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1.
ABSTRACTAlthough communication about sexuality is a significant pathway through which peers influence adolescent sexual development, little research has examined the role of peer networks in the use of sexualized media. We applied a social network approach to assess the role of close peers in adolescent pornography use and sexting in a sample of Croatian high school students. Sexual conversation networks’ characteristics did not correlate with pornography use. In contrast, sexting was associated with the proportion of same gender peers, the proportion of older peers and the proportion of sexually experienced peers in the network – pointing to the role of peer influence. Participants’ gender did not moderate these associations. Specific mechanisms underlying the observed associations and the role of peer selection remain important tasks for future research. 相似文献
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The temporal bones from fetuses with known autosomal trisomy syndromes were examined histopathologically after spontaneous or induced abortions. Fetal ages dated from the 17th to the 24th week of pregnancy. In all, 17 temporal bones from nine fetuses were studied and included seven cases of Down's syndrome and two of Edwards' syndrome. Temporal bones from fetuses with Down's syndrome had more abnormalities of the external and middle ears than of the inner ear. The bones from the fetuses with Edwards' syndrome showed abnormalities of the external or middle ear and retarded development of the inner ear (failed ossification of the otic capsule and unformed organ of Corti). 相似文献
6.
Mirna SuČIĆ Dubravka Boban Mirjana MarkoviĆ-glamoČak Mladen PetroveČki Matko MaruŠIĆ Boris Labar 《Medical oncology (Northwood, London, England)》1992,9(1):41-45
Cytochemical analysis of leukemic blasts from 46 patients with acute myeloblastic M2 leukemia (according to the FAB classification)
was performed before and after cytostatic therapy, and compared with findings obtained in 20 age- and sex-matched control
subjects. Cytochemical findings for myeloperoxidase (MPO), Sudan black B, acid phosphatase and alpha-naphthyl-acetate esterase
(ANAE) were related to the achievement of the first complete remission (CR),i.e. data were compared after the patients had been divided into CR and non-CR groups. The analysis clearly showed that a high
proportion of myeloperoxidase- and, to a lesser extent, Sudan black B-positive blasts before treatment may have constituted
a significantly unfavourable prognostic factor. 相似文献
7.
Gordana Kocic Gordana Bjelakovic Dusica Pavlovic Tatjana Jevtovic Voja Pavlovic Dusan Sokolovic Jelena Basic Snezana Cekic Tatjana Cvetkovic Radivoj Kocic Svetlana Stojanovic 《Hepatology research》2007,37(8):637-646
Aim: Fas membrane-associated polypeptide antigen is a receptor molecule responsible for apoptosis-mediated signals. In animal models of acute viral hepatitis, apoptosis of hepatocytes is mediated by Fas-death receptors; therefore, the aim of this study was to evaluate the effect of interferon (IFN)-alpha on apoptotic markers and nuclease activity against different coding and non-coding single and double stranded RNAs during Fas-induced liver apoptosis. Methods: An in vivo experiment was performed with simultaneous administration of anti-Fas (CD95) antibodies and IFN-alpha, and an in vitro experiment was performed in hepatocyte cultures treated with anti-Fas antibodies and IFN-alpha. Results: Detection of apoptosis using Annexin V-FITC/propidium iodide, Bcl-2 and Bax expression in hepatocyte cultures confirmed the appearance of early apoptotic events and progression toward late apoptosis after anti-Fas antibody treatment. IFN-alpha had a tendency to retard the apoptosis process in Fas-induced apoptosis by increasing the number of viable cells and decreasing the number of cells in late apoptosis, by increasing the percentage of Bcl-2 positive cells, by decreasing the percentage of Bax positive cells, and by decreasing the nuclease activity compared to the anti-Fas antibody treated group. Total DNA and RNA concentration was much reduced in the Fas group and DNA fragmentation assay provided evidence for increased DNA degradation. Enhanced nuclease activity against DNA, rRNA, poly(A), poly(C), poly(U), poly(I:C), and poly(A:U) was manifested in the anti-Fas antibody treated group, except for the inhibitory-bound alkaline RNase. Conclusions: The results demonstrate that the RNA-degrading pathway in Fas-induced apoptosis can accelerate the liberation of the latent enzyme from the inhibitor complex. IFN-alpha prevented enormous, Fas-ligand induced degradation of all the substrates used in this experimental study, most probably due to similarities in the signal transduction pathways. Investigations of death receptor-induced apoptosis may lead to novel treatment combinations for patients with acute or chronic liver diseases. 相似文献
8.
Eva Dragomirecka William R. Lenderking Lucie Motlova Eva Goppoldova Pavla Šelepova 《Quality of life research》2006,15(2):307-312
The Schwartz Outcomes Scale-10 (SOS-10) is a 10-item scale developed to measure the effectiveness of psychiatric treatments.
