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991.
We describe a unique gait phenomenon of bent knees in 9 patients with idiopathic Parkinson disease (mean age, 73.1 +/- 11.1 years), 3 of whom also manifested tiptoeing. The bent-knee posture appeared only during ambulation; in the recumbent position, full or nearly full extension was possible in all patients. The abnormality emerged after long-standing disease (6-23 years from onset) and failed to respond to dopaminergic treatment. Most of the patients also had bent spine (camptocormia). The pathogenesis of these phenomena are unknown, but they might represent a rare type of dystonia.  相似文献   
992.
眼球孤立性脉络膜血管瘤的HR-MRI表现   总被引:4,自引:0,他引:4  
目的 探讨眼球孤立性脉络膜血管瘤的高分辨率磁共振 (HR MRI)影像学特征 ,进一步提高诊断水平。资料与方法 回顾性分析诊断明确的孤立性脉络膜血管瘤 16例共计 17个病灶的位置、数目、形态、大小、MRI信号、强化情况、有无合并视网膜脱离及有无视神经和眼外侵犯等。所有病例均行HR MRI及增强扫描 ,部分病例行脂肪抑制。结果  17个病灶中的 16个呈扁丘状位于眼球内壁的后极。 15个病灶厚度 <5mm ,平均厚度为2 .9mm。病灶边缘清晰 ,T1WI上呈轻度高信号者 16个 ,T2 WI上呈等信号者 15个 ,增强扫描显著强化者有 12个。 3例合并视网膜脱离 ,在T2 WI上多呈等信号 ,T1WI上呈轻度高信号者 ,均无强化。无视神经及眼外侵犯病例。结论  94 %孤立性脉络膜血管瘤的HR MRI表现具有特征性 ,表现为位于眼球内壁后极的较小、基底较宽、边缘清晰的扁丘状病灶。其T1WI信号高于玻璃体 ,T2 WI信号等于玻璃体 ,增强扫描瘤体显著强化。明确其HR MRI影像学特征有助于临床与恶性葡萄膜黑色素瘤相鉴别 ,避免不必要的眼球摘除  相似文献   
993.
目的 探讨长期应用糖皮质激素 (GC)治疗对肾小球疾病患者骨代谢影响的因素。方法  2 0 7例肾小球疾病患者 ,应用常规剂量GC治疗 ,于治疗前及治疗后每隔 3~ 6个月 ,进行了 35 7例次腰椎和股骨近端骨密度 (BMD)、血钙、血磷和骨钙素浓度测定。结果 ①用GC后骨钙素浓度明显降低 (P均 <0 0 0 5 ) ,但其不能预测BMD下降。②用药 15个月后男性各部位BMD均减少 (32 2~111 5 )mg/cm2 ,以L1 4和股骨粗隆更明显 (P均 <0 0 5 ) ,骨丢失率 3 3%~ 10 3% ;女性L1 4BMD均减少(4 3 8~ 76 0 )mg/cm2 ,以L1更明显 (P <0 0 5 ) ,骨丢失率 3 9%~ 7 9%。③年龄与各部位BMD变化呈负相关 ,但不影响GC造成的骨丢失。男性各部位、女性L1 4BMD减少与GC累计剂量和GC用药时间负相关。④用GC15个月 (GC累计剂量 10g以上 ) ,男性L1 4BMD正常的比例从 3/ 4至 3/ 5 ;女性L1和L2 BMD正常者从 3/ 4减少到 1/ 2。结论 长期口服糖皮激素导致与剂量和用药时间相关的腰椎和男性股骨粗隆骨丢失 ,年龄偏大和男性患者骨丢失更明显。  相似文献   
994.
动脉硬化性脑白质病的CT表现与临床分析   总被引:1,自引:0,他引:1  
目的 :探讨动脉硬化性脑白质病的临床与CT表现特点。方法 :收集 10 0例动脉硬化性脑白质病的临床与CT资料进行综合分析。结果 :10 0例的CT表现为 :弥漫性脑白质低密度改变 ,主要分布在双侧脑室旁及半卵圆中心白质区 ,病灶多呈条带状及月晕状。合并脑萎缩 90例 ;脑梗塞 76例 ,其中 2 5例有大的梗塞灶 ,其余为腔隙性梗塞 ;脑出血 9例 ,其中位于壳核 5例 ,丘脑 3例 ,小脑 1例 ;有 15例伴发基底节区软化灶。增强扫描 8例 ,显示病灶无明显增强。结论 :动脉硬化性脑白质病是发生于老年人的缺血性脑血管病 ,高血压动脉硬化是其主要发病因素。  相似文献   
995.
目的 :观察高血压患者在监护拔牙过程中血压、心率、心电图变化及手术应激反应的年龄差异 ,探讨安全科学的监护方法。方法 :对 739例高血压患者监护拔牙的临床资料进行回顾性分析。观察高血压患者和不同年龄组高血压患者麻醉前、中、后 ,拔牙中、拔牙后 ,血压、心率变化。结果 :高血压组血压、心率比对照组显著增高、加快 (P <0 .0 1) ;80岁以上年龄组收缩压显著升高 (P <0 .0 1) ,4 9岁以下年龄组收缩压显著降低 (P <0 .0 5 ,P <0 .0 1)。结论 :各种高血压患者特别是高龄高血压患者 ,在分时安全管理下可以接受无痛拔牙。  相似文献   
996.
