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41.
The division of breast cancer cells results in regions of electrical depolarisation within the breast. These regions extend to the skin surface from where diagnostic information can be obtained through measurements of the skin surface electropotentials using sensors. This technique is used by the Biofield Diagnostic System (BDS) to detect the presence of malignancy. This paper evaluates the efficiency of BDS in breast cancer detection and also evaluates the use of classifiers for improving the accuracy of BDS. 182 women scheduled for either mammography or ultrasound or both tests participated in the BDS clinical study conducted at Tan Tock Seng hospital, Singapore. Using the BDS index obtained from the BDS examination and the level of suspicion score obtained from mammography/ultrasound results, the final BDS result was deciphered. BDS demonstrated high values for sensitivity (96.23%), specificity (93.80%), and accuracy (94.51%). Also, we have studied the performance of five supervised learning based classifiers (back propagation network, probabilistic neural network, linear discriminant analysis, support vector machines, and a fuzzy classifier), by feeding selected features from the collected dataset. The clinical study results show that BDS can help physicians to differentiate benign and malignant breast lesions, and thereby, aid in making better biopsy recommendations.  相似文献   
42.
Intracranial Hodgkin lymphoma (HL) is considered so atypical that an intracranial space‐occupying lesion in a patient with known HL should be thoroughly investigated to rule out a second disease process.  相似文献   
43.
In the case of carotid atherosclerosis, to avoid unnecessary surgeries in asymptomatic patients, it is necessary to develop a technique to effectively differentiate symptomatic and asymptomatic plaques. In this paper, we have presented a data mining framework that characterizes the textural differences in these two classes using several grayscale features based on a novel combination of trace transform and fuzzy texture. The features extracted from the delineated plaque regions in B-mode ultrasound images were used to train several classifiers in order to prepare them for classification of new test plaques. Our CAD system was evaluated using two different databases consisting of 146 (44 symptomatic to 102 asymptomatic) and 346 (196 symptomatic and 150 asymptomatic) images. Both these databases differ in the way the ground truth was determined. We obtained classification accuracies of 93.1 and 85.3 %, respectively. The techniques are low cost, easily implementable, objective, and non-invasive. For more objective analysis, we have also developed novel integrated indices using a combination of significant features.  相似文献   
44.
Quantitative characterization of carotid atherosclerosis and classification into symptomatic or asymptomatic type is crucial in both diagnosis and treatment planning. This paper describes a computer-aided diagnosis (CAD) system which analyzes ultrasound images and classifies them into symptomatic and asymptomatic based on the textural features. The proposed CAD system consists of three modules. The first module is preprocessing, which conditions the images for the subsequent feature extraction. The feature extraction stage uses image texture analysis to calculate Standard deviation, Entropy, Symmetry, and Run Percentage. Finally, classification is performed using AdaBoost and Support Vector Machine for automated decision making. For Adaboost, we compared the performance of five distinct configurations (Least Squares, Maximum- Likelihood, Normal Density Discriminant Function, Pocket, and Stumps) of this algorithm. For Support Vector Machine, we compared the performance using five different configurations (linear kernel, polynomial kernel configurations of different orders and radial basis function kernels). SVM with radial basis function kernel for support vector machine presented the best classification result: classification accuracy of 82.4%, sensitivity of 82.9%, and specificity of 82.1%. We feel that texture features coupled with the Support Vector Machine classifier can be used to identify the plaque tissue type. An Integrated Index, called symptomatic asymptomatic carotid index (SACI), is proposed using texture features to discriminate symptomatic and asymptomatic carotid ultrasound images using just one index or number. We hope this SACI can be used as an adjunct tool by the vascular surgeons for daily screening.  相似文献   
45.
Double aortic arch (DAA) is a congenital vascular anomaly. The diagnosis was difficult till the child was symptomatic, and other causes were ruled out. We present the interesting images of a child of respiratory distress because of tracheal compression from DAA.  相似文献   
46.
