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71.
From January 2002 through June 2004, 17 patients (2% of all coronary cases) were treated with off-pump coronary artery bypass grafting combined with percutaneous coronary intervention. There were 13 men and 4 women, whose ages ranged from 54 to 78 years (mean, 63.1 +/- 20.9 yr). Preoperative angiography revealed 2-vessel coronary artery disease in 12 patients and 3-vessel disease in the remaining 5 patients. In all patients, extensive lesions (>50%) in the circumflex and right coronary arteries were treated first with a percutaneous intervention, followed by beating-heart coronary artery bypass grafting within 3 hours to treat the remaining obstructed vessels. Coronary angiography was performed 12 months after the operation to evaluate the effectiveness of the procedure. Procedure-related complications did not occur, and there was no in-hospital death. All patients underwent a successful left internal mammary artery-left anterior descending artery anastomosis with the exception of 1 patient, in whom we used a saphenous vein because of previous chest radiotherapy. The postoperative courses were uneventful, and no deterioration of preoperative organ dysfunction was noticed in any patient. There was no cardiac-related death or myocardial infarction. In follow-up angiography, all left internal mammary artery-left anterior descending artery anastomoses were patent. Three patients with restenosis were treated medically, which resulted in substantial reduction of angina. Hybrid coronary revascularization enables complete revascularization and may be an alternative method of treating selected patients who have concomitant disease.  相似文献   
72.
Pituitary - Non-osmotic stimulation tests using glucagon, arginine, or macimorelin were recently evaluated for their ability to assess posterior pituitary function. Glucagon and arginine, but not...  相似文献   
73.
BACKGROUND/AIMS: A significant association between variations in amino acid sequences resides between 2209-2248 nucleotides of HCV non-structural 5A (NS5A) gene, and response to interferon treatment has been proposed. The aim of this study was to determine whether the amino acid sequence changes in ISDR could be correlated to response to alpha interferon treatment in Turkish patients infected with HCV genotypes 1b and 1a. METHODS: Thirty-nine patients with chronic C virus infection (35 and 4 patients with genotype 1b and 1a, respectively), receiving 3x3-5 MU of interferon a-2b for six months were included in the study. Following PCR amplification of the region from pre-treatment serum samples, the products were directly sequenced. The amino acid sequence of NS5A was compared with the published sequence for HCV-J (AA 2209-2248). Mutant type was defined as three or more amino acid mutations, and intermediate type as 1-3 amino acids in this region. Otherwise, they were defined as the wild type (no amino acid mutations). HCV RNA serum viremia levels were analyzed by branched DNA assay. RESULTS: Eighteen patients were responders (R; 46%), whereas 21 patients were non-responders (NR; 54%). Amino acid changes in both R and NR groups did not show significant difference. Intermediate or wild type strains were detected in both groups. CONCLUSIONS: In this study, we could not determine a significant association between number of amino acid changes in NS5A2209-2248 and response to interferon treatment. In the majority of the patients, it seems that amino acid sequences in this region are well conserved.  相似文献   
74.
Cancer patients are at high risk for venous thromboembolism (VTE). Laboratory parameters with a predictive value for VTE could help stratify patients into high- or low-risk groups. The cell adhesion molecule P-selectin was recently identified as risk factor for VTE. To investigate soluble P-selectin (sP-selectin) in cancer patients as risk predictor for VTE, we performed a prospective cohort study of 687 cancer patients and followed them for a median (IQR) of 415 (221-722) days. Main tumor entities were malignancies of the breast (n = 125), lung (n = 86), gastrointestinal tract (n = 130), pancreas (n = 42), kidney (n = 19), prostate (n = 72), and brain (n = 80); 91 had hematologic malignancies; 42 had other tumors. VTE occurred in 44 (6.4%) patients. In multivariable analysis, elevated sP-selectin (cutoff level, 53.1 ng/mL, 75th percentile of study population) was a statistically significant risk factor for VTE after adjustment for age, sex, surgery, chemotherapy, and radiotherapy (hazard ratio = 2.6, 95% confidence interval, 1.4-4.9, P = .003). The cumulative probability of VTE after 6 months was 11.9% in patients with sP-selectin above and 3.7% in those below the 75th percentile (P = .002). High sP-selectin plasma levels independently predict VTE in cancer patients. Measurement of sP-selectin at diagnosis of cancer could help identify patients at increased risk for VTE.  