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11.
Pathophysiology of muscle tone is discussed on the basis of recent knowledge about motor system organization. Decerebrate rigidity, "pyramidal" spasticity and extrapyramidal rigidity served as models of muscle tone alterations in lateral and ventral motor system lesions.  相似文献   
12.
Nimesulide release from micronized and unmicronized drug particles was tested at pH 7.4 by measuring the transfer to dimyristoylphosphatidylcholine liposomes (multilamellar and unilamellar vesicles), chosen as a biomembrane model. The perturbing effect of increasing molar fractions of pure nimesulide on the thermotropic behaviour of dimyristoylphosphatidylcholine liposomes was investigated by differential scanning calorimetry. In order to study the drug dissolution process by its uptake into void liposomes, measurements were carried out on suspensions of blank liposomes added to weighed amounts of free powdered nimesulide (micronized and unmicronized). The amount of drug transferred was quantified by comparing the effect caused by the dissolved and released drug to that caused by the free drug that had been previously molecularly dissolved in the liposomes. The calorimetric results show that the dissolution rate depends on the nimesulide form (micronized or unmicronized), and that the transfer to the void liposomes is quicker when the drug is in a micronized form. The uptake was faster when unilamellar vesicles were used instead of multilamellar vesicles because of the greater lipid surface. The calorimetric technique could represent an alternative 'in vitro' method that can be applied to the study of the dissolution kinetics directly at the site of drug uptake, mimicking a biological system.  相似文献   
13.
BACKGROUND: Mycobacterial infections are extremely complex diseases, either due to the various clinical manifestations, or to the various involved kind of mycobacteria, or to the different sensibility to antibiotics. The authors review retrospectively their series, evaluating the management of pediatric cervical lymphadenitis due to mycobacterical etiology. METHODS: From 1975 to 1998, at the Department of Pediatric Surgery of the university of Siena, 88 children were evaluated for laterocervical lymphadenopathy. Among these, 29 children, aged from 14 months to 13 years, were diagnosed as affected with lymphoadenopathy due to mycobacteria. Therapy of choice was the association of surgery and antibiotics. This behaviour allowed us to approach both advanced lesions, in active colliquation, and progressive ones. RESULTS: Results were unquestionably positive, with a complete resolution and good esthetical results in 93.2% of cases. In 6.8% of cases there was a recurrence, which required reintervention. CONCLUSIONS: On the basis of our series, we agree with the international literature in affirming that, in cases of mycobacterial lymphadenopathy, a combined antibiotic and surgical therapy is necessary. However, controversy about such a complex and difficult pathology is opened and unsolved.  相似文献   
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Background and AimsTo determine whether and to what degree exposure to isoflavone-containing soy products affects EF. Endothelial dysfunction has been identified as an independent coronary heart disease risk factor and a strong predictor of long-term cardiovascular morbidity and mortality. Data on the effects of exposure to isoflavone-containing soy products on EF are conflicting.Methods and ResultsA comprehensive literature search was conducted using the PUBMED database (National Library of Medicine, Bethesda, MD) inclusively through August 21, 2009 on RCTs using the keywords: soy, isoflavone, phytoestrogen, EF, flow mediated vasodilation, and FMD. A Bayesian meta-analysis was conducted to provide a comprehensive account of the effect of isoflavone-containing soy products on EF, as measured by FMD. A total of 17 RCTs were selected as having sufficient data for study inclusion. The overall mean absolute change in FMD (95% Bayesian CI) for isoflavone-containing soy product interventions was 1.15% (?0.52, 2.75). When the effects of separate interventions were considered, the treatment effect for isolated isoflavones was 1.98% (0.07, 3.97) compared to 0.72% (?1.39, 2.90) for isoflavone-containing soy protein. The models were not improved when considering study-specific effects such as cuff measurement location, prescribed dietary modification, and impaired baseline FMD.ConclusionsCumulative evidence from the RCTs included in this meta-analysis indicates that exposure to soy isoflavones can modestly, but significantly, improve EF as measured by FMD. Therefore, exposure to isoflavone supplements may beneficially influence vascular health.  相似文献   
17.
Ruptured abdominal aorta aneurysm (rAAA) is the 13th leading cause of death in the United States. Despite many advances in the field of vascular surgery, the improvement in mortality rates of rAAA have been very modest. Although endovascular repair has surpassed open repair for elective AAA repair in the United States, open rAAA repair remains the most common therapy for this devastating vascular emergency. In this article, we discuss open surgical management for rAAA. We also describe a fast-track algorithm we have developed at the University of Massachusetts where open and endovascular repairs play equally important roles in management of rAAA.  相似文献   
18.
Introduction Down-regulation of apoptosis genes has been implicated in the development and progression of malignant melanoma. We used cDNA microarray to evaluate pro-apoptotic gene expression comparing normal skin to melanoma (thin and thick), nodal disease and distant metastases. Methods Twenty-eight specimens including skin (n = 1), thin melanoma (n = 6), thick melanoma (n = 7), nodal disease (n = 6), and distant metastases (n = 8), were harvested at the time of resection from 16 individuals. RNA was isolated and microarray analysis utilizing the Affymetrix GeneChip (54,000 genetic elements, U133A+B... levels) was performed. Mean level of expression was calculated for each gene within a sample group. Expression profiles were then compared between tissue groups. Student’s t-test was used to determine variance in expression between groups. Results We reviewed the expression of 54,000 genetic elements, of which 2,015 were found to have significantly altered expression. This represents 1,602 genes. Twenty-two pro-apoptotic genes were found to be down-regulated when compared to normal skin. Overall reduction was evaluated comparing normal skin to metastases with a range of 3.31–64.04-fold-decrease. When comparing the tissue types sequentially, the greatest fold-decrease in gene expression occurred when comparing skin to all melanomas (thin and thick) (p = 0.011). Subset analysis comparing normal skin to thin melanoma or thick melanoma, revealed the greatest component of overall reduction at the transition from thin to thick lesions (p = 0.003). Conclusion Sequential down-regulation of pro-apoptotic genes is associated with the progression of malignant melanoma. The greatest fold-decrease occurs in the transformation from thin to thick lesions.  相似文献   
19.
AIM: Transplant renal artery stenosis (TRAS) is the most frequent vascular complication following transplantation and is a potential curable cause of resistant hypertension, allograft dysfunction, and graft loss. Percutaneous angioplasty (PTA) is the treatment of choice, but the incidence of restenosis may be as high as 35%. Alternative treatment option combines the angioplastic procedure with the placement of a stent. The aim of this study was to evaluate retrospectively the clinical outcome of 30 patients with TRAS or post-PTA recurrent TRAS between 1991 and 2006 treated by endoluminal stenting. Primary outcomes of this study were survival rate, percentage of restenosis and lost of the graft. Secondary outcomes were: reduction of blood pressure, creatinine levels and number of antihypertensive medications. METHODS: From May 1991 to May 2006 a retrospective review of stent placement procedures for TRAS was performed. Reviewed parameters included: technical success, arterial blood pressure and number of antihypertension medications, serum creatinine level before and after intervention. Thirty-two interventions in 30 allografts were carried out. Allograft survival rate was estimated using the Kaplan-Meier METHODS: RESULTS: The technical success rate of stenting was 100% with a single major complication event (a puncture site pseudoaneurysm). Mean follow-up time was 7.1 years; of the 30 allograft that underwent stent placement, all were patent at the last follow-up, with five restenosis (15.6%) of which only one needed to be retreated endoluminally. A reduction of the mean serum creatinine levels and of the number of blood pressure medications was observed. There was no difference in the survival curve of the grafts without TRAS compared to those with stenting treated TRAS. CONCLUSION: The treatment of the TRAS with selective or primary stenting is safe with a long-term patency rate. The efficacy of the stenting in this retrospective study is suggested by a decrease in mean systolic and diastolic blood pressure, serum creatinine levels and number of blood pressure medications.  相似文献   
20.

