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1.
ABSTRACT

Introduction

Individuals with autism spectrum disorder (ASD) and intellectual disability (ID) seem to be at increased risk for post-traumatic stress disorder (PTSD), but knowledge is sparse regarding its identification in this population. Previous research indicates that certain symptoms of PTSD may be more easily recognized, and that identifying reexperiencing and avoidance is particularly challenging.  相似文献   
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To obtain more information on the biochemical background, of methyl mercury (MeHg) and triethyl lead (Et3Pb) toxicity, the doses which were needed to alter the cellular content of adenine nucleotides were compared to doses which induced morphological alterations. Three-week-old cultures of brain cells from new-born rat were incubated for 5-60 min. with 28, 16, and 8 X 10(-6) M MeHg or with 3 X 10(-6) M Et3Pb in the nutrition medium. MeHg at 28 and 16 X 10(-6) M simultaneously changed the cell shape and reduced both the cellular content of adenine nucleotides and the relative level of ATP. In cells treated with 16 X 10(-6) M MeHg, a cellular increase in inosine and hypoxanthine and an unaltered content of adenine nucleotides in the nutrition medium, points to an intracellular degradation of adenine nucleotides. Incubation with 8 X 10(-6) M MeHg during the first hour of incubation, did not change the content of adenine nucleotides, however, MeHg induced a slowly progressing degeneration of cellular extensions. 3 X 10(-6) M Et3Pb induced morphological alterations but no changes in cellular nucleotide levels. The results show that morphological alterations occur in MeHg and Et3Pb treated cultures at concentrations of the compounds which are too low to change the content and composition of cellular adenine nucleotides.  相似文献   
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The β‐adhesin part of the Porphyromonas gingivalis W50 (ATCC 53978) protease HRgpA was cloned in an eukaryotic expression vector and expressed in COS‐7 cells. The monoclonal antibody MAb (61BG1.3), specific for the hemagglutinating domain of β‐adhesin, recognized the expressed β‐adhesin in the transfected cells both by immunoblot and immunofluorescence. Sprague Dawley rats were immunized intramuscularly with β‐adhesin encoding expression plasmid and expression plasmid without β‐adhesin insert. Skeletal muscle tissue at the site of immunization in the β‐adhesin immunized animals was shown to express this protein. The immunization induced a β‐adhesin‐specific antibody response. Sera from the immunized animals were tested for hemagglutination inhibiting activity. Due to high natural inhibiting activity in all rat sera tested, no increased hemagglutination inhibition was detected in sera from the β‐adhesin immunized animals.  相似文献   
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OBJECTIVES: To test a possible association between the educational level (EL), cognitive performance, and neuropsychiatric features in Parkinson disease (PD). BACKGROUND: An inverse association has been reported between EL and cognitive dysfunction in patients with senile dementia of Alzheimer type but it is yet unsettled whether education has a similar effect on cognition in PD. METHODS: Seventy-two PD patients (45 males, mean age 68.7+/-11.6 y) underwent a detailed neurologic examination, a battery of neuropsychologic tests, and questionnaires for the evaluation of psychosis, sleep disturbances, and depression. According to the number of educational years, patients were divided into 3 groups: low EL (0 to 8 y), (15 patients), intermediate EL (9 to 12 y) (28 patients), and high EL (>/=13 y) (29 patients). RESULTS: Patients with a higher EL had a better cognitive function and an association was found between the patients' EL and their scores in various neuropsychologic tests mainly those sensitive to frontal lobe dysfunction. Low education was associated with an increased risk for hallucinations and a trend for more depression, delusions, and sleep disturbances. CONCLUSIONS: The association between high educational attainment and the lower risk of cognitive dysfunction suggest that education might modulate cognitive performance in PD.  相似文献   
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Cerebellar involvement in motor and non-motor sequence learning was examined with serial reaction time tasks (SRT). Our sample consisted of 8 children and adolescents who had undergone surgical removal of a benign posterior fossa tumor (PFT) during childhood. None of them had undergone chemotherapy or cranial radiation therapy (CRT). Ages ranged from 1-11 years at surgery and 9-17 years at testing. The children were tested not earlier than 2.5 years after surgery (M = 5.9 years), enabling brain plasticity and recovery of functions. Their performance was compared with a matched control sample. The PFT group was not impaired in the implicit learning of sequences, as reflected in their performance in blocks with a repeated sequence, both before and after a random block. However, in the perceptual task, their performance deteriorated more than that of the control group when a random block was introduced, suggesting that it was more difficult for the patients to respond flexibly or change their response set when encountering changing task demands. These results are in line with another study by our group on task switching with the same patients.  相似文献   
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Background: Myocardial protection during open heart surgery is based on administration of oxygenated blood cardioplegia, the preferred temperature of which is still under debate. The current randomized study was designed to prospectively evaluate the quality of myocardial protection and the functional recovery of the heart with either normothermic (group N) or hypothermic (group H) oxygenated blood cardioplegia.