相似文献   
75.
Hereditary juvenile megaloblastic anemia due to vitamin B12 (cobalamin) deficiency is caused by intestinal malabsorption of cobalamin. In Imerslund-Grasbeck syndrome (IGS), cobalamin absorption is completely abolished and not corrected by the administration of intrinsic factor (IF); if untreated, the disease is fatal. Biallelic mutations either in the cubilin (CUBN) or amnionless (AMN) gene cause IGS. In a series of families clinically diagnosed with likely IGS, at least six displayed no evidence of mutations in CUBN or AMN. A genome-wide search for linkage followed by mutational analysis of candidate genes was performed in five of these families. A region in chromosome 11 showed evidence of linkage in four families. The gastric IF (GIF) gene located in this region harbored homozygous nonsense and missense mutations in these four families and in three additional families. The disease in these cases therefore should be classified as hereditary IF deficiency. Clinically, these patients resembled those with typical IGS; radiocobalamin absorption tests had been inconclusive regarding the nature of the defect. In the diagnosis of juvenile cobalamin deficiency, mutational analysis of the CUBN, AMN, and GIF genes provides a molecular characterization of the underlying defect and may be the diagnostic method of choice.  相似文献   
76.
BACKGROUND: Varied vascular and biliary anatomies are common in the liver. Living donor hepatectomy requires precise recognition of the hilar anatomy. This study was undertaken to study donor vascular and biliary tract variations, surgical approaches and implications in living liver transplant patients. METHODS: Two hundred living donor liver transplantations were performed at our institution between 2004 and 2009. All donors were evaluated by volumetric computerized tomography (CT), CT angiography and magn...  相似文献   
77.
There are a number of persons with a mild to moderate bleeding tendency, in whom no underlying bleeding disorder can be detected despite thorough investigation of all known heritable and acquired haemostatic abnormalities. Thrombin is the central enzyme in the coagulation cascade, which is important for sufficient haemostasis. The measurement of an individual's potential to generate thrombin has been proposed for estimating the individual coagulation potential and predicting a hyper- or hypo-coagulable phenotype. The aim of our study was to investigate in vivo thrombin generation in a case-control study of patients with a bleeding tendency of unknown origin and in age- and sex-matched healthy individuals. Bleeding tendency was classified according to a standardized bleeding score. Thrombin generation was measured with a commercially available assay (Technothrombin-TGA, Technoclone, Vienna, Austria). In total, 101 patients (76 female; median age [25th–75th percentile], 44 [35–60] years) and 102 controls (67 women; median age, 47 [38–55] years) were enrolled. The distribution of parameters of thrombin generation among patients and controls showed no statistically significant difference: lag phase (14.4 [11.1–18.1] vs. 14.1 [12.1–17.1] min, p = 0.720), peak thrombin (179.8 [135.6–242.6] vs. 175.1 [143.1–261.4] nM, p = 0.576), time to peak thrombin (23.6 [18.1–28.6] vs. 22.6 [18.6–27.1] min, p = 0.790), velocity index (19.7 [13.0–39.0] vs. 22.6 [14.5–36.5] nM/min, p = 0.233) and area under the thrombin generation curve (3,491 [3,069–3,880] vs. 3,414 [3,045–3,750] nM thrombin, p = 0.673). In conclusion, the thrombin generation potential in patients with a bleeding tendency of unknown origin was not different from that of healthy individuals.  相似文献   
78.