The aim of this study was to investigate the relationship between total homocysteine levels in people with Type 2 diabetes and cognitive status. Fifty patients from our diabetes unit (30 females/20 males) with diabetes were enrolled. All patients had fasting blood samples taken for measurement of cardiovascular risk factors; total cholesterol and triglyceride concentrations and other lipid fractions (lipoprotein (a), low density lipoprotein (LDL-cholesterol), high density lipoprotein (HDL-cholesterol)), glucose, HbA(1c) and homocysteine. 24-h urine collection was used to measure creatinine clearance and microalbuminuria. Vitamin B-12 and folate were measured to assess vitamin status. All diabetic patients were assessed for late complications and a Mini-Mental State Examination (MMSE) was performed. The patients were 64.6 (49-78) years old with body mass index (BMI) of 29.6 +/- 6.3 kg/m(2), and duration of diabetes of 8.9 +/- 6.7 years. A univariant correlation analysis was performed among cardiovascular risk factors and vitamins with total MMSE score. Total homocysteine was inverse by correlated with MMSE score (r=-0.38; P<0.05) of the other measures of cardiovascular risk, microalbuminuria showed an inverse correlation with MMSE score (r=-0.51:P<0.01). Lipoproteins, glucose control and vitamin status were not correlated MMSE score. In the multiple regression model only microalbuminuria remained in the model, showing a decrease of one point in the MMSE result with each milligram of microalbuminuria, adjusted for confounding factors. Cognitive status in type 2 diabetic was correlated with homocysteine levels and microalbuminuria, this last endothelial damage marker remaining as an independent risk factor of cognitive deterioration.  相似文献   
47.
In utero ethanol exposure elicits apoptotic cell death in the fetal brain, and this may be mediated by oxidative stress. Our studies utilize cultured fetal rat cortical neurons and illustrate that ethanol elicits a rapid onset of oxidative stress, which culminates in mitochondrially mediated apoptotic cell death. Cells exposed to ethanol (2.5 mg/ml) remained attached to their polylysine matrix during a 24-hr exposure, but they exhibited distinct signs of oxidative stress, decreased viability, and apoptosis. Confocal microscopy of live cortical neurons pretreated with dichlorodihydrofluorescein diacetate demonstrated an increase in reactive oxygen species (ROS) within 5 min of ethanol exposure. The levels of ROS further increased by 58% within 1 hr (P <.05) and by 82% within 2 hr (P <.05), accompanied by increases of mitochondrial 4-hydroxynonenal (HNE). These early events were followed by decreased trypan blue exclusion of 10% to 32% (P <.05) at the 6- to 24-hr time points, respectively. This culminates in apoptotic death, with increases of Annexin V binding of 43%, 89%, 123%, and 238%, at 2, 6, 12, and 24 hr of ethanol treatment, respectively, as well as DNA fragmentation increases of 50% and 65% by 12 and 24 hr, respectively. Release of cytochrome c by mitochondria increased by 53% at 6 hr of exposure (P <.05), concomitant with activation of caspase 3 (52% at 12 hr, P <.05). Pretreatment with N-acetylcysteine increased cellular glutathione and prevented apoptosis. These studies provide a time line illustrating that oxidative stress and formation of a proapoptotic lipid peroxidation product, HNE, precede a cascade of mitochondrially mediated events in cultured fetal cortical neurons, culminating in apoptotic death. The prevention of apoptosis by augmentation of glutathione stores also strongly supports a role for oxidative stress in ethanol-mediated apoptotic death of fetal cortical neurons.  相似文献   
48.
49.
An in vitro cell line model was established to exemplify tumor stem cell concept in oral cancer. We were able to identify CD147 expressing fractions in SCC172 OSCC cell line with differing Hoechst dye efflux activity and DNA content. In vivo tumorigenic assay revealed three fractions enriched with stem-like cells capable of undergoing mesenchymal transition and a non-tumorigenic fraction. The regeneration potential and transition of one fraction to other imitated the phenotypic switch and functional disparities evidenced during oral tumor progression. Knowledge of these additional stem-like subsets will improve understanding of stem cell based oral epithelial tumor progression from normal to malignant lesions.  相似文献   
50.
We report prospective clinical and radiographic outcomes of a series of 219 hydroxyapatite-coated Duracon (Stryker Howmedica Osteonics Corporation, Kalamazoo, Mich) total knee arthroplasties with a follow-up of 5 to 8 years. Knee Society Score, Western Ontario and McMaster Universities Osteoarthritis index (WOMAC), and SF-12 Health Status Questionnaire were used. Analysis of fluoroscopic radiographs was performed with the American Knee Society Score. All living patients (186 knees) were followed up. Twenty-eight patients (30 knees) had died. The preoperative Knee Society Score of 43.8 increased to 77.1 and the preoperative Function score of 20.3 increased to 63.4. WOMAC scores showed marked improvement (pain, 250 preoperatively to 157; stiffness, 115 preoperatively to 56; and function, 910 preoperatively to 588). There was no radiographic evidence of loosening or migration. Gaps visible at the bone-implant interface healed over the first year. Three prostheses were revised, 2 for deep infection and 1 for tibial tray subsidence. A survivorship of 98.6% has been achieved at 8 years. This intermediate-term study with 100% follow-up at 8 years demonstrates excellent clinical and radiographic outcomes. It is our opinion that these are comparable to the gold standard cemented total knee arthroplasties and may have advantages over other uncoated cementless designs.  相似文献   
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