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531.
This study aimed to investigate the validity of self-reported hypertension and related factors in the Dehgolan Prospective Cohort Study (DehPCS). Data were obtained from 3996 participants aged 35–70 years in the enrolment phase of DehPCS. Self-reported hypertension and sociodemographic factors were collected by well-trained interviewers before hypertension diagnosis based on the reference criteria. The history of anti-hypertensive medication use and/or systolic blood pressure ≥140 (mmHg), or diastolic blood pressure ≥90 (mmHg) were considered as hypertension. Disagreement between self-reported and reference measures was assessed using sensitivity, specificity, positive, and negative predictive values (PPV and NPV), and kappa values. Binary and multinomial logistic regressions were used to investigate the correlates of validity of self-reported hypertension. The hypertension prevalence based on self-reports and the reference criteria was 19.49% and 21.60%, respectively. An acceptable percentage of kappa agreement value of 68.7% and relatively good overall agreement of 89.8% were found. Self-reported hypertension was guaranteed moderate sensitivity of 72.0% and high specificity of 94.5%, as well as the NPV and PPV of 92/7% and 77/9%, respectively. The chances of false-positive and false-negative reporting increased with older age, higher BMI, and a family history of hypertension. Being female, older age, higher BMI, concurrent diabetes, and stronger family ties to hypertension patients significantly increased the chance of reporting true positives relative to true negatives. Although, self-reported hypertension has an acceptable validity and can be used as a valid tool for screening epidemiological studies, it needs to be investigated because its validity is affected by age, gender, family history of hypertension, and other socio-demographic characteristics.  相似文献   
532.

Aims

Type 2 diabetes is a chronic metabolic disorder and one of the most common non-contagious diseases which is on the rise all over the world. The present study aims to assess the trend of change in fasting blood sugar (FBS) and factors associated with the progression and regression of type 2 diabetes. Moreover, this study estimates transition intensities and transition probabilities among various states using the multi-state Markov model.

Methods

In this study Multi-Ethnic Study of Atherosclerosis (MESA) dataset, from a longitudinal study, was used. The study, at the beginning, included 6814 individuals who were followed during the five phases of the study. FBS, serving as the criterion to assess the progression of diabetes, was classified into four states including (a) normal (FBS < 100 mg/dl), (b) impaired fasting glucose I (IFG I) (100 mg/dl < FBS < 110 mg/dl), (c) impaired fasting glucose II (IFG II) (110 mg/dl < FBS < 126 mg/dl), and (d) diabetes status (FBS > 126 mg/dl). A continuous-time Markov process was used to describe the evaluation of disease changes over the four states. The model estimated the mean sojourn time for each state.

Results

Based on the results obtained from fitting the Markov model, the transition probability for a normal individual to remain in the same status over a 10-year period was 0.63, while the probability for a person in the diabetes state was 0.40. The mean sojourn time for the normal and diabetic individuals aged 45–84 years was 6.26 and 5.20 respectively. The covariates of age, race, body mass index (BMI), physical activity, waist-to-hip ratio (WHR) and blood pressure, significantly affected the progression and regression of diabetes.

