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81.
Isolated deletions of the long arm of chromosome 5, del(5q), are observed in 10% of myelodysplastic syndromes (MDS) and are associated with a more favorable prognosis, although the clinical course varies considerably. If one or more additional chromosomal aberrations are present, this correlates with a significantly shorter overall survival. To assess the frequency of hidden abnormalities in cases with an isolated cytogenetic del(5q), we have performed a genome wide high resolution 44 K 60mer oligonucleotide array comparative genomic hybridization (aCGH) study using DNA from bone marrow cells of 12 MDS and one AML patient. In one case a single additional hidden 5.6 Mb deletion of 13q14 and in another case multiple larger aberrations involving many chromosomes were found. Fluorescence in situ hybridization demonstrated that aberrations present in 35% of the bone marrow cells can be detected by aCGH. Furthermore with oligonucleotide aCGH the deletion end points in 5q were mapped precisely, revealing a cluster of proximal breakpoints in band q14.3 (n = 8) and a distal cluster between bands q33.2 and q34 (n = 11). This study shows the high resolution of oligonucleotide CGH arrays for precisely mapping genomic alterations and for refinement of deletion end points. In addition, the high sensitivity of this method enables the study of whole bone marrow cells from MDS patients, a disease with a low blast count.  相似文献   
82.
Qin Q  Loeffler IK  Li M  Tian K  Wei F 《Virus genes》2007,34(3):299-302
Canine parvovirus (CPV) was first recognized in the late 1970 s in dogs and has mutated and spread throughout the world in canid and felid species since then. In this study, a novel CPV was isolated from the endangered red panda (Ailurus fulgens) in China. Nucleotide and phylogenetic analysis of the capsid protein VP2 gene classified the red panda parvovirus (RPPV) as a CPV-2a type. Substitution of Val for Gly at the conserved 300 residue in RPPV presents an unusual variation in the CPV-2a amino acid sequence and is further evidence for the continuing evolution of the virus. The 300 residue is important in distinguishing the antigenicity and host range of CPVs. The clinical significance and population impact of RPPV infection in captive red pandas in China is unknown and is an important topic for future research.  相似文献   
83.
Arterial hypertension (AH) is the most important independent risk factor of cardiovascular diseases. The prevalence of AH is higher than it was several decades before, and in Europe it is approximately 40%. A higher prevalence of AH has been reported in Europe than in the United States and Canada. According to the results of epidemiology of arterial hypertension in Croatia study (EH-UH), the prevalence of AH in Croatia is 37.5%. Women are more aware, they were treated more often, and blood pressure control was more frequently achieved than in men. However, body mass index and socioeconomic factors have a greater influence on blood pressure values and prevalence of AH in women. A low level of health education and inappropriate treatment are the most important reasons for the poor blood pressure control observed. Measures of primary prevention should be performed continuously and adjusted to special population subgroups. As an increase of obesity and hypertension was observed in school children, these measures should start at that age.  相似文献   
84.
85.
AIM: As the distribution of fat is increasingly related to cardiovascular events, we examined whether or not abdominal-fat quantification using magnetic resonance imaging (MRI) software is reliable, and whether or not it is related to clinical markers of fat distribution as well as to metabolic and vascular status. METHODS: We recorded the anthropometric measurements of 34 obese type 2 diabetic patients with metabolic syndrome. The patients were enrolled to evaluate their abdominal (visceral and subcutaneous) adipose tissue by single-slice L3-L4 MRI. Manual and automated analyses were compared. The relationships between anthropometric measurements, biological markers and intima-media thickness of the common carotid artery were also assessed. RESULTS: We validated the automated software to quantify abdominal-fat deposition with MRI compared with manual measurements (r2=0.95). The waist-to-hip-circumference ratio (WHR) was the only clinical parameter that correlated with the proportion and quantity of visceral and subcutaneous abdominal-adipose tissue evaluated by MRI (r=0.60). In addition, fat repartition as evaluated by WHR was related to hepatic steatosis parameters (ferritin and ALAT) and to intima-media thickness, whereas simple waist circumference was not a determinant in these obese patients. We also showed that the adiponectin-to-leptin ratio was related to adipose tissue distribution. CONCLUSION: Distribution of abdominal fat, as evaluated by MRI, can be reflected by clinical determination of the WHR. Differences in regional accumulations of abdominal fat may be specifically related to variations in the risks of steatosis and vascular rigidity among obese type 2 diabetic patients.  相似文献   
86.

Aims/hypothesis

The aims of the present work were to identify plasma metabolites that predict future type 2 diabetes, to investigate the changes in identified metabolites among individuals who later did or did not develop type 2 diabetes over time, and to assess the extent to which inclusion of predictive metabolites could improve risk prediction.

