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81.
Iron is an indispensable element for vital activities in almost all living organisms. It is also a cofactor for many proteins, enzymes, and other essential complex biochemical processes. Therefore, iron trafficking is firmly regulated by Hepcidin (Hamp), which is regarded as the marker for iron accumulation. The disruption of iron homeostasis leads to oxidative stress that causes various human diseases, but this mechanism is still unclear. The aim of this study is to provide a better in vivo and in vitro understanding of how long‐term iron overload affects the gene expression and activities of some antioxidant enzymes, such as glucose 6‐phosphate dehydrogenase (G6PD), 6‐phosphogluconate dehydrogenase (6PGD), and glutathione reductase (GR) in the spleen. The findings of this study show that iron overload reduces the gene expression of G6pd, 6pgd, and Gr, but its actual effect was on the protein level.  相似文献   
82.
Endosulfan, a chlorinated hydrocarbon insecticide of cyclodiene subgroup acts as a contact poison in a wide variety of organisms. In the present study, the effect of endosulfan on the growth, alpha amylase activity and plasmid amplification was investigated in Bacillus subtilis system. The bacteria were grown in medium, incubated with different concentrations (32, 48, 64 and 80 microg/mL) of endosulfan. The bacterial growth was gradually seen after 1st day at up to 48 microg/L endosulfan. The 48 microg/L endosulfan inhibited approximately 50% of the bacterial growth. No growth was observed at and after 64 microg/L endosulfan, for all days (1-5). Also, no alpha amylase activity was found in the supernatant of the culture medium containing 64 and 80 microg/L endosulfan, whereas slight activity was observed with 32 and 48 microg/L endosulfan concentration. The amount of plasmid increased up to 50% in the presence of 32 microg/L endosulfan. Endosulfan had no effect on the alpha amylase activity in vitro.  相似文献   
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84.
Substituted polyaniline/chitosan(PANIs/Ch) composites were chemically synthesized by using ammonium peroxydisulfate as oxidant and characterized by measurements of conductivity, FTIR, UV–vis, SEM and TGA techniques. FTIR spectra of the composites revealed that there is a strong interaction between substituted polyanilines and chitosan. Among the substituted polyaniline/chitosan composites synthesized, poly(N-ethylaniline)/chitosan PNEANI/Ch has the highest conductivity with a value of 1.68 × 10?4 S/cm. The P2EANI/Ch composite exhibited higher thermal stability than the other composites. SEM images of the composites showed an agglomerated granular morphology of substituted polyaniline particles coated on the surface of chitosan.  相似文献   
85.
Cadherins, being responsible for selective cell recognition and normal tissue integrity in adults, regulate morphogenesis in a variety of organs during development. In this study, anti-rat pan-cadherin antibody, specific to all subgroups of the cadherin family, was used to map the distribution of the pan-cadherin immunoreactivity in adult rat organs. Pan-cadherin immunoreactivity positive tissues were: secretory cells of the adenohypophysis, autonomic nerve, corneal epithelium, oesophageal nerve plexus, stomach and pyloric glandular cells, epithelium of the ileum and its nerve plexus, alveolar cells of the lung, proximal convoluted tubules of the kidney, islet cells of Langerhans, and the acinar cells of the exocrine pancreas. For the first time, positive pan-cadherin immunoreactivity was demonstrated in the epithelial cells of the corpus ciliaris and in the nerve plexus of corpus cavernosum of the penis. In conclusion, our results suggest that cells in many tissues and organs of the adult rat synthesize cadherins.  相似文献   
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87.
The Mersin Mélange, a sedimentary complex in southern Turkey, includes blocks of various origins within a Late Cretaceous matrix. Two blocks in the Mersin Mélange are herein recognized to be of Carboniferous age. One block (the Kozan Block) is composed of alternating chert and mudstone, and includes radiolarian and conodont assemblages revealing a late Tournaisian (Early Mississippian) age. The other (Keven-West Block) consists of platform carbonate containing abundant foraminifera indicating Bashkirian (Early Pennsylvanian) age. These dates are so far the oldest obtained from the blocks within the Mersin Mélange. A correlation of the lithostratigraphies of blocks in the Mersin Mélange with the coeval Tauride sequences indicates that they correspond to the successions in the Beysehir-Hoyran Nappes. In these nappes, the late Tournaisian is characterized by radiolarian rich chert and mudstone of an open marine environment, whereas the Bashkirian succession represents a shallow water environment with Foraminifera-bearing limestone. The Tournaisian deepening can be ascribed to the opening of a deep marginal basin to the north of the Tauride Platform and uplifting of the northern Tauride-Anatolide Platform margin during the Late Mississippian and Early Pennsylvanian.A shallowing upward sequence started in the Tournaisian with a pelagic sequence followed by platform carbonates of Bashkirian age in the Beysehir-Hoyran Nappes, and could be related to a major glaciation event during late Visean–Serpukhovian resulting in a sea-level drop and deposition of platform carbonates in the Bashkirian. Given the stratigraphic properties of northerly originated nappe packages (Cataloturan, Hadim and Bolkardag) and parautochthonous/autochthonous sequences in Taurides, sedimentation on the Tauride-Anatolide Platform mainly terminated after the Moscovian, except in the Hadim Nappe with sedimentation in a very shallow sea conditions until the end of the Permian. A depositional break corresponding to the Kasimovian–Wordian time interval in these sequences in the Tauride-Anatolide Platform could be related to the effects of both late Paleozoic Gondwanan glaciation and a possible mantle plume occurrence evidenced by the geochemistry of lavas in the Mersin Mélange causing major uplift in the Northern NeoTehys Ocean. However; at the center of the plume, pelagic sequences (e.g., ribbon chert and pelagic limestone) were deposited associated with these lavas due to a progressive developing rift system during the Permian, based on previous studies.  相似文献   
88.
The purpose of this study was to investigate prospectively the effects of swaddling and consanguineous marriage on developmental dysplasia of the hip and associated risk factors. We screened by ultrasound 265 infants using the Graf method. The Pediatrics Department referred all newborn infants with suspected instability or a recognized risk factor to the orthopedic clinic. Risk factors of developmental dysplasia of the hip were searched and noted in these patients. Swaddling and consanguineous marriage were also determined and noted. We observed 164 of 265 infants (61.9 %) who had been swaddled and that 64 of 265 infants’ parents were in a consanguineous marriage (24.2 %). In the statistical analysis that was conducted for swaddling and consanguineous marriage, highly significant differences were found. Our study showed that the rate of developmental dysplasia of the hip is very high, 11.7 %, in our region, eastern Turkey. Also, we commonly see improper swaddling and consanguineous marriage in our region, which affects many infants.  相似文献   
89.
Prospects for facial allograft transplantation in humans   总被引:4,自引:0,他引:4  
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90.
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