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91.
汉语阅读障碍儿童在本顿视觉保持测验中的反应特征   总被引:1,自引:0,他引:1  
目的:比较阅读障碍儿童与正常儿童在本顿视觉保持测验中的反应特征,探索阅读障碍儿童视觉空间记忆能力的特点。方法:①2005-07/2006-05在儿童发育行为门诊遴选阅读障碍儿童20名(平均年龄10.2岁),按1∶1配对原则,选择年龄、性别、年级和家庭状况等条件与阅读障碍组相似的20名正常阅读能力儿童为对照组(平均年龄10.1岁)。②应用国内修订版本顿视觉保持测验C式B法,D式C法和E式D法对两组儿童进行个别测试。C式图卡呈现5s后让被试默画(视觉记忆能力),D式图卡让被试临摹(视觉结构能力),E式图卡呈现10s后间隔15s再让被试默画(视觉延迟记忆能力)。③对两组儿童的视觉记忆保持能力、视觉结构能力和延迟记忆能力进行测试,分别记录两组儿童测验的正确分(每一图卡根据全或无的原则记1或0分,总分0~10)及错误次数(错误类型分为遗漏或增加、变形、持续、旋转、位置错误和大小错误6个范畴),进行配对t检验。结果:40名受试者均进入结果分析。①正确得分:在视觉记忆和视觉结构能力测验中阅读障碍组低于对照组(5.00±2.45,6.60±1.82,P=0.019;7.50±2.44,8.95±1.32,P=0.015),在视觉延迟记忆测试中,两组得分比较差异不显著(P=0.077)。②总错误分:在视觉记忆和视觉结构能力测验中阅读障碍组高于对照组(7.65±4.20,4.90±3.24,P=0.016;3.20±3.93,1.15±1.46,P=0.035),在视觉延迟记忆测试中,两组得分比较差异不显著(P=0.389)。③错误类型:阅读障碍组儿童在视觉记忆能力测试中变形和持续性错误次数均显著多于对照组(3.95±2.40,1.75±1.52;0.35±0.67,0;P均<0.05),在视觉结构能力测试中变形错误次数显著多于对照组(1.35±1.69,0.35±0.75,P<0.05)。结论:阅读障碍儿童的视觉空间短时记忆能力、视觉结构和视觉运动整合能力存在缺陷。  相似文献   
92.
Hepatitis C virus among blood donors: follow-up study   总被引:1,自引:0,他引:1  
BACKGROUND: The exact significance of antibodies to hepatitis C virus (HCV) in blood donors remains unknown. Confirmatory tests of anti-HCV- reactive serum and HCV RNA by polymerase chain reaction (PCR) are used to refute a large proportion of false-positive results. STUDY DESIGN AND METHODS: Ninety-two blood donors who were anti-HCV reactive in a first-generation enzyme-linked immunosorbent assay (ELISA) were reevaluated 10 months later with a second-generation ELISA (ELISA-2) as well as with second-generation recombinant immunoblot assay (RIBA-2) and by PCR. RESULTS: Twenty-five (43.9%) of the 57 ELISA-2-positive donors were confirmed as positive by RIBA-2; of these, 84 percent were HCV RNA positive in PCR. Of the 57 who were still anti-HCV positive, 46 were followed up and tested again in the same manner 2 years after the first screening. At that time, the pattern was little changed: 94 percent of RIBA-2- and PCR-positive donors remained positive. Of RIBA-2- and PCR-positive blood donors, 62 percent had abnormal alanine aminotransferase levels in at least one of the three evaluations. Among the anti-HCV-positive donors confirmed by RIBA-2, 60 percent, versus 12.6 percent in the control group, had a significantly (p < 0.001) more frequent risk factor for HCV infection, due to parenteral exposure to blood. CONCLUSION: These data confirm a good correlation between RIBA-2 reactivity and the detection of HCV RNA in a population of anti-HCV- positive blood donors.  相似文献   
93.
