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31.
The present article focuses on couple types based on 2 personality traits, attachment security and neuroticism, as they relate to 2 facets of the marital relationship--a global evaluation of relationship quality and dyadic closeness-distance. The sample consisted of 248 married couples who completed measures of attachment anxiety and avoidance, neuroticism, and marital quality, as well as levels of closeness reported over 7 consecutive days. Cluster analyses yielded 3 types of dyadic attachment configurations (secure, fearful avoidant, and insecure-mixed) and 4 types of dyadic neuroticism (low couple neuroticism, high couple neuroticism, wife neuroticism, and husband neuroticism). Significant differences were found among attachment and neuroticism dyadic types in marital quality. The findings are discussed in terms of the viability of dyadic types based on individual traits, implying that attachment security yields itself to dyadic conceptualization more than neuroticism. 相似文献
32.
Health care systems operate differently in every country and are products of historical and political factors. We compared health care systems for career soldiers in various countries with those of the Israel Defense Forces. Questionnaires requesting data regarding military health care services provided in their countries were sent to military attaches serving in Israel. The countries for which data were gathered include Argentina, Brazil, Chile, China, England, France, Finland, Germany, Hungary, Israel, Poland, Romania, Spain, and the United States. In most countries, career soldiers receive better health care services than civilians, especially in countries with military rule or under military threat. 相似文献
33.
Developmental changes in GABAergic actions and seizure susceptibility in the rat hippocampus 总被引:14,自引:0,他引:14
Khazipov R Khalilov I Tyzio R Morozova E Ben-Ari Y Holmes GL 《The European journal of neuroscience》2004,19(3):590-600
The immature brain is prone to seizures but the underlying mechanisms are poorly understood. We explored the hypothesis that increased seizure susceptibility during early development is due to the excitatory action of GABA. Using noninvasive extracellular field potential and cell-attached recordings in CA3 of Sprague-Dawley rat hippocampal slices, we compared the developmental alterations in three parameters: excitatory actions of GABA, presence of the immature pattern of giant depolarizing potentials (GDPs) and severity of epileptiform activity generated by high potassium. The GABA(A) receptor agonist isoguvacine increased firing of CA3 pyramidal cells in neonatal slices while inhibiting activity in adults. A switch in the GABA(A) signalling from excitation to inhibition occurred at postnatal day (P) 13.5 +/- 0.4. Field GDPs were present in the form of spontaneous population bursts until P12.7 +/- 0.3. High potassium (8.5 mm) induced seizure-like events (SLEs) in 35% of slices at P7-16 (peak at P11.3 +/- 0.4), but only interictal activity before and after that age. The GABA(A) receptor antagonist bicuculline reduced the frequency or completely blocked SLEs and induced interictal clonic-like activity accompanied by a reduction in the frequency but an increase in the amplitude of the population spikes. In slices with interictal activity, bicuculline typically caused a large amplitude interictal clonic-like activity at all ages; in slices from P5-16 rats it was often preceded by one SLE at the beginning of bicuculline application. These results suggest that, in the immature hippocampus, GABA exerts dual (both excitatory and inhibitory) actions and that the excitatory component in the action of GABA may contribute to increased excitability during early development. 相似文献
34.
35.
Nanoscale quantum dots hold promise for cancer applications 总被引:1,自引:0,他引:1
Ben-Ari ET 《Journal of the National Cancer Institute》2003,95(7):502-504
36.
In hippocampal CA1 pyramidal neurons, GABAergic synapses are established before glutamatergic synapses. GABAergic interneurons should therefore develop and acquire synapses at an earlier stage to provide the source for GABAergic synapses. We now report that this is indeed the case. At birth and in utero, when nearly all pyramidal neurons are not yet functional, most interneurons have already either GABAergic only or GABAergic and glutamatergic postsynaptic currents. At birth, the morphological maturation of interneurons parallels their individual functional responses. In addition, the formation of functional interneurons types appears to be a sequential process. Interneurons that innervate other interneurons acquire GABA(A) synapses before peridendritic interneurons, but also before perisomatic interneurons that are not yet functional at birth. Therefore, interneurons are the source and the targets of the first synapses formed in the developing circuit. Since GABA was shown to be excitatory in utero, interneurons provide all the excitatory drive at a time when the principal cells are silent. They could therefore play a central role in the formation of the cortical circuit at early developmental stages. 相似文献
37.
