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61.
Bernard-Soulier syndrome (BSs) is a rare bleeding disorder characterized by circulating giant platelets, thrombocytopenia, and a prolonged bleeding time. BSs usually has an autosomal recessive inheritance pattern, with a preponderance of Caucasian and Japanese ancestry when the ethnic background has been reported. Underlying this disorder of platelet function is a defect in the platelet glycoprotein (GP) Ib-IX-V complex, composed of four polypeptides, GP Ib alpha, GP Ib beta, GP IX, and GP V. Molecular characterization of individuals with BSs has identified mutations in the GP Ib alpha, GP Ib beta, and GP IX genes responsible for the expressed phenotype. In this study, we report a family of African-American descent, with autosomal recessive BSs showing a point mutation in codon 129 of the GP Ib alpha gene. This mutation, CTC:wild-type to CCC:mutant, is similar to that of another African American family where the resulting leucine to proline substitution in the 5(th) leucine-rich repeat of GP Ib alpha is responsible for the observed BSs phenotype. Comparison of the intragenic polymorphisms of GP Ib alpha, as well as microsatellite markers in a 17.5 cM region of chromosome 17p12 that contains the GP Ib alpha gene, suggests that, although socially unrelated, the Leu129Pro mutation in these two families has a common founder.  相似文献   
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PURPOSE: To investigate the effects of the epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) ZD1839 ('Iressa') on the cellular proliferation of androgen-sensitive and androgen-independent human prostatic cancer cell lines and primary cultures in vitro. EXPERIMENTAL DESIGN: In this study, we investigated the effects of the quinazoline ZD1839, a potent, selective EGFR-TKI, on the EGFR autophosphorylation and cellular proliferation of androgen-sensitive (ND1, LNCaP, and ALVA-31) and androgen-independent (PC3, DU145, and TSU-Pr1) human prostatic cancer cell lines and 20 primary cultures derived from human prostatic cancer tissue. RESULTS: EGFR was present and phosphorylated in all cell lines tested. ZD1839 reduced EGFR autophosphorylation in intact cell lines with IC(50)s of 0.46-0.97 microM, and inhibited cellular proliferation with IC(50)s of 0.37-1.03 microM. Constitutive EGFR autophosphorylation was low in primary cell cultures, but addition of EGF (50 ng/ml) caused marked EGFR autophosphorylation; cellular proliferation in the presence of EGF was inhibited by ZD1839 with a mean IC(50) of 0.45 microM. At doses >1 microM, ZD1839 induced apoptosis in both androgen-dependent and androgen-independent PCa cell lines. CONCLUSION. Our experiments suggest that EGFR-TKIs such as ZD1839 may have potential in blocking the growth and progression of human prostatic cancers even in early phases of the disease.  相似文献   
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International Journal of Mental Health and Addiction - Even though positive associations among problematic Internet use (PIU), maladaptive personality traits, insecure attachment styles, and...  相似文献   
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Congenital heart defects affect 60-85% of patients with RASopathies. We analysed the clinical and molecular characteristics of atrioventricular canal defect in patients with mutations affecting genes coding for proteins with role in the RAS/MAPK pathway. Between 2002 and 2011, 101 patients with cardiac defect and a molecularly confirmed RASopathy were collected. Congenital heart defects within the spectrum of complete or partial (including cleft mitral valve) atrioventricular canal defect were diagnosed in 8/101 (8%) patients, including seven with a PTPN11 gene mutation, and one single subject with a RAF1 gene mutation. The only recurrent mutation was the missense PTPN11 c.124 A>G change (T42A) in PTPN11. Partial atrioventricular canal defect was found in six cases, complete in one, cleft mitral valve in one. In four subjects the defect was associated with other cardiac defects, including subvalvular aortic stenosis, mitral valve anomaly, pulmonary valve stenosis and hypertrophic cardiomyopathy. Maternal segregation of PTPN11 and RAF1 gene mutations occurred in two and one patients, respectively. Congenital heart defects in the affected relatives were discordant in the families with PTPN11 mutations, and concordant in that with RAF1 mutation. In conclusion, our data confirm previous reports indicating that atrioventricular canal defect represents a relatively common feature in Noonan syndrome. Among RASopathies, atrioventricular canal defect was observed to occur with higher prevalence among subjects with PTPN11 mutations, even though this association was not significant possibly because of low statistical power. Familial segregation of atrioventricular canal defect should be considered in the genetic counselling of families with RASopathies.  相似文献   
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Clinical Oral Investigations - The aim of the present study was to investigate whether peri-implant clinical parameters (modified plaque index (mPI), bleeding and/or suppuration on probing (B/SOP))...  相似文献   
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Calcifying cystic odontogenic tumors (CCOTs) are benign cystic lesions of odontogenic origin characterized by an ameloblastoma-like epithelium and the presence of a group of cells named ghost cells. The pattern of cytokeratin (Ck) expression on these lesions remains unclear and needs to be clarified. To this end, the expression of Ck6, Ck13, Ck14, Ck18, and Ck19 in the epithelium lining of 7 cases of CCOTs was evaluated by immunohistochemistry. For this, the epithelium lining was divided into 3 distinct regions: basal layer, suprabasal layer, and the compartment composed of ghost cells. In this study, 6 cases (85.7%) were classified as type 1 and 1 (14.3%) as type 4. All cases were negative for Ck13 and Ck18, despite the epithelial layer, as well as in the ghost cells. Ck6 was only positive in the ghost cells. Positivity for Ck14 and Ck19 was found in the basal and suprabasal layers, including the ghost cells. The results showing positivity for Ck14 and Ck19 in all of the analyzed cases reinforce CCOT as being of odontogenic origin, and the restricted expression of Ck6 in the ghost cells may be indicative that these cells suffer an altered differentiation into hair follicles in CCOTs.  相似文献   
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The interest in non-invasive brain stimulation techniques is increasing in recent years. Among these techniques, transcranial direct current stimulation (tDCS) has been the subject of great interest among researchers because of its easiness to use, low cost, benign profile of side effects and encouraging results of research in the field. This interest has generated several studies and randomized clinical trials, particularly in psychiatry. In this review, we provide a summary of the development of the technique and its mechanism of action as well as a review of the methodological aspects of randomized clinical trials in psychiatry, including studies in affective disorders, schizophrenia, obsessive compulsive disorder, child psychiatry and substance use disorder. Finally, we provide an overview of tDCS use in cognitive enhancement as well as a discussion regarding its clinical use and regulatory and ethical issues. Although many promising results regarding tDCS efficacy were described, the total number of studies is still low, highlighting the need of further studies aiming to replicate these findings in larger samples as to provide a definite picture regarding tDCS efficacy in psychiatry.  相似文献   
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