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Diffusion tensor tractography (DTT) is useful for exploring the state of the corticospinal tract (CST). An accurate estimation of the integrity of the CST in the early stage of a cerebral infarct would enable a determination of motor recovery. DTT was performed to classify CST integrity following a corona radiata infarct to evaluate if the procedure could characterize the motor outcome of the affected hand. Fifty-five patients with completely paralyzed hands due to a corona radiata infarct were recruited for the study, and DTT images were obtained within 7–30 days after a stroke. The DTI findings for the patients were classified into four groups. In type A, the CST was preserved around the infarct; in type B, the CST originated from a cortex other than the primary motor cortex; in type C, the CST was interrupted at the infarct; in type D, the CST failed to reach the infarct due to degeneration. Six months after a stroke, the motor function of the affected hand was evaluated with the motricity index (MI) for the hand, the Medical Research Council score (MRC) for finger extensors and the modified Brunnstrom classification (MBC). These indices were significantly influenced by the DTT type (p < 0.05). The highest MI, MRC and MBC were seen in the DTT type A patients; the lowest MI, MRC and MBC were seen in the DTT type D patients (p < 0.05). The integrity of the corticospinal tract determined by DTT obtained during the early stage of a corona radiata infarct seems to be helpful in predicting the motor outcome of the affected hand.  相似文献   
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A series of 20 hepatocellular carcinomas and 8 intrahepatic cholangiocarcinomas was screened from the Korean population for microsatellite alterations, including a loss of heterozygosity and replication errors using nine microsatellite markers containing several genes. The microsatellite results and our previous comparative genomic hybridization results of two tumors were compared at each locus, and the correlations between these and clinicopathologic variables were examined. The most characteristic findings were found at 13q. Replication errors were prevalent at D13S160 (13q21.2 approximately q31) and D13S292(13q12). The incidence of loss of heterozygosity, however, was higher at D13S153 (13q14.1 approximately q14.3) and D13S265(13q31 approximately q32). In contrast, there were higher deletion frequencies observed in hepatocellular carcinoma (HCC) and higher amplification frequencies observed in intrahepatic cholangiocarcinoma at 13q in our previous comparative genomic hybridization (CGH) study. Higher frequencies of replication errors were observed at D16S408 (13q12 approximately q21) and D16S504(13q23 approximately q24) in the HCC. This study found that significant differences in the patterns of genetic instability of microsatellites were dependent on the chromosomal loci. It is believed that certain genes at altered CGH regions, which are relevant to the development and/or progression of these cancers, are activated by different mutation mechanisms.  相似文献   
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Complete occlusion of the left main coronary artery is considered to be a terminal event in most cases. We describe two patients with this lesion who underwent successful coronary bypass surgery with complete relief of symptoms and long-term survival. The angiographic findings and clinical management of the two patients are discussed.  相似文献   
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The chronic cerebral retinal insufficiency syndrome in elderly patients is an organ specific expression of a generalized vascular cerebral deficiency. The progress of the disease is characterized by complex symptoms, variation in course, spontaneous remissions and, until recently inadequate diagnostic measurement methods. The new method of automated perimetry with the octopus 2000 P offers a patient-friendly procedure for indirect non-invasive diagnosis of circulatory state in limited cerebral retinal perfusion. In the present study measurements were made with this method on 24 patients (4 men and 20 women with an age of 74.9 +/- 6.9 years). The effect of the extract of Ginkgo biloba (EGb 761) on the reversibility of visual field disturbances was tested using a randomized and double blind study-design in two phases and with two dose levels. The main parameter investigated in this study was the change in the luminous density difference threshold after therapy with EGb 761. In group B (EGb 761 dose 160 mg/day) a significant increase in retinal sensitivity was seen within 4 weeks (p less than 0.05). In the lower dose (80 mg EGb 761/day) group (A), this change in retinal sensitivity was first seen after increasing the dose to 160 mg/day (p less than 0.01). The relative sensitivity of damaged retinal areas was more strongly influenced than "healthy" areas. The assessment by both doctors and patients of the general condition of the patients showed a significant improvement after the course of therapy. The results presented here show that damage to the visual field by chronic lack of bloodflow are significantly reversible.