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91.
92.
Facial expression recognition by people with mobius syndrome   总被引:1,自引:0,他引:1  
We present an investigation of facial expression recognition by three people (BC, LP, and NC) with Mobius syndrome, a congenital disorder producing facial paralysis. The participants were asked to identify the emotion displayed in 10 examples of facial expressions associated with each of 6 basic emotions from the Ekman and Friesen (1976) series. None of the three people with Mobius syndrome was significantly impaired on this task. On a second test of facial expression recognition using computer-morphed facial expressions, NC showed a statistically significant impairment, BC a borderline deficit, and LP was unimpaired. However, even when impairments were found, people with Mobius syndrome still recognised many of the facial expressions shown to them. The recognition of facial expressions by people who have never been able to produce such signals on their own faces demonstrates that the ability to produce facial expressions is not a necessary prerequisite of their recognition.  相似文献   
93.
94.
AIM: To examine strains of Pseudomonas aeruginosa for specific antifungal factors. METHODS: Two clinical strains of P aeruginosa with strong in vitro inhibition (by cross streak assay) of Candida albicans and Aspergillus fumigatus were examined. Both strains were isolated from sputum--one from a patient with cystic fibrosis and one from a patient with bronchiectasis. Bacterial extracts were fractionated by high performance liquid chromatography and examined by ultraviolet absorbance and mass spectroscopy. Antifungal activity against C albicans and A fumigatus was determined in a well plate assay. RESULTS: Pyocyanin was the major antifungal agent of P aeruginosa; 1-hydroxy-phenazine also possessed activity. Pyocyanin MICs for C albicans and A fumigatus were > 64 micrograms/ml. These phenazines were active against nine other yeast species pathogenic for man. Preliminary experiments also suggested possible inhibition of yeast mycelial transformation in C albicans by pyocyanin. CONCLUSIONS: There may be a role for pyocyanin and 1-hydroxyphenazine in the prevention of pulmonary candidiasis in patients colonised by P aeruginosa.  相似文献   
95.
Diagnosis of coccidioidomycosis largely depends on serologic tests. In this investigation, the enzyme-linked immunosorbent assay (ELISA) was used to detect patient immunoglobulin M (IgM) precipitin antibody binding to a 120-kilodalton (kDa) fraction previously isolated from an alkali-soluble, water-soluble extract of the arthroconidial wall and mycelial culture filtrate plus toluene lysate of Coccidioides immitis. Results of the serologic response to this tube precipitin antigen (TP-Ag) in the ELISA correlated well with results of immunodiffusion assays of 30 serum samples from patients. Immunoelectron microscopic examinations of arthroconidia and spherules were performed with patient IgM precipitin antibodies isolated from sera eluted over a solid-phase immunosorbent column containing the purified 120-kDa TP-Ag. The antibody probe located the 120-kDa TP-Ag on the walls of in vitro-grown arthroconidia and spherules. Pronase digestion and heating (100 degrees C, 5 min) had no apparent effect on the activity of the 120-kDa TP-Ag, while periodate oxidation resulted in total loss of its immunodiffusion-TP activity. Analysis of the carbohydrate composition of the TP-Ag revealed xylose, 3-O-methylmannose (3-O-MM), mannose, galactose, and glucose. Competitive inhibition ELISAs were used to demonstrate that 3-O-MM is largely responsible for the reactivity of IgM precipitin antibodies with the 120-kDa TP-Ag. Synthetic 3-O-MM may be a useful probe for detection of anti-Coccidioides precipitin antibodies in the ELISA.  相似文献   
96.