Methods: Under continuous electrocardiographic Holter monitoring, 42 patients were randomly scheduled to receive either normothermic (33.5 degrees C) or hypothermic (10 degrees C) cardioplegia solutions during coronary bypass grafting surgery. Blood samples for creatinine phosphokinase, creatinine phosphokinase-MB, lactate, epinephrine, and norepinephrine were withdrawn during cardiopulmonary bypass via a coronary sinus cannula.

Results: Active cooling in group H on initiation of cardio-pulmonary bypass was characterized by transition through ventricular fibrillation in 75% of patients, whereas in group N atrial fibrillation occurred in 65% of patients. On myocardial reperfusion, sinus rhythm spontaneously resumed in 95% of group N patients compared to 25% in group H (P = 0.0003). In the latter, 75% of patients developed ventricular fibrillation often followed by complete atrioventricular block, which necessitated temporary pacing for a mean duration of 168+/-32 min. Both groups showed a similar incidence of intraventricular block and ST segment changes. However, the incidence of ventricular premature beats in the first 16 h after cardiopulmonary bypass was significantly greater in group H (P < 0.05), 20 +/-26/h, compared to 3+/-5/h in group N. Blood concentrations of lactate, creatinine phosphokinase, epinephrine, and norepinephrine increased gradually during the operation, but the differences between the groups were not significant.  相似文献   

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Subjects with central field loss (CFL) individually selected enhancement parameters to improve visibility of static video images. The effect of enhancement on performance and on perceived quality of motion video was assessed. Performance, e.g. recognition of visual details, was assessed by having subjects answer questions regarding visual information contained in the video motion segments that were enhanced using the individually-selected parameters. Enhancement did not improve subject performance on questions about video content. This result might be due to a ceiling effect limitation of the performance assessment method. In a second procedure, subjects' continuous perceptions of quality (using an adjective-based rating scale) were made while the enhancement parameters were abruptly switched among multiple values; these included the individually-selected enhancements, as well as unenhanced, over-enhanced, and degraded segments. The results indicate that adaptive enhancement (individually-tuned using a static image) adds significantly to perceived image quality when viewing motion video. Subjects who selected stronger contrast enhancement also perceived the enhancement to provide a larger benefit in image quality.  相似文献   
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The pattern of infection inGlossina morsitans morsitans andG. m. centralis membrane-fed on eland, buffalo or goat blood mixed withTrypanosoma congolense orT. brucei was studied from day 1 to day 10. Tsetse were initially permissive vectors, with most flies harbouring infections of 104–105 parasites on day 3. However, after a second blood meal on day 3, flies cleared many infections withG. m. morsitans clearing more infections thanG. m. centralis. Infective feeds of goat blood consistently increased final infection rates by limiting the number of infections lost between days 3 and 6. In further experiments withG. m. morsitans only, this effect was replicated by feeding flies on erythrocytes but not on serum. These results suggest that compounds from some mammalian erythrocytes match the target specificity ofG. m. morsitans midgut lectins and, hence, have a protective effect on trypanosome establishment in the fly.  相似文献   
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