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71.
We present a case of unilateral Küttner tumour in the right submandibular gland. Its clinical course and ultrasound features inclined us to include a malignant lesion in the differential diagnosis. US-histopathologic correlation explained the ultrasound appearance of the lesion.  相似文献   
72.
Oxygen-derived free radicals have been implicated in the pathogenesis of various disease states, including myocardial ischemia and reperfusion. In this article, we review 1) the evidence linking free radical production and myocardial injury during myocardial ischemia and reperfusion and 2) results of studies of the effects of the pharmacological therapies available potentially to prevent free radical-mediated injury. Free radicals can be produced during ischemia and reperfusion by several different biochemical pathways. Of these, the xanthine oxidase reaction and the output of free radicals by neutrophils that have accumulated in damaged tissue have been studied extensively. When produced, free radicals can potentially damage myocytes or endothelial cells through peroxidation of membrane lipids or damage to proteins or nucleic acids. Using electron spin resonance spectroscopy, several studies have shown a 'burst' of oxygen free radicals immediately after reperfusion. Moreover, exogenous generation of intravascular free radicals has been shown to produce marked vascular and myocyte damage, as well as contractile dysfunction. 'Anti-free radical' interventions, such as xanthine oxidase inhibitors and free radical scavengers have been reported to prevent contractile dysfunction and reperfusion-induced arrhythmias after an episode of reversible ischemic injury. However, after more severe episodes of ischemia, such interventions have had conflicting effects on myocardial infarct size. 'Anti-free radical' interventions could be of potential use in situations where reversible ischemic injury occurs. In situations where reperfusion is achieved after irreversible ischemic injury has occurred, the potential beneficial effect of these treatments on infarct size is more doubtful.  相似文献   
73.
White  EM; Edelman  RR; Wedeen  VJ; Brady  TJ 《Radiology》1986,161(1):245-249
Intravascular signal from flowing blood is frequently observed on magnetic resonance (MR) images and may be indistinguishable from partial or complete vascular occlusion caused by thrombus or tumor. With a phase-display reconstruction method, qualitative assessment of large-vessel patency within the abdomen was undertaken in 15 healthy subjects and 12 patients with angiographically or surgically documented intravascular thrombus or tumor. Computed tomographic (CT) scans were available in all patients for correlation. MR studies were performed with a multisection spin-echo pulse sequence and two-dimensional Fourier transform spatial encoding. Data acquired from a single sequence was reconstituted in two ways to provide both routine anatomic images and a pictorial representation of large-vessel flow on a phase-sensitive image. With this method, reliable and easy differentiation of intraluminal thrombus and tumor from blood flow signal within large vessels was achieved. Information from these phase-display images compared favorably with findings from angiography and contrast-enhanced CT in the determination of luminal patency and obstruction.  相似文献   
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This review was conducted to determine reliable evidence regarding the safety, feasibility, effectiveness, and cost-effectiveness of cataract extraction performed as a day care versus in-patient procedure. The search to identify randomized controlled trials comparing day care and in-patient surgery for age-related cataract included the Cochrane Eyes and Vision Group Trials Register, the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and LILACS Latin American and Caribbean Literature on Health Sciences. Assessment of methodological quality was based on criteria defined by the Cochrane Collaboration. The primary outcome was the achievement of a satisfactory visual acuity 6 weeks after operation. Two trials, involving a total of 1284 people, are included. One trial reported statistically significant differences in early postoperative complication rates in the day care group, which had no clinical relevance to visual outcomes 4 months postoperatively. Mean change in visual acuity Snellen lines of the operated eye 4 months postoperatively was 4.1 standard deviation SD 2.3 for the day care group and 4.1 SD 2.2 for the in-patient group. Costs were 20% more for the in-patient group attributable to higher costs for overnight stay.  相似文献   
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Carbon monoxide (CO) and CO-releasing molecules (CO-RMs) inhibit platelet aggregation in vitro. Herein, we compare the anti-platelet action of CORM-3, which releases CO rapidly (t (?) 1?min), and CORM-A1, which slowly releases CO (t(?)?=?21?min). The anti-platelet effects of NO donors with various kinetics of NO release were studied for comparison. The effects of CO-RMs and NO donors were analyzed in washed human platelets (WP), platelets rich plasma (PRP), or whole blood (WB) using aggregometry technique. CORM-3 and CORM-A1 inhibited platelet aggregation in human PRP, WP, or WB, in a concentration-dependent manner. In all three preparations, CORM-A1 was more potent than CORM-3. Inhibition of platelets aggregation by CORM-A1 was not significantly affected by a guanylate cyclase inhibitor (ODQ) and a phosphodiesterase-5 inhibitor, sildenafil. In contrast, inhibition of platelet aggregation by NO donors was more potent with a fast NO releaser (DEA-NO, t (?)?=?2?min) than slow NO releasers such as PAPA-NO (t (?)?=?15?min) or other slow NO donors. Predictably, the anti-platelet effect of DEA-NO and other NO donors was reversed by ODQ while potentiated by sildenafil. In contrast to NO donors which inhibit platelets proportionally to the kinetics of NO released via activation of soluble guanylate cyclase (sGC), the slow CO-releaser CORM-A1 is a superior anti-platelet agent as compared to CORM-3 which releases CO instantly. The anti-platelet action of CO-RMs does not involve sGC activation. Importantly, CORM-A1 or its derivatives representing the class of slow CO releasers display promising pharmacological profile as anti-platelet agents.  相似文献   
80.
Appraisal of the methodological quality of systematic reviews would reflect on their utility for the clinicians and policymakers. This study was done to assess the quality of systematic reviews published in five leading Indian medical journals using AMSTAR. 22 systematic reviews of healthcare interventions were identified. The scores ranged 0 to 10 (mean 3.77 and median 2.5), 9 reviews scored > 4/11. Most frequent ‘yes’ and ‘no’ scores were: publication status as an inclusion criterion (12 / 22), respectively and duplicate study selection and data extraction (17 /22). Several suboptimal aspects of methodological quality were identified in the reviews evaluated.  相似文献   
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