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排序方式: 共有467条查询结果,搜索用时 15 毫秒
41.
MB Elam J Heckman JR Crouse DB Hunninghake JA Herd M Davidson IL Gordon EB Bortey WP Forbes 《Canadian Metallurgical Quarterly》1998,18(12):1942-1947
Cilostazol is an antiplatelet agent and vasodilator marketed in Japan for treatment of ischemic symptoms of peripheral vascular disease. It is currently being evaluated in the United States for treatment of symptomatic intermittent claudication (IC). Cilostazol has been shown to improve walking distance in patients with IC. In addition to its reported vasodilator and antiplatelet effects, cilostazol has been proposed to have beneficial effects on plasma lipoproteins. We examined the effect of cilostazol versus placebo on plasma lipoproteins in 189 patients with IC. After 12 weeks of therapy with 100 mg cilostazol BID, plasma triglycerides decreased 15% (P<0.001). Cilostazol also increased plasma high density lipoprotein cholesterol (HDL-C) (10%) and apolipoprotein (apo) A1 (5.7%) significantly (P<0.001 and P<0.01, respectively). Both HDL3 and HDL2 subfractions were increased by cilostazol; however, the greatest percentage increase was observed in HDL2. Individuals with baseline hypertriglyceridemia (>140 mg/dL) experienced the greatest changes in both HDL-C and triglycerides with cilostazol treatment. In that subset of patients, HDL-C was increased 12.2% and triglycerides were decreased 23%. With cilostazol, there was a trend (3%) toward decreased apoB as well as increased apoA1, resulting in a significant (9.8%, P<0.002) increase in the apoA1 to apoB ratio. Low density lipoprotein cholesterol and lipoprotein(a) concentrations were unaffected. Cilostazol treatment resulted in a 35% increase in treadmill walking time (P=0.0015) and a 9.03% increase in ankle-brachial index (P<0.001). These results indicate that in addition to improving the symptoms of IC, cilostazol also favorably modifies plasma lipoproteins in patients with peripheral arterial disease. The mechanism of this effect is currently unknown. 相似文献
42.
DA Spain TM Bergamini JF Hoffmann EH Carrillo JD Richardson 《Canadian Metallurgical Quarterly》1998,64(6):522-5; discussion 525-6
Multiple-trauma patients are at increased risk for deep venous thrombosis (DVT) but are also at increased risk of bleeding, and the use of heparin may be contraindicated. Sequential pneumatic compression devices (SCDs) are an alternative for DVT prophylaxis. However, lower extremity fracture or soft tissue injury may preclude their use. In these circumstances, foot pumps (FPs) are often substituted, yet little clinical data exist to support their use. We identified 184 consecutive high-risk trauma patients who received DVT prophylaxis with compression devices. We reviewed demographic data, mechanism of injury, Injury Severity Score, injury pattern, and method of prophylaxis. Generally, SCDs were preferred, but FPs were substituted in patients with lower extremity injuries. Occurrences of DVT or pulmonary embolism were also noted. Patients surviving less than 48 hours were excluded. SCDs were used in 118 patients (64%) and FPs in 66 patients (34%). There were no differences in age, Injury Severity Score, or presence of shock on admission. As expected, FP patients were more likely to have lower extremity fractures (65 vs 26%; P < 0.05) and were also more likely to have associated pelvic fracture (59 vs 25%; P < 0.05) and chest injury (61 vs 26%, P < 0.05). There was no difference in the incidence of head injury, although SCD patients had more severe head injuries (Glasgow Coma Score, 7.9 vs 10.5; P < 0.05). The overall incidence of DVT was 5.4 per cent (10 of 184), with no differences between the two groups (SCD 7% vs FP 3%). Three patients had a pulmonary embolism (FP, two; SCD, one), none of which were fatal. Compression devices provide adequate DVT prophylaxis with a low failure rate (3-8%) and no device-related complications. FPs appear to be a reasonable alternative in the high-risk trauma patient when lower extremity fractures precludes use of SCD. 相似文献
43.
In experiments on anesthetized cats the ability of natural enkephalins to affect baseline heart rate, the magnitude of vagal chronotropic effect and its components, inhibitory tonic and synchronizing, was compared with activity of synthetic analogs and short fragments of enkephalins. Substitutions of met-enkephalin structure in second and fifth positions did not modify its cardiac activity. When Tyr1 was removed the peptide lost ability to affect baseline heart rate and the magnitude of synchronizing vagal component, but modulatory influence on inhibitory tonic vagal effect still persisted. The conclusion has been made that various parts of amino acid chain of met-enkephalin have different significance in realization of cardiac effects evoked by this peptide. 相似文献
44.
BACKGROUND: Increasing referral numbers make the development of simplified accurate methods of diagnosing the sleep apnoea/hypopnoea syndrome highly desirable. The accuracy of one such system--the ResCare Autoset--has been examined. METHODS: Thirty one consecutive patients assessed by polysomnography had simultaneous monitoring of their respiratory pattern using the Autoset system. The Autoset detects episodes of flattening of the flow/time profile using nasal cannulae. RESULTS: There was a good correlation (r = 0.85) between the number of apnoeas+hypopnoeas/hour in bed recorded using polysomnography and the Autoset system. The median difference in such events was 3.1 (95% confidence interval 8.4 to -1.6)/hour in bed. In two patients the Autoset scored 70 apnoeas+hypopnoeas/hour in bed compared with 34 apnoeas+hypopnoeas with 35 arousals/hour in bed by polysomnography; however, this did not alter the diagnostic category of either patient. Autoset gave a sensitivity of 100%, specificity of 92%, positive predictive value of 92%, and negative predictive value of 100%, which was better than oximetry alone. A sleep study using the Autoset system costs 14 pounds compared with 126 pounds for polysomnography. CONCLUSIONS: The Autoset is clinically useful for diagnosing the sleep apnoea/hypopnoea syndrome. 相似文献
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Nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase activity was examined in the cranial sensory ganglia and brainstem of the banded dogfish, Triakis scyllia. Positive neurons were found in the vagal sensory ganglion projecting to the coelomic organs, but not in those projecting to the gills or the lateral line organs. Nerve terminals in the vagal lobe were also positive. No positive neurons were found in the glossopharyngeal, facial, or trigeminal sensory ganglia. These results suggest that use of nitric oxide in the vagal sensory transmission from the coelomic organs may have been maintained in the evolutionary process from fish to mammals. 相似文献
50.
With a growing emphasis on human identification, iris recognition has recently received increasing attention. Iris recognition includes eye imaging, iris segmentation, verification, and so on. In this letter, we propose a novel and efficient iris recognition method which employs a cumulative‐sum‐based grey change analysis. Experimental results demonstrate that the proposed method can be used for human identification in efficient manner. 相似文献