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921.
OBJECTIVE: Bilateral temporal hypoperfusion at rest was recently described in autism. In normal adults, these regions are activated by listening to speech-like sounds. To investigate auditory cortical processing in autism, the authors performed a positron emission tomography activation study. METHOD: Regional cerebral blood flow was measured in five autistic adults and eight comparison subjects during rest and while listening to speech-like sounds. RESULTS: Similar to the comparison subjects, autistic patients showed a bilateral activation of the superior temporal gyrus. However, an abnormal pattern of hemispheric activation was observed in the autistic group. The volume of activation was larger on the right side in the autistic patients, whereas the reverse pattern was found in the comparison group. The direct comparison between the two groups showed that the right middle frontal gyrus exhibited significantly greater activation in the autistic group. Conversely, the left temporal areas exhibited less activation in autistic patients. CONCLUSIONS: These findings suggest that abnormal auditory cortical processing is implicated in the language impairments and the inadequate response to sounds typically seen in autism.  相似文献   
922.
Autosomal dominant GH deficiency type II (IGHDII) is often associated with mutations in the human GH gene (GH1) that give rise to products lacking exon-3 ((Deltaexon3)hGH). In the heterozygous state, these act as dominant negative mutations that prevent the release of human pituitary GH (hGH). To determine the mechanisms of these dominant negative effects, we used a combination of transgenic and morphological approaches in both in vitro and in vivo models. Rat GC cell lines were generated expressing either wild-type GH1 (WT-hGH-GC) or a genomic GH1 sequence containing a G->A transition at the donor splice site of IVS3 ((Deltaexon3)hGH-GC). WT-hGH-GC cells grew normally and produced equivalent amounts of human and rGH packaged in dense-cored secretory vesicles (SVs). In contrast, (Deltaexon3)hGH-GC cells showed few SVs but accumulated secretory product in amorphous cytoplasmic aggregates. They produced much less rGH and grew more slowly than WT-hGH-GC cells. When cotransfected with an enhanced green fluorescent protein construct (GH-eGFP), which copackages with GH in SVs, WT-hGH-GC cells showed normal electron microscopy morphology and SV movements, tracked with total internal reflectance fluorescence microscopy. In contrast, coexpression of (Deltaexon3)hGH with GH-eGFP abolished the vesicular targeting of GH-eGFP, which instead accumulated in static aggregates. Transgenic mice expressing (Deltaexon3)hGH in somatotrophs showed an IGHD-II phenotype with mild to severe pituitary hypoplasia and dwarfism, evident at weaning in the most severely affected lines. Hypothalamic GHRH expression was up-regulated and somatostatin expression reduced in (Deltaexon3)hGH transgenic mice, consistent with their profound GHD. Few SVs were detectable in the residual pituitary somatotrophs in (Deltaexon3)hGH transgenic mice, and these cells showed grossly abnormal morphology. A low copy number transgenic line showed a mild effect relatively specific for GH, whereas two severely affected lines with higher transgene copy numbers showed early onset, widespread pituitary damage, macrophage invasion, and multiple hormone deficiencies. These new in vitro and in vivo models shed new light on the cellular mechanisms involved in IGHDII, as well as its phenotypic consequences in vivo.  相似文献   
923.
TD-6424, a rapidly bactericidal agent with multiple mechanisms of action, is more potent in vitro and more rapidly bactericidal than currently available agents against methicillin-susceptible and methicillin-resistant Staphylococcus aureus. TD-6424 produces a postantibiotic effect with a duration of 4 to 6 h against these organisms. The results suggest potential efficacy against susceptible and resistant strains of S. aureus.  相似文献   
924.
To our knowledge new-onset psychotic symptoms have not been reported in connection with the September 11, 2001 terrorist attacks on the World Trade Center and the Pentagon. We describe two cases of brief psychotic disorder in adults who experienced the terrorist attacks from afar through television coverage. The patients were brought in for assessment to a medical center in the northeastern United States approximately 2 weeks after the attacks on September 11. We discuss the role of television coverage of stressful events in the induction of psychotic symptoms.  相似文献   
925.
Pace A 《Injury》2003,34(9):693-698
In this article we analyse the Italian Trauma System, stressing what has been modified over the last decade, in order to provide a more adequate and safe pre-hospital care, as well as a more efficient in-hospital treatment. We describe how the 118 operative exchange is organised, the most important educational courses for the health personnel and the new emergency/urgency structures called DEA.  相似文献   
926.
927.
Many epidemiological studies on Buruli ulcer have established the endemic zones in the Congolese Democratic Republic. But the situation about the areas where the refugees are located in high endemicity zones has not yet been studied. The present study describes the presence of the Mycobacterium ulcerans infection in the angolese refugee populationat Kimpese. The data obtained reveal that 50% of patients in the region are angolese refugees. All patients were infected two years before their insertion. The group most affected are children under 15 with a predominance of masculine patients. The legs were the most affected. The most frequent form is the ulcerative form.  相似文献   
928.
Foot,hand, face and eye representation in the human striatum   总被引:4,自引:4,他引:0  
The present study aimed at determining the three-dimensional organization of striatal activation during foot, hand, face and eye movements. Seven right-handed, healthy volunteers were studied at 1.5 T using blood oxygen level dependent (BOLD) contrast. The tasks consisted of self-paced flexion/extension of the right and left fingers and right toes, contraction of the lips and saccadic eye movements. For foot, hand and face movements, striatal activation was mainly found in the putamen with a somatotopical organization, the foot area being dorsal, the face area more ventral and medial, the hand area in between. Overlap between somatotopic territories was present, more prominent for hand-face than for foot-face or foot-hand areas. In the putamen, the activated areas of the ipsi- and contralateral hand areas were not identical, suggesting a partial segregation of the ipsi- and contralateral striatal sensorimotor projections. For saccadic eye movements, bilateral activation was observed at the junction between the body and the head of the caudate nucleus and in the right putamen. These data present evidence for a somatotopic organization of the human striatum which corresponds with the topography of corticostriatal projections described in the non-human primates.  相似文献   
929.
930.
We report a case of cerebral arterial air embolism that was followed by a brain computed tomographic scan and magnetic resonance imaging during the first week after onset. A 73-year-old man was admitted for treatment of pleural dissemination that was a recurrence after right lower bilectomy for advanced lung cancer. Thirty minutes after an anti-drug administration through the chest drainage tube, he lost consciousness shortly after coughing. A bubble in the inferior sagittal sinus was observed on the day of the stroke, which then disappeared within 24 hours. It seems that the anti-cancer agent evoked inflammation at the visceral pleura and the subject inhaled massive air flow into the systemic circulation.  相似文献   
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