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1.
Iron is an essential element for diverse biological functions. In mammals, the majority of iron is enclosed within a single prosthetic group: heme. In metazoans, heme is synthesized via a highly conserved and coordinated pathway within the mitochondria. However, iron is acquired from the environment and subsequently assimilated into various cellular pathways, including heme synthesis. Both iron and heme are toxic but essential cofactors. How is iron transported from the extracellular milieu to the mitochondria? How are heme and heme intermediates coordinated with iron transport? Although recent studies have answered some questions, several pieces of this intriguing puzzle remain unsolved.  相似文献   
2.
ABO, Rh and MN blood groups were studied among the people of Ahwaz, Khuzistan, Iran. The people of Ahwaz are characterized by high frequencies of the blood groups 0 (41.16%), Rh-positive (90.0%) and MN (48.13%). These frequencies are significantly different from those obtained in other Iranian populations, which is caused by the co-operation of various factors.  相似文献   
3.
234 218 births (1975-1983) from a hospital in Tehran have been analysed for seasonality of birth and sex ratio. The results show more births in winter and less births in fall. The sex ratio is higher in summer and lower in fall. The occurrence of multibirths shows higher twinning and triplet rates in spring and fall, respectively, whereas lower twinning and triplet rates occur in winter and summer, respectively. It could be demonstrated that geographical factors influence the rates of births and multibirths as well as the sex ratio.  相似文献   
4.
We analyzed bilateral finger prints of 3158 individuals from 13 Iranian populations of diverse origins, for digital patterns, using the topological method. Some male/female differences, and a great deal of heterogeneity in interpopulational variation was observed. Distance analysis, and the resultant dendrograms separated the populations studied, but the separation was not in agreement with the known ethnohistory of this region. Comparison of the obtained results with those based on the traditional methodology showed that the traditional methodology gives better results in measuring population distances.  相似文献   
5.
Summary X-ray structure determinations of HBTU and HATU, well-known reagents for peptide bond formation, show that the solid-state structures of these compounds differ markedly from those commonly presented in the literature. The solid-state structures are isomers of the N,N,N',N'-tetramethyluronium salt formulation commonly written for HBTU and HATU. HBTU and HATU, obtained either directly from synthesis or from CH3CN solution, crystallize as the guanidinium N-oxide isomers. Both compounds crystallize in nearly identical conformations, despite marked differences in crystal packing.  相似文献   
6.
Angiogenesis is a vital step in tissue regeneration. Hence, the current study aimed to prepare oxidized dextran (Odex)/collagen (Col)-hydrogels with laminin (LMN), as an angiogenic extracellular matrix (ECM) component, for promoting human umbilical vein endothelial cell (HUVEC) proliferation and function. Odex/Col scaffolds were constructed at various concentrations and temperatures. Using oscillatory rheometry, scanning electron microscopy (SEM), and cell viability testing, the scaffolds were characterized, and then HUVEC proliferation and function was compared with or without LMN. The gelation time could be modified by altering the Odex/Col mass ratio as well as the temperature. SEM showed that Odex/Col hydrogels had a more regular three-dimensional (3D) porous structure than the Col hydrogels. Moreover, HUVECs grew faster in the Col scaffold (12 mg/mL), whereas the Odex (30 mg/mL)/Col (6 mg/mL) scaffold exhibited the lowest apoptosis index. Furthermore, the expression level of vascular endothelial growth factor (VEGF) mRNA in the group without LMN was higher than that with LMN, and the Odex (30 mg/mL)/Col (6 mg/mL) scaffold without LMN had the highest VEGF protein secretion, allowing the cells to survive and function effectively. Odex/Col scaffolds, with or without LMN, are proposed as a tissue engineering construct to improve HUVEC survival and function for angiogenesis.  相似文献   
7.
Aluminum was determined in serum samples obtained from 533 Saudi female pupils aged 6–8 years who attended primary public school in Riyadh City, Capital of Saudi Arabia. The aluminum mean value was 23.21 ± 15.25 g 1–1 in the range of 5.98–206.93 g 1–1. Serum aluminum levels of pupils attending the Northern school area were higher than levels found in pupils from other school areas (Southern, Eastern and Central). Renal variables had no correlation with serum aluminum. On the other hand, a significant positive correlation was found between serum aluminium above 49.2 g 1–1 and urea (r = 0.6, P < 0.002). Although 53% of the screened schools had aluminum in water above the European Union (EU) acceptable limit of 50 g 1–1, there were no differences in aluminum in water between the four different school areas in Riyadh. Factors such as drinking water, diet and the use of aluminum utensils may have contributed to this result. As there is a bulk of literature which highlights the adverse developmental effects of aluminum on children and infants, it would be advantageous to establish regular aluminum monitoring.  相似文献   
8.
The influence of application of skin-lightening creams and dental amalgam fillings on the urinary mercury (Hg) level was evaluated in 225 females (ages 17 to 58 years) living in Riyadh, capital of Saudi Arabia. The arithmetic mean of the urinary Hg level was 6.96 ± 20.43 g l, in the range 0 to 204.8 g l. The mean urinary Hg level adjusted by creatinine (Cr) was 11.22 ± 37.23 g g Cr, in the range 0 to 459.37 g g. No significant difference in urinary Hg was noted between the females regarding the use of skin-lightening creams. On the other hand, results showed that urinary Hg concentration was influenced by the use and number of dental amalgam fillings. No women were identified with symptoms or signs that could be attributed to Hg intoxication. Urine analyses for creatinine, urea, uric acid, phosphorus, magnesium, glucose and calcium showed significant correlation with urinary Hg. This suggests that chronic exposure to Hg may be associated with a deterioration of renal function.  相似文献   
9.
The bilateral palmar prints of 3,158 females and males from 13 Iranian populations of diverse origins were analyzed to see how well topological palmar pattern frequencies reflect population distances. The results showed bimanual variation among most of the populations studied. Sex variation showed significant differences among all of the populations studied. Distance analysis and constructed dendrograms showed separation between the populations studied. These distances were frequently in agreement with the known ethnohistoric background of the populations studied. The male data gave better results. It appears that topological palmar patterns are a better indicator of population distance than topological finger patterns.  相似文献   
10.
Progressive familial intrahepatic cholestasis is an autosomal recessive liver disorder caused by (biallelic) mutations in the ATP8B1 of ABCB11 gene. A nine-year-old girl with cholestasis was referred for genetic counseling. She had a family history of cholestasis in two previous expired siblings. Genetic analysis of the ABCB11 gene led to the identification of a novel homozygous mutation in exon 25. The mutation 3593- A > G lead to a missense mutation at the amino acid level (His1198Arg). This mutation caused PFIC2 due to abnormal function in the bile salt export pump protein (BSEP).  相似文献   
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