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991.
992.
Few studies have examined the impact of repetitive transcranial magnetic stimulation (rTMS) on the cortical excitability of nonmotor cortices; current treatments often target the temporal or prefrontal cortex. We used auditory evoked potentials recorded in 24 healthy subjects to evaluate the neuromodulatory effects of low‐ and high‐frequency rTMS in the temporal lobe. Both auditory evoked potential P50 amplitude, a marker of cortical excitability, and P50 ratio, a marker of sensory gating known to be impaired in patients with auditory verbal hallucinations, were compared before and after rTMS. We observed a similar effect after both stimulation frequencies, with a decrease in P50 amplitude and no significant effect on P50 ratio. Low‐ and high‐frequency rTMS applied to the temporal lobe seemed to exert the same cortical neuromodulation effect, while auditory sensory gating may not be modulated by temporal rTMS.  相似文献   
993.
Host-adapted Gram-negative bacterial pathogens from the Pasteurellaceae, Neisseriaceae, and Moraxellaceae families normally reside in the upper respiratory or genitourinary tracts of their hosts and rely on utilizing iron from host transferrin (Tf) for growth and survival. The surface receptor proteins that mediate this critical iron acquisition pathway have been proposed as ideal vaccine targets due to the critical role that they play in survival and disease pathogenesis in vivo. In particular, the surface lipoprotein component of the receptor, Tf binding protein B (TbpB), had received considerable attention as a potential antigen for vaccines in humans and food production animals but this has not translated into the series of successful vaccine products originally envisioned. Preliminary immunization experiments suggesting that host Tf could interfere with development of the immune response prompted us to directly address this question with site-directed mutant proteins defective in binding Tf. Site-directed mutants with dramatically reduced binding of porcine transferrin and nearly identical structure to the native proteins were prepared. A mutant Haemophilus parasuis TbpB was shown to induce an enhanced B-cell and T-cell response in pigs relative to native TbpB and provide superior protection from infection than the native TbpB or a commercial vaccine product. The results indicate that binding of host transferrin modulates the development of the immune response against TbpBs and that strategies designed to reduce or eliminate binding can be used to generate superior antigens for vaccines.  相似文献   
994.
The article analyzes access to various information and communication technologies (ICTs; mobile phone, computer, Internet, e‐mail, and social network sites) among a representative sample of homeless people in Madrid. The information was collected using a structured interview. The results show that new ICTs are used to some extent among homeless people in Madrid, although at much lower percentages than the general population in Spain. We observed a relatively widespread use of mobile phones, a medium‐low level use of the Internet, computer, and e‐mail, and hardly any use of social networks, with significant differences according to the interviewees' age, level of education, and Spanish or foreign nationality. The digital divide has an especially negative effect on elderly homeless people, those with lower levels of education, and those of Spanish origin.  相似文献   
995.
996.
Cytogenetic abnormalities, evaluated either by karyotype or by fluorescence in situ hybridization (FISH), are considered the most important prognostic factor in multiple myeloma (MM). However, there is no information about the prognostic impact of genomic changes detected by comparative genomic hybridization (CGH). We have analyzed the frequency and prognostic impact of genetic changes as detected by CGH and evaluated the relationship between these chromosomal imbalances and IGH translocation, analyzed by FISH, in 74 patients with newly diagnosed MM. Genomic changes were identified in 51 (69%) of the 74 MM patients. The most recurrent abnormalities among the cases with genomic changes were gains on chromosome regions 1q (45%), 5q (24%), 9q (24%), 11q (22%), 15q (22%), 3q (16%), and 7q (14%), while losses mainly involved chromosomes 13 (39%), 16q (18%), 6q (10%), and 8p (10%). Remarkably, the 6 patients with gains on 11q had IGH translocations. Multivariate analysis selected chromosomal losses, 11q gains, age, and type of treatment (conventional chemotherapy vs autologous transplantation) as independent parameters for predicting survival. Genomic losses retained the prognostic value irrespective of treatment approach. According to these results, losses of chromosomal material evaluated by CGH represent a powerful prognostic factor in MM patients.  相似文献   
997.
