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Liver cysts in the newborn often pose significant diagnostic challenges. Described herein is a case of large congenital liver cyst that was difficult to diagnose both antenatally and postnatally and which was later diagnosed as Caroli disease. 相似文献
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M. Viswanathan M.I. McCarthy C. Snehalatha G.A. Hitman A. Ramachandran 《Diabetic medicine》1996,13(3):232-237
The family histories of 976 South Indian Type 2 diabetic patients were recorded in a questionnaire-based survey to establish whether the excess maternal transmission of Type 2 diabetes reported in low prevalence Europid populations was also evident in this medium prevalence population. In 450 families (46.1 %), no parental history of diabetes was reported. In 423 families with one parent diabetic, 222 fathers (52.5 %) and 201 (47.5 %) mothers were diabetic. In the remaining 103 (10.6 %) families, both parents were diabetic. In contrast to previous studies, we found no evidence for substantial maternal excess in the transmission of diabetes (325 diabetic fathers vs 304 mothers; p = 0.4; p = 0.07 when compared using life table methods). The age of diagnosis of diabetes in probands was lower than that of their diabetic parents (p < 0.001): furthermore increasing parental history of diabetes was associated with an earlier diagnosis of diabetes in probands (p < 0.001). These results emphasize the extensive familial aggregation of Type 2 diabetes in this population but fail to replicate the evidence for excess maternal transmission evident in lower prevalence Europid populations, suggesting ethnic differences in the extent of this phenomenon. 相似文献
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M. McCarthy P. Cassell T. Tran L. Mathias L.M. 't Hart J.A Maassen C. Snehalatha A. Ramachandran M. Viswanathan G.A. Hitman 《Diabetic medicine》1996,13(5):420-428
In 79 South Indian nuclear pedigrees ascertained via probands with NIDDM and both parents living, parental diabetic status was established through previously diagnosed NIDDM (n = 97) or oral glucose tolerance testing (n = 61). There was no significant difference between diabetes prevalence in mothers and fathers (60 vs 53 (76 % vs 67 %), respectively, p = 0.22). ‘Age at diabetes diagnosis’ survival curves did differ according to parental gender (p = 0.02) but this may reflect gender differences in health provision rather than pathophysiology. No maternal excess effects of the magnitude evident in previous studies were detected, suggesting either ethnic differences or overestimation of the maternal effect when reported histories of parental diabetes have been used. The tRNALeu(UUR) gene region was studied for diabetes-associated variation given the role of mutations in this gene in some pedigrees displaying maternal transmission of NIDDM. None of 142 unrelated South Indian NIDDM subjects displayed the MELAS mutation at nt3243. However, sequencing identified two variants of potential importance: (a) at nt3290 in the tRNALeu(UUR) gene, seen in 7/142 diabetic and 1/85 control subjects (p = 0.11), (b) at nt3316 in the ND1 gene (4/142 vs 1/85 subjects, respectively (p = 0.51)). Further studies are needed to determine the relevance of these variants to the development of NIDDM. 相似文献
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Ricardo Chvez-Vsconez Sheila Lascano Sergio Sauceda Mauricio Reyes-Valenzuela Christopher Salvo Ramalinga Viswanathan Mangalaraja Francisco Jos Gotor Cristina Arvalo Yadir Torres 《Materials》2022,15(1)
Commercially pure (c.p.) titanium grade IV with a bimodal microstructure is a promising material for biomedical implants. The influence of the processing parameters on the physical, microstructural, and mechanical properties was investigated. The bimodal microstructure was achieved from the blends of powder particles with different sizes, while the porous structure was obtained using the space-holder technique (50 vol.% of ammonium bicarbonate). Mechanically milled powders (10 and 20 h) were mixed in 50 wt.% or 75 wt.% with c.p. titanium. Four different mixtures of powders were precompacted via uniaxial cold pressing at 400 MPa. Then, the specimens were sintered at 750 °C via hot pressing in an argon gas atmosphere. The presence of a bimodal microstructure, comprised of small-grain regions separated by coarse-grain ones, was confirmed by optical and scanning electron microscopies. The samples with a bimodal microstructure exhibited an increase in the porosity compared with the commercially available pure Ti. In addition, the hardness was increased while the Young’s modulus was decreased in the specimens with 75 wt.% of the milled powders (20 h). 相似文献
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