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51.
Negative beliefs about the self, self‐blame, guilt, and shame have been consistently linked to emotional problems, such as posttraumatic stress disorder and depression, following trauma exposure. To expand understanding of the potential role of negative self‐conscious cognitions and emotions in other forms of posttrauma maladjustments, such as maladaptive behaviors, the current study examined the associations between these cognitions and emotions with dissociation, alcohol use, and avoidant problem‐solving. As a secondary goal, the influence of time since trauma exposure was considered given recent data suggesting that some posttraumatic responses require lengthier time following trauma to become salient. Multiple‐group analysis was conducted in two groups of female survivors of intimate partner violence (IPV): women whose IPV experiences occurred within 3 months prior to assessment (early posttrauma phase [EPP]; n = 67) and those whose experiences occurred 12 months or more prior to assessment (chronic posttrauma phase [CPP]; n = 145). The results suggested model invariance. Posttraumatic negative self‐conscious cognitions and emotions were significantly correlated with dissociation (EPP group: β = .61, p < .001 and CPP group: β = .48, p < .001), alcohol use (EPP group: β = .31, p = .014 and CPP group: β = .30, p < .001), and avoidant problem‐solving (EPP group: β = .58, p < .001 and CPP group: β = .56, p < .001). The findings highlight the importance of negative self‐conscious cognitions and emotions in posttrauma maladjustment and support intervening in these domains shortly after trauma exposure.  相似文献   
52.
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
53.
While most women with epilepsy can expect a normal pregnancy outcome, epilepsy remains a significant contributor to both maternal and perinatal morbidity. Pre-pregnancy planning must address reliable contraception and optimisation of antiepileptic drug (AED) regimens to minimise teratogenic risk while maintaining seizure control. The most recent data from the AED registries regarding malformations is presented in this review, as is the limited data on the newer AEDs and studies linking neurocognitive outcomes to AED exposure. During pregnancy, important considerations include; therapeutic drug monitoring, surveillance for obstetric complications and vigilance for seizures during the intrapartum and postpartum period.  相似文献   
54.
Cell and tissue engineering are now being translated into clinical organ replacement, offering alternatives to fight morbidity, organ shortages and ethico-social problems associated with allotransplantation. Central to the recent first successful use of stem cells to create an organ replacement in man was our development of a bioreactor environment. Critical design features were the abilities to drive the growth of two different cell types, to support 3D maturation, to maintain biomechanical and biological properties and to provide appropriate hydrodynamic stimuli and adequate mass transport. An analytical model was developed and applied to predict oxygen profiles in the bioreactor-cultured organ construct and in the culture media, comparing representative culture configurations and operating conditions. Autologous respiratory epithelial cells and mesenchymal stem cells (BMSCs, then differentiated into chondrocytes) were isolated, characterized and expanded. Both cell types were seeded and cultured onto a decellularized human donor tracheal matrix within the bioreactor. One year post-operatively, graft and patient are healthy, and biopsies confirm angiogenesis, viable epithelial cells and chondrocytes. Our rotating double-chamber bioreactor permits the efficient repopulation of a decellularized human matrix, a concept that can be applied clinically, as demonstrated by the successful tracheal transplantation.  相似文献   
55.
Patients who have undergone allogeneic bone marrow transplantation (allo-BMT) are susceptible to a variety of opportunistic infectious complications in the months to years after engraftment. Impaired in vitro T-cell functions have been documented in these patients, and these T-cell dysfunctions contribute to the prolonged immune deficiency after allo-BMT. In the present study, we examined the expression of CD26 as well as the reconstitution of CD26-mediated T-cell costimulation via the CD3 and CD2 pathways at various times in patients aged greater than 18 years after CD6-positive, T-cell depleted allo- BMT. We found that the percentage of CD26- and CD3-positive cells, as well as the levels of expression of both antigens, was lower than in normal controls during the first 4 months after CD6-depleted allo-BMT. Subsequently, the amount of lymphocytes expressing CD3 and CD26 and the quantitative surface expression of CD3 and CD26 were not significantly different in patients and normal controls. Functional studies showed that CD26-mediated T-cell proliferation via the CD3 pathway was considerably improved and almost reached normal levels by 1 year, whereas recovery of CD26-mediated T-cell proliferation via the CD2 pathway was delayed for at least 2 years after CD6-depleted allo-BMT. As CD26 involvement in the regulation of human thymocyte activation is restricted preferentially to the CD3 pathway--unlike its involvement with both CD3 and CD2 pathways of peripheral T cells--our results suggest that the different effects of CD26-mediated costimulation via the CD3 and CD2 pathways after CD6-depleted allo-BMT may be a reflection of peripheral T-cell immaturity in those individuals, similar to that seen in mature medullary thymocytes or cord T lymphocytes.  相似文献   
56.