Using standard methodology, we translated the scale into Czech and examined the psychometric properties of the Czech version.
207 in-patients admitted to Prague Psychiatric Center were included in the study. All patients completed the SOS at admission
and discharge. The SOS-10 scale was also administered to 170 persons from the general population. Reliability, validity and
sensitivity to treatment change of the Czech SOS-10 were analyzed. The Cronbach’s α coefficient was 0.92. The item-total correlation coefficients varied from 0.56 to 0.82. The SOS-10 correlated well with condition-specific
measures including depression (BDI) and anxiety (BAI) and a global self-rated symptom severity scale (CGI). The SOS-10 also
had significant correlations with the Health, Basic needs, Relationship, and Leisure time domains of the Czech version of
the Subjective Quality of Life Analysis (SQUALA-CZ). The scale discriminated well between patients and controls, with patients
scoring significantly lower on all SOS items. The patient sample’s admission and discharge scores were significantly different,
indicating that the scale is sensitive to treatment changes. We concluded that the Czech SOS-10 is valid with reliability
and factor structure similar to the American language version. 相似文献
9.
Tomáš Šimůnek Martin Štěrba Olga Popelová Michaela Adamcová Radomír Hrdina Vladimír Geršl 《Pharmacological reports : PR》2009,61(1):154-171
The risk of cardiotoxicity is the most serious drawback to the clinical usefulness of anthracycline antineoplastic antibiotics, which include doxorubicin (adriamycin), daunorubicin or epirubicin. Nevertheless, these compounds remain among the most widely used anticancer drugs. The molecular pathogenesis of anthracycline cardiotoxicity remains highly controversial, although the oxidative stress-based hypothesis involving intramyocardial production of reactive oxygen species (ROS) has gained the widest acceptance. Anthracyclines may promote the formation of ROS through redox cycling of their aglycones as well as their anthracycline-iron complexes. This proposed mechanism has become particularly popular in light of the high cardioprotective efficacy of dexrazoxane (ICRF-187). The mechanism of action of this drug has been attributed to its hydrolytic transformation into the iron-chelating metabolite ADR-925, which may act by displacing iron from anthracycline-iron complexes or by chelating free or loosely bound cellular iron, thus preventing site-specific iron-catalyzed ROS damage. However, during the last decade, calls for the critical reassessment of this “ROS and iron” hypothesis have emerged. Numerous antioxidants, although efficient in cellular or acute animal experiments, have failed to alleviate anthracycline cardiotoxicity in clinically relevant chronic animal models or clinical trials. In addition, studies with chelators that are stronger and more selective for iron than ADR-925 have also yielded negative or, at best, mixed outcomes. Hence, several lines of evidence suggest that mechanisms other than the traditionally emphasized “ROS and iron” hypothesis are involved in anthracycline-induced cardiotoxicity and that these alternative mechanisms may be better bases for designing approaches to achieve efficient and safe cardioprotection. 相似文献
10.
We investigated spatial relations of the pterygoid hamuli to the hard palate on 65 skull bases: 31 disarticulated sphenoidal bones from the newborn up to 9 years of age, 19 skulls of adult skeletons (21-59 age group), and 15 skulls aged 60-100 years. We measured: (a) width of the hard palate in the choanal region, (b) length of the hamulus, (c) inclination of the hamulus from the perpendicular line, and (d) distance between the tips of the contralateral hamuli. The width of the hard palate in the choanal region was smallest in children (mean +/- standard deviation, 21.5 +/- 2.6 mm) compared with adult skulls (26.8 +/- 2.3 mm in the 21-59 age group and 25.4 +/- 1.9 mm in the 60-100 age group; P<0.05, one-way analysis of variance (ANOVA) and Student-Newman-Keuls post hoc test). Children had the shortest hamulus (3.6 +/- 1.5mm), and its length increased in the adult age group to 6.9+1.7mm (P<0.05), and then again decreased to 5.0 +/- 1.9 mm in the 60-100 age group (P<0.05 vs. adults and children). The distance between the tips of the contralateral hamuli and their lateral inclination from the perpendicular plane were also greater in the adult age group (38.0 +/- 2.7mm and 35.9 +/- 13.7 degrees, respectively) than either in children (31.0 +/- 3.7mm and 19.6 +/- 12.1 degrees) or the elderly (32.7 +/- 3.9mm and 19.7 +/- 10.3 degrees) (P<0.05). Our study showed that the anatomical measures of the pterygoid hamulus and its relation to the surrounding structures change with age, and occur with the changes in the function of pharyngeal and palatal muscles in deglutition. These changes may have clinical relevance for sleep apnoea and snoring. 相似文献