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51.
目的 探讨MRI、视诱发电位(VEP)和视野(Vision Field,VF)在视神经炎中的临床应用价值。方法 临床诊断为视神经炎者60例分别行MRI、VEP和视野检查,每例所有检查均在一周内完成,并将检查结果进行统计学处理和分析。结果 MRI阳性率最高(96.67%),其次是视野和VEP(86.96%和75.58%)。同时发现MRI具有定位和一定的鉴别诊断作用。结论 VEP和VF结合MRI检查,三者相辅相成,将有助于视神经炎更早、更准确地诊断和治疗。  相似文献   
52.
羧乙基锗倍半氧化物(Ge—132)能促进培养乳鼠心肌细胞DNA和RNA的合成,提高超氧化物歧化酶(SOD)的活性,维持细胞膜结构的稳定。异丙基肾上腺素可使心肌细胞乳酸脱氢酶(LDH)释放增加,细胞搏动停止,超微结构显示肌膜和线粒体严重受损。Ge—132可显著减少异两基肾上腺素引起心肌细胞释放LDH,维持细胞的搏动功能和超微结构的完整。  相似文献   
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AimsPotassium (K+) channels have been demonstrated to play a prominent involvement in nociceptive processing. Kir7.1, the newest members of the Kir channel family, has not been extensively studied in the CNS, and its function remains largely unknown. The present study investigated the role of spinal Kir7.1 in the development of pathological pain.Methods and ResultsNeuropathic pain was induced by spared nerve injury (SNI). The mechanical sensitivity was assessed by von Frey test. Immunofluorescence staining assay revealed that Kir7.1 was predominantly expressed in spinal neurons but not astrocytes or microglia in normal rats. Western blot results showed that SNI markedly decreased the total and membrane expression of Kir7.1 in the spinal dorsal horn accompanied by mechanical hypersensitivity. Blocking Kir7.1 with the specific antagonist ML418 or knockdown kir7.1 by siRNA led to mechanical allodynia. Co‐IP results showed that the spinal kir7.1 channels were decorated by SUMO‐1 but not SUMO‐2/3, and Kir7.1 SUMOylation was upregulated following SNI. Moreover, inhibited SUMOylation by GA (E1 inhibitor) or 2‐D08 (UBC9 inhibitor) can increase the spinal surface Kir7.1 expression.ConclusionSUMOylation of the Kir7.1 in the spinal cord might contribute to the development of SNI‐induced mechanical allodynia by decreasing the Kir7.1 surface expression in rats.  相似文献   
55.
Bronchiolitis generally refers to inflammation and/or fibrosis of the non-cartilaginous small airways located approximately from the 8th airway generation down to the terminal and respiratory bronchioles. In contrast to young children, the frequency of small airway infection in adult bronchiolitis appears less frequent and a number of other pathophysiological conditions have been implicated in adult bronchiolitis. However, little information is available on the exact medical burden of bronchiolitis such as its prevalence and comorbidities in the adult population. The aim of this study is to elucidate the prevalence and comorbidities of bronchiolitis. We used the Korea National Health Insurance Service-National Sample Cohort, which provides data for 1,000,000 individuals out of the entire population by 2% stratified random sampling according to age, sex, residential area, and level of household income. We defined the cause of bronchiolitis other than acute infection as a patient with diagnostic code J448 or J684 and over 20 years of age who visited a clinic or hospital in South Korea. Then, 1:1 propensity score matching was performed to define a non-bronchiolitis (control) group to compare the comorbidities and mortality in the 2 groups. The overall prevalence of bronchiolitis was 688 cases/1,000,000 population during the study period (95% confidence interval, 625–751). The most common comorbid clinical condition in adults with bronchiolitis was rhinitis (52.3%), followed by bronchial asthma (52.23%), hypertension (43.69%), gastroesophageal reflux disease (30.56%), sinusitis (28.72%), diabetes (22.77%), and osteoporosis (17.85%). Other common bronchiolitis-associated comorbidities were cerebrovascular disease (16.86%), angina (14.37%), peripheral vascular disease (13.42%), congestive heart failure (11.9%), and malignancy in any organ (10.6%). Healthcare costs for bronchiolitis increased steeply during the same period. Malignancy in any organ was the leading cause of mortality in the patient group, followed by bronchiolitis itself. Further larger prospective multiethnic cohort studies should be carried out in the near future.  相似文献   
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The Sn-Ag-Cu (SAC) solder alloys with a low Ag (Ag < 3 wt.%) content have attracted great attention owing to their low cost, increased ability in bulk compliance, and plastic energy dissipation. However, some of their mechanical properties are generally lower than the SAC alloys with a higher Ag content. Adding alloying elements is an effective approach for improving the mechanical properties of the SAC alloys. In this study, the effect of Bi, Sb, and Ti on Sn-1 wt.%Ag-0.5 wt.%Cu (SAC105) solder alloys was investigated. The SAC solders with four compositions: SAC105-1 wt.%Bi, SAC105-1 wt.%Sb, SAC105-1 wt.%Bi-1 wt.%Sb, SAC105-1 wt.%Bi-1 wt.%Sb-0.4 wt.%Ti were prepared. The microstructure and phase compositions were characterized using electron scanning microscopy, and X-ray diffraction. The thermal properties and wettability were also examined. Uniaxial tensile tests and nano-indentation tests were conducted to evaluate the mechanical properties. The results show that adding Bi or Sb could increase the strength of SAC105 alloys mainly due to the solid solution strengthening effect. The creep resistance of SAC105 alloys was also improved with the additions of Bi and Sb. The co-additions of Bi and Sb into SAC105 alloys exhibit an enhanced creep resistance than that calculated by the theoretical calculation. The further addition of Ti into SAC105-1Bi-1Sb alloys demonstrated a much-improved creep resistance, which could be attributed to the synergistic effects of both solid solution strengthening and the precipitation hardening effects.  相似文献   
58.
