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41.
张黎川 《现代医药卫生》2005,21(10):1191-1192
目的:探讨黄杆菌属致下呼吸道感染的临床特点及对常用抗生素的耐药情况。方法:分析我院六年来机械通气致下呼吸道黄杆菌感染的11例临床资料,平板稀释法测定常用抗菌药物对该菌株的最低抑菌浓度,采用法国生物梅里埃公司API系统进行细菌学鉴定,以美国国家实验室标准化委员会NCCLS的标准判定结果。结果:全部应用广谱抗生素,年龄>60岁者8例,机械通气到发生黄杆菌感染的平均时间为18天,死亡4例;耐药率高,仅对头孢哌酮/舒巴坦、复方磺胺甲恶唑、哌拉西林、左氧氟沙星等较敏感。结论:机械通气致下呼吸道黄杆菌感染常发生在基础状态较差,机械通气时间较长,且长期应用广谱抗生素的老年患者,临床表现常无特征性,细菌耐药严重,病死率高  相似文献   
42.
Technetium-99m sestamibi was used for functional investigation of the muscle perfusion of lower extremities in 35 patients with peripheral vascular disease. The aim was to test what useful information could be obtained by additional imaging of the legs in patients referred for risk stratification with dipyridamole myocardial scanning. Posterior images were acquired over the thighs and calves after postocclusive reactive hyperaemia and at rest. Inter- and intraextremity ratios and differences between the stress and rest data were used for the assessment of abnormal circulation. Arteriography was performed in every case, and surgical procedures or transluminal angioplasty in 31 patients. To estimate diagnostic accuracy, the results of99mTc-sestamibi scintigraphy were compared with those of angiography and the functional consequences of revascularization procedures. The sensitivity and specificity of99mTc-sestamibi scintigraphy were 55% and 25%, respectively, with an overall accuracy of 50%. Apparently methodological error was not responsible for these poor results. Instead, a paradoxically high uptake of the radiopharmaceutical in muscles supplied by significantly stenosed vessels was identified as the main source of both false-negative and false-positive results. This phenomenon resembles the findings of a previous study involving delayed administration of thallium-201 after exercise. In conclusion,99mTc-sestamibi scintigraphy has not proved sufficiently reliable to help in the management strategy for patients with peripheral vascular disease.  相似文献   
43.
The maximal urinary osmolality that can be reached by the kidney is reduced with age. This may be due to impaired NaCl transport by the medullary thick ascending limb of Henle's loop, which is part of the renal concentrating mechanism and is modulated by antidiuretic hormone (ADH). We therefore tested in vitro a possible age-related change in the transport capacity and in the response of this nephron segment to ADH in young (1–2 months) and old (20–24 months) mice. The transepithelial potential difference (V te) was significantly higher in young mice (+8.5±0.4 mV, n=13) than in old ones (+6.6±0.5 mV, n=17). Addition of 0.1 nmol.l–1 ADH to the bath solution significantly increased V te by 5.2±0.5 mV in the young and by 3.1±0.6 mV in the old animals. Application of dibutyryl-cAMP (0.1 mmol.1–1) did not further increase the hormonal response in both groups. The ADH-mediated increase in the corresponding equivalent short-circuit current (I SC = V te/Rte) was twice as great in young mice as in old, indicating that the stimulation of NaCl transport by ADH across the medullary thick ascending limb is significantly reduced with age. These results suggest that the previously reported age-related defect in the urinary concentrating ability of the kidney is partly due to a decreased response of the medullary thick ascending limb to ADH.  相似文献   
44.
Restless legs syndrome (RLS) is one of the commonest movement disorders affecting sleep and also daytime functioning. The prevalence may be 8%–10% of the white Caucasian population. The diagnosis is simple and is based on a well-validated clinical questionnaire, yet misdiagnosis is common and the condition remains underdiagnosed and consequently inappropriately treated, often causing great distress to the sufferers. In spite of robust evidence for effective treatment of RLS, patients may often be told to “put up with the symptoms” and suffer the consequence of years of poor sleep which may lead to major lifestyle changes. This review addresses the diagnostic issues, the differential diagnosis, and the evidence base for treatment of the common condition.  相似文献   
45.
髓内固定系统治疗下肢骨折临床应用   总被引:1,自引:0,他引:1  
目的:探索髓内固定系统在下肢骨折治疗中的操作原理。方法:认真术前掌握髓内钉系统的设计和操作,结合对骨折部位、类型及生物力学分析等选择内固定,通过对下肢骨折157例的术中观察及术后摄片对照等探索髓内钉系统的操作情况。结果:术后摄片骨折达解剖或功能复位,随诊3~24月,优良率为94.88%。结论:下肢骨折治疗中,髓内钉系统是一种优良的支撑、复位、固定器材:术前认真分析骨折类型及力学特点,有助于术中顺利操作和骨折的坚强固定。  相似文献   
46.