Conclusion

An increase in physical activity could be the most important factor in the regression of diabetes, while an increase in WHR and BMI could be the most significant factors in progression of the disease.  相似文献   
533.
OBJECTIVE: To investigate the possible implications of polymorphism in the CRH promoter in rheumatoid arthritis (RA) susceptibility, we examined a series of patients with RA from a defined area of Northwest Spain. METHODS: A total of 177 patients with RA and 147 ethnically matched controls from the Lugo region of Northwest Spain were studied. Patients and controls were genotyped for CRH polymorphisms in the 5' regulatory region of the gene at position 1273 (alleles A1 and A2) and at position 225 (alleles B1 and B2) by PCR-restriction fragment length polymorphism. Patients were stratified for age at onset of disease and rheumatoid factor status. RESULTS: When the whole group of patients was examined, no significant differences in CRH allele or genotype frequency were found compared with controls. However, the CRH allele A2 was significantly increased in patients with late onset seronegative RA compared with the seronegative group with younger age of disease onset (p = 0.03). In addition, 4 (36.4%) of the 11 patients with late onset seronegative RA carried the CRH-A2 allele versus only 2 (6.6%) of 31 patients with seronegative RA beginning before age 61 (OR 8.3, 95% CI 1.4-47.0; p = 0.015). CONCLUSION: In Northwest Spain, polymorphism in the CRH gene regulatory region may play a role as a disease susceptibility marker for late onset seronegative RA.  相似文献   
534.
OBJECTIVE: To assess the influence of interleukin 1 receptor antagonist gene polymorphism (IL1RN) in the incidence of Henoch-Sch?nlein purpura (HSP) and cutaneous leukocytoclastic angiitis (CLA) and to determine if implications exist with severe systemic complications of HSP, in particular with severe renal involvement and permanent renal dysfunction (renal sequelae). METHODS: Patients from Northwest Spain with primary cutaneous vasculitis classified as HSP or hypersensitivity vasculitis (HV) according to proposed criteria were studied. Patients with HV were included if they had a biopsy proven small size blood vessel leukocytoclastic vasculitis limited to skin and also fulfilled the Chapel Hill Consensus Conference on the Nomenclature of Systemic Vasculitis definitions for CLA. All patients were required to have had at least 2 years' followup. Patients and ethnically matched controls were genotyped for IL-1 receptor antagonist intron 2 VNTR polymorphism. RESULTS: We examined 96 Caucasian patients (58 HSP and 38 CLA) and 109 controls. No allele or genotype differences between the whole group of HSP or CLA patients and controls were observed. We found a significant association between carriage of IL-1 receptor antagonist allele 2 (ILRN*2) and severe renal involvement, manifested as nephrotic syndrome and/or renal insufficiency (p = 0.016), and permanent renal involvement (renal sequelae) (p = 0.012). CONCLUSION: In unselected patients with cutaneous vasculitis, carriage of ILRN*2 alleles influences disease severity rather than susceptibility.  相似文献   
535.
Chronic hypercoagulable state expressed clinically by thromboembolic events has been described in thalassemia. One of the affected organs is the brain where symptomatic and asymptomatic damage has been reported. The present report describes seven cases who presented with the signs of cerebrovascular accident (CVA), five ischemic and two with hemorrhage. Two of them died. All patients were splenectomized, five received regular blood transfusions, and their ferritin levels were between 1,200 and 3,000 mg %. In addition, four patients had congestive heart failure and atrial fibrillation, and three had "Bronze diabetes," The recommendation on the basis of the results is that well-designed clinical trials are indicated to monitor asymptomatic brain damage by magnetic resonance imaging in splenectomized patients over the age of 20 years, who are not regularly transfused and have a high risk to develop thromboembolic events. In this subset of patients, anticoagulant and/or antiplatelet therapy should be considered. Moreover, treatment of additional complications resulting from iron overload, which may contribute to the etiology of CVA such as cardiac failure and arrhythmia with or without "bronze diabetes," is mandatory.  相似文献   
536.
Most patients with Wolfram syndrome carry mutations in WFS1, while a lower percentage present a mutation in CISD2 (also known as WFS2). The aim of this study was to investigate the presence of mutations in exon 8 of WFS1 gene in two Iranian patients with Wolfram syndrome (WFS). In this study using polymerase chain reaction (PCR) followed by direct sequencing, we screened the entire length of WSF1 gene exon 8 for presence of mutations. Patients included were two male subjects who developed diabetes mellitus earlier than the age of 8 years old, showing early-onset diabetes, followed by reduced visual acuity, deafness, and diabetes insipidus. The presence of two missense mutations G736D and R629W were confirmed. These mutations have been previously reported in patients with WFS in other populations. Identification of pathogenic mutations in patients with Wolfram syndrome will be helpful in earlier diagnosis of the disease and in understanding the frequency of mutations in various populations and their relation with clinical features of Wolfram syndrome.  相似文献   
537.
