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41.
Thirty five females and 15 males of New Zealand White mature rabbits about 6 months of age, were assigned to 1–5 dietary treatments (7 does+3 bucks for each): uncontaminated control diet, naturally aflatoxin contaminated diet without or with 1,2 and 3% bentonite. Rabbit fed with the aflatoxin-diet had a decreased (P<0.01 or 0.05) physical semen characteristics of bucks and a reproductive performance traits of does. The values of conception rate (%), gestation length (days), litter size (n) and litter weights (g) at birth and viability (%) of litters of doe rabbits, fed with the aflatoxin-diet, recorded, respectively: 64.5; 31.0; 4.4; 275.0 and 57.1 versus 85.6; 30.3; 7.9; 508.0; and 100 for those fed with the uncontaminated diet. Addition of bentonite to the aflatoxin contaminated diet improved in general the physical semen characteristics of buck and reproductive performance traits of doe rabbits. The results of the study demonstrate that adding 1% of Egyptian raw bentonite to the naturally aflatoxin contaminated rabbit diets can provide an effective, cheap and safe practical technique for preventing the aflatoxicosis in mature rabbits. 相似文献
42.
The flexibility and self-healing properties of animal cell surface membranes are well known. These properties have been best exploited in various micrurgical studies on living cells (2, 3), especially in amoebae (7, 20). During nuclear transplantation in amoebae, the hole in the membrane through which a nucleus passes can have a diameter of 20-30 μm, and yet such holes are quickly sealed, although some cytoplasm usually escapes during the transfer. While enucleating amoebae in previous studies, we found that if a very small portion of a nucleus was pushed through the membrane and exposed to the external medium, the amoeba expelled such a nucleus on its own accord. When this happened, a new membrane appeared to form around the embedded portion of the nucleus and no visible loss of cytoplasm occurred during nuclear extrusion. In the present study, we examined amoebae that were at different stages of expelling partially exposed nuclei, to follow the sequence of events during the apparent new membrane formation. Unexpectedly, we found that a new membrane is not formed around the nucleus from inside but a hole is sealed primarily by a constriction of the existing membrane, and that cytoplasmic filaments are responsible for the prevention of the loss of cytoplasm. 相似文献
43.
Cisplatin cytotoxicity is enhanced with zoledronic acid in A549 lung cancer cell line: preliminary results of an in vitro study 总被引:2,自引:0,他引:2
Ozturk OH Bozcuk H Burgucu D Ekinci D Ozdogan M Akca S Yildiz M 《Cell biology international》2007,31(9):1069-1071
We tested whether zoledronic acid, a biphosphonate with proposed apoptotic activity, augmented the cytotoxicity of cisplatin and/or gemcitabine in A549 lung cancer cell line. This cell line was subjected to different concentrations of the above chemotherapeutic agents and zoledronic acid. Cytotoxicity was assessed by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide) assay. Particularly, zoledronic acid in 100 micromolar (microM) concentration augmented the cytotoxicity by cisplatin 1microg/ml from 25% to 70% (Z=3.22, P=0.0072). A significant portion of cells underwent apoptosis with or without zoledronic acid, but more so with the combination treatment as assessed by an Annexin V-FITC apoptosis detection kit. However, 100microM zoledronic acid showed 50% cytotoxicity on its own, but failed to improve cytotoxicity by Gemcitabine. Thus, we show for the first time in a lung cancer cell line that zoledronic acid bears cytotoxic potential on its own and in conjunction with cisplatin. The clinical potential of this finding should be further studied. 相似文献
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45.
Obesity‐induced mitochondrial dysfunction in porcine adipose tissue‐derived mesenchymal stem cells
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46.
Compensatory substitutions and the evolution of the mitochondrial 12S rRNA gene in mammals 总被引:5,自引:2,他引:3
12S ribosomal RNA (rRNA) gene sequences from a suite of mammalian taxa (13
placentals, 4 marsupials, 1 monotreme), for which phylogenetic
relationships are well established based on independent criteria, were
employed to study the evolution of this gene. Phylogenetic analysis of 12S
sequences produces a phylogeny that agrees with expectations. Base
composition provides evidence for directional symmetrical substitution
pressure in loops; in stems, base composition is much more even. Rates of
nucleotide substitution are lower in stems than loops. Patterns of
nucleotide substitution show an overall preference for transitions over
transversions, with this difference more profound in stems than loops.
Among different transversion pathways, there is a wide range of
transformation frequencies. An analysis of compensatory substitutions shows
that there is strong evidence for their occurrence and that a weighting
factor of 0.61 should be applied in phylogenetic analyses to account for
the dependence of mutations at stem positions relative to positions where
changes are independent. Among stem variables (i.e., stem length,
interaction distance, substitution rates, G+C content, and the percentage
of bases that are paired), several significant correlations were
discovered, but stem length and interaction distance are uncorrelated with
other variables.
相似文献
47.
Arife Pınar Ekinci Nimet Baltaş Ahmet Adıgüzel 《Journal of enzyme inhibition and medicinal chemistry》2016,31(2):325-331
The lipase was partially purified by ion exchange chromatography and gel filtration column chromatography, and was characterized from Geobacillus stearothermophilus AH22 strain. The lipase was purified 18.3-folds with 19.7% recovery. The lipase activity was determined by using p-nitrophenyl esters (C2–C12) as substrates. The Km values of the enzyme for these substrates were found as 0.16, 0.02, 0.19 and 0.55?mM, respectively, while Vmax values were 0.52, 1.03, 0.72 and 0.15?U?mg?1. The enzyme showed maximum activity at 50?°C and between pH 8.0 and 9.0. The enzyme was found to be quite stable at pH range of 4.0–10.0, and thermal stability between 50 and 60?°C. It was found that the best inhibitory effect of the enzyme activity was of Hg2+. The inhibitory effect as orlistat, catechin, propyl paraben, p-coumaric acid, 3,4-dihydroxy hydro-cinnamic acid was examined. These results suggest that G. stearothermophilus AH22 lipase presents very suitable properties for industrial applications. 相似文献
48.
We investigated the prevalence and phenotypic variation of Candida species in oral lichen planus (OLP) and the therapeutic implications of our findings. Eighty patients with clinically and histopathologically confirmed cases of OLP (64 non-erosive, 16 erosive) and a control group of 80 healthy individuals with no predisposing factors for oral candidiasis were examined for evidence of Candida infection. Oral swabs and smears were obtained for cytology and culture. Identification, speciation and antifungal susceptibility tests of Candida isolates were performed using an automated microbial identification system. Fifty percent of erosive OLP cases, 28% of non-erosive cases and none of the controls showed evidence of Candida. Candida albicans was found predominantly in non-erosive OLP, while other Candida species were predominate in erosive OLP. Non-Candida albicans isolates (C. glabrata, C. krusei) were resistant to the commonly used antifungals, clotrimazole and fluconazole. Candida infection is common in cases of OLP. We recommend antifungal sensitivity testing prior to antifungal therapy for the erosive form of OLP. 相似文献
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50.
Raynner RD Barboza Wedson de MS Souto José da S Mourão 《Journal of ethnobiology and ethnomedicine》2007,3(1):1-14