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排序方式: 共有252条查询结果,搜索用时 15 毫秒
121.
122.
Giulia Maurizi Antonella Poloni Domenico Mattiucci Spartaco Santi Angela Maurizi Valerio Izzi Angelica Giuliani Stefania Mancini Maria Cristina Zingaretti Jessica Perugini Ilenia Severi Massimo Falconi Marco Vivarelli Maria Rita Rippo Silvia Corvera Antonio Giordano Pietro Leoni Saverio Cinti 《Journal of cellular physiology》2017,232(10):i-i
123.
Rosario Barone Alessandro Pitruzzella Antonella Marino Gammazza Francesca Rappa Monica Salerno Fulvio Barone Claudia Sangiorgi Daniela D'Amico Nicola Locorotondo Francesca Di Gaudio Luigi Cipolloni Valentina Di Felice Stefania Schiavone Venerando Rapisarda Gabriele Sani Amos Tambo Francesco Cappello Emanuela Turillazzi Cristoforo Pomara 《Journal of cellular and molecular medicine》2017,21(8):1636-1647
The aim of this study was to investigate whether nandrolone decanoate (ND) use affects testosterone production and testicular morphology in a model of trained and sedentary mice. A group of mice underwent endurance training while another set led a sedentary lifestyle and were freely mobile within cages. All experimental groups were treated with either ND or peanut oil at different doses for 6 weeks. Testosterone serum levels were measured via liquid chromatography–mass spectrometry. Western blot analysis and quantitative real‐time PCR were utilized to determine gene and protein expression levels of the primary enzymes implicated in testosterone biosynthesis and gene expression levels of the blood–testis barrier (BTB) components. Immunohistochemistry and immunofluorescence were conducted for testicular morphological evaluation. The study demonstrated that moderate to high doses of ND induced a diminished serum testosterone level and altered the expression level of the key steroidogenic enzymes involved in testosterone biosynthesis. At the morphological level, ND induced degradation of the BTB by targeting the tight junction protein‐1 (TJP1). ND stimulation deregulated metalloproteinase‐9, metalloproteinase‐2 (MMP‐2) and the tissue inhibitor of MMP‐2. Moreover, ND administration resulted in a mislocalization of mucin‐1. In conclusion, ND abuse induces a decline in testosterone production that is unable to regulate the internalization and redistribution of TJP1 and may induce the deregulation of other BTB constituents via the inhibition of MMP‐2. ND may well be considered as both a potential inducer of male infertility and a potential risk factor to a low endogenous bioavailable testosterone. 相似文献
124.
The paper attempts to describe Italian mammal diversity in an evolutionary context. With 122 species according latest researches, Italy holds the richest mammal assemblage among European countries. Specific taxa are often represented by clearly distinctive lineages and several of them appear restricted to the Italian peninsula. Poor knowledge of taxonomy and uncritical application of IUCN threat categories at the national level could produce a flawed set of conservation priorities, independently from the rigorous application of the proposed guidelines for national Red List assessments. Furthermore, classical conservation assessments and protective legislation only consider traditionally named taxa, often privileging insular taxa of artificial origin but neglecting most of the results of genetic and molecular studies on intraspecific variation. The aim of the present work is to outline the need to incorporate phylogenetic and biogeographic data in the assessment of conservation priorities among mammals in Italy, in order to maximise the national contribution to biodiversity conservation in Europe. To this end, distribution, threat status, intraspecific and supraspecific taxonomy of the native mammal fauna should be analysed in a global context. Phylogeographic patterns emerging from previous studies indicate the general inadequacy of continental European populations serving as sources for re-stocking or re-introductions operations in Italy and the other European peninsulas. Thus the importance of integrating international guidelines on reintroductions with a clear understanding of national biogeographical peculiarities is highlighted. 相似文献
125.
Plasma Copper, Zinc, and Selenium Levels and Correlates with Metabolic Syndrome Components of Lebanese Adults 总被引:1,自引:0,他引:1
Obeid O Elfakhani M Hlais S Iskandar M Batal M Mouneimne Y Adra N Hwalla N 《Biological trace element research》2008,123(1-3):58-65
Zinc, copper, and selenium statuses were reported to be linked to the development of chronic diseases, especially coronary heart disease (CHD). Metabolic syndrome, a known CHD risk factor, was found to be highly prevalent in Lebanon. Nevertheless, no data are available on the statuses of plasma zinc, copper, and selenium, especially in terms of their relation to the components of the metabolic syndrome. A sample of 398 men and women aged 18-65 years was drawn from 23 health centers across Lebanon; anthropometric measurements and biochemical analyses of fasting plasma samples were performed. Subjects were found to have normal plasma statuses of copper and selenium but were at elevated risk of zinc deficiency. Plasma selenium levels correlated positively with all the components of the metabolic syndromes, while that of copper correlated only with total, high-density lipoprotein and low-density lipoprotein cholesterol. Plasma zinc did not correlate with any of the metabolic syndrome components. 相似文献
126.
de Moraes Lidia M.P. Filho Spartaco Astolfi Ulhoa Cirano J. 《World journal of microbiology & biotechnology》1999,15(5):561-564
A fusion gene containing the Bacillus subtilis -amylase gene and Aspergillus awamori glucoamylase cDNA was expressed in Saccharomyces cerevisiae. The resulting bifunctional fusion protein having both -amylase and glucoamylase activities secreted into the culture medium was purified to apparent homogeneity by affinity chromatography and gel filtration on Sephadex G-100. The enzyme had an apparent molecular mass of 150 kDa and showed an optimum pH and temperature of 6.0 and 60 °C, respectively. The main hydrolysis products from soluble starch were glucose and maltose. 相似文献
127.
