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991.
Pattern evoked responses were recorded in 46 patients of tuberculosis on ethambutol and 16 healthy subjects. Deterioration in visual acuity was documented in two patients (4.3%). P100 latency was delayed in 16 cases (34.8%), while in 12 patients (26.1%) both latency and amplitude were affected. A cut off latency value of > or = 140 ms was associated with ophthalmological findings. The incidence of subclinical toxicity as detected by visual evoked response (VER) was higher in older subjects, patients on higher doses of ethambutol (> or = 20 mg/kg/day) and longer duration of treatment. Of two cases with objective ocular signs, one who reported for follow up after two months had recovered completely after stopping ethambutol. Recording of VER is an extremely useful objective test for subclinical optic nerve damage.  相似文献   
992.
This study examined the effects on food choice of increasing the number of healthy items available (fruit) and decreasing the number of unhealthy items available (candy bars). A similar choice, involving nonfood items, was also examined. Two hundred eighty-nine men and women were randomly assigned to 1 of 4 experimental groups: (a) control group, (b) increased number of fruits, (c) decreased number of candy bars, and (d) combination. Between 30% and 40% of participants chose fruit regardless of the amount of fruit and candy presented: there was no effect of increasing fruit or decreasing candy bars. However, restrained participants and current dieters were more likely to choose fruit. In contrast, both stimulus control techniques were effective in increasing the percentage of participants choosing a nonfood item. These results suggest that stimulus control may not be sufficient to modify food choice: other powerful factors affect eating behavior, and these must be considered.  相似文献   
993.
We showed previously that HIV-1 Rev Response Element (RRE) contains a certain degree of structural variation, and in a set of limited samples, RRE from HIV-1 natural isolates were found to have functional variability. The significance of the RRE heterogeneity is addressed further by analyzing the functional variation of RREs in a longitudinal cohort. While the RRE activity at early time points was not a good predictor of disease outcome, the RRE activity at late time points was correlated with rates of CD4+ count decline. These data suggest that RRE heterogeneity may be important in viral pathogenesis and disease progression.  相似文献   
994.
Recent advances in automatic speech recognition and related technologies allow computers to carry on conversations by telephone. We developed an intelligent dialogue system that interacts with hypertensive patients to collect data about their health status. Patients thus avoid the inconvenience of traveling for frequent face to face visits to monitor the clinical variables they can easily measure at home; the physician is facilitated in acquiring patient information and cardiovascular risk, which is evaluated from the data according to noted guidelines. Controlled trials to assess the clinical efficacy are under way.  相似文献   
995.
Campylobacter jejuni-induced enteritis is the most common infection preceding Guillain-Barre syndrome (GBS), an immune-mediated polyradiculoneuritis. The acute autoimmune attack is thought to be based on C. jejuni antigens which may mimick antigens of the peripheral nervous system. Additional pathomechanisms, like disturbance of natural T cell immunoregulation by C. jejuni, have not been evaluated so far. In experimental autoimmune neuritis (EAN), a T lymphocyte-mediated animal model of human GBS, tolerance to myelin-derived autoantigens can be induced by oral feeding of the respective antigen. Here we investigated whether the lipooligosaccharide (LOS) fraction of C. jejuni may directly alter immunologic tolerance through gastrointestinal pathways. While EAN, actively induced by immunization with bovine peripheral nerve myelin could be ameliorated by precedent feeding of myelin, feeding of C. jejuni LOS along with the myelin antigen not only prevented the tolerizing effects of oral myelin but even accelerated the onset of overt EAN and augmented the myelin-specific B cell response. These findings provide evidence that LOS of C. jejuni, as produced in the gut during C. jejuni-induced enteritis, can disturb natural tolerance to definite proteins which may be or may mimic peripheral nerve antigens. In human patients this may be one of the potential mechanisms to explain why C. jejuni enteritis is a common trigger of GBS.  相似文献   
996.
This paper reports the results of a longitudinal study of malaria incidence (1998-2002) among the Pakaanóva (Wari') Indians, Brazilian southwest Amazon region, based on data routinely gathered by Brazilian National Health Foundation outposts network in conjunction with the Indian health service. Malaria is present yearlong in the Pakaanóva. Statistically significant differences between seasons or months were not noticed. A total of 1933 cases of malaria were diagnosed in the Pakaanóva during this period. The P. vivax / P. falciparum ratio was 3.4. P. vivax accounted for 76.5% of the cases. Infections with P. malariae were not recorded. Incidence rates did not differ by sex. Most malaria cases were reported in children < 10 years old (45%). About one fourth of all cases were diagnosed on women 10-40 years old. An entomological survey carried out at two Pakaanóva villages yielded a total of 3.232 specimens of anophelines. Anopheles darlingi predominated (94.4%). Most specimens were captured outdoors and peak activity hours were noted at early evening and just before sunrise. It was observed that Pakaanóva cultural practices may facilitate outdoor exposure of individuals of both sexes and all age groups during peak hours of mosquito activities (e.g., coming to the river early in the morning for bathing or to draw water, fishing, engaging in hunting camps, etc). In a context in which anophelines are ubiquitous and predominantly exophilic, and humans of both sexes and all ages are prone to outdoor activities during peak mosquito activity hours, malaria is likely to remain endemic in the Pakaanóva, thus requiring the development of alternative control strategies that are culturally and ecologically sensitive.  相似文献   
997.
