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81.
BACKGROUND: Functional MRI studies have begun to identify neural networks implicated in visuo-spatial working memory in healthy volunteers and patients with schizophrenia. The study of schizotypal personality disorder (SPD) provides regional analysis in unmedicated patients in the schizophrenia spectrum. METHOD: Unmedicated patients with SPD by DSM-IV criteria and normal controls were assessed with fMRI while performing a visuo-spatial working-memory task. It required the subjects to retain the location of three dots located on the circumference of an imaginary circle and then respond to a query display in which one dot was presented and the subject required to press a button to indicate whether the probe dot location was previously displayed. Subject groups did not differ significantly in spatial memory scores. The exact Talairach and Tournoux coordinates of brain areas previously reported to show activation with spatial memory tasks were assessed. RESULTS: The majority of these locations showed BOLD response activation significantly less in patients during the memory retention period, including the left ventral prefrontal cortex, superior frontal gyrus, intraparietal cortex and posterior inferior gyrus. Regions in the right middle prefrontal and prestriate cortex showed greater activation at a trend level for patients with SPD than for normal controls. In addition, we replicated the findings of increased activation with the task in healthy volunteers in the premotor areas, ventral prefrontal cortex and parietal cortex. CONCLUSIONS: SPD patients show decreased activation compared to healthy volunteers in key frontal regions and we also provided a partial replication of findings reported in healthy subjects.  相似文献   
82.
BACKGROUND: Cupressaceae is a family of plants resistant to airborne contamination, and its pollen is the main cause of winter allergic respiratory diseases, especially in North America, Japan, and Mediterranean countries. Recently, a major allergen from Cupressus arizonica pollen grains, Cup a 3, was cloned and expressed. OBJECTIVE: To study the effects of air pollution on the expression of Cup a 3, a thaumatinlike protein, in C. arizonica pollen grains using a combination of transmission electron microscopy and immunocytochemical techniques. METHODS: Observations were made in mature and hydrated C. arizonica pollen grains from various regions in Spain with different degrees of air pollution. Specimens were fixed using freezing protocols, and ultrathin sections were incubated with anti-rCup a 3 rabbit polyclonal antibodies. RESULTS: Labeling of Cup a 3 was detected in mature and hydrated C. arizonica pollen grains. It was more intense in pollen from polluted air regions, and abundant gold particles were observed as they were released through the pollen grain walls. Furthermore, gold particles remained abundant in the pollen cytoplasm. The labeling was noticeably lower in pollen grains from unpolluted air regions. CONCLUSIONS: Cup a 3 is present in the cytoplasm and walls of cypress pollen grains during the air dispersion and hydration stages. The abundance of Cup a 3 in pollen grains under polluted air conditions indicates that these cypresses intensify their activity as a defense from environmental pollution, thus strengthening their allergenicity.  相似文献   
83.
Epitope mapping of outer surface protein C (OspC) by using sera from patients with neuroborreliosis led to the identification of one single major immunodominant epitope within the C-terminal 10 amino acid residues. Peptide binding studies and alanine replacement scanning of the C-terminal decapeptide, PVVAESPKKP, revealed a critical role for the PKKP sequence and its terminal carboxyl group for the binding of immunoglobulin M (IgM) antibodies from patients with Lyme borreliosis. Electron microscopy of antibody-labeled spirochetes indicated that the C-terminal region is exposed on the surface of the spirochete. Based on homology to proteins of known function, this region most probably adopts a polyproline II-like helix, which is found in surface-exposed structures involved in protein-protein interactions. This structural motif is highly conserved in Borrelia species causing Lyme borreliosis and subjected to purifying selection. We suggest that the abundance of the C-terminal region of OspC on the surface of B. burgdorferi allows a multimeric high-avidity interaction between the spirochete and surface Igs on B cells. The resulting cross-linking of surface Igs on B cells may induce a T-cell-independent B-cell activation without IgM-to-IgG switching, thus explaining the lack of IgG antibodies to OspC in neuroborreliosis.  相似文献   
84.
Lymphocyte Stimulation   总被引:1,自引:0,他引:1  
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85.