Background

Aortic stenosis is one of the most commonly encountered valvular pathology requiring surgery in developed countries. There are similarities between risk factors for coronary atherosclerosis and the development of aortic stenosis. We designed a retrospective study, evaluated the lipid profile and previous echocardiographic recordings of patients with aortic stenosis, and searched the association of rate of progression and lipid profile.

Methods and results

The annual rates of progression in the peak and mean aortic gradients were 8.5 ± 3.2 and 6.7 ± 2.2 mm Hg/year, respectively. We classified the annual rate of progression of peak aortic gradient into 2 groups, group 1 with <10 mm Hg (“slow progressors”) and group 2 with ≥10 mm Hg annual rate of progression (“fast progressors”). The annual rate of progression in group 1 was significantly higher than that in group 2, both in peak and mean aortic gradients (12 ± 2 mm Hg and 6.4 ± 1.6 mm Hg; 9 ± 1.3 mm Hg and 5.2 ± 1.1 mmHg; P <.001 for both). There was a highly significant difference between group 1 and group 2 for total cholesterol/high-density lipoprotein (HDL) cholesterol level ratio (7.1 ± 1.4 vs 5.2 ± 1.3, P <.001). There was a significant correlation between annual rate of progression in peak gradient and total cholesterol/HDL cholesterol level ratio (r = 0.399, P = .009). Smoking (P = .024, Beta = 0.26), presence of coronary heart disease (P = .011, Beta = 0.31), and total cholesterol/HDL cholesterol level ratio (P = .004, Beta = 1.98) were independently predictive of fast progression of the peak aortic gradient in the regression analysis.

Conclusion

In a small group of patients from Turkey with aortic stenosis, there seems to be an association between the rate of progression and total cholesterol/HDL cholesterol level ratio, with fast progression occurring in the group with higher ratios.  相似文献   
79.
Statins have pleiotrophic effects related to the pathogenesis of atherosclerosis and thrombogenicity of the vessel wall beyond lipid lowering. The aim of the present study was to examine the effect of atorvastatin treatment on the fibrinolytic system in patients with dyslipidemia. The investigation was carried out on 41 dyslipidemic patients (21 males and 20 females) with a mean age of 53.8 years (range, 30-76). The patients were divided into subgroups according to their cholesterol and triglyceride levels as hypercholesterolemic (n = 26) and mixed-type hyperlipidemic (n = 15) and their risk factors for coronary heart disease including age, sex, hypertension, obesity, smoking, and family history. The patients were started on atorvastatin 10 mg/day, and evaluated within 6-12 weeks to assess the changes in fibrinolytic parameters including global fibrinolytic capacity, plasminogen activator inhibitor type-1 and tissue plasminogen activator, and lipids. After successful lipid-lowering therapy, global fibrinolytic capacity (P = 0.003) and tissue plasminogen activator levels (P = 0.04) were found to be increased and plasminogen activator inhibitor type-1 levels (P = 0.02) decreased in dyslipidemic patients. Global fibrinolytic capacity levels increased (P < 0.001) and plasminogen activator inhibitor type-1 levels decreased (P = 0.01) in patients with hypercholesterolemia (n = 26). However, no significant changes were observed in fibrinolytic parameters in patients with mixed-type hyperlipidemia (n = 15). When the patients were separately evaluated according to risk factors, significant beneficial effects on the fibrinolytic system were observed, especially in patients without obesity and hypertension as well as in older patients and males. These findings suggest that atorvastatin treatment has a beneficial effect on the fibrinolytic system in patients with hypercholesterolemia, but not in patients with mixed-type hyperlipidemia. Further studies are needed to show whether higher doses and longer periods of lipid lowering treatment have beneficial effects in patients with mixed type hyperlipidemia and some risk factors.  相似文献   
80.
BACKGROUND: The aim of the study was to investigate the effects of a long term (1 year) hormone replacement therapy (HRT) on QT interval, QT dispersion (QTd) frequencies of arrhythmia and heart rate variability (HRV) parameters. METHODS: Forty-six healthy postmenopausal women (mean age; 55.34+/-4.21) as a hormone replacement therapy group and 25 healthy premenopausal women (mean age; 35.36+/-6.06) as a control group were prospectively enrolled to the study. Hormone replacement therapy group was divided into two groups; estrogen replacement therapy (ERT) group (n=23) and progestin-estrogen replacement therapy (PERT) group (n=23). Standard 12 lead electrocardiograms and 24-h ambulatory Holter recording were obtained to evaluate the effects of one year of ERT and PERT on QT intervals, QTd, frequencies of arrhythmias and HRV parameters. RESULTS: Long term use of ERT increases QT interval, QTd, in the frequencies of arrhythmia and HRV indexes of parasympathetic activity; however, the increase in frequencies of arrhythmia was not statistically significant (p>0.05). Long term use of PERT did not effected QT interval, QTd, frequencies of ventricular arrhythmia and HRV parameters (p>0.05). Frequency of supraventricular tachycardia increased in post-treatment PERT group was compared with pre-treatment PERT group. CONCLUSION: These findings supported the hypothesis that estrogen may directly modulate ventricular repolarization. But progestin do not effect the ventricular repolarization. However, these findings must be supported with a large-scale study.  相似文献   
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