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991.
Desmoplastic Ameloblastoma is a rare variant of ameloblastoma. 90 cases of desmoplastic ameloblastoma have been reported so far in literature. We are presenting a rare case of desmoplastic ameloblastoma in the ramus region of mandible with regards to its clinical and radiographical viewpoints. Only one other case of desmoplastic ameloblastoma has been reported in the ramus region of mandible of the 90 cases that we have reviewed. Review of literature has revealed the tumour to most commonly occur in the 3rd to 5th decade of life with a high preponderance of Japanese males. The anterior region of either jaw was most commonly found to be affected. Radiological appearance was most commonly of a mixed radio-lucent/radio-opaque type with a high incidence of poorly defined borders. However our case differed from the reviewed cases as it was found to be a unilocular lesion with well defined borders. Histopathological findings of our case were consistent with the hisotpathological appearance of the reviewed cases and showed extensive stromal desmoplasia and small tumour nests of odontogenic epithelium scattered in stroma.  相似文献   
992.
When demand for cholesterol rises in mammalian cells, the sterol regulatory element (SRE) binding proteins (SREBPs) are released from their membrane anchor through proteolysis. Then, the N-terminal region enters the nucleus and activates genes of cholesterol uptake and biosynthesis. Basic helix–loop–helix (bHLH) proteins such as SREBPs bind to a palindromic DNA sequence called the E-box (5′-CANNTG-3′). However, SREBPs are special because they also bind direct repeat elements called SREs. Importantly, sterol regulation of all promoters studied thus far is mediated by SREBP binding only to SREs. To study the reason for this we converted the direct repeat SRE from the sterol-regulated low-density lipoprotein receptor promoter into an E-box. In this report we show that SREBPs are still able to bind and activate this promoter however, sterol regulation is lost. The results are consistent with the mutant promoter being a target for promiscuous activation by constitutively expressed E-box binding bHLH proteins that are not regulated by cholesterol. Kim and coworkers [Kim, J. B., Spotts, G. D., Halvorsen, Y.-D., Shih, H.-M., Ellenberger, T., Towle, H. C. & Spiegelman, B. M. (1995) Mol. Cell. Biol. 15, 2582–2588] demonstrated that the dual DNA binding specificity of SREBPs is caused by a specific tyrosine in the conserved basic region of the DNA binding domain that corresponds to an arginine in all other bHLH proteins that recognize only E-boxes. Taken together the data suggest an evolutionary mechanism where a DNA binding protein along with its recognition site have coevolved to ensure maximal specificity and sensitivity in a crucial nutritional regulatory response.  相似文献   
993.
994.
995.
Meckel's diverticulum represents a patent omphalomesenteric duct at its junction with the ileum. Although it is a common anomaly, it is often a surgical surprise as the preoperative diagnosis is seldom established. We present an unusual case where the constellation of imaging findings was so typical that we could suggest this diagnosis prospectively and it was subsequently confirmed surgically.  相似文献   
996.
Summary: Purpose : Large numbers of families with many members having seizures have been used to understand the role of hereditary factors in the pathogenesis of human epileptic syndromes. We aimed to establish a genetic database to form a hypothesis on the possible genetic contributions in different epileptic syndromes.
Methods : The occurrence and patterns of different epilepsies and epileptic syndromes in 1,219 Indian probands and their relatives were studied. The concordance of epilepsies between probands and relatives was also analyzed.
Results : Of probands, 231 (19% of 1219) had first– or second- degree relatives affected with seizures. Incidence of family history in probands with generalized epilepsies (GES) and syndrome of single, small, enhancing lesions (SSEL) was comparable and significantly higher than that in probands with localization-related epilepsies (LRES). The ratio of affected first- to second-degree relatives was close to 4:1. Generalized epilepsies were the commonest type of epileptic syndromes seen among all relatives. The proportion of sibs and second-degree relatives with epileptic syndromes similar to probands was significantly greater in the GES group as compared with the concordant relatives of probands with LRES and SSEL.
Conclusions : A significant percentage of first- and second–degree relatives of probands with all types of epileptic syndromes have seizures. The risk of relatives being affected varied as a function of the relation with the proband. Concordance of epileptic syndromes between probands and relatives was related to the epileptic syndromes in probands. The syndrome of SSEL is probably a benign epileptic syndrome seen in Indians genetically predisposed to seizures. Hereditary factors may play an almost equal role in the predisposition of relatives to epilepsy in families of probands with different epileptic syndromes.  相似文献   
997.
998.
Background and Objectives: Twenty five to 30% of multiple-transfusion recipients in India show evidence of infection with both HBV and non-A non-B hepatitis or HCV. To be licensed, blood banks must screen each donor unit for HBsAg, antibodies to HIV-1 and -2, and VDRL. Materials and Methods: Between 1989 and 1996, 132,093 voluntary and replacement donors at this centre were screened for the above markers, using commercially available kits. Some 19,531 donors were screened for HCV antibodies in 1995 and 1996 with an inhouse EIA, using a synthetic peptide from core, NS3 and NS4 region proteins of all major HCV strains. Results: Data were tabulated annually. The proportion of voluntary donors increased from 15 to 32% during the eight years. HBsAg rates remained below 2.5%, antibodies to HIV increased from 0.04% to 0.55%, and VDRL reactivity increased from 0.23 to 0.52% between 1989 and 1995. Prevalence of all three infections showed a small but significant drop in 1996, and all three were significantly less frequent in voluntary donors. HCV antibodies were detected in 1.49% of donors tested. Donors with multiple infections were uncommon. Conclusions: A change to voluntary blood transfusion service and addition of anti-HBc, anti-HCV, and possibly HIV antigen to the mandatory list for screening donor blood would reduce posttransfusion infections. Indigenous production of these assays would mitigate the financial burden, as has been the experience with the in-house HCV assay.  相似文献   
999.
Purpose  Acute liver failure (ALF) is characterized by a rapid and massive destruction of hepatocytes. The role of oxidative stress in perpetuating the injury is undefined and may be a potential therapeutic target. Our aim was to study serial variation in oxidative stress and antioxidant status in patients with ALF. Methods  The study involved a prospective case–control study set in a tertiary care referral center. Thirty-two consecutive patients admitted with ALF were included with 23 healthy controls for comparison. Level of systemic oxidative stress as defined by superoxide dismutase (SOD), lipid peroxidation products (thiobarbituric acid reactive derivatives [TBARS]), and the total antioxidant capacity as the ferric reducing ability of plasma (FRAP) was measured at baseline on days 3 and 7. Results  The patients were aged 24 years (range 13–60 years) and included 20 females. Thirteen (40.6%) patients died. Patients with ALF had significantly increased systemic oxidative stress at presentation, as reflected by higher levels of SOD (P < 0.001) and TBARS (P < 0.001) than controls. Both TBARS levels and FRAP decreased progressively from admission to the end of first week among the survivors (P = 0.004 and 0.015, respectively). The antioxidant status reflected by FRAP (P = 0.001) was significantly lower in ALF patients than controls. No relation was found between the level of oxidative stress and the mortality or complications. Conclusion  A high level of systemic oxidative stress exists in ALF, with depletion of antioxidant reserves. Further studies are needed to define the clinical correlation of the large pro-oxidant burden.  相似文献   
1000.
Imaging alone cannot differentiate various isolated atypical lytic lesions involving the skull. Clinical and radiological correlation is mandatory in reaching to a diagnosis. Histopathology remains the gold standard. We describe few atypical cases presenting as isolated lytic lesions of skull with characteristic imaging findings and a brief clinical approach to reach towards the diagnosis.  相似文献   
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