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991.
992.
AIMS: Cyclo-oxygenase (Cox) catalyses the conversion of arachidonic acid into prostaglandins (PG) and other eciosanoids. The prostaglandins, especially PGE(2) are implicated in tumorigenesis via angiogenesis and suppression of immune reactivity. There are two known isoforms of the enzyme, Cox-1, which is constitutively expressed and the inducible isoform, Cox-2. Cox-2 is induced in response to inflammatory mediators, growth factors, oncogenes and mitogens. Non-selective Cox inhibitors may reduce the relative risk of colonic and breast carcinoma. METHODS: We studied the expression of Cox-2 by immunohistochemistry in 106 primary breast carcinoma specimens collected over a three-year period, using a commercially available polyclonal antibody on formalin-fixed, paraffin-embedded tissue. The slides were examined independently by two pathologists. Tumours were classified according to accepted criteria and an immunohistochemical score (IHS) was calculated for each specimen. The IHS combines the percentage of immunoreactive cells (quantity score) and an estimate of staining intensity (staining intensity score). RESULTS: All patients were female. The mean age was 53 years, range 28-86 years. Forty percent (n=42) of tumours were node negative and 60% (n=64) node positive. Forty-nine percent (n=52) of tumours were grade 3, a further 49% (n=52) grade 2 and 2% (n=2) grade 1. There was no statistically significant correlation between IHS and tumour size, grade, histology, nodal status, estrogen receptor or progesterone receptor positivity. A trend was observed showing an IHS of zero is associated with prolonged survival compared with an IHS of 9-12. CONCLUSION: Cox-2 expression in primary breast cancer does not correlate with accepted pathological or biochemical prognostic indicators.  相似文献   
993.
Treatment of pseudoaneurysms by the injection of thrombin have been reported in the literature with a success rate approaching 100%. Complications have been reported with its use. We report a case where thrombin was used to thrombose a superficial temporal artery pseudoaneurysm leading to the development of seizure and ischaemia of the scalp. We advise that thrombin should be not be used to thrombose pseudoaneurysms of arteries supplying critical areas.  相似文献   
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目的:许多体内实验表明神经干细胞具有向胶质瘤细胞迁移的特性,该特性使神经干细胞有可能成为基因治疗脑胶质瘤潜在的基因携带者。实验拟观察大鼠星形胶质瘤C6细胞诱导体外培养的大鼠神经于细胞的迁移作用,并初步分离C6细胞中诱导神经干细胞迁移的蛋白: 方法:实验于2005—01/2006—05在南通大学江苏省神经再生重点实验室完成。实验材料:C6细胞用含10%小牛血清的DMEM/F12培养基进行培养,使用时细胞处于对数生长期:清洁级的新生1周内的SD大鼠由南通大学实验动物中心提供,实验过程中对动物处置符合动物伦理学标准。实验方法:从新生5~7dSD大鼠大脑皮质分离培养、纯化神经干细胞。从SD新生红皮鼠大脑皮质分离、培养、纯化星形胶质细胞。采用“Transwell Inserts”细胞培养室培养系统共培养36h,比较C6细胞和大鼠星形胶质细胞对体外培养的大鼠神经干细胞的迁移作用;自然系统聚丙烯酰胺凝胶蛋白电泳分离C6细胞和星形胶质细胞差异蛋白,观察各蛋白凝胶条带对神经干细胞的迁移作用。 结果:体外培养C6细胞能诱导神经干细胞迁移,迁移细胞数目与星形胶质细胞相比,差异有显著意义(P〈0.001)。将C6细胞中差异蛋白条带与神经干细胞共培养,与对应的星形胶质细胞蛋白条带相比,可观察到与相对分子质量约67000蛋白胶条共培养的神经细胞球在接近蛋白胶条的一侧细胞向胶条迁移生长。 结论:C6细胞可以诱导体外培养的神经干细胞迁移,其总蛋白在自然系统聚丙烯酰胺凝胶电泳分离实验中获得的相对分子质量为67000的蛋白组分具有诱导神经干细胞迁移的活性。  相似文献   
998.

