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1.
The opening of a communication channel between brain and computer [brain-computer interface (BCI)] is possible by using changes in electroencephalogram (EEG) power spectra related to the imagination of movements. In this paper, we present results obtained by recording EEG during an upper limb motor imagery task in a total of 18 subjects by using low-resolution surface Laplacian, different linear and quadratic classifiers, as well as a variable number of scalp electrodes, from 2 to 26. The results (variable correct classification rate of mental imagery between 75% and 95%) suggest that it is possible to recognize quite reliably ongoing mental movement imagery for BCI applications.  相似文献   
2.
The authors report the experience of 47 patients submitted to surgery for hepatic hydatidosis. Results from different therapeutic procedures are then compared. Finally, possible biliary complications of the hepatic echinococcosis and their surgical treatment are discussed.  相似文献   
3.
Outer Membrane Vesicles (OMV) constitute a promising platform for the development of efficient vaccines. OMV can be decorated with heterologous antigens (proteins or polysaccharides), becoming attractive novel carriers for the development of multicomponent vaccines. Chemical conjugation represents a tool for linking antigens, also from phylogenetically distant pathogens, to OMV. Here we develop two simple and widely applicable conjugation chemistries targeting proteins or lipopolysaccharides on the surface of Generalized Modules for Membrane Antigens (GMMA), OMV spontaneously released from Gram-negative bacteria mutated to increase vesicle yield and reduce potential reactogenicity. A Design of Experiment approach was used to identify optimal conditions for GMMA activation before conjugation, resulting in consistent processes and ensuring conjugation efficiency. Conjugates produced by both chemistries induced strong humoral response against the heterologous antigen and GMMA. Additionally, the use of the two orthogonal chemistries allowed to control the linkage of two different antigens on the same GMMA particle. This work supports the further advancement of this novel platform with great potential for the design of effective vaccines.  相似文献   
4.
A case of juvenile polyposis associated with hereditary spherocytosis is presented. All the anomalies associated with juvenile polyposis coli reported in the literature are reviewed. The clinical consequences of such a report are discussed along with the different forms of therapy for treating juvenile polyposis coli. To our knowledge, this is the first report in the literature of juvenile polyposis associated with hereditary spherocytosis.  相似文献   
5.
IVS10nt546 (IVS10nt-11g-->a) is the most common molecular defect of the phenylalanine hydroxylase gene causing phenylketonuria in Mediterranean populations. Previous studies have proposed various and alternative hypotheses concerning the geographical origin and pattern of diffusion of this mutation in this area. In this study, this issue was re-examined on a large sample (149) of "Mediterranean" IVS10nt546 mutant alleles analysed with multiallelic intragenic polymorphisms. The analysis of intragenic microsatellite (STR) and minisatellite (VNTR) polymorphisms shows allelic heterogeneity of the IVS10nt546 mutation. Eight STR and three VNTR alleles were found in association with the splicing defect. Of the ten detected STR-VNTR combinations ("minihaplotypes"), we identified a predominant allelic association (VNTR7-STR252) embedded in a RFLP-haplotype 6 background, which seems to correspond to the ancestral gene originating in the Turkey-Israel area. Analysis of both absolute and relative gene frequencies of the STR252-IVS10nt546-VNTR7 minihaplotypes, shows statistically significant (P < 0.02) variations and may suggest gene flow from Turkey and/or Israel to Italy and Spain. The associated migratory events need not be unique in time (and people) but seem to suggest they may be traced back to the expansion of the Neolithic culture and people, thus allowing dating of the origin of this mutation to at least 5000-10000 years ago. Alternative hypotheses are discussed to explain, in light of the available historical and pre-historical evidence, the pattern of diffusion of the IVS10nt546 mutation in the Mediterranean basin.  相似文献   
6.
Recent successful applications of NMR spectroscopy and imaging in food science prompted the authors to use these new techniques for the analysis of espresso coffee. The target of this work was to identify an experimental procedure to obtain maximum information from high‐resolution 1H spectra. Only the espresso coffee was considered as the true food, since it includes all aromatic substances responsible for the coffee aroma and taste. A big effort was made in order to select an easy, quick and non‐degrading procedure to analyse the espresso cup content, preventing artificial or natural degradation effects with a particular care in the measurement of labile and volatile components. The procedure was tested on two arabica and one robusta samples; each sample was prepared with three roasting degrees to follow the chemical changes due to the roasting process. Moreover, one water extract was prepared also from ground green coffees. As a comparison, each coffee extract was prepared both with a standard ‘espresso coffee machine’ and with a ‘mocha’ as used in the domestic setting. Significant differences among the three samples were observed. Moreover, for all samples, as a function of the roasting degree, a clear trend in the chemical composition was observed. © 1999 Society of Chemical Industry  相似文献   
7.
