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An ex-vivo test was used to evaluate the activity of antimicrobials against three microorganisms, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus. The ex-vivo test is a carrier test using freshly excised animal skin samples maintained in viable conditions for a short period of time. Skin samples came from a veterinary practice and were excised from either dogs or cats. The antimicrobial activity of povidone iodine, chlorhexidine diacetate, cetrimide and benzalkonium chloride was also evaluated with suspension and glass-carrier tests. Generally, the activity of the antimicrobials tested was reduced when applied to the skin surface. Apart from povidone iodine (2%) against S. aureus, the biocides investigated failed to achieve a 5 log10 reduction in bacterial titre when tested with the ex-vivo method. There was no significant difference in reduction of bacterial titres after treatment with antimicrobials between the glass-carrier and the suspension tests. Furthermore, the drying process of bacterial inoculum was less detrimental on skin than on glass surfaces. This study confirmed that the activity of a biocide tested in suspension or on an inanimate surface did not reflect its activity when tested on skin. Further development of the ex-vivo test may be useful, especially for testing the antimicrobial activity of formulations with antiseptic properties.  相似文献   
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To determine whether high dietary selenium intake was associated with adverse effects, selenium in diet, blood, and toenails was studied in relation to human health in adults residing in western South Dakota and eastern Wyoming. Over a 2-y period 142 subjects were recruited from households selected at random and from ranches where unusually high selenium intakes were suspected. Subjects completed health questionnaires, underwent physical examinations, provided blood samples for clinical assessment, and provided blood, urine, toenails, and duplicate-plate food collections for selenium analysis. About half of the 142 free-living subjects had selenium intakes greater than 2.54 mumol/d (200 micrograms/d) (range 0.86-9.20 mumol/d, or 68-724 micrograms/d). Physical findings characteristic of selenium toxicity were not present nor were clinically significant changes in laboratory tests or frequency of symptoms related to selenium in the blood, toenails, or diet. We found no evidence of toxicity from selenium in subjects whose intake was as high as 9.20 mumol/d (724 micrograms/d).  相似文献   
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Three-dimensional CT scan imaging obtained by using helicoidal CT scan provides the basis for an endoscopic exam said to be virtual since no invasive procedure is actually performed. Compared to optical endoscopy this easily accessible exam offers additional information especially for the analysis of the infraglottic and tracheal areas, which are two anatomically rigid segments. This property facilitates their three-dimensional reconstruction. Our study encompassed 6 patients presenting with a stenosis of the laryngotracheal tract. In 5 of them it was possible to correlate optical and virtual endoscopic imaging. Coupling both exams significantly improved the diagnostic investigation and facilitated the management of the disease. However, the real contribution of virtual endoscopy to the exploration of tumoral conditions still remains to be determined given the low degree of tissue resolution. As a consequence parietal and extraparietal lesional spreading is more accurately assessed by axial scan imaging.  相似文献   
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A total of 100 men with a mean age of 63 years underwent, in the following order, prostate specific antigen (PSA) assay (radioimmunometric assay, normal less than 2.5 ng./ml.), rectal examination, transrectal ultrasonography with a 7 MHz. probe, measurement of the prostatic volume, and 6 ultrasound-guided randomized biopsies and biopsies of any hypoechogenic zones. All men with a suspicious prostate on rectal examination (nodule, induration or firm zone) were excluded from the study. There were 14 prostatic cancers detected: 3 (8.5%) in men less than 60 years old, 4 (11%) in men between 60 and 70 years old and 7 (24%) in men more than 70 years old. No cancer was detected in men with a PSA level of less than 10 ng./ml., 5 (26%) were detected in 19 men with a PSA level of 10 to 19 ng./ml., 4 (40%) were detected in 10 men with a PSA of 20 to 29.9 ng./ml. and 5 (100%) were