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1.
Pancreases from three male and three female echidnas ( Tachyglossus aculeatus ), possums ( Trichosurus vulpecula ), grey kangaroos ( Macropus fuliginosus ), spinifex hopping mice ( Notomys alexis ) and water rats ( Hydromys chrysogaster ) were studied using a point-intercept method and Weibel graticule (Weibel, Kistler & Scherle, 1966) on sections stained by an immunoperoxidase method for pancreatic polypeptide (PP). PP cells were assessed in the head, neck, body and tail regions. There was a greater percentage proportion of PP cells in the head than in the other regions of echidna, possum and water rat. PP cells were not identified in grey kangaroo and spinifex hopping mouse, although control sections were positive.
These results show some agreement with a previously proposed hypothesis (Bonner-Weir & Weir, 1979) concerning the distribution of cell types in the mammalian endocrine pancreas. 相似文献
These results show some agreement with a previously proposed hypothesis (Bonner-Weir & Weir, 1979) concerning the distribution of cell types in the mammalian endocrine pancreas. 相似文献
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Highly enhanced adsorption for decontamination of lead ions from battery wastewaters using chitosan functionalized with xanthate 总被引:3,自引:0,他引:3
Decontamination of lead ions from aqueous media has been investigated using cross linked xanthated chitosan (CMC) as an adsorbent. Various physico-chemical parameters such as contact time, amount of adsorbent, concentration of adsorbate were optimized to simulate the best conditions which can be used to decontaminate lead from aqueous media using CMC as an adsorbent. The atomic absorption spectrometric technique was used to determine the distribution of lead. Maximum adsorption was observed at both pH 4 and 5. The adsorption data followed both Freundlich and Langmuir isotherms. Langmuir isotherm gave a saturated capacity of 322.6+/-1.2mg/g at pH 4. From the FTIR spectra analysis, it was concluded that xanthate and amino group participate in the adsorption process. The developed procedure was successfully applied for the removal of lead ions from real battery wastewater samples. 相似文献
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The present study showed that exposure of chlorpyrifos, O,O'-diethyl-O-3,5,6-trichloro-2-pyridyl phosphorothionate (CPF), a widely used pesticide in rats caused significant inhibition of acetylcholinesterase (AChE) activity in different tissues viz., liver, kidney and spleen. CPF exposure also generated oxidative stress in the body, as evidenced by increase in thiobarbituric acid reactive substances (TBARS), decrease in the levels of superoxide scavenging enzymes viz., superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) in liver, kidney and spleen at all doses. Malondialdehyde levels were increased by 14%, 31% and 76% in liver, 11%, 31% and 64% in kidney and 32%, 75% and 99.9% in spleen when 50 mg, 100 mg and 200 mg/kg body wt. CPF was administered for three days. SOD and CAT activities were decreased in liver, kidney and spleen, while GPx activity showed slight increase in kidney at 50 mg and 100 mg dose, and decreased on further increase in dose of CPF. Liver and spleen showed dose-dependent decrease in GPx activity. The levels of reduced glutathione (GSH) was decreased, while oxidized glutathione (GSSG) was increased, thus a marked fall in GSH/GSSG ratio was observed in all tissues. A maximum decrease of 83% was observed in liver, followed by kidney and spleen, which showed 78% and 57% decrease, respectively in group given 200 mg/kg CPF. The levels of glucose-6-phosphate dehydrogenase (G6PDH) and glutathione reductase (GR) were also decreased in liver and kidney, while spleen showed increase at lower doses, but decrease at high dose of CPF. The data provide evidence for induction of oxidative stress on CPF exposure. 相似文献
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Abstract Random Amplified Polymorphic DNA polymerase chain reaction (RAPD‐PCR) is a fast and easy way of identifying DNA polymorphisms generated from several regions of the genome. This could expedite the process of identifying informative polymorphic markers that may be linked to important genes controlling economic traits. In cattle, failure to obtain consistent amplification patterns in RAPD‐PCR has been a cause for concern. This has been attributed to the fact that decamer primers that are used in RAPD‐PCR reactions are likely to amplify regions of DNA where the primer‐template base pairing has some degree of mismatch and that these mismatches fail to repeat from reaction to reaction. This paper describes the use of tricine buffer along with changes in reaction components and thermal cycling conditions that has yielded consistent and reproducible RAPD‐PCR amplifications using single primers and double primer combinations on bovine DNA. 相似文献
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Nalini Santanam MingQing Song Rong Rong Ana A. Murphy Sampath Parthasarathy 《Free radical research》2013,47(12):1315-1321
Endometriosis affects younger women of childbearing age. Atherosclerosis is considered as a disease of the old and increases with the ageing process. Both diseases are characterized by the increased presence of activated macrophages and associated increases in growth promoting activity and the production of inflammatory cytokines. In this review, we propose that oxidative stress and the presence of forms of oxidized low-density lipoprotein (LDL) might contribute to both Atherosclerosis and Endometriosis. 相似文献
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Background
Perturbations in abdominal fat secreted adipokines play a key role in metabolic syndrome. This process is further altered during the aging process, probably due to alterations in the preadipocytes (aka. stromal vascular fraction cells-SVF cells or adipose derived stem cells-ASCs) composition and/or function. Since microRNAs regulate genes involved both in development and aging processes, we hypothesized that the impaired adipose function with aging is due to altered microRNA regulation of adipogenic pathways in SVF cells.Methodology and Principal Findings
Alterations in mRNA and proteins associated with adipogenic differentiation (ERK5 and PPARg) but not osteogenic (RUNX2) pathways were observed in SVF cells isolated from visceral adipose tissue with aging (6 to 30 mo) in female Fischer 344 x Brown Norway Hybrid (FBN) rats. The impaired differentiation capacity with aging correlated with altered levels of miRNAs involved in adipocyte differentiation (miRNA-143) and osteogenic pathways (miRNA-204). Gain and loss of function studies using premir or antagomir-143 validated the age associated adipocyte dysfunction.Conclusions and Significance
Our studies for the first time indicate a role for miRNA mediated regulation of SVF cells with aging. This discovery is important in the light of the findings that dysfunctional adipose derived stem cells contribute to age related chronic diseases. 相似文献9.
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Bioleaching is a technology applicable to metal extraction from low-grade ores, ore beneficiation, coal beneficiation, metal detoxification, and recovery of metals from waste materials. The technology is environmentally sound and it may lower operational cost and energy requirement. Whereas leaching of sulfidic minerals using chemolithoautotrophic bacteria is the most studied and commercially exploitable aspect of mineral biotechnology today, there is a dearth of literature on the dissolution of nonsulfidic minerals. Biohydrometallurgy of nonsulfidic minerals involves the action of heterotrophic microorganisms. Heterotrophic bacteria and fungi have the potential for producing acidic metabolites that are able to solubilize oxide, silicate, carbonate and hydroxide minerals by reduction, acidolysis and complexation mechanisms. It is an important aspect of biohydrometallugy that requires development to meet future needs. 相似文献