目的 比较超声检查和病理测量甲状腺乳头状癌(papillary thyroid carcinoma,PTC)肿瘤大小的差异,并分析其临床意义。方法 选取2012年6月~2014年6月杭州市第一人民医院收治的PTC 114例(共122枚癌灶),所有癌灶大小先后通过术前超声检查和术后组织病理测量确定,采用Pearson相关分析、配对t 检验和Bland-Altman作图评价两种方法测量肿瘤大小的差异性和一致性。结果  Pearson相关显示两种方法测量的肿瘤最大径存在显著正相关(r =0.957,P =0.000)。配对t 检验显示肿瘤的超声最大径(8.24±5.06)mm与病理最大径(7.79±4.75)mm存在显著性差异。Bland-Altman分析显示,两种方法测量的肿瘤最大径的差值绝对值介于0~6.5 mm之间,平均(1.03±1.14)mm,差值的一致性界限(l imit s of agreement,LoA)为-2.41 mm~3.33 mm,LoA的95%置信区间为-2.87 mm~3.78 mm,LoA置信区间范围内差值的最大绝对值为2.9 mm。结论 超声检查和病理测量PTC的肿瘤大小存在显著差异,两者的一致性欠佳,临床实践中应引起重视。  相似文献   
59.
目的 探讨牵引成骨技术在颌骨畸形继发阻塞性睡眠呼吸暂停低通气综合征(obstructivesleepapnea hypopneasyndrome,OSAHS)治疗中应用的效果。方法 收集自 1 997年 1 0月~2 0 0 2年 9月共 46例颌骨畸形伴OSAHS少年儿童 ,患者睡眠呼吸障碍经夜间多导睡眠监测证实。年龄从 4~ 1 8岁 ,平均年龄 1 1 4岁 ,其中颞下颌关节强直伴小下颌畸形 32例 ;小下颌畸形患者 9例 ;第一、二鳃弓综合征 2例 ;Crouzon综合征 3例。患者术前常规拍照、摄头颅定位侧位片 ,全景片。每位患者根据畸形情况 ,采取单侧或双侧牵引成骨治疗 ,根据侧位片预测 ,一般牵引到略微反覆盖为准。牵引幅度为 5~ 35mm ,平均牵引幅度 1 8 34mm。比较患者术前后颅颌面形态、呼吸道测量分析、多导睡眠监测结果评价治疗效果。结果 患者术后颌骨畸形明显改善 ,头影测量分析提示上呼吸道狭窄得以显著缓解 ,最小后气道径 ( x±s)由 (5 48± 2 76)mm增加到 (9 97± 2 0 5)mm ,睡眠呼吸暂停低通气指数 (apnea hypopneaindex,AHI, x±s)从术前 (66 31± 1 7 1 5)次 /s降低到 (3 1 6± 1 70 )次 /s,以上结果统计分析表明差异具有非常显著性 (P <0 0 0 1 )。结论 牵引成骨治疗颌骨畸形继发OSAHS患者具有很好的疗效  相似文献   
60.
目的:筛选火绒草中的抗炎活性部位。方法:采用系统溶剂法按照极性由低到高的顺序分离得到火绒草石油醚提取物、乙酸乙酯提取物、正丁醇萃取物、水提取物。采用酶联免疫法(ELISA)建立花生四烯酸(AA)的5-脂氧合酶(5-LOX)体外代谢途径,检测火绒草提取物抑制5-LOX活性的能力。结果:火绒草乙酸乙酯提取物对5-LOX活性有76.92%强度的抑制作用。结论:火绒草乙酸乙酯提取物具有较强的抗炎活性,可作为潜在的抗炎活性成分筛选药物。  相似文献   
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