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71.
Smith  TP; Cragg  AH; Berbaum  KS 《Radiology》1989,170(3):941
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72.
Background  Alopecia areata is a complex genetic disease with still many unknown aspects, and many studies have been tried to find some clues about it.
Objective  We aimed to investigate the demographic and clinical characteristics of alopecia areata in Turkish patients.
Methods  Demographic data, localization, attack number in addition to some parameters such as disease duration, severity, age of onset, family history and ophiasis pattern were evaluated in 539 alopecia areata patients.
Results  The male to female ratio was 1.6 : 1. Occipital and beard-moustache areas were mostly affected. Positive family history was noticed in 24.1% of the patients. The age of onset was earlier in women than in men ( P =  0.04). Severe forms showed more persistent (≥ 1 year) disease duration ( P =  0.00). Ophiasis was more common in severe, long duration (≥ 1 year) and early onset (≤ 18 years) disease ( P =  0.00 for all parameters). Childhood alopecia areata (≤ 18 years) was also associated with long duration of the disease ( P =  0.016) and positive family history ( P =  0.008) when compared with adult onset (> 18 years) alopecia areata.  相似文献   
73.
A variety of endoscopic methods are available as the main tools in the diagnostics and therapy of various complications after visceral and thoracic surgery. Indications for endoscopic interventions are anastomotic leaks, stenoses, GI-tract bleedings, biliary lesions and functional problems after surgical procedures. The most common are fibrin sealing of fistulas, dilatation and bougienage, injection therapy for bleeding, bile duct interventions and stent implantations. In most cases operative revisions can be avoided by using endoscopic methods with an overall good success rate. No disadvantages are foreseen following conventional operative interventions if the endoscopic treatment is not successful.  相似文献   
74.
Vascular endoprostheses made of knitted tantalum wire and expanded over angioplasty balloons were placed into aortas or iliac arteries of 14 normal dogs. Twelve stents were placed into the infrarenal abdominal aorta and two stents in the left common iliac arteries by the left carotid artery approach. To firmly expand the stent against the vascular wall, nominal stent sizes 0.5-1.0 mm larger than the measured arterial diameter were required. Arteriography performed at specified follow-up intervals showed no evidence of thrombi or emboli; all side branches (lumbar arteries) covered by the stents remained patent. Vascular diameter decreased minimally at 8 and 26 weeks, associated with histopathologic evidence of neointimal buildup. This buildup was highest at 8 weeks (mean, 313 microns) and was slightly less at 26 weeks (mean, 223 microns). Almost complete coverage by endothelium was seen as early as 3 weeks. It is concluded that the flexible tantalum wire stents are well tolerated by the arterial wall and become quickly endothelialized. No excessive neointimal buildup was observed during the 6-month study.  相似文献   
75.
76.
To determine the factors that influenced doctors' prioritization and decisions on safe waiting time for coronary artery bypass surgery, 50 'paper patients', based on a random sample of cases who actually had surgery, were assessed by 33 clinicians. We used linear regression models to reflect the impact of clinical and non-clinical 'cues' on safe waiting time and priority decisions. The benefits of surgery tended to be over-estimated. For example, the average perceived gain in life expectancy for patients with left main-stem disease was 6.74 years. However, models incorporating only the perceptions of benefit as independent variables (i.e. the anticipated symptom reduction, MI risk reduction and life expectancy extension), had only modest explanatory power (mean R2 was 0.55 for safe waiting time, and 0.56 for priority decisions). Models which incorporated perceptions of benefit and the cases' clinical and non-clinical characteristics had generally much higher explanatory power (mean R2, 0.83 and 0.86, respectively). Lifestyle and demographic variables had much less impact on the doctors' judgements than the major clinical cues of angina severity and left main-stem stenosis. Demographic and lifestyle cues had different impacts on safe waiting time and priority for about 25% of doctors.   相似文献   
77.
The recent finding that ribavirin has a mutagenic capacity in a poliovirus replicon model pushing the virus into error catastrophe, provides a possible explanation for the remarkable synergistic effect of ribavirin when combined with interferon in the treatment of chronic hepatitis C virus (HCV)-infected patients. However, ribavirin-induced hypermutation resulting in loss of vital genetic information and viral clearance, does not occur during treatment of HCV-infected patients, as can be inferred from the lack of viral inhibition when treating HCV-infected patients with ribavirin alone. We therefore hypothesized that ribavirin induces mutations in the C-terminal part of the viral NS5A gene, a region found to be correlated with interferon sensitivity. Ribavirin-induced mutations resulting in the appearance of viral variants more sensitive to interferon would explain the synergistic effect of ribavirin when combined with interferon. To test this hypothesis we retrospectively analysed sequences of the C-terminal half of the NS5A gene before and during treatment in six HCV genotype 1-infected patients who had been treated with combination therapy after initial failure to respond permanently to interferon alone. Our results show that during the early treatment phase mutation rate is not enhanced during combination therapy and that, at least in the major variant, shifts in the NS5A domain resulting in the occurrence of viral variants, which are more interferon-sensitive, do not occur.  相似文献   
78.