Background

In the United States in 2012, there were 16,060 new cases of chronic lymphocytic leukemia (CLL). Often CLL is clinically occult and first detected during pathologic evaluation of the sentinel lymph node biopsy (SLNB). We reviewed our experience of patients with the coexisting diagnosis of melanoma and CLL.

Methods

An institutional review board-approved review was performed on patients with CLL and melanoma treated from 1995 to 2009 at Moffitt Cancer Center and compared with the incidence of melanoma and CLL in our tumor registry patients with breast, prostate, lung, and colon cancer.

Results

Fifty-two patients (44 males; median age, 71 years [range, 46–88]) were identified with concurrent diagnoses of melanoma and CLL. Twenty-two patients (42 %) had CLL on SLNB for their melanoma. Thirty-two patients (62 %) were diagnosed with melanoma before CLL. Concomitant or prior cancer diagnoses included nonmelanoma skin cancers (N = 29), prostate (N = 6), colorectal (N = 2), and Merkel cell carcinoma (N = 2). Five of 20 patients (25 %) had metastatic melanoma found at the time of SLNB. Patients with melanoma had a tenfold increase of CLL diagnosis compared with colorectal cancer patients, an eightfold increase compared to prostate cancer patients, and a fourfold increase compared with breast cancer patients.

Conclusions

We have confirmed an increased association of CLL and melanoma. This may be related to an underlying immunologic defect; however, there has been scant investigation into this phenomenon. Surgeons and pathologists should understand this occurrence and recognize that not all grossly enlarged or abnormal sentinel lymph nodes in melanoma patients represent melanoma.  相似文献   
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