Introduction

Internal mammary lymph node (IMN) chain assessment for breast cancer is controversial; however, current oncologic data have shed new light on its importance. Metastatic involvement of the IMN chain has implications for staging, prognosis, treatment, and survival. Here, we analyzed our data gathered during sampling of the IMN and the oncologic treatment changes that resulted from our findings.

Methods

A retrospective chart review was performed on 581 patients who underwent free-flap breast reconstruction performed by the senior author. All dissected IMNs were submitted for pathological examination. Patient demographics, oncologic data, and the results of IMN sampling were reviewed.

Results

581 patients undergoing 981 free flaps were identified. A total of 400 lymph node basins were harvested from 273 patients. Of these, nine had positive IMNs. Two of these nine patients had positive IMNs of the contralateral nonaffected breast. Five patients had positive axillary lymph nodes. Four patients had multifocal tumors, one of which was bilateral. Seven patients had an increase in cancer stage as a result of having positive IMNs. Six patients had a change in treatment: two patients required additional chemotherapy, one received adjuvant radiation therapy, and three necessitated both supplemental chemotherapy and radiation.

Conclusions

Opportunistic biopsy of the IMN while dissecting the recipient vessels is simple and results in no added morbidity. We recommend that biopsy of the IMN chain be performed whenever internal mammary vessels are dissected for microsurgical anastomosis in breast cancer patients. Positive IMN involvement should encourage thorough oncological workup and treatment reevaluation.

Level of Evidence IV

Case series.
  相似文献   
999.
The electrocardiographic changes accompanying pericarditis consist of ST elevation in most of the leads of the 12-lead electrocardiogram. The source of this ST elevation is thought to be local inflammatory changes in the epicardium underlying the inflamed pericardium. The current from this area of ST elevation must return to some unaffected region of the heart and this should be associated with a region of ST depression. This current path from the external epicardial surface has been postulated to flow back into the endocardium through the great vessels and atria. To test this hypothesis, 18 patients with pericarditis were studied by body surface potential mapping and inverse epicardial potential distributions were computed. The resultant maps were compared to those of normal people and patients with acute anterior infraction. Epicardial maps from patients with pericarditis showed a region of current flow into the heart over the great vessels and atria in all 18 patients. This pattern was not seen in normal patients or infarction patients and was consistent with the mechanism resulting in ST elevation in pericarditis being one of current flowing from the epicardium out into the thorax and black into the heart through the great vessels and atria.  相似文献   
1000.
OBJECTIVE: Mannose binding lectin (MBL) and FcgammaRII (CD32) polymorphisms have both been implicated as candidate susceptibility genes in systemic lupus erythematosus (SLE). The aim of this study was to evaluate the relationship of these polymorphisms with SLE. METHODS: We studied a cohort of 125 SLE patients from Barcelona, Spain and 138 geographically matched controls. Sequence-specific primer-polymerase chain reaction (SSP-PCR) amplification was used to determine CD32 and MBL structural polymorphisms. MBL haplotypes were established using sequence-specific oligonucleotide probing techniques. RESULTS: Patients carried the MBL codon 54 mutant allele more frequently than controls [odds ratio (OR) 2.2; 95% confidence interval (CI) 1.2-4.0; P=0.007] and the haplotype HY W52 W54 W57 was found to be significantly lower in cases compared with controls (OR 0.6; 95% CI 0.4-0.9; P=0.016). CONCLUSION: The MBL gene codon 54 mutant allele appears to be a risk factor for SLE, whilst haplotypes encoding for high levels of MBL are protective against the disease. Differences between controls and patients were not significant when considering the FcgammaRIIa polymorphisms; similar results were observed for renal affectation.  相似文献   
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