Streptococcus pneumoniae culture filtrates and pneumolysin both slow human ciliary beating and damage respiratory epithelium in vitro. A polyclonal pneumolysin antibody bound to sepharose beads removed pneumolysin from culture filtrates and showed that pneumolysin alone was responsible for the effects on epithelium. In a 48-h organ culture pneumolysin caused ciliary slowing and epithelial disruption in a dose-dependent manner down to 5 ng/ml. Comparison of the ciliary slowing activity and pneumolysin concentration in filtrates in a continuous broth culture showed a maximal effect at 16 h (pneumolysin 7.5 micrograms/ml). Later the activity decreased while the pneumolysin concentration increased (8.8 micrograms/ml). This loss of activity was prevented by neutralisation of the acid pH of the culture medium. Eight different culture filtrates produced significant (P less than 0.05) ciliary slowing which correlated (r = 0.95) with simultaneously measured haemolytic (pneumolysin) activity. Substitution of tryptophan (position 433) by phenylalanine reduced the haemolytic and ciliary slowing activity of pneumolysin, but did not affect its ability to activate complement. There was no correlation between the ciliary slowing produced by the culture filtrate and that produced by the autolysate of a particular strain, nor between ciliary slowing and the extent of autolysis or the serotype of the strain.  相似文献   
97.
Coccidioides is a fungal pathogen of humans which can cause a life-threatening respiratory disease in immunocompetent individuals. Recurrent epidemics of coccidioidal infections in Southwestern United States has raised the specter of awareness of this soil-borne microbe, particularly among residents of Arizona and Southern California, and has galvanized research efforts to develop a human vaccine against coccidioidomycosis. In this review, we discuss the rationale for such a vaccine, examine the features of host innate and acquired immune response to Coccidioides infection, describe strategies used to identify and evaluate vaccine candidates, and provide an update on progress toward development of a vaccine against this endemic pathogen.  相似文献   
98.
EXT1 and EXT2 are genes that have been shown to cause hereditary multiple exostosis (HME), a syndrome marked by the formation of bony growths juxtaposed to the growth plate. These genes are members of a growing family of proteins with glycosyltransferase activity required for the synthesis of heparan sulfate chains. This protein activity is predicted to play a role in the expression of proteoglycans on the cell surface and in the extracellular matrix. We and others have previously suggested that a two-hit mutational model applies to the development of an exostosis where a germline mutation coupled with a somatic mutation results in the loss of EXT1 or EXT2 function and subsequent tumor formation. We report the direct sequencing and loss of heterozygosity (LOH) analysis of 12 exostoses from 10 HME families, 4 solitary exostoses, and their corresponding constitutional DNA. Of the 16 exostoses screened, we find only one solitary case in which two somatic mutations, a deletion and an LOH, are present. This provides limited support for the two-hit hypothesis involving the EXT1 and EXT2 genes for the development of an exostosis. Alternative models are developed based on the functional significance of EXT proteins in heparan sulfate biosynthesis.  相似文献   
99.
The prophylactic and therapeutic effects of gold sodium thiomalate, cyclosporin A, cyclophosphamide, and placebo on collagen-induced arthritis (CIA) were evaluated in DA rats. Prophylactic treatment with cyclosporin A and cyclophosphamide suppressed the arthritis incidence, clinical inflammation, destructive bone changes, and development of anti-collagen antibody in DA rats subsequently injected with porcine type-II collagen. Therapeutic treatment with cyclosporin A and cyclophosphamide had a definite suppression on established CIA when started 21 days after the initial collagen injection, but the suppression was less marked than that of prophylactic treatment. Gold had no impact on CIA in DA rats when administered either prophylactically or therapeutically.  相似文献   
100.
Factor analyses to create the Multidimensional Pain Inventory (MPI) warrant further examination due to small sample size, the use of separate factor analyses for each MPI section, and lack of evidence for the replicability of the factor model. The present study randomly assigned 972 respondents to one of three samples. Study 1 used data from Sample 1 (n = 452) to examine the replicability of the MPI factor structure reported by Kerns, Turk, and Rudy (1985), and to measure the internal consistencies of MPI scales. In Study 2, confirmatory factor analyses using Sample 2 data (n = 267) verified a revised MPI factor structure that was generated in Study 1; cross-validation was achieved using data from Sample 3 (n = 253). The revised MPI model differed from the original model in its number of scales and pattern of scale loadings. Recommendations for the refinement of the MPI are proposed.  相似文献   
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