detected in 5 men with a PSA of 30 or more ng./ml. A total of 66 men (66%) had a PSA level of less than 10 ng./ml. There were 18 (18%) hypoechogenic zones detected: 2 (11%) were positive for cancer but, over-all, the hypoechogenic zones revealed cancer in only 2 of 100 cases (2%). In 12 of the 14 cancers detected (86%) with no clinical suspicion the PSA level was higher than the maximal PSA level related to the prostate weight. We conclude that systematic randomized prostatic biopsies are the best method of early diagnosis, detecting 41% of all prostatic cancers in men with a normal rectal examination when the PSA level is 10 ng./ml. or more. The real question is to determine whether this early diagnosis is useful for the patient, since presently, there is no certainty of the therapeutic benefit in terms of quantity and quality of life.  相似文献   
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OBJECTIVE: This study aimed at evaluating the performance of Cine-MRI to assess swallowing in patients previously treated for head and neck cancer. MATERIALS AND METHODS: 10 healthy control subjects and a cohort of 10 patients with 8 partial glossectomies, 1 total laryngectomy and 1 glossolaryngectomy underwent imaging from October 2005 to February 2007. The MRI examinations were performed on a 1.5 Tesla system (Siemens Avanto), with True-Fisp sequences (TR = 170 ms, TE = 1 ms, slice thickness = 10 mm) at a rate of 8 pictures per second, during dry swallowing. RESULTS: Results are relevant for real-time spatial resolution from lips to larynx and dynamic motions analyses of tongue, velum, posterior pharyngeal wall and larynx during dry swallowing. Oro-pharyngo-laryngeal occlusion deficiency induces aspiration in case of partial glossectomy. Total laryngectomy modifies tongue, velum and pharynx landmarks. CONCLUSION: Cine-MRI i) provides functional insight from the oral cavity to the larynx, ii) gives accurate informations about impairments due to the pathology and its treatment, iii) completes others investigations like fiberoptic endoscopy or transit time, iiii) allows a precise analysis of the muscular movements involved in the deficient swallowing mechanism, in order to optimize rehabilitative strategies and results.  相似文献   
48.
CT imaging of the anterior ethmoidal artery: anatomic correlation   总被引:1,自引:0,他引:1  
PURPOSE: To identify the anterior ethmoidal artery (AEA) of a skull specimen on CT prior to transnasal endoscopic surgical management of anterior epistaxis. MATERIALS AND METHODS: From a medial canthotomy approach, the AEA was located and a marker placed on 9 skull specimens (18 AEA). CT with 2D reformations was then performed. The AEA were then dissected using an endoscopic anterior ethmoidectomy approach. The presence of AEA procidence was recorded. RESULTS: Correlation between CT and surgical findings allowed identification of 2 criteria predictive of AEA procidence: 1) presence of an ethmoid bulla above the AEA canal 2) AEA canal located below (not within) the ethmoid roof, anterior to the bulla. CONCLUSION: High resolution CT depiction of the AEA provides information regarding its accessibility for endoscopic ligation in patients with severe anterior epistaxis as an alternative to external ligation while demonstrating the upper limit of the anterior ethmoid.  相似文献   
49.
PURPOSE: To assess the value of CT for diagnosis and follow-up of AFS. Evaluation of characteristic CT features of AFS. METHODS: Retrospective review of 12 cases of AFS presenting with all published diagnostic criteria (1) chronic rhinosinusitis refractory to standard management (2) CT features of chronic sinusitis (3) anatomopathologic, immunoallergologic, biochemical and mycologic criteria. CT findings were correlated with surgical findings and reviewed by one ENT and two radiologists to assess the diagnostic value of different CT features, alone or in association. RESULTS: AFS was isolated in 6 cases, and associated with allergic bronchopulmonary aspergillosis (ABPA) in 6 cases. CT showed pan- or polysinusitis, unilateral or bilateral, with mucosal thickening, sinus opacification frequently heterogeneous, bony changes, fluid trapping, and with pseudotumoral appearance in 3 cases. CONCLUSION: CT findings alone are not specific or pathognomonic but may suggest AFS in the correct clinical or immunoallergologic setting. It may alert the physician to the need for complementary work-up, exclude the presence of associated lung disease, and better adapt treatment and follow-up.  相似文献   
50.
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