Within the GEN-COVID Multicenter Study, biospecimens from more than 1000 SARS-CoV-2 positive individuals have thus far been collected in the GEN-COVID Biobank (GCB). Sample types include whole blood, plasma, serum, leukocytes, and DNA. The GCB links samples to detailed clinical data available in the GEN-COVID Patient Registry (GCPR). It includes hospitalized patients (74.25%), broken down into intubated, treated by CPAP-biPAP, treated with O2 supplementation, and without respiratory support (9.5%, 18.4%, 31.55% and 14.8, respectively); and non-hospitalized subjects (25.75%), either pauci- or asymptomatic. More than 150 clinical patient-level data fields have been collected and binarized for further statistics according to the organs/systems primarily affected by COVID-19: heart, liver, pancreas, kidney, chemosensors, innate or adaptive immunity, and clotting system. Hierarchical clustering analysis identified five main clinical categories: (1) severe multisystemic failure with either thromboembolic or pancreatic variant; (2) cytokine storm type, either severe with liver involvement or moderate; (3) moderate heart type, either with or without liver damage; (4) moderate multisystemic involvement, either with or without liver damage; (5) mild, either with or without hyposmia. GCB and GCPR are further linked to the GCGDR, which includes data from whole-exome sequencing and high-density SNP genotyping. The data are available for sharing through the Network for Italian Genomes, found within the COVID-19 dedicated section. The study objective is to systematize this comprehensive data collection and begin identifying multi-organ involvement in COVID-19, defining genetic parameters for infection susceptibility within the population, and mapping genetically COVID-19 severity and clinical complexity among patients.Subject terms: Genetics research, Viral infection  相似文献   
86.
During the last few years, studies have revealed that the need for psychosocial support and concrete social services are great in the early stages of the treatment of rheumatic diseases. The ability to keep a job, to do household chores, to participate in leisure activities and to maintain social relations is clearly impaired. Anxiety and depression are not unusual and often associated with weak support from relatives, loneliness and disturbed family relations. Nevertheless, the patients report resilience and determination to cope with the impacts of illness. Crisis intervention, vocational guidance and counselling about problems concerning the disease should be available and offered to the patients. As the patients seem to be unaccustomed to talking about their psychosocial problems, an empathetic and information-seeking attitude on the part of the health care staff is essential.  相似文献   
87.
It is not evident how the small effects of the flankers of the Ebbinghaus figure on peak grip aperture (PGA) should be interpreted. One interpretation is that the flankers influence the estimated size, which in turn influences the grasp. If this interpretation is correct, then only the size-dependent aspects of the grasping movement should depend on the spatial positions of the flankers. An alternative interpretation is that the effect on grip aperture is caused by a change in judgement of the required precision, in which case various aspects of the grasping movement could be influenced by the size and position of the flankers. We presented subjects with a display consisting of a central disk surrounded by four large or small flankers. The array of circular flankers could be rotated by 45°. There were two tasks: to reproduce the perceived size of the central disk, and to grasp the central disk. As in other studies, the reproduced size and the PGA were both influenced by the size of the flankers. The effect on reproduced size settings was independent of the flankers spatial position. Nevertheless, the flankers position did influence the final grip aperture and the grip orientation at PGA and at movement offset. Because the flankers changed more than only the PGA, we conclude that the effect of the flankers on prehension cannot only be because of misjudgement of the size of the central disk.  相似文献   
88.
A 52-year-old man presented with heart failure of 1 month duration. He had undergone aortic valve and root replacement 30 months before admission. A continuous murmur was heard in the second intercostal space at the parasternal border. Aortography showed a pseudoaneurysm surrounding the aorta, whereas color Doppler study revealed flow from the central aorta to the pseudoaneurysm and flow from the pseudoaneurysm to the pulmonary artery trunk through a fistulous communication between them. Thus, fistulous communication with pulmonary artery causing heart failure is a complication of pseudoaneurysm after aortic and root replacement, which can be diagnosed clinically and echocardiographically.  相似文献   
89.
Epstein-Barr virus (EBV) DNA load values were measured in samples of whole blood (n = 60) and plasma (n = 59) by TaqMan PCR and in samples of peripheral blood lymphocytes (PBLs) (n = 60) by competitive PCR (cPCR). The samples were obtained from 44 transplant recipients. The whole-blood and PBL loads correlated highly (r(2) > 0.900), whereas the plasma and PBL loads correlated poorly (r(2) = 0.512). Testing of whole blood by TaqMan PCR is an acceptable alternative to testing of PBLs by cPCR for quantifying EBV DNA load.  相似文献   
90.
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