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11.
Maternal adrenalectomy at 7 or 14 days of gestation produced increased cell necrosis within zona reticularis cells on the day of birth and at 24 or 48 h after birth. Small remnants or large portions of adrenocortical cells were present within macrophages. In otherwise normal adrenocortical cells, lipid droplets were incorporated within some mitochondria. Autophagocytosis of single mitochondria was observed within adrenocortical cells. Undoubtedly ultrastructural changes represent stimulation of adrenocortical cells in neonatal rats in response to maternal adrenalectomy.  相似文献   
12.
R. Rakic  V. Bozic-Krstic  T. Pavlica 《HOMO》2011,62(4):307-313
Obesity is a very important issue in developed societies and depends on many factors. The aim of this paper was to determine a possible relationship between overweight, obesity and socioeconomic factors among adolescents in Vojvodina. A cross-sectional anthropometric study was carried out from 2001 to 2004 in towns of Vojvodina, northern Serbia. The research included height and body weight measurements as well as body mass index (BMI) of 1236 schoolboys and 1414 schoolgirls aged 15–18 years. The socioeconomic factors (SES) included parents’ level of education and monthly income per family member. The overweight prevalence of about 10% (85 < P < 95) and the prevalence of obesity of 5% (P > 95) were recorded in both male and female adolescents. A significant correlation (p < 0.01) between all socioeconomic factors was observed in male subjects, although there were no significant differences in the prevalence of overweight and obesity when different categories of subjects set by SES were compared. In females lower rates of the prevalence of overweight and obesity were detected in the subjects whose parents had a university education, but the difference was not significant. Regarding the prevalence of obesity, a significant difference was recorded between females with high and low incomes, those with a high income showing significantly greater prevalence of obesity than females coming from low income families. The results of the research indicate that in Vojvodina the family income is the only factor that significantly correlates with female obesity.  相似文献   
13.
It is well documented that neuropeptide Y (NPY) exerts a wide range of biological functions through at least five NPY Y receptor subtypes (Y1-Y5), but its immunological effects only recently came into focus. Using NPY family peptides and NPY-related receptor-specific peptides as well as Y1 and Y2 receptor antagonists, we have tested which NPY Y receptors are involved in NPY-induced modulation of rat peritoneal macrophage function in vitro. NPY and PYY increased oxidative burst in phorbol myristate acetate (PMA)-stimulated macrophages involving activation of protein kinase C (PKC), and decreased it in zymosan-stimulated cells resembling inhibition of signaling pathways subsequent to binding of zymosan particles for the iC3b fragment receptor on macrophages. The combined treatment with NPY and NPY Y receptor antagonists revealed that NPY-induced potentiation of oxidative burst in PMA-stimulated cells is mediated through Y1 and Y2 receptors, while NPY-induced suppression in zymosan-stimulated cells is mediated through Y2 receptors only. NPY-related peptides differently modulated macrophage function, confirming involvement of NPY Y2 receptor in both potentiation and suppression of oxidative burst in these cells. Additionally, it was shown that NPY Y5 receptor mediated suppression of oxidative burst in PMA- and zymosan-stimulated macrophages. Taken together, the present data reveal an NPY Y1 and Y2/Y5 receptor interaction in NPY-induced modulation of macrophage functions related to inflammation.  相似文献   
14.
A new tiazofurin analogue, 2-(3-amino-3-deoxy-beta-d-xylofuranosyl)thiazole-4-carboxamide (3), was synthesized starting from d-glucose and evaluated for its in vitro antiproliferative activity against a panel of human tumour cell lines. Compound 3 exhibited the most powerful cytotoxicity against K562 cells, being approximately 100-fold more potent than tiazofurin. This analogue was also active against Jurkat, HT-29 and HeLa malignant cells, with respective IC(50) values being ca. 2-, 27- and 17-fold lower than those observed for tiazofurin. Remarkably, compound 3 did not exhibit any significant cytotoxicity towards normal foetal lung MRC-5 cell line.  相似文献   
15.
The aim of this study is to develop a rapid, effect-directed screening method for quality assessment of bee pollen-honey mixtures. The comparative antioxidant potential and phenolic content of honey, bee pollen, and the bee pollen-honey mixtures, was performed using spectrophotometry. The total phenolic content and antioxidative activity of bee pollen-honey mixtures with 20 % bee pollen share were in the range 3.03–3.11 mg GAE/g, and 6.02–6.96 mmol TE/kg, respectively, while mixtures with 30 % bee pollen share contained 3.92–4.18 mg GAE/g, and 9.69–10.11 mmol TE/kg. Chromatographic fingerprint of bee pollen-honey mixtures was performed by high-performance thin-layer chromatography with conditions developed by authors and reported for the first time. Fingerprint analysis hyphenated with chemometrics enabled authenticity assessments of honey in mixtures. Results indicate that bee pollen-honey mixtures represent a food with highly, both, nutritious characteristics and health-promoting effect.  相似文献   
16.