Methods

We established a nested case–control study within the Swedish prospective population-based Västerbotten Intervention Programme cohort. Using untargeted liquid chromatography-MS metabolomics, we analysed plasma samples from 503 case–control pairs at baseline (a median time of 7 years prior to diagnosis) and samples from a subset of 187 case–control pairs at 10 years of follow-up. Discriminative metabolites between cases and controls at baseline were optimally selected using a multivariate data analysis pipeline adapted for large-scale metabolomics. Conditional logistic regression was used to assess associations between discriminative metabolites and future type 2 diabetes, adjusting for several known risk factors. Reproducibility of identified metabolites was estimated by intra-class correlation over the 10 year period among the subset of healthy participants; their systematic changes over time in relation to diagnosis among those who developed type 2 diabetes were investigated using mixed models. Risk prediction performance of models made from different predictors was evaluated using area under the receiver operating characteristic curve, discrimination improvement index and net reclassification index.

Results

We identified 46 predictive plasma metabolites of type 2 diabetes. Among novel findings, phosphatidylcholines (PCs) containing odd-chain fatty acids (C19:1 and C17:0) and 2-hydroxyethanesulfonate were associated with the likelihood of developing type 2 diabetes; we also confirmed previously identified predictive biomarkers. Identified metabolites strongly correlated with insulin resistance and/or beta cell dysfunction. Of 46 identified metabolites, 26 showed intermediate to high reproducibility among healthy individuals. Moreover, PCs with odd-chain fatty acids, branched-chain amino acids, 3-methyl-2-oxovaleric acid and glutamate changed over time along with disease progression among diabetes cases. Importantly, we found that a combination of five of the most robustly predictive metabolites significantly improved risk prediction if added to models with an a priori defined set of traditional risk factors, but only a marginal improvement was achieved when using models based on optimally selected traditional risk factors.

Conclusions/interpretation

Predictive metabolites may improve understanding of the pathophysiology of type 2 diabetes and reflect disease progression, but they provide limited incremental value in risk prediction beyond optimal use of traditional risk factors.
  相似文献   
87.
Hypertension is a well‐known risk factor for the development and rupture of cerebral aneurysms. The authors conducted a study to investigate the prognostic value of admission blood pressure (BP) on prognosis in patients with subarachnoid hemorrhage (SAH). Two hundred patients with SAH were divided into two groups according to Hunt Hess score (good prognosis: 1 to 3, and poor prognosis: 4 and 5) and according to death in hospital (surveyed and died). The prognostic factors of SAH and BP changes according to Hunt Hess scores in the acute stages of the event were evaluated. Admission mean arterial BP values of the patients who died in hospital were significantly lower than in the patients who were surveyed (P=.026). The admission mean arterial BP values were found to be lower in the poor prognostic patients (Hunt Hess score of 4 and 5) (P<.001). Decreased admission BP values were found to be associated with poor prognosis and mortality.  相似文献   
88.

Background

Iodine-131 (I-131) whole-body scan (WBS) plays an important role in the management of patients with differentiated thyroid carcinoma (DTC), to detect normal thyroid remnants and recurrent or metastatic disease. A focus of I-131 accumulation outside the thyroid bed and the areas of physiological uptake is strongly suggestive of a distant functioning metastasis. However, many false-positive I-131 WBS findings have been reported in the literature.

Patient findings

We describe a series of 11 personal cases of patients with DTC, collected from 1992 to 2011, in whom diagnostic or post-treatment WBS showed false-positive retention of I-131 in various locations.

Summary

False-positive accumulations of I-131 on WBS may be classified according to the underlying pathophysiological mechanisms: external and internal contaminations by body secretions, ectopic normal thyroid and gastric tissues, inflammatory and infectious diseases, benign and malignant tumors, cysts and effusions of serous cavities, thymic uptake, and other non classified causes.

Conclusions

Clinicians must be aware of possible false-positive findings to avoid misinterpretations of the I-131 WBS, which could lead to inappropriate treatments.  相似文献   
89.
The homozygous β-thalassemias are a group of genetically inherited hemoglobin (Hb) disorders characterized by dyserythropoietic anemia. According to the degree of anemia, two main forms, sharing a common basic molecular mechanism, are distinguished: thalassemia major (TM) and thalassemia intermedia (TI). The severity of the clinical phenotype differentiates the two forms. Thalassemia major usually presents as a severe anemia requiring life-long transfusion therapy for survival.

The dramatic improvement in life expectancy of β-thalassemia (thal) patients achieved during the past few decades by virtue of therapeutic advances, has motivated investigators' interest in a better understanding of the clinical consequences of this genetic defect. Heart complications still represent the leading cause of mortality from the disease. The mechanisms of cardiac injury along with its treatment and prevention have attracted the main research efforts in this field. In this review, we present existing knowledge and our personal experience of 30 years of follow-up of over 1,000 thalassemic patients, regarding the basis of the cardiac injury, the clinical findings and the global strategy of the therapeutic intervention in TM patients who develop congestive heart failure (CHF).  相似文献   
90.
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