The development of efficacious prophylactic human papillomavirus vaccines provided an opportunity for the primary prevention of related infections and diseases. Certain oncogenic human papillomaviruses that preferentially infect the genital epithelium cause cervical cancer and a substantial proportion of anal, penile, vaginal, vulvar and oropharyngeal cancers. Following extensive clinical trials demonstrating their efficacy and safety, two vaccines have been in global use for over 6 years. This review summarises the accumulated evidence regarding their high level of efficacy, safety in population usage, reductions in genital warts, infections and cervical disease following their adoption, and facilitators and barriers to achieving high vaccination coverage. The review also discusses practical issues and frequently asked questions regarding duration of effect, vaccination of women treated for cervical disease and alternate vaccination schedules, as well as the need to review cervical screening strategies in the post‐ vaccination environment.  相似文献   
94.
Lack of clinical significance of "enzyme-only" red cell alloantibodies   总被引:1,自引:0,他引:1  
In a retrospective study on samples from 10,000 recently transfused patients, 35 samples were found to contain an antibody that reacted with ficin-treated red cells but was not demonstrable by low-ionic- strength saline solution and indirect antiglobulin test (LISS-IAT). In those 35 patients, the specificity of the antibody was such that each patient would have been transfused with antigen-negative blood had the antibody reacted in LISS-IAT. Tests on red cells from the units already transfused showed that 19 patients had among them received, by chance, 32 antigen-positive and 74 antigen-negative units. The remaining 16 patients had among them received 57 units that were, again by chance, all antigen negative. One patient given antigen-positive blood suffered a delayed transfusion reaction; in two others the antibodies became LISS-IAT active after transfusion. However, similar changes to the LISS- IAT-active state were seen with two antibodies of patients given only antigen-negative blood. Also found in the 10,000 patients were 28 clinically insignificant antibodies, 77 sera in which the antibody was too weak to identify, and 216 autoantibodies that reacted only with ficin-treated red cells. These data support a belief, generally held in the United States but not necessarily elsewhere, that the use of protease-treated red cells for routine pretransfusion tests creates far more work than the accrued benefits justify.  相似文献   
95.
保证输血时血清学方面的安全,首要的是对受血者与献血者ABO血型定型,血清学检查通常分两个步骤.正定型通常使用鼠源单克隆抗体检测红细胞表面是否存在A或B抗原.互补的实验即反定型,利用当红细胞上缺乏A或B抗原时,人群可天然产生相对应的抗体的原理,检测血清中是否存在抗-A或者抗-B抗体.确定了受血者红细胞表面的ABO抗原以及血浆中的抗体,便能确定血型,为其提供相合的血液.  相似文献   
96.
OBJECTIVES: The aim of this study was to review a large series of ameloblastomas, accessioned during a period of 35 years in a single Oral Pathology Diagnostic Center, for the incidence of desmoplastic ameloblastoma (DA) and in order to analyze the clinical features of this unusual variant.
MATERIALS AND METHODS: All cases diagnosed as ameloblastoma were reviewed and 14 were rediagnosed as DA. These cases were analyzed in terms of gender, patient age, location, clinical diagnosis, radiographic features and recurrence following treatment. Data from DA and non-desmoplastic ameloblastoma (NDA) were compared.
RESULTS: The incidence of DA in this series was 8.8%. The mean age of NDA and DA were 39.1 and 38.8 years respectively, and a higher female prevalence was observed in the latter. The mandible was the most affected bone in both groups of tumors, but with a different regional distribution. Most NDA arose in the angle and ramus of the mandible, but the premolar/molar region was the preferential location for DA. The most common radiographic feature in DA was the osteolytic type, either monolocular or multilocular. Most of these cases were clinically diagnosed as ameloblastoma. According to follow-up data available, 21.4% of DA and 10.1% of NDA recurred.
CONCLUSIONS: The results of this study do not support the hypothesis that DA should be a separate clinicopathological entity. It seems most likely that DA is another his-tologic variant of ameloblastoma.  相似文献   
97.
Ofuji papuloerythroderma is an uncommon entity of unknown aetiology, characterized by a pruritic eruption of widespread, red–brown, flat papules that leads to spare skin folds. A number of cases have been described associated with tumour pathology, mainly cutaneous T‐cell lymphomas. We report a new case of Ofuji papuloerythroderma evolving to cutaneous T‐cell lymphoma in an 85‐year‐old woman who had been previously diagnosed with papuloerythroderma 7 years previously.  相似文献   
98.
99.
BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo.  相似文献   
100.
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