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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
2.
Soluflazine, a specific adenosine transport inhibitor, was intracerebroventricularly administered to rats in a dose range of 10, 25, and 50 nmoles. At a dose of 50 nmoles, soluflazine decreased waking and increased sleep during the first hour of EEG recording. Our previous work has shown that chronic intracerebroventricular administration of soluflazine to rats decreased radioligand binding to adenosine A1 and A2 receptors in specific brain regions. The present data show that administration of an adenosine transport inhibitor to rats produces a transient hypnotic effect presumably through increases in synaptic adenosine levels. 相似文献
3.
Sex Therapy in a Cultural Context 总被引:1,自引:0,他引:1
4.
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
5.
Autologous blood stem cell transplants (ABSCT) are increasingly used for the treatment of haematological malignancies. The use of hemopoietic growth factors, in conjunction with stem cell mobilization by chemotherapeutic agents, has permitted successful harvests requir ing only a few leukaphereses; cells mobilized in this manner contain a relatively large number of committed precursors of all lineages, as well as early progenitor cells capable of main taining long-term haemopoiesis. Haematological recovery after ABSCT is rapid, thereby sig nificantly shortening the period of post-chemotherapy neutropenia and thrombocytopenia. Furthermore, blood-derived grafts may contain fewer malignant cells than the bone marrow cells. The preliminary results have been so encouraging that it is envisaged that in myeloma, Hodgkin's disease and non-Hodgkin lymphomas, ABSCT may eventually replace autologous marrow transplantation. 相似文献
6.
Summary The activity of glutamate dehydrogenase, the enzyme of glutamate degradation, was measured in platelets of 27 healthy controls and 85 patients with different degenerative cerebellar and/or basal ganglia disorders. A group of 7 patients was selected with slowly progressive multiple-system atrophy, in whom a clinical diagnosis of olivopontocerebellar atrophy appeared tenable, with decreased activity of glutamate dehydrogenase (38% of the mean control value). In 4 patients data on inheritance were compatible with the genetic pattern of autosomal recessive inheritance, while 3 patients were sporadic cases. In an effort to define this group of patients more precisely, it is suggested that decreased activity of glutamate dehydrogenase induces an increase in extracellular glutamate levels in the central nervous system with subsequent development of excitotoxicity. 相似文献
7.
Applying spatial distribution analysis techniques to classification of 3D medical images 总被引:3,自引:0,他引:3
Pokrajac D Megalooikonomou V Lazarevic A Kontos D Obradovic Z 《Artificial intelligence in medicine》2005,33(3):261-280
OBJECTIVE: The objective of this paper is to classify 3D medical images by analyzing spatial distributions to model and characterize the arrangement of the regions of interest (ROIs) in 3D space. METHODS AND MATERIAL: Two methods are proposed for facilitating such classification. The first method uses measures of similarity, such as the Mahalanobis distance and the Kullback-Leibler (KL) divergence, to compute the difference between spatial probability distributions of ROIs in an image of a new subject and each of the considered classes represented by historical data (e.g., normal versus disease class). A new subject is predicted to belong to the class corresponding to the most similar dataset. The second method employs the maximum likelihood (ML) principle to predict the class that most likely produced the dataset of the new subject. RESULTS: The proposed methods have been experimentally evaluated on three datasets: synthetic data (mixtures of Gaussian distributions), realistic lesion-deficit data (generated by a simulator conforming to a clinical study), and functional MRI activation data obtained from a study designed to explore neuroanatomical correlates of semantic processing in Alzheimer's disease (AD). CONCLUSION: Performed experiments demonstrated that the approaches based on the KL divergence and the ML method provide superior accuracy compared to the Mahalanobis distance. The later technique could still be a method of choice when the distributions differ significantly, since it is faster and less complex. The obtained classification accuracy with errors smaller than 1% supports that useful diagnosis assistance could be achieved assuming sufficiently informative historic data and sufficient information on the new subject. 相似文献
8.
Stevanović R Tiljak H Stanić A Varga S Not T Jovanović A 《Acta medica Croatica : c?asopis Hravatske akademije medicinskih znanosti》2005,59(3):267-271
A consensus reached by the medical profession, Croatian Institute of Health Insurance, Croatian Institute of Public Health, and Ministry of Health constitutes a solution to the problem of a data standard required in building an information system for primary health care. This consists of accepting ICPC-2 as a data standard for our Family Medicine, Pediatrics and Women's Health. The classification structure of the International Classification of Primary Care allows, recommends and urges that special codes be established by individual states or local authorities when registering patients' reasons for seeking medical aid or medical procedures. Namely, it urges the authorities to set the codes for such reasons about which a state or local agreement or determination has been made. This is the first public presentation of the proposal Croatia's Additions to the International Classification of Primary Care. They are essential to its implementation in our health insurance, health statistics and medical informatics. 相似文献
9.
Miodrag ?oli? Nada Pejnovi? Milena Kataranovski Ljiljana Popovi? Sonja Ga?I? Aleksandar Duji? 《Clinical & developmental immunology》1992,2(2):151-160
Rat thymic epithelial cells (TEC) in long-term culture were characterized by
anticytokeratin monoclonal antibodies (mAbs) and electron microscopy. Phenotypic
analysis performed by a large panel of mAbs showed that the highest percentage of
these cells was of the subcapsular/medullary type.
Recombinant rat interferon (IFN)-gamma up-regulated class-I and class-II MHC
expression by TEC in culture as confirmed by immunohistochemistry and flow
cytometry, but did not significantly alter other cell markers. TEC supernatants of IFN-gamma-
treated cultures showed higher interleukin-6 (IL-6) activity, compared to the
control, as determined by proliferation of the IL-6-sensitive B9-cell line. Increased IL-6
activity was probably not a consequence of increased TEC number in IFN-gammatreated
cultures because IFN did not significantly stimulate TEC proliferation in vitro. In
contrast, IL-6 significantly stimulated TEC proliferation, indicating that this cytokine is
not only a regulatory molecule for T-cell proliferation, but could also be an autocrine
growth factor for thymic epithelium. 相似文献
10.
The opening of sarcolemmal K(ATP) channels is considered to be an important endogenous cardioprotective mechanism. On the other hand, age-dependent changes in the myocardial susceptibility to ischemia and hypoxia have been observed in different species, including humans. Here, we have hypothesized that aging might be associated with the changes in sarcolemmal K(ATP) channels. Therefore, the main objective of the present study was to establish whether aging changes expression of cardiac sarcolemmal ATP-sensitive K+ (K(ATP)) channels. RT-PCR using primers specific for K(ATP) channel subunits, Kir6.2, Kir6.1 and SUR2A subunits was performed using total RNA from guinea-pig ventricular tissue. Whole cell electrophysiology was done on isolated guinea-pig ventricular cardiomyocytes. Western blotting using anti-Kir6.2 and anti-SUR2A antibodies was performed on cardiac membrane fraction. Tissue and cells were harvested from young and old, male and female guinea-pigs. RT-PCR analysis did not reveal significant age-related changes in levels of Kir6.1 or Kir6.2 mRNAs. However, levels of SUR2A were significantly lower in old than in young females. Such age-differences were not observed with cardiac tissue from male animals. In both old and young males, pinacidil (100 microM) induced outward currents. The difference between current density of pinacidil-sensitive component in females, but not males, was statistically significant. Western blotting analysis revealed higher levels of Kir6.2 and SUR2A proteins in cardiac membrane fraction from young than old females. The present study demonstrates that in females, but not males, aging is associated with decrease in number of cardiac K(ATP) channels which is due to decrease in levels of the SUR2A subunit. 相似文献