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Daniels DL; Czervionke LF; Millen SJ; Haberkamp TJ; Meyer GA; Hendrix LE; Mark LP; Williams AL; Haughton VM 《Radiology》1989,171(3):807-809
The authors evaluated magnetic resonance (MR) images obtained with intravenously administered gadolinium in ten patients who had facial paralysis and no facial nerve tumor. In patients with either Bell palsy (four patients) or facial paralysis after temporal bone surgery (six patients), intratemporal facial nerve enhancement was seen. Facial nerve enhancement on MR images proved to be a nonspecific finding. 相似文献
66.
OBJECTIVE: To analyse changes in the incidence of injuries requiring hospitalisation for child passengers in motor vehicle crashes. DESIGN, SETTING AND PARTICIPANTS: Population-based study of children (aged 0 -15 years) residing in New South Wales and admitted to hospital for injuries resulting from a traffic crash in the period 1 July 1998 - 30 June 2005, identified from the NSW Inpatient Statistics Collection. MAIN OUTCOME MEASURES: Age-standardised rates of hospitalisation for injuries, and trends by inpatient demographics, severity of injuries, and injury sites and types. RESULTS: 2297 children were hospitalised for injuries sustained in a motor vehicle crash over the study period. The overall hospitalisation rate for injuries was relatively constant, with a non-significant decline of - 0.4% (95% CI, - 3.1% to 2.3%). The rate of hospitalisation for serious injuries also declined non-significantly (- 5.5% [95% CI, -11.8% to 1.1%]). Only hospitalisation rates for traumatic brain injuries declined significantly (-11.1% [95% CI, -19.0% to - 2.8%]) over the study period. CONCLUSION: The rate of hospitalisation for injuries to NSW-resident child motor vehicle passengers due to traffic crashes has not significantly decreased. High hospitalisation rates and the subsequent burden to the community and public health system make further injury prevention efforts for child motor vehicle passengers a priority. 相似文献
67.
E F Wijdicks D Hasan K W Lindsay P J Brouwers R Hatfield G D Murray J van Gijn M Vermeulen 《Stroke; a journal of cerebral circulation》1989,20(12):1674-1679
Antifibrinolytic treatment for 4 weeks after a subarachnoid hemorrhage has been shown to have no effect on outcome since a reduction in the rate of rebleeding was offset by an increase in ischemic events. To determine if a shorter course (4 days) of antifibrinolytic treatment before the expected onset of ischemic complications might reduce the rate of rebleeding yet avoid ischemic complications, we prospectively studied a series of 119 patients with subarachnoid hemorrhage; 479 patients with subarachnoid hemorrhage from our previous randomized double-blind study (238 treated with placebo, 241 with long-term tranexamic acid) served as historical control groups. At 3 months' follow-up, the outcome of patients treated with short-term tranexamic acid was not different from that of patients treated with long-term tranexamic acid. The rate of rebleeding (24 of 119, 20%) was near that with placebo (56 of 238, 24%). In contrast, the rate of cerebral infarction (33 of 119, 28%) was almost identical to that after long-term tranexamic acid (59 of 241, 24%), although mortality from cerebral infarction was reduced. Compared with historical control groups, treatment with tranexamic acid for 4 days fails to reduce the incidence of rebleeding but still increases the rate of cerebral infarction. 相似文献
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石杉碱甲类似物的研究Ⅲ.N-甲基吡啶酮石杉碱甲类似物的合成 总被引:1,自引:0,他引:1
石杉碱甲(1)是从中草药石杉属植物千层塔(LycopodiumserratumThunb.)中分得的一种高效可逆的乙酰胆碱酯酶抑制剂,临床试验证实它对早老性痴呆症有显著疗效。本文报道N-甲基吡啶酮石杉碱甲类似物2和3的合成。2-甲氧基-5-甲氧羰基-11-亚甲基-5,9-甲撑环辛-7-烯并吡啶(9)在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮10,再用甲醇钠和碘甲烷甲基化得N-甲基吡啶酮11,11经碱性水解,Curtius重排和氨基的脱保护得N-甲基吡啶酮石杉碱甲类似物2。通过类似的途径从中间体2-甲氧基-5-甲氧羰基-7-甲基-11-酮-5,9-甲撑环辛-7-烯并吡啶(14)合成了类似物3。类似物2和3的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。 相似文献
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Thomas Kerr Brandon DL Marshall Cari Miller Kate Shannon Ruth Zhang Julio SG Montaner Evan Wood 《BMC public health》2009,9(1):171-7
Background
Street-involved youth contend with an array of health and social challenges, including elevated rates of blood-borne infections and mortality. In addition, there has been growing concern regarding high-risk drug use among street-involved youth, in particular injection drug use. We undertook this study to examine the prevalence of injection drug use and associated risks among street-involved youth in Vancouver, Canada. 相似文献70.