Developing networks play a similar melody 总被引:32,自引:0,他引:32
Ben-Ari Y 《Trends in neurosciences》2001,24(6):353-360
During development, when synapses start to be established, a primitive form of network-driven activity provides most of the synaptic activity. This pattern enables a high degree of synchrony in immature neurons in spite of the small number of functional synapses and could participate in activity-dependent growth and synapse formation. Relying on the giant depolarizing potentials that provide most of the synaptic activity in the developing hippocampus, this article reviews the common properties and generating mechanisms of these patterns, and particularly the role of the early depolarizing action of GABA(A) and glycine receptors and the sequential expression of GABA and glutamate synapses. Patterns similar to giant depolarizing potentials have been observed in a wide range of structures and species suggesting that there is a temporal template throughout evolution that constitutes an essential step in the formation of functional networks. 相似文献
38.
BACKGROUND: Mycophenolate mofetil is used as an immunosuppressive agent in liver transplant recipients. Its active compound, mycophenolic acid, also inhibits the replication of Epstein-Barr virus and human immunodeficiency virus. Based on a study indicating the effectiveness of mycophenolate mofetil on hepatitis B virus (HBV) replication in infected human hepatocyte cells in culture, we examined the efficacy of mycophenolate mofetil in suppressing HBV replication in lamivudine-resistant liver allograft recipients with recurrent HBV infection. METHOD: The study population included four liver allograft recipients (three males, one female), median age 51 years (range 41-57 years), with recurrent HBV infection who proved to be resistant to lamivudine. All received standard maintenance immunosuppression therapy. Median pretreatment serum alanine aminotransferase level was 75 mu/L (range 39-182 mu/L) and HBV DNA level (quantitative dot blot), 70 pg/ml (range: 10-5,000 pg/ml). Mycophenolate mofetil, 1.0 g p.o. twice daily, was administered for 8 weeks, concomitant with a reduction in the maintenance corticosteroid and cyclosporine doses. RESULTS: After mycophenolate mofetil was administered, the serum alanine aminotransferase level increased in two patients, did not change in one, and decreased in one. Serum HBV DNA levels increased in three patients and decreased (nonsignficantly) in only one patient. Two patients complained of abdominal pain and nausea. CONCLUSIONS: Mycophenolate mofetil at the dosage used is not effective in suppressing HBV replication after liver transplantation. 相似文献
39.
Orit Taubman – Ben-Ari Miriam Chasson Salam Abu Sharkia Efrat Weiss 《Journal of reproductive and infant psychology》2020,38(3):340-348
ABSTRACT
Introduction
The fact that little is yet known about the possible implications of COVID-19 for pregnancy, puts pregnant women at greater risk of heightened anxiety and psychological distress. In this study, we sought to explore the psychological distress and COVID-19-related anxiety of pregnant women during the crisis. 相似文献40.
Telomerase activity in patients with transitional cell carcinoma: a preliminary study 总被引:10,自引:0,他引:10
BACKGROUND: Telomerase activity is not detectable in normal cells, and their telomers shorten until the chromosome is unable to replicate. Immortal cells have short but stable chromosomes and increased telomerase activity. Transitional cell carcinoma (TCC) has only a few useful markers of diagnostic or prognostic importance. The objective of this study was to determine whether there was a correlation between telomerase activity and the grade or stage of TCC, and whether the enzyme's activity could serve as a biochemical marker of this tumor. METHODS: The study included 29 patients with TCC. From each patient, samples of urine cells were obtained, and a cup biopsy was taken from an apparently normal area as well as from a part of the bladder tumor resected transurethrally. Control uroepithelial biopsies were taken from normal transitional cell sites from non-TCC patients. Biopsies or cells were subjected to either histologic examination or telomerase activity determination. RESULTS: Twenty-six of 29 (90%) of the tumor biopsies exhibited telomerase activity. Most of the cup biopsies were categorized as metaplastic or dysplastic, and 20 of 29 (69%) of these exhibited telomerase activity. Telomerase activity was found in 17 of 21 (81%) of the urine cells but in only 3 of 14 (21%) of control urine cells. All (10 of 10) of the uroepithelial biopsies taken from non-TCC patients did not show any telomerase activity. CONCLUSIONS: In this study, almost all tumor biopsies exhibited telomerase activity. The high incidence of telomerase activity found in cup biopsies of the malignant field uroepithelial cells from cup biopsies of TCC patients may suggest that telomerase could be activated early in carcinogenesis. A high incidence of telomerase activity was found in voided uroepithelial cells of TCC patients; however, no correlation between this activity and the histologic determination of grading and staging of the tumor was found. 相似文献