Runs of homozygosity (ROHs) are extended genomic regions of homozygous genotypes that record populations’ mating patterns in the past. We performed microarray genotyping on 15 individuals from a small isolated Tunisian community. We estimated the individual and population genome‐wide level of homozygosity from data on ROH above 0.5 Mb in length. We found a high average number of ROH per individual (48.2). The smallest ROH category (0.5–1.49 Mb) represents 0.93% of the whole genome, while medium‐size (1.5‐4.99 Mb) and long‐size ROH (≥5 Mb) cover 1.18% and 0.95%, respectively. We found that genealogical individual inbreeding coefficients (Fped) based on three‐ to four‐generation pedigrees are not reliable indicators of the current proportion of genome‐wide homozygosity inferred from ROH (FROH) either for 0.5 or 1.5 Mb ROH length thresholds, while identity‐by‐descent sharing is a function of shared coancestry. This study emphasizes the effect of reproductive isolation and a prolonged practice of consanguinity that limits the genetic heterogeneity. It also provides evidence of both recent and ancient parental relatedness contribution to the current level of genome‐wide homozygosity in the studied population. These findings may be useful for evaluation of long‐term effects of inbreeding on human health and for future applications of ROHs in identifying recessive susceptibility genes.  相似文献   
998.
OBJECTIVE: To assess the accuracy of the determination of Helicobacter pylori infection by a stool immunoassay in patients with upper-gastrointestinal bleeding (UGB) of peptic origin, in comparison with the routine histological study, serology, rapid urease and 13C-breath tests. METHODS: Sixty-eight patients with endoscopically proven UGB of peptic origin were included. The presence of H. pylori was considered when observed on histology or, if negative, by the positive indications of two of the remaining tests (serology, rapid urease,13C-breath test). The accuracy of stool immunoassay was estimated according to results obtained with other diagnostic methods. RESULTS: Lesions causing gastrointestinal bleeding were 49 duodenal ulcers, 11 gastric ulcers, six pyloric channel ulcers, 13 acute lesions of the gastric mucosa, and 16 erosive duodenitis. H. pylori infection was present in 59 (86.76%) patients. Forty-one patients had received nonsteroidal anti-inflammatory drugs. The sensitivity and specificity of the diagnostic methods were 47.5% and 100% for the rapid urease test, 93% and 87.5% for the breath test, 86.4% and 77.7% for serology, 89.4% and 100% for histology, and 96.6% and 33.3% for the stool test. CONCLUSIONS: The detection of H. pylori antigen in stools in patients with UGB of peptic origin has a good sensitivity (96.6%) but a low specificity (33.3%) for the diagnosis of H. pylori infection, which probably makes this test an inadequate tool in this setting if utilized alone.  相似文献   
999.
The aim of the study was to explore the experiences of night nurses. An interpretative phenomenological study was undertaken, and 35 nurses working in Italian medical, surgical and intensive care units were purposely recruited. Data were gathered in 2010 by semi‐structured interviews, collecting nurses' narratives, memorable cases and metaphors, aimed at summarising the essence of work as a nurse during the night. The experience of night nursing is based on four interconnected themes: (i) working in a state of alert, (ii) growing by expanding autonomy and responsibility, (iii) assuring sensitive surveillance and (iv) experiencing deep intimacy. Memorable episodes were polarised along (i) expected/unexpected events; (ii) positive/negative epilogues; and (iii) life/death issues. Many of the emergent metaphors described working during the night as being in the middle of a space where an apparent calm scene takes place, but unpredictable factors may suddenly change the order of events and the outcomes, creating chaos. Working during the night alerts nurses, who increase autonomy, expanding their role and assuming more responsibility with respect to that assumed during daily shifts. The nurses' clinical reasoning is based on data they carefully listen to, and on the meaning that nurses give time by time to different noises and silence. While in the past a sense of companionships was reported, a loneliness or a ‘neutral’ experience concerning the relationships with colleagues seems to prevail during night nursing. Working night shifts is a complex task, and specific training must be assured to students/novices.  相似文献   
1000.
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