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41.
The toothbrush is a fundamental tool used for accomplishing plaque control. Various types of toothbrushes available in the market keep the buyer in a state of dilemma as to which one to choose, due to lack of information about the "quality" of it. This study has been designed to understand whether all the products available in the market adhere to the specifications laid down by the ADA, which is universally accepted in standardization of a tooth brush. 95% of the brushes surveyed contain less number of bristles per tuft than specified and a large percentage deviate from the standard prescribed value for their bristle diameter and other dimensions. Few brushes labeled as "Soft" were "Medium" and labeled "Medium" were "Hard". The study will bring to light the quality of toothbrushes available in India for a rationalised selection of appropriate toothbrush by the community at large.  相似文献   
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The authors present an interesting case of a 60-year-old man who underwent right hepatectomy for a diagnosis of hepatocellular carcinoma (HCC) on a background of noncirrhotic chronic hepatitis C. Pathologic examination confirmed the presence of HCC near the porta hepatis, which invaded the right portal vein branch. In addition, a well-demarcated 13.5 × 7.8 × 4.0 cm yellow and firm area upstream of the HCC was noted. This yellow area corresponded to a tumoral ductular proliferation, which cytologically was extremely bland, but invaded portal tracts and the adjacent liver parenchyma. This tumoral proliferation mimicked ductular reaction, except that it had more anastomosing structures and was associated with abundant hyalinized fibrotic stroma. Cytologically, the tumor cells had round to oval nuclei with fine chromatin, indistinct nucleoli, and scant cytoplasm. They exhibited immunohistochemical features of hepatic progenitor cells, i.e., expressing CK7, CK19, and N-CAM; and their malignancy was supported by the p53 and Ki67 immunoreactivity. The authors concluded that the patient had cholangiolocellular carcinoma with an aggressive hepatocellular carcinoma component. Cholangiolocellular carcinoma has been reported to be associated with chronic hepatitis C viral infection and to derive from hepatic progenitor cells, which explains why hepatocellular carcinoma and/or cholangiocarcinoma component may be present.  相似文献   
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β-Thalassemia (β-thal) is the most frequently observed hereditary blood disorder that results from genetic defects causing deficient synthesis of hemoglobin (Hb) polypeptide chains. Detecting thalassemia mutations are necessary for prenatal diagnosis (PND) programs leading a better quality of life for the patients, as well as a reduction in the cost of their medical care. There are more than 900 different genomic mutations of the β-globin gene described in the human hemoglobin variant (HbVar) database. In this study, we identified a mid-intronic mutation at IVS-II-821 (A>C) (HBB: c.316-30A>C) position in the HBB gene of an Iranian proband and two of her siblings that was associated with β-thal clinical features. Direct DNA sequence analysis was performed by mutation scanning of the β-globin gene. Based on the observed β-thal phenotype and bioinformatics analysis results, we concluded that this β-globin gene mutation was associated with a mild phenotype of β-thal through activating potential splice sites by creating exonic splicing enhancers (ESEs), exon-identity element (EIE) and exonic splicing regulatory sequences (ESRs) sites.  相似文献   
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Supernumerary marker chromosomes (SMCs) are frequently found at pre- and postnatal cytogenetic diagnosis and require identification. A disproportionally large subset of SMCs is derived from the human chromosome 22 and confers tri- or tetrasomy for the cat eye chromosomal region (CECR, the proximal 2 Mb of chromosome 22q) and/or other segments of 22q. Using fluorescence in situ hybridization (FISH) and 15 different DNA probes, we studied nine unrelated patients with an SMC(22) that contained the CECR. Five patients showed the small (type I) cat eye syndrome (CES) chromosome and each one had the larger (type II) CES chromosome, small ring chromosome 22, der(22)t(11;22) extrachromosome, and a novel type of bisatellited SMC(22) with breakpoints outside the low-copy repeats (LCRs22). By size and morphology, the novel bisatellited SMC(22) resembled the typical (types I and II) CES chromosomes, but it might have been associated with the chromosome 22q duplication syndrome, not CES. This SMC included a marker from band 22q12.3 and conferred only one extra copy each of the 22 centromere, CECR, and common 22q11 deletion area. There has been no previous report of a bisatellited SMC(22) predicting the chromosome 22q duplication syndrome. Accounting for the cytogenetic resemblance to CES chromosomes but different makeup and prognosis, we propose naming this an atypical (type III) CES chromosome. In this study, we found six distinct intervals on 22q to be relevant for FISH diagnostics. We propose to characterize SMCs(22) using DNA probes corresponding to these intervals.  相似文献   
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Tumor necrosis factor receptor-associated periodic syndrome (TRAPS) is a periodic fever syndrome inherited in an autosomal dominant fashion. It stems from mutations in the TNFRSF1A (accession number: NM_001065) gene expressing the receptor for tumor necrosis factor α. A patient with TRAPS may present with prolonged episodes of fever attacks, abdominal pain, severe myalgia, and painful erythema on the trunk or extremities. Here, we report an 8-year-old boy with febrile attacks occurring every 1–2 months and continuing for 3–4 days. The patient experienced 40 °C-fever attacks without chills. Approximately 80% of fever attacks were accompanied by abdominal manifestations. Direct sequencing analysis was used to assess the genomic DNA of the patient, and a heterozygous R426L mutation in exon 10 of the TNFRSF1A gene in an autosomal dominant inheritance fashion was identified. Further genetic analyses were also carried out on his parents. Due to the fact that the mutation was not inherited from the parents, it was likely that R426L was a de novo and novel mutation in the TNFRSF1A gene, which can trigger TRAPS or TRAPS-like symptoms.  相似文献   
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A molecular and serological study was carried out to determine the West Nile virus (WNV) status in different species of wild water birds. From 2003 to 2007, samples were collected from 519 birds representing 26 different species in Iran. Out of 519 serum samples tested for WNV antibodies, 78 (15%) were positive when tested using virus neutralization and immunofluorescence. Antibodies of WNV were detected in 71 out of 131 common coot (Fulica atra) samples. In comparison, only 7 out of 388 birds that were belonged to 25 other species of water birds revealed positive results. For most Anatidae species, no positive duck in serological tests was found. Further, no WNV viral RNA-positive samples were found in this study. Results of this investigation provide important information about the prevalence of WNV in wild water birds in Iran and indicate the potential role and importance of common coots in ecology of WNVs.  相似文献   
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