Sani RK Peyton BM Smith WA Apel WA Petersen JN 《Applied microbiology and biotechnology》2002,60(1-2):192-199
The reduction of Cr(VI), Fe(III), and U(VI) was studied using three recently isolated environmental Cellulomonas sp. (WS01, WS18, and ES5) and a known Cellulomonas strain ( Cellulomonas flavigena ATCC 482) under anaerobic, non-growth conditions. In all cases, these cultures were observed to reduce Cr(VI), Fe(III), and U(VI). In 100 h, with lactate as electron donor, the Cellulomonas isolates (500 mg/l total cell protein) reduced nitrilotriacetic acid chelated Fe(III) [Fe(III)-NTA] from 5 mM to less than 2.2 mM, Cr(VI) from 0.2 mM to less than 0.001 mM, and U(VI) from 0.2 mM to less than 0.12 mM. All Cellulomonas isolates also reduced Cr(VI), Fe(III), and U(VI) in the absence of lactate, while no metal reduction was observed in either the cell-free or heat-killed cell controls. This is the first report of Cellulomonas sp. reducing Fe(III) and U(VI). Further, this is the first report of Cellulomonas spp. coupling the oxidation of lactate, or other unknown electron donors in the absence of lactate, to the reduction of Cr(VI), Fe(III), and U(VI). 相似文献
128.
Santi S Bianco MC Blasi F Spisni E Riccio M Toni M Griffoni C Tomasi V 《Journal of gravitational physiology : a journal of the International Society for Gravitational Physiology》2002,9(1):P283-P284
In hypogravity conditions unloading of skeletal muscle fibres causes alterations in skeletal muscle structure and functions including growth, gene expression, cell differentiation, cytoskeletal organization, contractility and plasticity. Recent studies have identified sphingosine I -phosphate (SPP) as a lipid mediator capable of eliciting intracellular Ca2+ transients, cell proliferation, differentiation, suppression of apoptosis, as well as cell injury repair. The aim of this research is to evaluate a possible involvement of SPP in skeletal muscle cells differentiation and repair from space-flight damage. Particularly, we investigated the Ca2+ sources and the changes on the cytoskeletal rearrangement induced by SPP in a mouse skeletal (C2C12) myoblastic cell line. Confocal fluorescence imaging revealed that SPP elicited Ca2+ transients which propagated throughout the cytosol and nucleus. This response required extracellular and intracellular Ca2+ mobilization. SPP also induced cell contraction through a Ca2(+)- independent/Rho-dependent pathway. The nuclear Ca2+ transients are suggestive for an action of SPP in the differentiation program and damage repair. 相似文献
129.
Roberto PG Kashima S Soares AM Chioato L Faça VM Fuly AL Astolfi-Filho S Pereira JO França SC 《Protein expression and purification》2004,37(1):102-108
The phospholipase A2 (PLA2, E.C. 3.1.1.4) superfamily is defined by enzymes that catalyze the hydrolysis of the sn-2 bond of phosphoglycerides. Most PLA2s from the venom of Bothrops species are basic proteins, which have been well characterized both structurally and functionally, however, little is known about acidic PLA2s from this venom. Nevertheless, it has been demonstrated that they are non-toxic, with high catalytic and hypotensive activities and show the ability to inhibit platelet aggregation. To further understand the function of these proteins, we have isolated a cDNA that encodes an acidic PLA2 from a cDNA library prepared from the poly(A)+ RNA of venom gland of Bothrops jararacussu. The full-length nucleotide sequence of 366 base pairs encodes a predicted gene product with 122 amino acid with theoretical isoelectric point and size of 5.28 and 13,685 kDa, respectively. This acidic PLA2 sequence was cloned into expression vector pET11a (+) and expressed as inclusion bodies in Escherichia coli BL21(DE3)pLysS. The N-terminal amino acid sequence of the 14 kDa recombinant protein was determined. The recombinant acidic PLA2 protein was submitted to refolding and to be purified by RP-HPLC chromatography. The structure and function of the recombinant protein was compared to that of the native protein by circular dichroism (CD), enzymatic activity, edema-inducing, and platelet aggregation inhibition activities. 相似文献
130.
Welders or metal workers not being an exception are exposed to metals ions or oxides (fumes) at trace concentrations either through direct contact supplementation at occupational sites or indirectly through uptake from contaminated food, water or contaminated soil, dust, or air. The study aims to determine the effects of welding fumes exposure on haematological parameters in blood of experimental animals. The fumes were collected from welding sites during the activity by a skilled welder. 130 male experimental animals were utilized and made into 13 groups. 12 groups were given dosages calculated to correspond to real life workers exposure regimes and 1 group served as control. The dosages were administered intratracheally after been anaesthetized weekly for 12 weeks. The animals were sacrificed and whole blood samples were taken which was then subjected to haematological analysis. The parameters have revealed changes in values whereby RBC, WBC, % lymphocytes, HGB, HCT, MCV, MCH, PLT, PCT and P-LCC have exceeds the control groups values. There was an increase across the treatment groups. However, lymphocytes, MID, granulocytes, % granulocytes, MCHC and MPV have values which were less than the control and no different from one another statistically. This indicates that exposure to welding fumes could cause alterations to most RBC, WBC and PLT indices majorly by effecting an increase. Further studies should be carried out on the response of other markers of toxicity so as to have a broad perception of the effects. 相似文献