Intratympanic perfusion for the treatment of tinnitus   总被引:3,自引:0,他引:3  
Intratympanic treatment of tinnitus with corticosteroids or gentamicin should be considered as an option of treatment in selected tinnitus patients, alone or in combination with standard modalities of management such as tinnitus retraining therapy, masking, and hearing aid amplification. Review of the literature and the authors' experience suggest the following points regarding intratympanic treatment for tinnitus: 1. Lidocaine, although effective in decreasing tinnitus, has been largely abandoned because of its severe side-effect profile and need for inpatient administration. 2. Corticosteroids have been associated with few if any side effects. 3. The good results reported in the literature with intratympanic steroids for treating tinnitus of various causes should be viewed with caution,because most are retrospective and uncontrolled studies. 4. Some Meniere's disease patients with tinnitus may experience tinnitus improvement following intratympanic steroids. This treatment may be considered in such patients, especially for those with good hearing. 5. Gentamicin is effective in eliminating or reducing tinnitus in a significant number of patients with Meniere's disease and may be considered especially for those with nonserviceable hearing. 6. Further prospective, randomized, and controlled studies to evaluate the effect of intratympanic perfusion for the treatment of tinnitus are warranted.  相似文献   
57.
患者为1例39岁女性,患T/NK细胞淋巴瘤,在外周血异基因干细胞移植后15天,发生环孢素A(CSA)毒性相关的微血管病溶血性贫血(MAHA).因血清肌酐从移植前的0.4mg/dL,上升至移植后第9和15天的1.0和2.9 mg/dL.故停用CSA.  相似文献   
58.
Smythe  JS; Spring  FA; Gardner  B; Parsons  SF; Judson  PA; Anstee  DJ 《Blood》1995,85(10):2929-2936
This report describes the production and characterization of 13 rodent monoclonal antibodies to the human erythrocyte anion transport protein AE1 (syn. band 3). Eleven antibodies (4 murine and 7 rat) recognize epitopes dependent on the integrity of the third extracellular loop of the protein. Two antibodies (1 murine and 1 rat) recognize epitopes on the N-terminal cytoplasmic domain. Quantitative binding studies using radioiodinated IgG and Fab fragments of antibodies to extracellular epitopes on AE1 ranged from 77,000 to 313,000 (IgG) and from 241,000 to 772,000 (Fab) molecules bound at saturation. The results indicate that the epitopes recognized by different antibodies vary in their accessibility and suggest that there is heterogeneity in the organization of individual AE1 molecules in the red blood cell membrane. Quantitative binding studies on South East Asian ovalocytes using several antibodies to AE1 and an anti-Wrb show a marked reduction in the number of antibody molecules bound at saturation. These results are consistent with the existence of highly cooperative interactions between transmembrane domains of AE1 in normal erythrocytes and the disruption of these interactions in the variant AE1 found in South East Asian ovalocytes.  相似文献   
59.
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process.  相似文献   
60.
Empirical therapy for subfertility using assisted reproductive technologies recently has gained popularity; however, the cost-effectiveness of these therapies, compared with an untreated control group, has not been established. Similarly, there has been no comparative cost analysis of the utility of controlled ovarian hyperstimulation and IUI in the management of the same condition. Significant PRs in untreated couples with subfertility mandate the design and execution of controlled trials to ascertain the role of controlled ovarian hyperstimulation and IUI in infertility therapy. Various disorders of subfertility have been treated with controlled ovarian hyperstimulation and IUI. The rationale for this therapy is the increase in gamete density at the site of fertilization, as with GIFT and IVF when used for management of the same problems. The live birth rate per initiated cycle and risk of complications are similar to results recently reported for GIFT and IVF. The utility of controlled ovarian hyperstimulation and IUI still remains controversial. When the relatively low direct and indirect costs of controlled ovarian hyperstimulation and IUI are considered, acknowledging the lack of prospective, controlled studies, this procedure appears to be at least as cost-effective as GIFT and IVF.  相似文献   
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