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1.
OBJECTIVE: This study aimed to describe the use of the P300 event-related potential as a control signal in a brain computer interface (BCI) for healthy and paralysed participants. METHODS: The experimental device used the P300 wave to control the movement of an object on a graphical interface. Visual stimuli, consisting of four arrows (up, right, down, left) were randomly presented in peripheral positions on the screen. Participants were instructed to recognize only the arrow indicating a specific direction for an object to move. P300 epochs, synchronized with the stimulus, were analyzed on-line via Independent Component Analysis (ICA) with subsequent feature extraction and classification by using a neural network. RESULTS: We tested the reliability and the performance of the system in real-time. The system needed a short training period to allow task completion and reached good performance. Nonetheless, severely impaired patients had lower performance than healthy participants. CONCLUSIONS: The proposed system is effective for use with healthy participants, whereas further research is needed before it can be used with locked-in syndrome patients. SIGNIFICANCE: The P300-based BCI described can reliably control, in 'real time', the motion of a cursor on a graphical interface, and no time-consuming training is needed in order to test possible applications for motor-impaired patients.  相似文献   
2.
Simple numerical chromosome aberrations have been observed in tumorigenesis and may point to indicative initiating or early events in tumorigenesis. We have identified two cases of ovarian carcinomas with trisomy of chromosome 10 using conventional GTG-banding and fluorescence in situ hybridization. This is, to our knowledge, the first report of trisomy 10 as a simple karyotypic abnormality observed in ovarian carcinoma. These results suggest that further studies investigating whether chromosome 10 genes are associated with the pathogenesis of some ovarian tumors are warranted.  相似文献   
3.
Multidrug-resistant isolates of a clonal lineage of Pseudomonas aeruginosa producing the VIM-2 metallo-beta-lactamase (MBL), involved in a large outbreak in an Italian hospital, were compared with MBL-negative strains that had caused outbreaks in two French hospitals. Although the isolates had different carbapenem MICs, the VIM-2-producing isolates from Italy carried identical, or very similar, allelic forms of the oprD gene, harboured a common class 1 integron, belonged to the same multilocus sequence type (ST111), and showed macrorestriction profiles that were related to those of the MBL-negative French strains. These results support the concept of independent acquisition of resistance determinants by members of a widespread clonal lineage of P. aeruginosa.  相似文献   
4.
CD16 surface antigens represent activatory molecules in CD3-16+ NK cells. In order to target NK cells against relatively NK-resistant ovarian carcinomas, we used an anti-CD16 monoclonal antibody (MAb) (VD4), together with an anti-ovarian carcinoma-associated antigen (MOV19), to construct biMAbs. To this end, hybrid hybridomas were generated by fusing a TK-deficient VD4 hybridoma mutant with a HGPRT-deficient MOV19 hybrid. Supernatants from hybrid hybridomas that had been selected in HAT medium were screened for their ability to induce a CD3-16+ NK clone to lyse an MOV19+ ovarian carcinoma cell line in a 4-hr 51Cr-release assay. The NMB.45 hybrid hybridoma secreted a biMAb which triggered lysis of MOV19+ but not of MOV19- target cells. Some degree of target cell lysis was also observed with MOV19 MAb (due to ADCC mechanisms), while the VD4 MAb was ineffective. HPLC fractionation of MAbs secreted by the hybrid hybridoma made it possible to identify 4 different peaks, one of which appeared to contain functional biMAb molecules. HPLC-purified biMAb (100 ng/ml) induced resting PBL to lyse the "NK-resistant" IGROVI ovarian carcinoma cell line. Fresh MOV19+ tumor cells were also lysed, although with lower efficiency. When IL-2-activated lymphocytes were used as a source of effectors, biMAb caused only minor increases in the IL-2-induced cytolytic activity. Further analyses of the effect of biMAb were performed at the clonal level. Among CD3-16+ NK cell clones, a clear enhancing effect could be observed only in GL183+ but not in GL183- clones. In CD3+ cytotoxic clones a triggering effect could be detected in one out of 4 TCR gamma/delta+ clones but not in TCR alpha/beta+ clones.  相似文献   
5.