Infertility is assumed to arise exclusively from male- and female-dependent pathological factors. However, recent studies have indicated that reproductive failure may also result from the reproductive incompatibility of the partners. Selection against such incompatibilities likely occurs via female-derived reproductive secretions, including follicular fluid (FF), that mediate gamete-level mate choice towards the sperm of specific males. To facilitate potential development of diagnostic tests for human reproductive incompatibility, we examined whether sperm physiological response to female serum indicate male–female compatibility in the presence of FF. We performed a full-factorial experiment, in which the sperm of 10 males were treated with the FF and serum of 6 healthy females. We found that sperm motility and viability in both biofluids were highly similar and that in 70% of the males, sperm serum treatment predicted male–female compatibility. We also identified male human leucocyte antigen (HLA) alleles and female (FF and serum) anti-HLA antibodies and tested whether the number of allele–antibody matches predict sperm physiological response to female fluids. However, no association was found between measured sperm traits and the number of allele–antibody matches. Overall, the present results may open novel possibilities for the future development of reproductive incompatibility tests and may pave the way towards more accurate infertility diagnostics and treatments.  相似文献   
8.
We consider two approaches to the stable marriage problem: proposal algorithms and describing the stable matching polytope using linear inequalities. We illuminate the relationship between the two approaches. Beginning with a set of linear inequalities that describe the stable matching polytope, we describe a process of refining the set of linear inequalities by eliminating redundant constraints and pruning the preference lists to eliminate unattainable assignments. We show that it is trivial to use the pruned preference lists to find the firm-optimal and worker-optimal stable matchings. We then describe a new procedure that combines a proposal algorithm and our refining process to find a stable matching that does not favor one group over the other. Finally, we apply our refining process to problems in which couples submit preferences over pairs of positions.  相似文献   
9.
Sodium phenylbutyrate (NaPB) is used in urea cycle disorders. We screened 6 neuroblastoma cell lines for in vitro potency of NaPB as an antiproliferative agent, evaluated multiple dosing schedules, and assessed its activity in combination with clinically active agents for neuroblastoma. We determined that NaPB achieves a 30-80% growth inhibition at 5 mM. Repeated dosing and prolonged drug exposure enhanced the cytotoxic effect. NaPB had additive cytotoxic effects when administered with vincristine; however, NaPB did not affect the activity of etoposide, adriamycin, 4-hydroxycyclophosphamide or cisplatinum. These results suggest that NaPB is an active agent against neuroblastoma and could be combined with vincristine in novel chemotherapy regimens.  相似文献   
10.
Visceral larva migrans (VLM) is a clinical syndrome caused by infection of man by Toxocara spp, the common roundworm of dogs and cats. Tissue migration of larval stages causes illness specially in children. Because larvae are difficult to detect in tissues, diagnosis is mostly based on serology. After the introduction of the enzyme-linked immunosorbent assay (ELISA) using the larval excretory-secretory antigen of T. canis (TES), the diagnosis specificity was greatly improved although cross-reactivity with other helminths are still being reported. In Brazil, diagnosis is routinely made after absorption of serum samples with Ascaris suum antigens, a nematode antigenically related with Ascaris lumbricoides which is a common intestinal nematode of children. In order to identify T. canis antigens that cross react to A. suum antigens we analyzed TES antigen by SDS-PAGE and Western blotting techniques. When we used serum samples from patients suspected of VLM and positive result by ELISA as well as a reference serum sample numerous bands were seen (molecular weight of 210-200 kDa, 116-97 kDa, 55-50 kDa and 35-29 kDa). Among these there is at least one band with molecular weight around 55-66 kDa that seem to be responsible for the cross-reactivity between T. canis and A. suum once it disappears when previous absorption of serum samples with A. suum antigens is performed.  相似文献   
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