Colonoscopy is an effective screening procedure in colorectal cancer prevention programs; however, colonoscopy practice can vary in terms of lesion detection, classification, and removal. Artificial intelligence (AI)-assisted decision support systems for endoscopy is an area of rapid research and development. The systems promise improved detection, classification, screening, and surveillance for colorectal polyps and cancer. Several recently developed applications for AI-assisted colonoscopy have shown promising results for the detection and classification of colorectal polyps and adenomas. However, their value for real-time application in clinical practice has yet to be determined owing to limitations in the design, validation, and testing of AI models under real-life clinical conditions. Despite these current limitations, ambitious attempts to expand the technology further by developing more complex systems capable of assisting and supporting the endoscopist throughout the entire colonoscopy examination, including polypectomy procedures, are at the concept stage. However, further work is required to address the barriers and challenges of AI integration into broader colonoscopy practice, to navigate the approval process from regulatory organizations and societies, and to support physicians and patients on their journey to accepting the technology by providing strong evidence of its accuracy and safety. This article takes a closer look at the current state of AI integration into the field of colonoscopy and offers suggestions for future research.  相似文献   
538.
α-Thalassemia (α-thal) is one of the most common genetic disorders worldwide. The aim of this study was to investigate for the first time the α-thal mutation spectrum in the Lak population living in Lorestan Province, Iran. One hundred and seventy-six α-thal carriers participated in the study. Multiplex gap-polymerase chain reaction (gap-PCR), amplification refractory mutation system (ARMS)-PCR and direct sequencing were used for the detection of different mutations on the α-globin (HBA1 and HBA2) genes. A total of 11 different mutations was identified. The –α3.7 (rightward; NG_000006.1: g.34164_37967del3804) deletion was observed most frequently (56.35%), followed by α?5?ntα (HBA2: c.95+2_95+6delTGAGG), αpolyA2α (HBA2: c.*92A>G) and – –MED I (NG_000006.1: g.24664_41064del16401), with frequencies of 15.47, 9.39, and 6.08%, respectively. These four mutations accounted for more than 87.0% of the total mutated alleles. Moreover, 19 different genotypes were identified. The types and distribution pattern of the mutations identified in this study, in comparison with other studies conducted in Iran, was most similar to the Kurdish population of Kermanshah Province, Iran. Due to the lack of information on α-thal in Lorestan Province, it was not possible to compare the mutation spectrum in the Lur and Lak populations. In conclusion, our results may help in setting up a strategy for an α-thal screening program and genetic counseling in the Lak people.  相似文献   
539.
The “Dietary Guidelines for Americans Adherence Index (DGAI) 2005” was developed based on the latest dietary recommendations to assess the contribution of dietary patterns to chronic diseases. The objective of the study was to evaluate the association of dietary patterns as measured by the modified DGAI 2005 with both the prevalence of metabolic syndrome (MetS) and the MetS risk factors. In this population-based cross-sectional study, 2504 adults (1120 men and 1384 women), aged 19 to 70 years, were randomly selected from the third phase of the Tehran Lipid and Glucose Study. Usual dietary intake was assessed using a food frequency questionnaire, and the DGAI score was calculated for all participants. Metabolic syndrome was defined according to Adult Treatment Panel III diagnostic criteria. Generally, mean values for waist circumference, triglyceride, and blood pressure were significantly higher among male compared with female participants (P < .05). Low high-density lipoprotein cholesterol was the most prevalent MetS risk factor among both men (65.4%) and women (72.5%). After mutual adjustment for confounding variables, those in the highest quartile category of DGAI had a 21% lower prevalence of MetS risk factors clustering than those in the lowest quartile (odds ratio [OR], 0.79; confidence interval [CI], 0.63-0.92; P for trend = .02). Being in the highest quartile category of DGAI score was shown to significantly reduce the prevalence of hyperglycemia (OR, 0.64; CI, 0.47-0.86; P for trend < .001), hypertension (OR, 0.76; CI, 0.70-0.93; P for trend = .05), and low high-density lipoprotein cholesterol (OR, 0.69; CI, 0.54-0.94; P for trend < .001). Consuming a diet consistent with new dietary guidelines was associated with lower risk of MetS prevalence and some of its risk factors. Preventive interventions for MetS risk reduction should focus on the overall dietary pattern.  相似文献   
540.
Background  Hereditary nonpolyposis colorectal cancer (HNPCC) is the most common cause of early onset hereditary colorectal cancer. In the majority of HNPCC families, microsatellite instability (MSI) and germline mutation in one of the DNA mismatch repair (MMR) genes are found. Materials and methods  The entire coding sequence of MMR genes (MLH1, MLH2, MLH6, and PMS2) was analyzed using direct sequencing. Also, tumor tests were done as MSI and immunohistochemistry testing. Results  We were able to find three novel MLH1 and one novel PMS2 germline mutations in three Iranian HNPCC patients. The first was a transversion mutation c.346A>C (T116P) and happened in the highly conserved HATPase-c region of MLH1 protein. The second was a transversion mutation c.736A>T (I246L), which caused an amino acid change of isoleucine to leucine. The third mutation (c.2145,6 delTG) was frameshift and resulted in an immature stop codon in five codons downstream. All of these three mutations were detected in the MLH1 gene. The other mutation was a transition mutation, c.676G>A (G207E), which has been found in exon six of the PMS2 gene and caused an amino acid change of glycine to glutamic acid. MSI assay revealed high instability in microsatellite for two patients and microsatellite stable for one patient. Conclusion  In all patients, an abnormal expression of the MMR proteins in HNPCC was related to the above novel mutations.  相似文献   
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