BACKGROUND AND OBJECTIVES: We have previously reported that high rat urinary allergen (RUA) exposure was not associated with increased risk of rat allergy in long-term-exposed laboratory animal (LA) workers. We aimed to assess whether strong allergen-specific IgG4 responses could explain the absence of a dose response in these subjects. We investigated whether IgG4 was associated with allergen exposure and prevalence of sensitization or respiratory symptoms to rats. The longitudinal relation between IgG4 and rat allergy was studied using data obtained during 2 years of follow-up. METHODS: Five hundred and twenty-nine LA workers answered a questionnaire on respiratory symptoms and occupational history and participated in skin prick testing. Blood samples were analysed for specific IgG4 and IgE to RUA. Exposure to RUA was estimated based on personal air samples. The relation between IgG4 and newly occurring sensitization or rat allergy was studied in workers who were not sensitized or did not report respiratory symptoms to rats. RESULTS: IgG4 titres were higher in atopic than in non-atopic subjects, and increased with higher allergen exposure. Titres were highest in subjects who were sensitized and reported respiratory symptoms to rats when compared with those who were not (geometric mean [geometric standard deviation] = 202 [5.7] vs. 8.4 [18.3] AU). The association between IgG4 and sensitization or symptomatic rat allergy was independent of estimated allergen exposure. IgG4 was a strong predictor of newly occurring sensitization and symptomatic rat allergy during follow-up in atopic and rat-sensitized subjects. CONCLUSION: High exposure to RUA is associated with a strong allergen-specific IgG4 antibody response. High anti-RUA IgG4 is a strong predictor of prevalent and incident sensitization and symptomatic rat allergy in atopic and rat-sensitized subjects. IgG4 can therefore not explain the absence of a dose response between allergen exposure and allergy in long-term-exposed workers. We consider anti-RUA IgG4 to be a marker that combines aspects of exposure and susceptibility.  相似文献   
997.
AIM:ToinvestigatethepathogenesisofAβ42yieldingandnewdrugtargetsaswellasthepossibilityofRNAinterference(RNAi)techniquefortreatmentofAlzheimerdisease(AD).METHODS:HumanADpresenilin1(PS1)cDNAsequencewasobtainedfromNCBIwebsite.ThethreesitesofRNAiactionandonemissensecontrolsitewereselectedinPS1cDNAthroughonlinedesignofAmbioncompany.Toconfirmspecificityofthesesites,weconductedaBLASTsearchoftheIMAGEESTlibrary.Thecorrespondingdouble-strandedDNAwasusedtoconstructpSilencer3.1-H1p…  相似文献   
998.
Wilson disease (WD) is a hereditary disorder, with recessive transmission and genetic heterogeneity. Several mutations of ATP7B, the gene underlying WD, were reported in many ethnic groups. In this study, mutation screening in ATP7B of 56 Saudi Arabian WD patients was undertaken. The clinical data of all patients were recorded. The entire ATP7B coding sequence, including intron-exon boundaries were screened for mutation by the polymerase chain reaction (PCR)-based mutation detection technique and DNA sequencing. Thirty-nine patients were symptomatic at presentation and 17 subjects were pre-symptomatic siblings of affected patients. Fourteen patients had neurological, 11 patients had mixed (hepatic and neurological), and 14 patients had hepatic presentations. Family history suggestive of WD was present in 72% of cases and 68% had consanguineous parents. Genetic analysis showed disease-causing mutations in three exons (exons 8, 19 and 21) of the ATP7B gene in 28 patients (50%). Mutations in exons 21 (18 cases) and 19 (one case) were unique for Saudis. This large series of Saudi patients with WD has shown wide variability in the genomic substrate of WD. There is no correlation between genotype and clinical presentation.  相似文献   
999.
Myositis is a rare complication following renal transplantation and is most commonly the result of drug-mediated myotoxicity. Other causative disorders include viral infection, electrolyte imbalance and myositis of autoimmune origin. We describe a 60-year-old patient who developed acute polymyositis 4 weeks after a 000 human leukocyte antigen (HLA) mismatch cadaveric renal transplant. Following an uncomplicated transplant course with maintenance triple immunosuppression (prednisolone, mycophenolate mofetil and cyclosporine), the patient presented with severe symmetrical proximal muscle weakness associated with a rise in serum creatine kinase to 46800 U/L. Electromyography confirmed myopathic changes and muscle biopsy demonstrated extensive muscle-fiber necrosis with an inflammatory infiltrate. There were no obviously culpable drugs and viral studies were negative. Prompt initiation of high-dose steroid therapy led to clinical and biochemical recovery. Acute polymyositis may occur following renal transplantation. Potential mechanisms include viral antigen transmission or a localized form of graft vs. host disease.  相似文献   
1000.
目的 克隆人野生型parkin基因并构建真核表达载体pCDNA3.1—parkin,将重组质粒转染PC12细胞获得高表达人野生型parkin基因的PC12细胞克隆。方法 从胎脑组织中提取总RNA,用RT—PCR方法获得人野生型parkin基因的全长cDNA,插入pCR2.1—TA克隆载体中进行序列测定,测序正确后将其亚克隆至表达载体pCD—NA3.1,利用脂质体将重组质粒转染PC12细胞,经G418筛选获得抗性细胞克隆,采用RT—PCR和Western Blot方法鉴定人野生型parkin基因在PC12细胞中的过表达。结果 经限制性内切酶酶切图谱分析和DNA序列测定证实目的基因已插入重组质粒,RT—PCR和Western Blot证明经G418筛选得到的转基因PC12细胞克隆中存在人野生型parkin基因的表达。结论 成功构建了人野生型parkin基因的真核表达载体,获得了稳定表达人野生型parkin基因的PC12细胞克隆,为进一步研究parkin的生物学功能以及parkin在帕金森病发病机制中的作用奠定了良好的基础。  相似文献   
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