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91.

Background

An upper limb arteriovenous (AV) fistula is the access of choice for haemodialysis (HD). There have been few reports of saphenofemoral AV fistulas (SFAVF) over the last 10-20 years because of previous suggestions of poor patencies and needling difficulties. Here, we describe our clinical experience with SFAVF.

Methods

SFAVFs were evaluated using the following variables: immediate results, early and late complications, intraoperative and postoperative complications (up to day 30), efficiency of the fistula after the onset of needling and complications associated to its use.

Results

Fifty-six SFAVF fistulas were created in 48 patients. Eight patients had two fistulas: 8 patent (16%), 10 transplanted (20%), 12 deaths (24%), 1 low flow (2%) and 20 thrombosis (39%) (first two months of preparation). One patient had severe hypotension during surgery, which caused thrombosis of the fistula, which was successfully thrombectomised, four thrombosed fistulae were successfully thrombectomised and revised on the first postoperative day. After 59 months of follow-up, primary patency was 44%.

Conclusion

SFAVF is an adequate alternative for patients without the possibility for other access in the upper limbs, allowing efficient dialysis with good long-term patency with a low complication rate.  相似文献   
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The objective of this clinical study was to determine the real frequency and clinical importance of partial obstruction of the seminal path in patients with oligozoospermia. We have designed a prospective clinical study including men with oligozoospermia seen at an andrological consultation in both private and institutional hospitals. A testicular biopsy was done on all patients under local anaesthesia. A complete study for sterility was also done [hormonal determinations: follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone, testicular ultrasound, semen analysis, testicular Doppler ultrasound, etc.]. We have made a quantitative and qualitative evaluation of testicular biopsy (percentage of tubules with Sertoli cell only or with hyalinization; mean tubular diameter; number of spermatogonia, primary spermatocytes, young spermatids, mature spermatids and Sertoli cells; and evaluation of testicular interstitium: number of Leydig cell clusters, presence of angiectasis, presence of perivascular inflammation). Sixty one per cent of all oligozoospermia cases were obstructive. The principal cause of obstructive oligozoospermia was the presence of testicular varicocele. In obstructive oligozoospermia, the tubular diameter and number of mature spermatids are statistically significantly higher than in non- obstructive oligozoospermia. Obstructive oligozoospermia is a frequent condition caused by partial obstruction of seminal path. A quantitative analysis of the testicular biopsy is the only method of diagnosis.   相似文献   
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Trends in pedestrian injury mortality for children aged 0-4 and 5-14 for England and Wales, Denmark, Sweden, the USA, and New Zealand were examined from 1968 onwards. While there has been a reduction in the pedestrian mortality in all these countries, there are striking international differences in the extent of these reductions. Denmark has achieved the greatest fall in mortality with the smallest decrease seen in New Zealand. Countries which have experienced major decreases in pedestrian mortality are distinguished by having placed greater emphasis on environmentally based prevention strategies rather than pedestrian skills education.  相似文献   
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Background Recent observations established the role of altered cellular immunity and autoimmune hypothesis in the pathogenesis of vitiligo. There have been several reports discussing T‐cell and natural killer (NK) cell populations, but NK cell receptors were not evaluated in vitiligo. Objective The purpose of this investigation was to assess the role of T and NK cells as well as activatory and inhibitory NK cell receptor alterations in the pathogenesis of vitiligo and whether any aberrations were correlated with clinical findings of the disease. Patients/methods Fifty‐three patients with non‐segmental vitiligo and 45 age‐ and sex‐matched healthy controls were enrolled in the study. The percentages of lymphocytes, granulocytes, monocytes and CD3, CD4, CD8, CD14, CD16, CD56, CD45, CD45RA, CD54RO, CD28, CD80, CD94, CD158a, KIR3DL‐1 receptors as well as CD94, CD158a, KIR3DL‐1 receptors on CD16+ cells were detected by using flow cytometry. The patient and control groups were compared in terms of the results of flow cytometric analysis, and the results were assessed regarding the type and activity of vitiligo. Results The percentages of CD16+CD56+, CD3+CD16+CD56+, CD8+ and CD45RO+ cells were significantly increased in vitiligo group compared with the controls. No difference was detected between the patients and control groups in percentages of