Hemp fibers are very interesting natural material for textile and technical applications now. Applying hemp fibers to the apparel sector requires improved quality fibers. In this paper, hemp fibers were modified with sodium hydroxide solutions (5% and 18% w/v), at room and boiling temperature, for different periods of time, and both under tension and slack, in order to partially extract noncellulosic substances, and separate the fiber bundles. The quality of hemp fibers was characterised by determining their chemical composition, fineness, mechanical and sorption properties. The modified hemp fibers were finer, with lower content of lignin, increased flexibility, and in some cases tensile properties were improved. An original method for evaluation of tensile properties of hemp fibers was developed.  相似文献   
17.
Genetically transformed alfalfa (Medicago sativa L., cv. Zajearska 83) plantlets were obtained by inoculating somatic embryos with Agrobacterium tumefaciens strains A281/pGA472 and LBA4404/pBI121. Single somatic embryos, 5–7 mm long, were released from a repetitively embryogenic culture, wounded, and cocultivated with the bacteria. The agar-solidified culture medium contained mineral salts, vitamins, 40 g l–1 sucrose, 1 g l–1 yeast extract and 0.05 mg l–1 BA. Five clones, transformed with A281/pGA472, and 4 clones transformed with LBA4404/pBI121, were selected for proliferation by repetitive somatic embryogenesis, on media containing 100 mg l–1 of kanamycin. The transformation of kanamycin-resistant clones was confirmed by assaying the activity of neomycin phosphotransferase II and/or -glucuronidase enzymes, and by the Southern blot analysis. It is suggested that the transformation/regeneration system based on somatic embryogenesis may be suitable for establishing transgenic alfalfa lines. The relatively low frequency of embryo transformation is compensated for by abundant proliferation in secondary somatic embryogenesis.Abbreviations BA 6-benzyladenine - GUS -glucuronidase - Km kanamycin - NPTII neomycin phosphotransferase II - X-gluc 5-bromo-4-chloro-3-indolyl--glucuronic acid - BM basal medium  相似文献   
18.
The use of tooth cementum annulations for age determination has been deemed promising, exhibiting high correlations with chronological age. Despite its apparent potential, to date, the tooth cementum annulations method has been used rarely for estimating ages in archaeological populations. Here we examine the readability of cementum annulations and the consistency of age estimates using a sample of 116 adults from the Iron Gates Gorge Mesolithic/Neolithic series. Our examination of the method pointed to several sources of error that call into question the use of this method for estimating the chronological ages of archaeologically derived dental samples. The poor performance of the method in our analysis might be explained by taphonomic influences, including the effect of chemical and biological agents on dental microstructures. Am J Phys Anthropol 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
19.
This paper describes a case of asymptomatic multifocal actinomycosis of the greater omentum which was detected accidentally in a patient who was suspected of uterus myoma. The patient was a 40 year old woman who had a copper intrauterine contraceptive device (IUCD) for three years. After the gynecological examination and pelvic ultrasound she was diagnosed with sub serous myoma of uterus. Since she did not give a birth it was suggested to have myoma enucleating. However during the surgery a dermoid teratoma of the right ovary was detected so it was removed together with tumor and there were two thickenings on the greater omentum, suspicious of inflammation, whereas one grew together with the front abdominal wall. Due to these conditions, she had partial omentectomy done and omentum was sent for path histological examination. The path histological examination confirmed it to be actinomycosis. The patient had an intensive antibiotic therapy prescribed (Penicillin) in order to prevent a disease relapse because we could not be sure whether the remaining part of omentum was affected by microscopic actinomycosis.  相似文献   
20.
The frequency of micronuclei (MN) induced by pentachlorophenol (PCP) in haemocytes of zebra mussel, Dreissena polymorpha Pall. and great ramshorn snail, Planorbarius corneus L. was determined over a 14 days of exposure (sampling after 4, 7 and 14 days) under laboratory conditions. PCP doses for zebra mussel ranged from 10 to 150 microg/l, and for ramshorn snail from 10 to 450 microg/l. Micronuclei were detected after bisbenzimide fluorescent staining. Positive responses were observed in both species. The mean MN frequencies in treated mussels ranged between 0.69 and 7.50 per thousand, and between 2.07 and 13.80 per thousand in treated snails. The spontaneous MN levels in mussels averaged from 0.5 to 2.75 per thousand, and in snails from 1.56 to 2.00 per thousand. Our results suggest that haemolymph of both species represent an appropriate test tissue in environmental genotoxicity assessment.  相似文献   
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