A prospective study of surgical infections in our Department of Surgery in the years 1986-1989 is reported. 2719 patients entered the study: they represent the total number of patients operated in the above said period (628 urgent and 2091 elective operations). As suggested in 1964 by Altmeier, surgical procedures were classified in four groups according to the potential risk of intraoperative contamination. For every septic complication observed pertinent cultures were performed and responsible pathogens identified. We present our protocol of antibacterial prophylaxis which distinguishes antibiotics given as "ultra short term", "short term", "antibiotic prophylaxis". The results obtained and particularly the total number of infections (3.9%), and the percentage of infections in group 3 (4.6%) and in group 4 (23.1%) procedures validate the usefulness of antibiotic prophylaxis in these patients. In group 1 and group 2 patients the usefulness of antibiotic prophylaxis seems very doubtful.  相似文献   
6.
7.
Parasitic diseases affecting goats are able to cause major economic losses, standing out, among them, the lice infestation. According to the literature, lice can act as vectors of other diseases, including the ones caused by blood protozoan. In this sense, this survey study aimed to assess the ectoparasites of goats in the west region of Santa Catarina (SC). Two hundred seventeen goats from 24 different rural properties located in 17 towns in SC were examined. From them, ectoparasites were collected and evaluated in laboratory, where the parasitological classification was performed. In 13 properties, it was possible to identify ectoparasites. Damalinia caprae lice were observed in 126 animals (58 %), while Linognathus stenopsis were found in 10 animals (4.6 %). It is noteworthy that, in these properties, all the animals were under lice parasitism, independent of sex or age. The goats had peeling skin, particularly in the back region (lumbar). All of the 24 properties evaluated were reported having problems with lice in different seasons of the year, even under regular treatment with cypermethrin (spraying). Based on our findings, it was possible to conclude that D. caprae is the major ectoparasite of goats in the investigated area.  相似文献   
8.
9.
BACKGROUND: The optimal virologic and immunologic stage at which to initiate antiretroviral therapy in individuals infected with human immunodeficiency virus type 1 (HIV-1) is undefined. METHODS: Among 1054 HIV-1-infected women in a prospective cohort study, we determined the time from initiation of highly active antiretroviral treatment (HAART) to acquired immunodeficiency syndrome (AIDS) and death. RESULTS: Median follow-up was 3.4 years. Of 553 women without AIDS at HAART initiation, 62 (11%) developed AIDS. Compared with women with CD4(+) cell counts greater than 350/microL at HAART initiation, women with cell counts of 200 to 350/microL and less than 200/microL had relative hazards (RHs) for progression to AIDS of 0.93 (95% confidence interval [CI], 0.46-1.86) and 2.48 (95% CI, 1.39-4.42), respectively. Compared with those with HIV-1 RNA values less than 5000 copies/mL, women with 5000 to 50,000 copies/mL and greater than 50,000 copies/mL had RHs of 1.39 (95% CI, 0.74-2.64) and 2.09 (95% CI, 1.09-3.99), respectively. Among women with AIDS at HAART initiation (n = 501), RHs of death were 1.97 (95% CI, 0.84-4.66) and 3.35 (95% CI, 1.59-7.08) with CD4(+) cell counts of 200 to 350/microL and less than 200/microL, respectively, relative to those with greater than 350/microL, and 1.90 (95% CI, 0.84-4.30) and 3.70 (95% CI, 1.81-7.54) for those with HIV-1 RNA values of 5000 to 50,000 and greater than 50,000 copies/mL, respectively, relative to those with less than 5000 copies/mL. CONCLUSIONS: Progression to AIDS and death was predicted by pre-HAART values of less than 200/microL for CD4(+) cells and greater than 50,000 HIV-1 RNA copies/mL, indicating that deferral of HAART until the CD4(+) cell count is between 350 and 200/microL is a valid strategy in the clinical management of HIV-1 infection.  相似文献   
10.
The relationships among hemoglobin, ferritin, and transferrin receptor levels and 2 markers of human immunodeficiency virus (HIV) disease severity--HIV load and CD4(+) lymphocyte count--were characterized among 483 pregnant women in Malawi, Africa. The only significant correlation was an inverse correlation between hemoglobin level and plasma HIV load (r=-.104; P<.03). The prevalence of iron deficiency anemia was not significantly different across quartiles of HIV load or CD4(+) lymphocyte count. In contrast to previous studies, these data suggest that iron status is not related to markers of HIV disease severity in pregnant women in Africa.  相似文献   
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