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Background

False-negative myocardial perfusion imaging (MPI) can by due to left main (LM) or three-vessel disease causing “balanced ischemia”. However, so far prevalence of LM or three-vessel-disease in patients with normal MPI is unclear. We assessed prevalence, location, and extent of significant coronary artery disease (CAD) in patients with normal MPI.

Methods

Between 2006 and 2010, 256 patients with normal MPI who had invasive angiography because of persisting or worsening of the same initial symptoms were studied. Significant CAD was defined as stenosis > 70% or LM > 50%.

Results

A total of 93 patients (36%) had significant CAD. Significant CAD was observed more frequently in males, higher age and those with typical angina complaints. Significant LM disease was present in 7%, three-vessel disease in 10%, two-vessel disease in 22%, and single vessel disease (not left main) in 61%. In those with single vessel disease, the location was the LAD in 40%, the RCA in 30%, and the LCX in 30%.

Conclusions

In selected patients with normal MPI, one-third had significant CAD. The majority of these patients had single vessel disease (not left main). LM or three vessel disease, causing “balanced ischemia”, is a less common cause of false-negative MPI.  相似文献   
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OBJECTIVE: Detection of congenital urinary system anomalies is an important part of the prenatal ultrasound examination. The present study compares prenatal ultrasonographic findings and postmortem examinations of fetuses and infants with renal and urinary tract anomalies. DESIGN: Criteria for inclusion were an ultrasound examination at the National Center for Fetal Medicine (Trondheim, Norway) and autopsy performed during the period 1985-94. Results from the ultrasound examination and autopsy regarding urinary system anomalies were categorized according to the degree of concordance. RESULTS: Urinary system anomalies were found in 112 (27%) of 408 fetuses with congenital anomalies. The renal and/or urinary tract anomaly was the principal reason for induced abortion or cause of death in 50 cases (45%). In 97 (87%) of the 112 cases there was full agreement between the ultrasound observations and the autopsy findings. In five cases the autopsy revealed minor findings not mentioned in the ultrasound report. The main diagnosis was thus correct in 102 cases (91%). In four cases major autopsy findings had not been found by ultrasound examination; in another four, none of the autopsy findings were suspected by ultrasound, and in two, minor ultrasound findings were not confirmed at autopsy. CONCLUSIONS: The accordance between ultrasound diagnoses and postmortem examinations proved to be satisfactory. The close co-operation between ultrasonographers and perinatal pathologists is mutually beneficial. In addition to complementing prenatal diagnosis, postmortem examination is of vital importance for the quality control of ultrasonography in fetal diagnosis and plays an important role in genetic counseling.  相似文献   
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Standardization of the display of ultrasound images has so far only been achieved in transabdominal two-dimensional (2D) sonography. In contrast, there is a lack of uniformity in the demonstration of transvaginal 2D ultrasound images. The described non-uniformity frequently leads to confusion in the assessment of an image, in particular with regard to the accurate anatomical assignment of left/right and dorsal/ventral. Three-dimensional (3D) sonography offers a unique opportunity to avoid this confusion in the interpretation of ultrasound images, because, independent of primary volume acquisition, the volume can always be rotated so that the stored object can at all times be visualized in a known anatomical position, rendering it of no importance whether the image acquired transvaginally is demonstrated from above or from below. This will also be important in allowing fusion of ultrasound image data with computed tomographic, magnetic resonance and/or positron emission tomography images. In this article we suggest that standardization of transabdominal and transvaginal 3D images does not only provide the inexperienced physician/sonographer with a guide to spatial orientation, but also serves to avoid erroneous topographical interpretations.  相似文献   
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Journal of Neurology - Hereditary spastic paraplegia (HSP) is characterized by a bilaterally spastic gait pattern. During gait, increased trunk movements are often observed. People with HSP likely...  相似文献   
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BACKGROUND: There is growing evidence for a clinical benefit of primary percutaneous coronary intervention (PCI) compared with fibrinolysis; however, whether the treatment effect is consistent among patients with diabetes mellitus is unclear. We compared PCI with fibrinolysis for treatment of ST-segment elevation myocardial infarction in patients with diabetes mellitus. METHODS: A pooled analysis of individual patient data from 19 trials comparing primary PCI with fibrinolysis for treatment of ST-segment elevation myocardial infarction was performed. Trials that enrolled at least 50 patients with ST-segment elevation myocardial infarction and randomized patients to receive either primary PCI or fibrinolysis were considered for inclusion in our study. Clinical end points were total deaths, recurrent infarction, death or nonfatal recurrent infarction, and stroke, measured 30 days after randomization. RESULTS: Of 6315 patients, 877 (14%) had diabetes. Thirty-day mortality (9.4% vs 5.9%; P < .001) was higher in patients with diabetes. Mortality was lower after primary PCI compared with fibrinolysis in both patients with diabetes (unadjusted odds ratio, 0.49; 95% confidence interval, 0.31-0.79; P = .004) and without diabetes (unadjusted odds ratio, 0.69; 95% confidence interval, 0.54-0.86, P = .001), with no evidence of heterogeneity of treatment effect (P = .24 for interaction). Recurrent infarction and stroke were also reduced after primary PCI in both patient groups. After multivariable analysis, primary PCI was associated with decreased 30-day mortality in patients with and without diabetes, with a point estimate of greater benefit in diabetic patients. CONCLUSIONS: Diabetic patients with ST-segment elevation myocardial infarction treated with reperfusion therapy have increased mortality compared with patients without diabetes. The beneficial effects of primary PCI compared with fibrinolysis in diabetic patients are consistent with effects in nondiabetic patients.  相似文献   
30.

Ethnopharmacological relevance

Enslaved Africans in the Americas had to reinvent their medicinal flora in an unknown environment by adhering to plants that came with them, learning from Amerindians and Europeans, using their Old World knowledge and trial and error to find substitutes for their homeland herbs. This process has left few written records, and little research has been done on transatlantic plant use. We used the composition of aphrodisiac mixtures across the black Atlantic to discuss the adaptation of herbal medicine by African diaspora in the New World. Since Africans are considered relatively recent migrants in America, their healing flora is often said to consist largely of pantropical and cultivated species, with few native trees. Therefore, we expected Caribbean recipes to be dominated by taxa that occur in both continents, poor in forest species and rich in weeds and domesticated exotics.

Materials and methods

To test this hypothesis, we compared botanical ingredients of 35 African and 117 Caribbean mixtures, using Dentrended Correspondence Analysis, Cluster Analysis, Indicator Species Analysis and Mann–Whitney U tests.

Results

Very few of the 324 ingredients were used on both continents. A slightly higher overlap on generic and family level showed that Africans did search for taxa that were botanically related to African ones, but largely selected new, unrelated plants with similar taste, appearance or pharmacological properties. Recipes from the forested Guianas contained more New World, wild and forest species than those from deforested Caribbean islands. We recorded few ‘transatlantic genera’ and weeds never dominated the recipes, so we rejected our hypothesis.

Conclusions

The popularity of bitter tonics in the Caribbean suggests an African heritage, but the inclusion of Neotropical species and vernacular names of plants and mixtures indicate Amerindian and European influence. We show that enslaved Africans have reinvented their herbal medicine wherever they were put to work, using the knowledge and flora that was available to them with great creativity and flexibility. Our analysis reveals how transplanted humans adapt their traditional medical practises in a new environment.  相似文献   
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