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11.
The ramifications of attachment processes in adulthood at the societal level are explored, specifically, why and under what circumstances followers form attachment relationships with a leader, and how the variability in these relationships can reflect the followers' internal working models of attachment. It is argued that in crisis situations, individuals tend to form affectional bonds with (mostly charismatic) leaders that function in many respects like an attachment relationship between a child and a parent. Relations between individuals and various social institutions, such as community or state, are likewise portrayed as involving attachment dynamics. The provision of security and protection (the safe haven and the secure base functions) by social structures, institutions, and leaders is seen as needed because of the inherent perceived imperfection and fallibility of "regular" attachment figures in adulthood (e.g., parents, friends, and romantic partners). This reliance on leaders and social institutions is seen as reflecting the normative diversification in attachment dynamics that takes place with development. Cultural and individual variations in these processes are also considered.  相似文献   
12.
This study investigated the relationship between religiosity and levels of secondary traumatic stress in Israeli-Jewish body handlers. The Impact of Event Scale (IES), the General Health Questionnaire, 12 Items (GHQ-12), and a prior exposure severity tool were used to assess secondary traumatic stress symptoms in 63 ultraorthodox male body handlers as they compared to 86 secular forensic identification technicians from the Israeli police. Excluding possible confounders of age and number of years at the job, there was no significant difference between the religious and nonreligious groups on the intrusion and avoidance scores, whereas the GHQ-12 scores were significantly higher among the religious group. Religiosity did not seem to have a salutary effect on secondary traumatic stress in this cohort.  相似文献   
13.
Semaphorin-3F is an inhibitor of tumor angiogenesis   总被引:15,自引:0,他引:15  
The neuropilin-1 (np1) and neuropilin-2 (np2) receptors form complexes with type-A plexins. These complexes serve as signaling receptors for specific class-3 semaphorins. Np1 and np2 function in addition as receptors for heparin-binding forms of vascular endothelial growth factor (VEGF), such as VEGF(165). Human umbilical vein endothelial cells (HUVEC) express tyrosine-kinase receptors for VEGF and basic fibroblast growth factor (bFGF), as well as np1, np2, and several type-A plexins. We have found that semaphorin-3F (s3f), a semaphorin which signals through the np2 receptor, was able to inhibit VEGF(165), as well as bFGF-induced proliferation of HUVECs. Furthermore, s3f inhibited VEGF as well as bFGF-induced phosphorylation of extracellular signal-regulated kinase-1/2. Our experiments indicate that bFGF does not bind to neuropilins, nor does s3f inhibit the binding of bFGF to FGF receptors. It is therefore possible that s3f inhibits the activity of bFGF by a mechanism that requires active s3f signal transduction rather than by inhibition of bFGF binding to FGF receptors. s3f also inhibited VEGF(165), as well as bFGF-induced in vivo angiogenesis as determined by the alginate micro-encapsulation and Matrigel plug assays. Overexpression of s3f in tumorigenic human HEK293 cells inhibited their tumor-forming ability but not their proliferation in cell culture. The tumors that did develop from s3f-expressing HEK293 cells developed at a much slower rate and had a significantly lower concentration of tumor-associated blood vessels, indicating that s3f is an inhibitor of tumor angiogenesis.  相似文献   
14.
15.
Lubetzky O  Gilat I 《Death Studies》2002,26(7):523-543
The differences between adolescents born pre-term (n = 50) and a matched sample of adolescents born full-term were examined in relation to fear of personal death, attachment styles, and the relation between the two variables. Findings revealed that adolescents born pre-term showed a higher level of fear of personal death and a lower frequency of secure attachment style than adolescents born full-term. In addition, secure full-term born adolescents exhibited a lower level of fear of personal death compared with insecure adolescents; whereas among those born pre-term, attachment styles did not affect the level of fear of personal death. Results are discussed in terms of the long-term impact of premature birth on affect regulation in adolescence.  相似文献   
16.
We examined kinetic and dynamic factors to determine the pharmacological and behavioral safety and tolerability of low versus high doses of an opiate antagonist, naltrexone (50 mg/day vs. 100 mg/day), and acamprosate (2 g/day vs. 3 g/day), a functional N-methyl-D-aspartate receptor antagonist, both independently and combined, among non-treatment-seeking, alcohol-dependent individuals. This double-blind, double-dummy, placebo-controlled, randomized, 23-day, four-way crossover study involved 23 subjects assigned to one of four groups. Placebo washout (phase I) preceded phase II, where subjects received low-dose or high-dose naltrexone or acamprosate. In phases III and IV, the alternative medication type at its lower and higher doses, respectively, was administered with continuation of the phase II medication. Predetermined behavioral, performance, and pharmacological criteria determined significant pathological change from baseline (phase I). Case records were reviewed. Criterion-significant increases in symptoms from baseline with monotherapy included nervousness and fatigue with 3 g acamprosate and somnolence and headache with 50 mg and 100 mg naltrexone, respectively. Combined treatment at various doses evinced anger, depression, somnolence, nervousness, diarrhea, and headache. Notably, for all but one subject who dropped out, increased symptoms did not produce any remarkable clinical deterioration. Naltrexone administration significantly increased plasma acetylhomotaurine (i.e., acamprosate) levels, presumably by prolonging gastric emptying. The level of neither plasma acetylhomotaurine nor plasma 6-beta naltrexol (i.e., naltrexone's metabolite) predicted adverse-event frequency. Naltrexone and acamprosate, both alone and in combination at the tested doses, were behaviorally and pharmacologically safe. Adverse events were infrequent, were of moderate intensity, and resolved with reassurance and symptomatic treatment. More side effects were noted with the combination of medications than with either medication alone. Naltrexone administration significantly increased plasma acamprosate levels.  相似文献   
17.