Although fractures of the clavicle are common, complications are rare. A 41 year old painter developed two uncommon complications of clavicular fracture, mechanical intermittent subclavian artery occlusion and subclavian vein thrombosis. Both conditions were clearly identified on the clinical symptoms and signs and confirmed with dynamic angiography and computerised tomography. Operative intervention led to complete resolution of symptoms.  相似文献   
79.
目的:对坐式排球运动员进行腰背肌筋膜炎损伤检查与积极治疗,并制定有效措施预防腰背肌筋膜炎损伤的发生,以提高其成绩水平。方法:实验于2006-03/07于鲁东大学体育学院完成。①选取2006年参加山东省残疾人运动会的烟台队坐式排球运动员22名,男12名,女10名,平均年龄(27±2)岁。②对22名坐式排球运动员进行腰背肌筋膜炎损伤状况检查,病历需要详细注明受伤原因、腰背部肌肉筋膜的痛点及运动障碍、确定损伤性质是急性还是慢性、确定损伤位置、抗阻力实验是否为阳性。③检查完毕后,对存在腰背肌筋膜炎损伤的运动员采用日本温热式低周波治疗器 外敷中药治疗。温热式低周波治疗器主要选择拍打、推压、按摩、左右变换按揉,每次治疗时间为15min,温度控制在38~43℃,将(-)导子放在痛点部位,( )导子放在阿是穴、肾俞、命门、腰眼等相应的治疗穴位上。中药以散寒活血祛瘀止痛为主,将川乌头、天南星、生半夏、乳香、没药、独活、马钱子、红花等混合研成粉状,加入体积分数为0.75的乙醇搅拌成糊状,用沙布制成直径约15cm饼状态物,敷于患处,6~12d为1个疗程。④治疗结束后,对所有队员1年的训练过程制定预防腰背肌筋膜炎的有效措施,即训练中加强腰背部肌肉力量和伸展性;通过温热式低周波治疗器 推拿按摩促进腰背部肌肉筋膜的放松及疲劳恢复;训练中采用肌肉牵伸性练习,注意避免牵拉过度;建立急性运动损伤档案,尽量减少急性损伤转变为慢性损伤的可能性。结果:①腰背肌筋膜炎的患病率:烟台队22名坐式排球运动员中,10名存在腰背肌筋膜炎损伤,患病率45.5%,损伤部位集中在腰背部和颈部。②腰背肌筋膜炎损伤治疗结果:采用日本温热式低周波治疗器 外敷中药治疗一两个疗程后效果良好,10名腰背肌筋膜炎损伤运动员中9名痊愈,治愈率90%。③采取预防措施后运动员腰背肌筋膜炎的发生情况:训练中采取预防措施,1年后22名坐式排球运动员腰背肌筋膜炎损伤得到明显控制,腰背肌筋膜炎患病率为29.3%,与治疗预防前比较下降16.2%,效果显著。结论:坐式排球运动损伤部位集中在腰背部和颈部,腰背肌筋膜炎是常发病。针对发病原因及时治疗并给予有效预防措施,可明显降低腰背肌筋膜炎损伤发生率,对其运动训练能力和比赛成绩的提高均具有积极意义。  相似文献   
80.
The mouse mdr1a (also called mdr3) P-GP is abundant in the blood-brain barrier, and its absence in mdr1a (-/-) mice leads to highly increased levels of the drugs ivermectin, vinblastine, digoxin, and cyclosporin A in the brain. We show here that the drugs loperamide, domperidone, and ondansetron are transported substrates for the mouse mdr1a P-GP and its human homologue MDR1. Phenytoin is a relatively weaker substrate for each, and the drugs haloperidol, clozapine, and flunitrazepam are transported hardly or not at all. Tissue distribution studies demonstrated that the relative brain penetration of radiolabeled ondansetron and loperamide (and their metabolites) is increased four- and sevenfold, respectively, in mdr1a (-/-) mice. A pilot toxicity study with oral loperamide showed that this peripherally acting antidiarrheal agent gains potent opiatelike activity in the central nervous system of mdr1a (-/-) mice. mdr1a (-/-) mice also showed increased sensitivity to neurolepticlike side effects of oral domperidone. These results point to the possible role that the drug-transporting P-GP(s) may play in the clinical use of many drugs, especially those with potential targets in the central nervous system.  相似文献   
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