CD3+, CD4+, CD3?CD16+CD56+, CD28+, CD45+, CD45RA+, CD94+, CD158a+ and KIR3DL‐1+ cells. The percentage of CD16+CD158a+ cells was significantly decreased in a randomized selected group of vitiligo patients. There were no differences in percentage expression of studied cell surface antigens between patients in the active or stable period. CD3+ cells were significantly increased in generalized form, and CD45RO+ cells were significantly increased in acral/acrofacial form when compared with the other types of vitiligo. Conclusions These results indicate further evidence for T and NK cell abnormalities in non‐segmental vitiligo. The present data show that NK cell activation may be responsible in the pathogenesis of vitiligo in conformity with decreased inhibitory and increased activatory NK cell receptors.  相似文献   
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The use of integrated visualization for medical images aims at assisting clinicians in the difficult task of mentally translating and integrating medical image data from multiple sources into a three-dimensional (3D) representation of the patient. This interpretation of the enormous amount and complexity of contemporary, multiparameter, and multimodal image data demands efficient methods for integrated presentation. This article reviews methods for fused display with the main focus on integration of functional with anatomical images. First, an overview of integrated two-dimensional (2D) and 3D medical image display techniques is presented, and topics related to the interpretation of the integrated images are discussed. Then we address the key issue for clinical acceptance, ie, whether these novel visualization techniques lead to diagnostic improvements. Methods for fused display appear to be powerful tools to assist the clinician in the retrieval of relevant information from multivariate medical image data. Evaluation of the different methods for fused display indicates that the diagnostic process improves, notably as concerns the anatomical localization (typically of functional processes), the registration procedure, enhancement of signal, and efficiency of information presentation (which increases speed of interpretation and comprehension). Consequently, fused display improves communication with referring specialists, increases confidence in the observations, and facilitates the intra- and intersubject comparison of a large part of the data from the different sources, thereby simplifying the extraction of additional, valuable information. In most diagnostic tasks the clinician is served best by providing several (interactive and flexible) 2D and 3D methods for fused display for a thorough assessment of the wealth of image information from multiple sources.  相似文献   
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PURPOSE: Statistical parametric mapping (SPM) is an image-analysis tool that assesses the statistical significance of cerebral blood flow (CBF) changes on a voxel-by-voxel basis, thereby removing the subjectivity inherent in conventional region-of-interest (ROI) analysis. Our platform of single-photon emission computed tomography (SPECT) ictal-interictal difference imaging in clinical epilepsy has been validated for localizing seizure onset. We extend the tools of SPM by further applying statistical measures for the significance of perfusion changes in individual patients to localize epileptogenic foci in patients with defined temporal lobe epilepsy by using paired scans in this preliminary study. METHODS: Twelve patients with pairs of periictal and interictal SPECT scans were analyzed in this comparison study between SPECT difference imaging and SPM difference analysis by using a reference database of paired normal healthy images. These 12 patients possessed seizure foci localized to the mesial temporal lobe as confirmed by surgical outcome and by hippocampal sclerosis on pathology. SPM was used to identify clusters of increased or decreased CBF in each patient in contrast to our control group. RESULTS: The regions having the most significant increased or decreased CBF by SPM analysis were in agreement with regions identified by conventional difference imaging and visual analysis by viewers blinded to the results of the SPM analysis. Differentiated further by time of radiopharmaceutical injection, six of seven patients injected within 100 s of seizure onset displayed hyperperfusion changes localized to the corresponding epileptogenic temporal lobe by both techniques. Among patients receiving injections after 100 s, both techniques showed primarily regions of hypoperfusion, which again were similar between these two methods. CONCLUSIONS: The results provide strong evidence supporting SPM difference analysis in assessing regions of significant CBF change from baseline in concordance with our current clinically used technique of SPECT ictal--interictal difference imaging in epilepsy patients. Difference analysis using SPM could serve as a useful diagnostic tool in the evaluation of seizure focus in temporal lobe epilepsy.  相似文献   
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