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Background and aimsWomen with obesity are highly predominant among patients with heart failure with preserved ejection fraction (HFpEF). We aimed to elucidate sex-specific associations of obesity with exercise capacity and diastolic function.Methods and resultsHealthy individuals without known cardiovascular diseases undergoing cardiopulmonary exercise test and echocardiography (n = 736) were included and categorized into 4 groups according to their sex and obesity. Exercise capacity was lower in women than men. Obesity was associated with a lower exercise capacity in women (23.5 ± 7.3 vs. 21.3 ± 5.4 ml/kg/min, p < 0.05) but not in men (28.2 ± 7.8 vs. 28.0 ± 6.6 ml/kg/min, p > 0.10). Overall, women had a higher E/e′ than men. Women without obesity had a similar E/e′ to men with obesity (8.2 ± 1.8 vs. 8.4 ± 2.1, p > 0.10), and women with obesity had the highest E/e′. Among 5 risk factors (aging, obesity, elevated blood pressure, elevated heart rate, and elevated fasting glucose), obesity was a significant determinant of exercise intolerance in women but not men. Furthermore, obesity was associated with a greater risk of diastolic dysfunction in women than men (women, adjusted odds ratio 4.35 [95% confidence interval 2.44–7.74]; men, adjusted odds ratio 2.91 [95% confidence interval 1.42–5.95]).ConclusionObesity had a more deleterious effect on exercise capacity and diastolic function in women than men, even in a healthy cohort. These subclinical changes might contribute to the development of a female predominance among HFpEF patients, particularly among individuals with obesity.  相似文献   
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Patients with thymoma are likely to present with associated autoimmunologic disorders. The occurrence of syndrome of inappropriate antidiuretic hormone (SIADH) attributable to thymoma is extremely rare. We herein present an extremely rare case of a 59-year-old man patient who was discovered to have malignant thymoma associated with myasthenia gravis, Graves' disease, and SIADH. He was admitted for evaluation and treatment of hyponatremia (Na 125 mEq/l). SIADH was diagnosed, and thymoma was identified as its cause. The patient was also found to have both Graves' disease and myasthenia gravis. The hyponatremia was normalized with water restriction and 3% saline therapy before thymectomy. The thymic tumor was a Masaoka stage III thymoma that resulted in direct invasion to the wall of the innominate vein, but there was no finding of invasion to other mediastinal organs. Complete thymectomy with innominate vein graft was performed. Microscopic histopathology findings corresponded to those of a mixed-type thymoma and type B2. However, immunohistochemical stain for antidiuretic hormone was negative in the tumor cells. Adjuvant radiation therapy was employed postoperatively, and the patient's postoperative recovery was uneventful. He subsequently reached a euthyroid state. And the reversal to normal sodium and osmolality levels was continued after the tumor removal without any further management for hyponatremia. The observation of this interesting case and a literature review provided us with the opportunity to explore the pathogenesis and clinical aspects of thymoma-related autoimmune and/or endocrine disorders which must be suspected in patients with thymoma.  相似文献   
9.
BACKGROUND: It has been recently suggested that gamma-glutamyltransferase (GGT) is independently associated with cardiovascular mortality and atherosclerosis, so the present study evaluated whether GGT is an additional marker of arterial stiffness, independent of other risk factors, in screening cohorts. METHODS AND RESULTS: The 1,387 individuals (741 men, 646 women) who underwent brachial - ankle pulse wave velocity (baPWV) measurement had their serum levels of GGT, creatinine, uric acid, C-reactive protein, lipids, fasting glucose and insulin, and their hepatitis profiles checked. There were statistically significant increments of baPWV according to quartile of GGT, which was statistically significant in women, but not in men. In logistic regression analysis, age, diabetes mellitus, GGT, heart rate, history of hypertension, triglyceride, and systolic blood pressure were significant variables that influenced increased pulse wave velocity (PWV). After age-and blood pressure-adjustment, GGT, homeostatic model assessment-insulin resistance, heart rate, history of hypertension, and metabolic syndrome were significant variables in men, and in women metabolic syndrome and history of hypertension were significant contributors to increased PWV. CONCLUSION: The present study results suggest that serum GGT may be an additional marker of arterial stiffness, especially in men, though the relationship with arterial stiffness was very weak. Further studies are needed to elucidate the mechanism of GGT's contribution to arteriosclerosis and to confirm the current results.  相似文献   
10.
The multidrug resistance-associated protein (MRP1) mediates cellular efflux of various xenobiotics and cellular resistance to heavy metals. Previously we reported that MRP1 mediates resistance to mercury exposure and possible mechanism mediating MRP1 expression after mercury exposure. This study was designed to investigate the role of reactive oxygen species (ROS) and glutathione on the resistance of AML-2/DX100 cells to mercuric chloride. The MRP1 overexpressing cells (AML-2/DX100) cells showed less scavenging activity to ROS induced by mercury while no difference in the basal glutathione levels between AML-2/WT and AML-2/DX100 cells. Mercury induced the activation of p38 mitogen-activated protein kinase (MAPK) and extracellular signal-regulated kinase (ERK) but not c-jun-N-terminal kinase in AML-2/DX100 cells. The specific inhibitor for p38 MAPK and ERK, and antioxidant decreased the production of MRP1 and therefore resistance of AML-2/DX100 cells against mercury exposure. These results suggest that induction of ROS and downstream p38 MAPK and ERK were involved in the resistance of cells to mercury by expression MRP1 in AML-2/DX100 cells.  相似文献   
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