Summary Over a four year period, thirteen patients over the age of 60 (mean 69 years) underwent reconstruction of lower extremity defects with free tissue transfers. Ten latissimus dorsi, one tensor facia lata, and two rectus abdominus free flaps were used. Despite significant risk factors which included previous tobacco use, hypertension, diabetes mellitus, and angiographic vessel abnormalities, ten of thirteen cases had successful outcomes. There was one acute flap failure secondary to arterial thrombosis. Four flaps had delayed healing, with one patient eventually requiring amputation secondary to persistent pain and wound drainage. This experience demonstrates that free flap reconstruction of lower extremity defects in the elderly patient is a reasonable alternative to amputation when other options are limited.From the Section of Plastic and Reconstructive Surgery at the Mayo Clinic and Mayo Foundation, Rochester, Minnesota, USA Requests for reprints: J. Fisher, M.D.  相似文献   
47.
下肢静脉病变顺、逆行造影的诊断价值   总被引:5,自引:0,他引:5  
目的:探讨下肢静脉病变顺、逆行造影X线表现与病理改变的关系。方法:回顾性分析86例(119侧)下肢静脉病变顺、逆行造影X线表现。结果:顺行造影显示原发性下肢深静脉瓣膜关闭不全84侧,交通静脉瓣膜关闭不全14侧,单纯性瓣膜关闭不全11侧,静脉瘤或弥漫性血管湖6侧,先天性下肢静脉发育异常4侧。逆行造影显示0级13侧,Ⅰ级58侧,Ⅱ级21侧,Ⅲ级19侧,Ⅳ级8侧。结论:下肢静脉病变顺、逆行同时造影能更好地显示下肢浅、深静脉瓣膜功能,为临床诊断或治疗提供非常有价值的依据。  相似文献   
48.
目的 探讨肢体缺血预处理对兔肺缺血再灌注损伤的影响.方法 健康日本大耳白兔18只,体重2.0~2.5 kg,雌雄不拘,随机分为3组(n=6):假手术组(S组)开胸后左侧肺门穿线但不结扎,旷置观察340 min;缺血再灌注组(IR组)开胸旷置100 min,阻断左侧肺门,左肺不张后60 min再灌注180 min;肢体缺血预处理组(L组)捆绑双后肢10 min,松开10 min,反复3次后恢复灌注,60 min后阻断左侧肺门60 min,再灌注180 min.于缺血前、再灌注15、30、60、120、180 min时采集左颈内动脉血样行血气分析,计算呼吸指数(R1);于再灌注180 min时处死动物,取左肺上叶组织,测定超氧化物歧化酶(SOD)、髓过氧化物酶(MPO)活性及丙二醛(MDA)含量,计算肺湿干重比(W/D);取左肺下叶行支气管肺泡灌洗,计算肺通透性指数;取左肺中叶组织,观察肺组织病理学,进行弥漫性肺泡损伤(DAD)评分.结果 与s组比较,IR组RI、MDA含量、MPO活性、肺W/D、肺通透性指数和DAD评分升高,SOD活性降低(P<0.05或0.01);与IR组比较,L组RI,MDA含量、MPO活性、肺W/D、肺通透性指数和DAD评分降低,SOD活性升高(P<0.05或0.01);L组和S组间上述指标比较差异无统计学意义(P>0.05).L组和S组肺组织病理损伤程度较IR组减轻.结论 肢体缺血预处理可减轻兔肺缺血再灌注损伤.  相似文献   
49.
ABSTRACT Embryotoxicity and teratogenicity of cadmium (Cd) and modulation of its effects by N-acetyl-L-cysteine (NAC) were evaluated in mice. Pregnant ICR mice were intraperitoneally injected with 3.5 mg/kg of CdCl2 on day 10 or 11 of gestation (vaginal plug = day 0). Pregnant mice were pretreated with 160 mg/kg of NAC intravenously 2 hours before dosing with CdCl2. Pregnant mice were killed on day 17 of gestation. Fetuses were examined for external malformations, especially limb malformations, cleft palate and abnormal palatal rugae. There was little difference in body weight gain of dams during the gestation period in the groups treated with NAC plus Cd as compared with the groups treated with Cd alone. Pretreatment with 160 mg/kg of NAC decreased the fetal mortality, incidence of cleft palate and abnormal palatal rugae induced by Cd on day 11. On day 10, pretreatment with NAC decreased the incidence of Cd induced abnormal palatal rugae. These results clearly indicate that NAC exerts protective effects against embryotoxicity and teratogenicity of Cd.  相似文献   
50.
[目的]探讨伴有上肢局部水肿的颈椎病患者的发病机理和与手术颈椎减压的关系。[方法]总结分析4a来收治的10例伴有上肢局部水肿的颈椎病人,其中脊髓型颈椎病7例,神经根型颈椎病2例,后纵韧带骨化型1例,7例行前路椎体次全切减压植骨内固定,1例行前路椎体次全切+单间隙间盘摘除植骨内固定,2例行后路减压植骨内固定,术后观察患者水肿消退情况。[结果]10例病人上肢局部水肿不同程度消退,前路手术者较后路手术者消退快。[结论]颈椎病患者上肢水肿的发生与颈交感神经受激惹有关,通过前路或后路颈椎管减压,去除颈椎不稳、椎间盘突出、骨赘等交感神经受激惹因素,水肿可逐步消退。  相似文献   
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