Transplanted neural precursor cells remyelinate efficiently acutely demyelinated focal lesions. However, the clinical value of cell transplantation in a chronic, multifocal disease like multiple sclerosis will depend on the ability of transplanted cells to migrate to the multiple disease foci in the brain. Here, we expanded newborn rat neural precursor cells in spheres and transplanted them intracerebroventricularly or intrathecally in rats. The cells were labeled by the nuclear fluorescent dye Hoechst or by incubation with BrdU to enable their identification at 2 days and 2 weeks after transplantation, respectively. Spheres consisted of PSA-NCAM(+), nestin(+), NG2(-) undifferentiated precursor cells that differentiated in vitro into astrocytes, oligodendrocytes, and neurons. Spheres that were transplanted into intact rats remained mostly in the ventricles or in the spinal subarachnoid space. Following transplantation at peak of experimental autoimmune encephalomyelitis, cells migrated into the brain or spinal cord parenchyma, exclusively into inflamed white matter but not into adjacent gray matter regions. After 2 weeks, many transplanted cells had migrated into distant white matter tracts and acquired specific markers of the astroglial and oligodendroglial lineages. Thus, the inflammatory process may attract targeted migration of transplanted precursor cells into the brain parenchyma.  相似文献   
18.
The Human MHC Project aims at comprehensive cataloging of peptides presented within the context of different human leukocyte antigens (HLA) expressed by cells of various tissue origins, both in health and in disease. Of major interest are peptides presented on cancer cells, which include peptides derived from tumor antigens that are of interest for immunotherapy. Here, HLA-restricted tumor-specific antigens were identified by transfecting human breast, ovarian and prostate tumor cell lines with truncated genes of HLA-A2 and HLA-B7. Soluble HLA secreted by these cell lines were purified by affinity chromatography and analyzed by nano-capillary electrospray ionization-tandem mass spectrometry. Typically, a large peptide pool was recovered and sequenced including peptides derived from MAGE-B2 and mucin and other new tumor-derived antigens that may serve as potential candidates for immunotherapy.  相似文献   
19.
Medicine today offers no cure for patients suffering from mitochondrial disorders, such as lipoamide dehydrogenase (LAD; also known as E3) deficiency, and treatment is limited to symptomatic care. LAD is one of the components of the α-ketoacid dehydrogenase complexes, which are mitochondrial multienzyme complexes crucial for the metabolism of carbohydrates and amino acids. Recently, we tested the therapeutic approach for treating mitochondrial disorders whereby the activity of multicomponent complexes in the mitochondria is restored by TAT-mediated enzyme replacement therapy (ERT). The LAD deficiency disease was used before as a proof-of-principle in vitro, in patients' cells, utilizing the TAT-LAD fusion protein. In this report, we present successful TAT-mediated ERT in an in vivo mouse model using E3-deficient mice. We demonstrate the delivery of TAT-LAD into E3-deficient mice tissues and that a single administration of TAT-LAD results in a significant increase in the enzymatic activity of the mitochondrial multienzyme complex pyruvate dehydrogenase complex within the liver, heart and, most importantly, the brain of TAT-LAD-treated E3-deficient mice. We believe that this TAT-mediated ERT approach could change the management of mitochondrial disorders and of other metabolic diseases in modern medicine.  相似文献   
20.
Background Leukocytoclastic vasculitis (LV) is characterized by segmental inflammation of small blood vessels, resulting in ischemic damage to the surrounding tissue. It is considered to be related to a type III hypersensitivity reaction, although the exact etiologic mechanism is not clear. Objective The purpose of this study was to evaluate neutrophil functions in patients with LV in order to understand their role in the pathogenesis of the disease. Methods Neutrophil functions were examined in 25 LV patients. The patients were divided into two groups: Group A consisted of 14 patients with drug-induced LV and Group B consisted of 11 patients where LV was induced by other factors. Results Both groups of patients showed significantly reduced chemotaxis and phagocytosis. Superoxide generation was significantly lower (P < 0.001) only in neutrophils from patients in Group A: 5.8 ± 0.5 nmoles O2/106 cells/min compared to 9.08 ± 0.8 nmoles O2/106 cells/min in the controls. Preincubation on normal neutrophils with the patients' sera caused an increase in their superoxide generation in accordance with the high IL-8 levels in these sera. Conclusions Neutrophil functions were significantly impaired in patients with LV. It is likely that factors present in LV plasma may chronically activate neutrophils, so that they become refracfory to further stimulation. Our study showed that neutrophil superoxide generation is low only in drug-induced LV; this test may assist in distinguishing such patients from those with LV induced by other causes.  相似文献   
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