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51.
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The spectral response curve (amplitude versus wavelength) of the R2 of the early receptor potential (ERP) was studied in normal, protan, and deutan subjects. The R2 amplitude peaked at 520nm in most normal subjects. The R2 at long wavelengths was smaller than normal in protans and larger than normal in deutans when the maximum amplitudes were normalized to 100% at the peak. The ratio of the R2 amplitude at 460 nm to that at 600 nm clearly differed between protans and deutans. The ERP and the rapid off-response, which is mainly due to the cessation of the late receptor potential, were recorded in the same subjects. The ratio of the sensitivity of the rapid off-response at 500 nm to that at 600 nm was correlated with the ratio of the R2 amplitude at 460 nm to that at 600nm (correlation coefficient, 0.823, p < 0.001). This study, in conjunction with our previous study, indicates that the abnormality is in the outer segments of the cones in protans and deutans.  相似文献   
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目的探讨自然流产模型小鼠绒毛滋养层细胞凋亡异常与自然流产的关系。方法建立正常妊娠模型CBAXBALB/c和自然流产模型CBAXDBA/2。采用DNA缺口原位末端标记技术(TUNEL)测定两组模型孕13 d绒毛滋养层细胞凋亡情况;免疫组织化学SABC法测定两组模型孕13 d绒毛组织Bcl-2、Bax、Fas、FasL 4种凋亡调控蛋白的表达,并以MBIS-2000医用彩色病理图像免疫组织化学测量系统对其表达进行半定量分析,结果用平均灰度值表示。结果自然流产模型小鼠绒毛滋养层细胞凋亡指数明显高于正常妊娠模型(P<0.01)。Bax表达亦高于正常妊娠模型(P<0.05);FasL表达低于正常妊娠模型(P<0.01);Fas和Bcl-2表达两组无明显差异。结论早孕期绒毛滋养层细胞凋亡异常是自然流产机制之一,Bcl-2/Bax,Fas/FasL途径可能是诱导早孕期绒毛滋养层细胞凋亡的重要因素。  相似文献   
55.
Endoscopic submucosal dissection (ESD) for colorectal cancer is not widely accepted because of its technical difficulty and the risk of perforation. In addition, the risk of peritonitis cannot be completely eliminated even if a perforation is closed successfully. Reported here are two cases of early colon cancer in which the patients sustained iatrogenic perforations of the ascending colon during conventional endoscopic mucosal resection and of the sigmoid colon during ESD, respectively, requiring abdominal decompression with an 18 G Medicut needle. Both of these perforations were successfully treated by endoscopic clipping. In conclusion, conservative medical management may be possible in patients who have undergone successful closure of colonic perforations using endoscopic clipping. In order to perform immediate endoscopic closure, abdominal decompression has been useful to decrease patient discomfort and colonic lumen collapse. Now, CO2 insufflation is being used effectively for the prevention of pneumoperitoneum.  相似文献   
56.
下颈椎骨折脱位伴关节突交锁的治疗策略选择   总被引:1,自引:0,他引:1  
[目的]探讨并评估在下颈椎骨折脱位伴关节突交锁时安全、简便和有效的治疗策略。[方法]对16例创伤性下颈椎骨折脱位伴关节突交锁的患者于清醒状态及X线透视机监视下先行早期持续闭合颅骨牵引复位。所有患者在治疗前均行X线片和MRI/CT检查及ASIA神经功能评级。持续闭合牵引复位时行动态ASIA神经功能评级及X线透视机监视。损伤至开始牵引复位的间隔平均为31 h(6~52 h)。复位成功后维持颅骨牵引并择期行颈前路或颈前后路联合手术。9例患者于复位成功后再次行MR I扫描。[结果]治疗前MRI显示分别有8例和5例患者存在脱位节段的椎间盘突出和损坏;ASIA神经功能评级分别为:C级7例,D级5例,E级4例。16例患者均闭合复位成功且无一例出现神经功能恶化。复位成功后再次MRI扫描显示:6例脱位节段的椎间盘突出中有2例接近自动回纳,4例仍维持原样;3例脱位节段的椎间盘损坏中有2例维持原样,另1例转变为椎间盘突出。平均牵引重量为19 kg(10~32kg),平均牵引时间为53 min(30~135 min)。[结论]当患者处于清醒及检体合作的状态下通过动态神经功能评级及X线透视机监视,对下颈椎骨折脱位伴关节突交锁行早期持续闭合颅骨牵引复位,择期根据全身及局部状况行颈前路或颈前后路联合手术是一种安全、简便和有效的治疗策略。  相似文献   
57.
[目的]探讨外伤性胸椎间盘突出症的临床表现、早期诊断及手术治疗效果。[方法]2000年6月-2005年6月共收治外伤性胸椎间盘突出症患者11例,其中男8例,女3例,年龄15-38岁,平均23.96岁。诊断时间距外伤时间最短的为2d,最长的8个月,平均4.1个月。早期明确诊断后行经关节突入路胸椎间盘摘除术。[结果]11例患者获得1、1-3.8年术后随访,平均随访2.6年。根据Otani’s等分级方法进行疗效评价:优7例,良3例,可1例,差0例,失败0例。手术优良率为90.91%。[结论]外伤性胸椎间盘突出较少见,无典型临床表现,本症的早期诊断及早期手术治疗是远期优良疗效的保证。  相似文献   
58.
Aim: The purpose of this project was to operationalize and apply a previously identified set of performance measures designed to evaluate services for those experiencing a first episode of a schizophrenia spectrum disorder. Methods: Operational definitions were developed for previously identified measures through an iterative process of discussions between clinical experts and health‐care evaluators. Data were collected from existing sources including corporate databases, clinical databases and chart review. Results: Definitions were developed for 44 measures covering seven of eight domains recommended for service level evaluation by the Canadian Institute for Health Information domains. Forty measures could be calculated. Conclusions: The measures represent a comprehensive set of performance measures suitable for the evaluation of services for people with a first‐episode psychosis. The measures could be used by other services in order to establish standards and norms for routine clinical practice.  相似文献   
59.
Aim: This article reviews research centred around juvenile bipolar disorder with particular reference to diagnostic difficulties. Putative deficits are scrutinized with respect to trait likelihood and the roles of neuropsychology and neuroimaging in enhancing our understanding of juvenile bipolar disorder are discussed. Methods: Search terms including childhood, adolescent, youth and juvenile combined with the terms ‘bipolar disorder’, mania, depression and hypomania were used to identify relevant studies in MEDLINE and PsychLit. Results: Over recent years research into this relatively new disorder has increased phenomenally. Key issues within the field include diagnostic specificity, the heritability of the disorder, the impact of comorbidity and the implications of neuropsychological and neuroimaging findings. Conclusion: Despite concerning controversies in literature the diagnosis of bipolar disorder in children and adolescents as compared with adults, promising future research directions include better neurological characterization of the disorder through the application of findings from clinical populations, neuropsychological and neuroimaging research.  相似文献   
60.
桂建伟 《实用预防医学》2005,12(6):1430-1431
目的 探讨药物流产后阴道出血的原因,对临床治疗提供依据。方法 对108例停经时间≤49d,尿β-HCG阳性,经超声检查为宫内妊娠,试行药物流产后出血≥14d的患者作为观察对象。结果 108例药物流产后出血的患者中73例经病理检查证实为不全流产占67.59%。结论 药物流产后长时间出血的患者中,最主要原因为不全流产,其次为子宫内膜炎。  相似文献   
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