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81.
Scandella  D; Mattingly  M; de Graaf  S; Fulcher  CA 《Blood》1989,74(5):1618-1626
Human factor VIII(FVIII) inhibitors are pathologic, circulating antibodies that inactivate FVIII. We have examined the location of epitopes on the FVIII protein for inhibitors from hemophilia A and nonhemophilic individuals. The inhibitors were of type I or type II in the kinetics of their inactivation of FVIII. A cDNA clone of human FVIII was used to express defined FVIII protein fragments in Escherichia coli for immunoblotting with inhibitor plasma. An epitope for 18 heavy-chain inhibitors was localized to the aminoterminal 18.3 Kd of the A2 domain. Two of these inhibitors also recognized an epitope located between A1 and A2 domains. Similarly, an epitope for 23 light- chain inhibitors was localized to the C2 domain. Weaker epitopes for 13 of the same inhibitors within the C1 and C2 domains were also observed. Four of the 23 inhibitors in addition bound strongly to the A3 domain. Most inhibitors (22 of 23) were neutralized in vitro only by the FVIII fragments to which they bound on immunoblots; however, one inhibitor that was neutralized by a fragment containing the A1 domain did not bind to it on immunoblots. Conversely, 3 of 3 inhibitors that bound to the A3 domain and 5 of 15 that bound to the A2 domain were not neutralized by the corresponding fragments. The epitope specificity of an inhibitor did not depend on its source or type. Our results show that FVIII inhibitors bind to limited areas within the heavy and light chains of FVIII. Some inhibitor plasmas contain additional antibodies that may not be inhibitory.  相似文献   
82.
Cai  SP; Chang  CA; Zhang  JZ; Saiki  RK; Erlich  HA; Kan  YW 《Blood》1989,73(2):372-374
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common.  相似文献   
83.
Foon  KA; Nakano  GM; Koller  CA; Longo  DL; Steis  RG 《Blood》1986,68(1):297-300
Two patients with hairy cell leukemia with massive splenomegaly and severe pancytopenia were treated with recombinant alpha-A interferon (IFN-alpha-2a). There was no significant response to a trial of IFN- alpha-2a (11 and 20 weeks) with respect to blood counts or spleen size. Subsequent treatment with 2'-deoxycoformycin (dCF) for 8 consecutive weeks (4 mg/m2/wk) resulted in normalization of spleen size and a normalization of peripheral blood counts and bone marrow in one patient. The second patient demonstrated a reduction in spleen size and improved blood counts following 9 weeks of dCF therapy but eventually became refractory. This demonstrates that dCF is non-cross-resistant with interferon and confirms the efficacy of dCF in nonsplenectomized patients.  相似文献   
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<正>Multiple studies have reported decreased emergency department(ED) patient volumes during the coronavirus disease(COVID-19) pandemic,[1-6] including areas most affected by the virus.[7]Most existing studies have investigated general trends in ED presentations and have not examined the impact of COVID-19 on different types of EDs, specific ED patient groups, or illness presentations.  相似文献   
87.
牙列缺损的计算机三维建模   总被引:4,自引:5,他引:4  
目的 建立牙列缺损的计算机三维模型。方法 采用表面绘制法,依据CT扫描头颅骨标本获得的二维断层图像数据在3D Studio Max中沿牙体长轴放样、微调并赋以材质,得到牙列缺损的计算机三维模型。结果 能在计算机中方便快速地模拟任意类型的牙列缺损,并可全方位地旋转、放大和缩小。结论 提供了一种牙列缺损三维建模的新方法,有利于三维义齿专家系统的开发和计算机辅助教学。  相似文献   
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89.
目的探讨经关节入路微创钢板固定(MIPPO)技术治疗股骨远端C型骨折的临床疗效。方法2002年4月~2005年2月,应用MIPPO技术治疗股骨远端C型骨折14例,按AO/ASIF分类:C1型3例,C2型6例,C3型5例。先行关节内骨折切开复位、松质骨螺钉固定,再行髁上部分骨折间接复位、经关节内切口插入髁支撑钢板或LISS钢板桥接固定骨折。结果12例患者获得10~32个月(平均18.4个月)随访,骨折均获愈合,愈合时间10周~12个月,平均4.6个月。按Kolmert和Wulff的评价标准:优4例,良5例,可2例,差1例,优良率为75%。结论应用MIPPO技术治疗股骨远端C型骨折实现了微创操作,具有创伤小、软组织干扰少、骨折愈合快等优点,疗效满意。  相似文献   
90.
OBJECTIVES: To determine whether there are racial/ethnic differences regarding the relationship of level of blood pressure to change in cognitive function in older people. DESIGN: Longitudinal data 1986 to 1989 on representative, older, community-residing African Americans and whites. Blood pressure levels were assessed and a brief screen of cognitive functioning, the Short Portable Mental Status Questionnaire (SPMSQ), was performed at baseline and 3 years later. SETTING: Five contiguous counties in the Piedmont area of North Carolina. PARTICIPANTS: African-American (n = 2,260) and white(n = 1,876) participants in the Duke Established Populations for Epidemiologic Studies of the Elderly, aged 65 to 105 at baseline. MEASUREMENTS: The outcome measure was change in SPMSQ score over 3 years. Covariates included age; education; gender; self-reported diabetes mellitus, stroke, heart attack, current smoking, and depressive symptomatology;and use of antihypertensive medication. The primary independent variable was measured blood pressure. RESULTS: In unadjusted analyses, a statistically significant U-shaped relationship was found between systolic (but not diastolic) blood pressure levels and change in SPMSQ score over a 3-year period for older white men and women. No such relationships were found between these blood pressure measurements and change in SPMSQ score in older African Americans. These findings remained after adjustment for initial SPMSQ score, demographic characteristics, and use of antihypertensive medication. There were no significant interactions between race and blood pressure on change in cognitive function. CONCLUSION: Decline in cognitive function was associated with extremes of systolic blood pressure in older white people. Although a similar but muted nonsignificant association was found in older African Americans, the curves for the two groups were not significantly different. Further studies in older African Americans are needed.  相似文献   
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