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A fine mapping of loss of heterozygosity (LOH) was performed in oral squamous cell carcinoma (OSCC), using 12 markers on 21q11.1 approximately q21.1. We studied 43 resected primary invasive tumors and their paired normal tissues, concurrent dysplasia or carcinoma in situ in separate areas from 8 of the specimens, and 6 local recurrent carcinomas. LOH status was compared between lesions of different phases of progression within the same patient. A high frequency of LOH was observed for D21S1410, D21S120, and D21S1433 (60% each) in the primary lesions, constituting two interstitial deleted regions encompassing eight known genes. Cases showing LOH of D21S120 were significantly associated with advanced clinical stages (III and IV; P=0.02). Consistent allelic loss was observed in 64.2% of the informative cases between the precursor lesions and their corresponding invasive tumors, and in 59.5% of those between the primary lesions and their recurrent counterparts. Fewer than half of the different lesions within a given patient showed discordant allelic loss for tested markers. Our results suggest that 21q11.1 approximately q21.1 harbors tumor suppressor genes in OSCC. Genetic divergence may develop during tumor clone evolution.  相似文献   
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The completion of the human genome project and the construction of single nucleotide polymorphism (SNP) maps have lead to significant efforts to find SNPs that can be linked to pathophysiology. In silico models of complete biochemical reaction networks relate a cell's individual reactions to the function of the entire network. Sequence variations can in turn be related to kinetic properties of individual enzymes, thus allowing an in silico model-driven assessment of the effects of defined SNPs on overall cellular functions. This process is applied to defined SNPs in two key enzymes of human red blood cell metabolism: glucose-6-phosphate dehydrogenase and pyruvate kinase. The results demonstrate the utility of in silico models in providing insight into differences between red cell function in patients with chronic and nonchronic anemia. In silico models of complex cellular processes are thus likely to aid in defining and understanding key SNPs in human pathophysiology.  相似文献   
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Prevention Science - The NAMWEZA intervention was implemented, using a ten-session group format, to build skills targeting psychosocial vulnerabilities and enhancing HIV prevention among people...  相似文献   
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OBJECTIVES: To assess the relationship, if any, between complement, fetal antigen, and shaking rigors during labor and delivery. METHODS: We recruited 13 volunteers for serial blood sampling during labor and childbirth. RESULTS: Complement levels had a small but significant drop (11-15%) immediately following childbirth but had no association with fetal antigen levels or shaking rigors. Fetal antigen levels failed to show any consistent relationship with shaking rigors or the labor and delivery process. CONCLUSION: Shaking rigors do not appear to be associated with changes in either complement or fetal antigen levels. Complement levels remain stable during labor but drop immediately following birth.  相似文献   
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Sustainable food strategies for meeting nutrient needs in developing countries are not well established. The available evidence shows that more than one-third of the world’s population is facing under-nutrition, of which the most affected individuals are children and mothers from poor countries. In most developing countries, losses resulting from malnutrition are between 3 and 16% of the gross domestic product. This burden is far larger than the donor-driven and government programmes can tackle alone. As such, an innovative approach, which is independent and not donor-based, is needed to reduce the burden of malnutrition in low-income countries. In this review, we describe a context specific food-based approach for addressing malnutrition in developing countries. The approach deploys the hybrid public–private delivery model that enables cost sharing and efficiency gains in resource-poor countries. The model influences players to consider consumers’ perspectives, which often are neglected and truly engage them as key stakeholders.  相似文献   
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An 11‐year‐old boy presented with complaints of multiple skin‐colored hard lumps on the right side of his body and progressive deformity of the right leg of 7‐years duration. His parents had also noticed multiple asymptomatic pits over his right arm, palms, and soles since childhood. Examination revealed skin‐colored nontender nodules on the right half of his body and shortening of his right leg. The multiple hyperpigmented pits over the right arm, palm, and sole raised diagnostic difficulties, but histopathologic, radiologic, and biochemical investigations confirmed the features of idiopathic calcinosis cutis and porokeratotic eccrine ostial and dermal duct nevus. Unilateral idiopathic calcinosis cutis has not been previously reported in the literature, and the association with ipsilateral porokeratotic eccrine ostial and dermal duct nevus makes this case unique. Diagnostic difficulties and limited options for treatment make this case interesting academically.  相似文献   
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Background

Cardiovascular disease is a significant cause of morbidity and mortality in patients with end-stage renal disease (ESRD) and kidney transplant (KT) patients. Compared with left ventricular (LV) ejection fraction (LVEF), LV strain has emerged as an important marker of LV function as it is less load dependent. We sought to evaluate changes in LV strain using cardiovascular magnetic resonance imaging (CMR) in ESRD patients who received KT, to determine whether KT may improve LV function.

Methods

We conducted a prospective multi-centre longitudinal study of 79 ESRD patients (40 on dialysis, 39 underwent KT). CMR was performed at baseline and at 12?months after KT.

Results

Among 79 participants (mean age 55 years; 30% women), KT patients had significant improvement in global circumferential strain (GCS) (p?=?0.007) and global radial strain (GRS) (p?=?0.003), but a decline in global longitudinal strain (GLS) over 12?months (p?=?0.026), while no significant change in any LV strain was observed in the ongoing dialysis group. For KT patients, the improvement in LV strain paralleled improvement in LVEF (57.4?±?6.4% at baseline, 60.6%?±?6.9% at 12?months; p?=?0.001). For entire cohort, over 12?months, change in LVEF was significantly correlated with change in GCS (Spearman’s r?=???0.42, p?<?0.001), GRS (Spearman’s r?=?0.64, p?<?0.001), and GLS (Spearman’s r?=???0.34, p?=?0.002). Improvements in GCS and GRS over 12?months were significantly correlated with reductions in LV end-diastolic volume index and LV end-systolic volume index (all p?<?0.05), but not with change in blood pressure (all p?>?0.10).

Conclusions

Compared with continuation of dialysis, KT was associated with significant improvements in LV strain metrics of GCS and GRS after 12?months, which did not correlate with blood pressure change. This supports the notion that KT has favorable effects on LV function beyond volume and blood pessure control. Larger studies with longer follow-up are needed to confirm these findings.
  相似文献   
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