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31.
RELATIONSHIP BETWEEN HUMAN PARVOVIRUS B19 INFECTION AND APLASTIC ANEMIA   总被引:2,自引:0,他引:2  
Objective. To explore the relationship between human parvovirus B19 (HPV B19) infection and aplastic anemia (AA) and to investigate the role of HPV B19 in the occurrence of AA. Methods. The presence of HPV B19 DNA was detected in the peripheral blood samples of 60 patients with AA (children 38 and adults 22) by nested polymerase chain reaction (PCR) assay, and 30 healthy persons were selected as control. Results. Sixteen (26. 7 % ) of 60 AA cases were HPV B19 DNA positive, while all the samples in the control group were negative for HPV B19 (P = 0. 000914). Among the case group, the positive rates of HPV B19 DNA were21.4% (6 /28), 30.0% (3 / 10), 20.0% (1 /5) and 35.3% (6 / 17) in children acute AA (AAA), children chronic AA (CAA), adults AAA and adults CAA patients respectively, which were significant-ly higher than that in the control group, Furthermore, there was no remarkable difference between children AA and adults AA in the 16 HPV B19 DNA positive patients; neither was there between AAA and CAA. Conclusions. HPV B19 infection is not only correlated with the occurrence of children AAA and CAA, but also with adults AAA and CAA, and might be an important viral cause for AA in humans.  相似文献   
32.
左肺移植的实验研究   总被引:2,自引:0,他引:2  
目的为临床肺移植积累经验。方法分析总结29例犬左肺移植的资料。其中15例的供体肺用Euro-Collings液在4℃下保存6h,14例用UW液保存22~25h,作同种异体移植,并阻断受体的右肺动脉,以测定移植左肺的功能。结果所有的移植左肺均能胜任气体交换,循环稳定。结击本左肺移植方法可靠,可供临床应用时参考。  相似文献   
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The patient in this case is an 11-year-old girl, whose mandibular left canine was transmigrated. The traction to the arch was assisted by using a temporary skeletal anchorage device. After 5 months of poor response to traction, the biomechanics were re-adjusted, obtaining effective traction in to the arch in 12 months. After this period, the treatment was completed with fixed orthodontic appliances.  相似文献   
36.
BackgroundMaxillary canines are considered the most commonly impacted teeth, after the third molars. Orthodontists have different preferences on how to approach maxillary impacted canines (MIC). The objective of this article was to investigate orthodontists’ approach to managing MIC.Material and methodsA cross-sectional study comprising a comprehensive survey with 22 questions was sent to practicing orthodontists. This study explored the preferred diagnostic measures, surgical techniques, materials, and mechanics utilized to manage MIC;104 responses were returned.ResultsPalatal impaction was reported to be encountered more often than labial impaction by 60% of the respondents. In 62% of the respondents, an oral and maxillofacial surgeon was the specialist preferred to perform the surgical exposure. In 66%, the choice of required surgical techniques was reported as a joint decision between orthodontists and other specialists who perform the surgery. Cone-beam computed tomography (CBCT) was reported to be the diagnostic x-ray of choice. The gold button with a chain was the preferred bonded attachment in 86% of cases. Less than half of the respondents bonded the attachments themselves during surgical exposure. A clear plastic retainer was the preferred retainer in 61% of the respondents, and 43% of the respondents tended to use a closed exposure technique. Coe-pakTM was the preferred surgical pack for orthodontists who prefer an open exposure technique. Piggyback (double wire) was the preferable mechanic to move a palatally impacted canine.ConclusionOur findings indicate that there are variations among orthodontists on how to manage MICs in terms of diagnostic methods, surgical management, materials, and mechanics.  相似文献   
37.
ObjectivesTo describe the endodontic orthograde retreatment of a lower canine with a rare anatomy, affected by a symptomatic periapical lesion.Materials and methodsA 30-year-old Caucasian woman came to our office reporting severe pain and swelling located at the right mandible. A two-roots/two-canals configuration was discovered for the lower canine which sustained the periapical infection; a missed lingual canal was not recognized and treated at the previous primary endodontic therapy.A full pre-operative examination and diagnosis, the application of modern endodontic strategies along with the use of magnification technologies (like the Surgical Operating Microscope - SOM) and proper disinfection protocols were employed for endodontic re-treatment.Result and conclusionsHealing of the periapical infection was clinically and radiographically confirmed at a 9-month follow-up. Endodontists should know the anatomical variations of human teeth and be vigilant about them when approaching treatments. More than a single radiographic projection is recommended in the diagnostic phase.Careful procedures related to instrumentation, cleaning and filling of the entire root canal system enhance the potential for healing of apical lesions.  相似文献   
38.
Human parvovirus B19 (HPV B19) infections are usually asymptomatic or benign and self-limiting. In immunocompromised patients and patients with chronic hemolytic anemia, it can lead to transient red cell aplasia. Few reports in the literature have implicated HPV B19 as the possible cause of acute hepatitis and severe aplastic anemia in immunocompetent patients. Here, the authors report a previously healthy 6-year-old girl with acute hepatitis and severe aplastic anemia associated with HPV B19 infection diagnosed by serology (ELISA). Other common causes of these manifestations were ruled out. The clinical manifestations subsequently improved significantly with the use of immunosuppressive therapy confirming an autoimmune mechanism.  相似文献   
39.
目的:探讨我国西北地区血液系统疾病患儿人细小病毒B19(HPV B19)感染情况及两者的相关性。方法:对特发性血小板减少性紫癜、再生障碍性贫血和白血病患儿的外周血分别采用PCR方法检测HPV B19-DNA和ELISA方法检测HPV B19-IgG。结果:特发性血小板减少性紫癜患儿HPV B19-IgG阳性率为43.08%(28/65),白血病患儿HPV B19-IgG阳性率为41.07%(46/112),病例组较对照组比较有极显著性差异(P<0.01);再生障碍性贫血患儿HPV B19-IgG阳性率为21.43%(6/28),病例组较对照组比较有显著性差异(P<0.05)。65例特发性血小板减少性紫癜患儿HPV B19-DNA阳性率为40.00%(26/65);28例再生障碍性贫血患儿HPV B19-DNA阳性率为21.43%(6/28);112例白血病患儿HPV B19-DNA阳性率为27.68%(31/112);对照组HPV B19-DNA检测均为阴性。结论:HPV B19感染与我国西北地区部分血液系统疾病患儿发病相关。  相似文献   
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