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941.
942.
BACKGROUND: On SDS-PAGE grass pollen group-5 allergens migrate as a doublet with an apparent molecular mass (M(r)) of 25 kDa. Immunoblot analysis revealed additional group 5 reactivity at double and half this M(r). The aim of this study was to investigate these group 5 molecular entities and to compare their allergenicity and behavior in quantitative immunoassays. METHODS: Group-5-specific monoclonal antibodies were produced and used for the development of a group-5-specific sandwich ELISA. Affinity-purified Dac g 5 was separated by SDS-PAGE/Western blotting; individual bands were analyzed by N-terminal sequencing. Size exclusion chromatography (SEC) in conjunction with group-5-specific ELISA, competitive RIA and RAST inhibition were used to analyze the size distribution of Dac g 5. Basophil histamine release assays were used to assess biological activity. RESULTS: The lower band of the typical group 5 doublet was identified as a truncated form lacking the typical group 5 N-terminus AD(L)/(A)GY, observed in the upper band. The 12-kDa peptide was shown to be the C-terminal half of Dac g 5 (amino acid 127 onwards). SEC in conjunction with competitive RIA revealed that around 45% of Dac g 5 is represented by the 12-kDa peptide. Both the C-terminal half and the whole allergen dimerize under nondenaturing conditions. In competitive RIA and RAST inhibition both forms are equally well detected. In contrast, the half molecule is poorly recognized in sandwich ELISA and displays negligible biological activity in basophil histamine release tests with purified IgE. CONCLUSIONS: These observations stress the need to evaluate the performance of allergen standardization protocols in detail, with special attention to allergen size distribution.  相似文献   
943.
Oral administration of solid dosage forms is usually preferred in drug therapy. Conventional imaging methods are essential tools to investigate the in vivo performance of these formulations. The non-invasive technique of ac biosusceptometry has been introduced as an alternative in studies focusing on gastrointestinal motility and, more recently, to evaluate the behaviour of magnetic tablets in vivo. The aim of this work was to employ a multisensor ac biosusceptometer system to obtain magnetic images of disintegration of tablets in vitro and in the human stomach. The results showed that the transition between the magnetic marker and the magnetic tracer characterized the onset of disintegration (t(50)) and occurred in a short time interval (1.1 +/- 0.4 min). The multisensor ac biosusceptometer was reliable to monitor and analyse the in vivo performance of magnetic tablets showing accuracy to quantify disintegration through the magnetic images and to characterize the profile of this process.  相似文献   
944.
BACKGROUND: Magnetic resonance imaging (MRI) studies have especially reported smaller hippocampal volume in patients with post-traumatic stress disorder (PTSD), most of them war or sexual abuse victims. The present study compares the hippocampal volumes of out-patients with PTSD who had low co-morbidity rates to those of trauma-exposed control subjects without PTSD, and measures hippocampal volume changes in these patients after brief eclectic psychotherapy. We hypothesized that smaller hippocampal volumes are specific to PTSD and that hippocampal volume changes after effective psychotherapy would be measurable. METHOD: Eighteen patients with PTSD and 14 traumatized control subjects were examined with MRI. In a randomized clinical trial, the PTSD patients were assigned to treatment (n = 9) or waiting-list group (n = 9). After the former received psychotherapy for 4 months, the MRI was repeated on both PTSD groups. Three temporal lobe structures were manually segmented: hippocampus, amygdala, and parahippocampal gyrus. Volumetric analysis was used to measure grey matter, white matter, and cerebrospinal fluid. RESULTS: PTSD patients had significantly smaller hippocampal volumes at baseline (total 13.8%, right 13.5%, left 14.1%) compared to the control subjects. After effective psychotherapy, however, no volume changes were found in the smaller hippocampi. CONCLUSIONS: We confirmed previous findings of smaller hippocampal volume in PTSD in a new population made up of out-patients who experienced different types of traumas, reducing co-morbidity to a minimum. Smaller hippocampal volumes did not change after effective psychotherapy, even while symptoms resolved.  相似文献   
945.
OBJECTIVE: This study examined the impact of patient characteristics and source of care on differences between whites and Latinos in use and quality of depression treatment in managed primary care settings. METHODS: Data were examined for 1,175 patients (398 Latinos and 777 whites) in 46 managed primary care practices who screened positive for probable depressive disorder. Patient baseline assessments were used to compile sociodemographic and clinical characteristics and to derive variables for receipt of any depression care and depression care that met minimum guidelines (antidepressant use or specialty counseling) in the past six months. Clinics were classified by the percentage of their patient population that consisted of Latinos to determine whether patients in highly Latino clinics reported lower rates of care. Predictors of use and quality of depression care were examined by using logistic regression. RESULTS: Rates of receipt of any depression care and guideline-level depression care were low, and Latinos were less than half as likely as whites to receive such care, even after the analyses controlled for independent predictors (that is, younger age, higher educational level, current unemployment, more comorbid medical illness, and a diagnosis of a depressive or anxiety disorder). The likelihood of receiving any care or care that met guidelines did not significantly vary according to whether clinics served a low, moderate, or high percentage of Latinos. CONCLUSIONS: Disparities in depression care for Latinos were not attributable to sociodemographic and clinical characteristics, and they were not attributable to receiving care in clinics that served ethnically similar or dissimilar clientele. These findings suggest that other patient or provider factors may be responsible.  相似文献   
946.
Xanthogranulomas of the choroids plexus (XG) are benign tumours of debatable etiology which become rarely symptomatic. Only few cases have been studied with MRI. A new case of xanthogranuloma of the third ventricle showing unusual features in the CT and MRI studies in a 47-year-old man with a 2-month history of gait and urinary disturbances and cognitive impairment is reported. The literature concerning clinical and neuroradiological presentation of intracranial xanthogranulomas is reviewed.  相似文献   
947.
The case of a 68 year-old man who developed a fatal intracranial hemorrhagic complication following percutaneous compression of the gasserian ganglion for trigeminal neuralgia is reported. The complication was likely related to improper placement of the Fogarty catheter into the temporal fossa out of the Meckel's cave. The anatomical structures at risk of damage by misplaced needle or catheter and some relevant technical details aimed to prevent extratrigeminal complications related with this and other percutaneous trigeminal lesioning procedures are analyzed.  相似文献   
948.
949.
AIM: Prevalences of overweight in The Netherlands, defined by international cut-off points, are presented in 14 500 children of Dutch origin, 2904 of Turkish and 2855 of Moroccan origin, aged 0-21 y. RESULTS: The mean prevalence for Turkish boys and girls was 23.4% and 30.2%, for Moroccans 15.8% and 24.5%, for Dutch youths in large cities 12.6% and 16.5%, and for other Dutch participants 8.7% and 11.3%, respectively. CONCLUSION: The development of adequate prevention strategies is urgently needed.  相似文献   
950.
The authors report on 2 boys, 11(1/2) and 13 years old, who received allogeneic stem cell transplantation (alloSCT) from their HLA-identical sibling after relapse of stage IV alveolar rhabdomyosarcoma. Both patients were transplanted in a non-remission status. After alloSCT both patients experienced disease progression at the primary tumor location sites and died due to the underlying disease 146 and 379 days after transplantation. The authors conclude that an alloSCT derived graft versus tumor effect might not be effective enough to overcome alveolar rhabdomyosarcoma when transplantation is carried out in a nonremission status.  相似文献   
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