The electrostatic spray deposition (ESD) technique offers the possibility of depositing calcium phosphate (CaP) coatings onto various substrate materials with defined chemical and morphological properties. The relationship between physical, apparatus-related deposition parameters, and the chemical characteristics of ESD coatings was investigated by means of X-ray diffraction, Fourier transform infrared spectroscopy, and energy dispersive spectroscopy to be able to deposit CaP coatings with tailored chemical properties. The results showed that the chemical characteristics of CaP coatings, deposited with use of the ESD technique, were strongly dependent on the deposition temperature, the nozzle-to-substrate distance, the liquid flow rate, and the geometry of the spraying nozzle. By investigating the influence of the deposition temperature, information could be obtained on the formation mechanism of CaP coatings-and specifically the biologically interesting carbonate apatite phase-using the ESD technique. CaP coatings were not formed merely because of solvent evaporation; a chemical reaction was needed to synthesize the coatings. This reaction involved thermal decomposition of the organic solvent butyl carbitol into carbonate ions via formation of intermediate oxalate ions. The amount of carbonate incorporation, and consequently, the Ca/P ratios of the deposited coatings, was shown 1) to decrease with increasing nozzle-to-substrate distance, 2) to decrease with increasing liquid flow rate, and 3) to decrease by making use of a novel two-component nozzle geometry.  相似文献   
998.
In the process of developing global health informatics education, a common understanding of educational outcomes is required. Therefore, an educational framework for health informatics professionals is desirable to support student mobility, trans-national and borderless education. Nurses form a significant part of the health workforce and need to be properly educated for their roles in health informatics. To ascertain their perceptions of needs and priorities, we developed a web-based questionnaire and surveyed Australian nurses on the preferred knowledge/skills set for health informatics professionals. Among others, the questionnaire is based on the International Medical Informatics Association's (IMIA) set of recommendations on education and IMIA's scientific map. Benner's five levels of competencies were applied to measure the degree of competency required for each skill/knowledge. Altogether, 82 Australian nurses completed the questionnaire. The nurses' perceived degree of competency required for a total of 74 specific skills and knowledge in five skill categories is presented in this paper as well as the overall results for each of the five categories. Further, significant differences between the nurses' primary roles and primary interest in health informatics are discussed. The development of a comprehensive health informatics education framework needs to take into account nurses as well as other health professionals. Repeating the survey in other countries and for various professions is essential to develop an international educational framework.  相似文献   
999.
Recently nutrition support team (NST) has been established for the purpose of prevention of complications which are caused by nutrition disorders and reduction of the medical expenses. Although physical examinations and blood biochemical data had been used as the indexes evaluating nutritional of patients, they were not suitable for the evaluation for the short-term in-patient. On the contrary, serum albumin (ALB) has been wildly used as a nutritional marker. However, it is impossible to evaluate nutrition state for the short-term in-patient and acute phase disease patient accurately, because the plasma half-life is 21 days and it takes long time to detect the change in nutritional state by its value. Rapid turnover proteins (RTP), whose plasma half-life is shorter, has paid attention to evaluate nutritional state for the short-term in-patients and acute phase disease patients. Although, prognostic inflammatory and nutritional index (PINI) was considered as a useful maker for evaluating inflammatory and nutritional states using the concentrations of transthyretin (TTR), a RTP, alpha1-acid glycoprotein (alpha1-AG), a chronic inflammation marker, C reactive protein (CRP), a acute inflammation marker, and ALB, However, it has several pitfalls. We newly made serum amyloid A (SAA) index using SAA instead of CRP. When we compared SAA index with PINI in many diseases, it turned out that SAA index became a more effective index which reflected the patient condition than did PINI. As for this index, it is expected to be used by NST while further alternation may be needed.  相似文献   
1000.
This study was designed to develop a customized enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of Johne's disease (JD) in farmed deer. Two antigens were selected on the basis of their superior diagnostic readouts: denatured purified protein derivative (PPDj) and undenatured protoplasmic antigen (PpAg). ELISA development was based on the antigen reactivity of the immunoglobulin G1 (IgG1) isotype, which is a highly specific marker for mycobacterial disease seroreactivity in deer. Sensitivity estimates and test parameters were established using 102 Mycobacterium paratuberculosis-infected animals from more than 10 deer herds, and specificity estimates were determined using 508 uninfected animals from 5 known disease-free herds. A receiver-operated characteristic analysis determined that at a cut point of 50 ELISA units, there was a specificity of 99.5% and sensitivities of 84.0% with PPDj antigen, 88.0% with PpAg, and 91.0% when the antigens were used serially in a composite test. Estimated sensitivity was further improved using recombinant protein antigens unique for M. paratuberculosis, which identified infected animals that were unreactive to PPDj or PpAg. While 80% of animals that were seropositive in the IgG1 ELISA had detectable histopathology, the assay could also detect animals with subclinical disease. The test was significantly less sensitive (75%) for animals that were culture positive for M. paratuberculosis but with no detectable pathology than for those with pathological evidence of JD (>90%). When the IgG1 ELISA was used annually over a 4-year period in a deer herd with high levels of clinical JD, it eliminated clinical disease, increased production levels, and reduced JD-related mortality.  相似文献   
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