and myelodysplastic syndrome. When this condition persists, the dietary iron absorption is increased due to the increment of bone marrow erythropoiesis and tissue iron overload will thereafter occurs. In porphyria cutanea tarda, iron is secondarily accumulated in the liver.  相似文献   
998.
Introduction: The clinical phenotype is 8 to 10 times more prevalent in males than in females in patients with Brugada syndrome. Brugada syndrome has been reported to be thinner than asymptomatic normal controls. We tested the hypothesis that higher testosterone level associated with lower visceral fat may relate to Brugada phenotype and male predominance.
Methods and Results: We measured body-mass index (BMI), body fat percentage (BF%), and several hormonal levels, including testosterone, in 48 Brugada males and compared with those in 96 age-matched control males. Brugada males had significantly higher testosterone (631 ± 176 vs 537 ± 158 ng/dL; P = 0.002), serum sodium, potassium, and chloride levels than those in control males by univariate analysis, and even after adjusting for age, exercise, stress, smoking, and medication of hypertension, diabetes, and hyperlipidemia, whereas there were no significant differences in other sex and thyroid hormonal levels. Brugada males had significantly lower BMI (22.1 ± 2.9 vs 24.6 ± 2.6 kg/m2; P < 0.001) and BF% (19.6 ± 4.9 vs 23.1 ± 4.7%; P < 0.001) than control males. Testosterone level was inversely correlated with BMI and BF% in both groups, even after adjusting for the confounding variables. Conditional logistic regression models analysis showed significant positive and inverse association between Brugada syndrome and hypertestosteronemia (OR:3.11, 95%CI:1.22–7.93, P = 0.017) and BMI (OR:0.72, 95%CI:0.61–0.85, P < 0.001), respectively.
Conclusions: Higher testosterone level associated with lower visceral fat may have a significant role in the Brugada phenotype and male predominance in Brugada syndrome.  相似文献   
999.
The ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type I domain 13) activity was measured by a fluorescence resonance energy transfer (FRET) assay in the plasma of healthy volunteers and thrombotic thrombocytopenic purpura (TTP) patients to examine its usefulness in the diagnosis of TTP. The plasma levels of the ADAMTS13 activity did not show a normal distribution. Its median value was 107% (range: 55-170%) in healthy volunteers, but was significantly lower in patients with TTP (acquired or familial) and in patients with hematopoietic stem cell transplantation. However, it was not significantly lower in patients with antiphospholipid syndrome (APS). The ADAMTS13 activity by a FRET assay was closely correlated with that by the ADAMTS13 multimer method (r=0.816; p<0.001). In 18 patients with less than 10% of ADAMTS13 activity by FRET assay, less than 10% of that by multimer assay was 16, thus suggesting a good correlation for a low level of ADAMTS13. These findings suggest that the ADAMTS13 FRET assay correlates well with the ADAMTS13 multimer method and it is therefore useful for making a diagnosis of TTP.  相似文献   
1000.
INTRODUCTION: Thrombomodulin (TM) is an essential cofactor in protein C activation by thrombin. Here, we evaluated the contribution of genetic variations in the TM gene to soluble TM (sTM) level and deep vein thrombosis (DVT) in Japanese. PATIENTS AND METHODS: We sequenced the TM putative promoter, exon, and 3'-untranslated region in DVT patients (n=118). Among 17 genetic variations we identified, two missense mutations (R385K, D468Y) and three common single nucleotide polymorphisms (-202G>A, 2487A>T, 2729A>C) were genotyped in a general population of 2247 subjects (1032 men and 1215 women) whose sTM levels were measured. We then compared the frequency of these mutations in DVT patients with that in the age, body mass index-adjusted population-based controls. RESULTS: We identified one neutral mutation (H381) and three missense mutations (R385K; n=2, A455V; n=53 heterozygous, n=14 homozygous, D468Y; n=2) of TM in the DVT patients. Age-adjusted mean values of sTM were lower in C-allele carriers of 2729A>C than in noncarriers in the Japanese general population (women: 16.7+/-0.3 U/ml vs. 17.9+/-0.2 U/ml, p<0.01, men: 19.4+/-0.3 U/ml vs. 20.4+/-0.3 U/ml, p=0.03). Additionally, the CC genotype of this mutation was more common in the male DVT patients than in the male individuals of the general population (odds ratio=2.76, 95% confidence interval=1.14-6.67; p=0.02). This mutation was in linkage disequilibrium (r-square>0.9) with A455V mutation. CONCLUSIONS: TM mutations, especially those with a haplotype consisting of 2729A>C and A455V missense mutation, affect sTM levels, and may be associated with DVT in Japanese.  相似文献   
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