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31.
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   
32.
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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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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Tuberous Sclerosis Complex (TSC) is a multisystemic condition caused by mutations in TSC1 or TSC2, but a pathogenic variant is not identified in up to 10% of the patients. The aim of this study was to delineate the phenotype of pediatric and adult patients with a definite clinical diagnosis of TSC and no mutation identified in TSC1 or TSC2.We collected molecular and clinical data of 240 patients with TSC, assessing over 50 variables. We compared the phenotype of the homogeneous group of individuals with No Mutation Identified (NMI) with that of TSC patients with a TSC1 and TSC2 pathogenic variant.9.17% of individuals were classified as NMI. They were diagnosed at an older age (p?=?0.001), had more frequent normal cognition (p <?0.001) and less frequent epilepsy (p =?0.010), subependymal nodules (p?=?0.022) and giant cell astrocytomas (p?=?0.008) than patients with TSC2 pathogenic variants. NMI individuals showed more frequent bilateral and larger renal angiomyolipomas (p?=?0.001; p?=?0.003) and pulmonary involvement (trend) than patients with TSC1 pathogenic variants. Only one NMI individual had intellectual disability. None presented with a subependymal giant cell astrocytoma. Other medical problems not typical of TSC were found in 42.86%, without a recurrent pattern of abnormalities. Other TSC-associated neuropsychiatric disorders and drug-resistance in epilepsy were equally frequent in the three groups.This study provides a systematic clinical characterization of patients with TSC and facilitates the delineation of a distinctive phenotype indicative of NMI patients, with important implications for surveillance.  相似文献   
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Primary Autosomal Recessive Microcephaly (MCPH) is characterized by congenital microcephaly usually without additional clinical findings. The most common gene implicated in MCPH is ASPM and a large percentage of mutations described have been homozygous and in consanguineous families primarily of East Asian and Middle Eastern origin. ASPM sequencing was performed on 400 patients between the years 2009 and 2012. Seventy of the patient samples were also analyzed for copy number changes in the ASPM gene. Forty protein truncating mutations, including 29 novel mutations, were identified in 39 patients with MCPH. Approximately one third of patients were compound heterozygotes, indicative of non‐consanguinity in these patients. In addition, 46 non‐synonymous variants were identified and interpreted as variants of uncertain significance. No deletion/duplication in ASPM was identified in the patients analyzed. A wide ethnic distribution was observed, including the first reported patients with ASPM‐related MCPH of Hispanic descent. Clinical information was collected for 26 of the ASPM‐positive patients and 41 of the ASPM‐negative patients. As more individuals are identified with MCPH, we anticipate that we will continue to identify ASPM mutation‐positive patients from all ethnic origins supporting the occurrence of this genetic condition beyond that of consanguineous families of certain ethnic populations.  相似文献   
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