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11.
For the treatment of infectious diseases, cancer and allergy, the directed induction of an appropriate immune response is the ultimate goal. Therefore, with the development of pure, often very small proteins, peptides or DNA by molecular biology techniques, the research for suitable adjuvants or delivery systems became increasingly important. Particle formulations are made of a variety of materials, including lipids, proteins or amino acids, polysaccharides, polyacrylic substances or organic acids. Microparticles serve as vehicles and provide a depot for the entrapped or coupled antigen. The release occurs in a pulsatile or continuous manner, a feature, which is well controllable for many particulate systems. Particles attract antigen presenting cells to the administration site, thereby guaranteeing the efficient presentation of the antigen to the immune system. Importantly, particles also protect the entrapped substance. This is especially necessary after oral application to avoid gastric or tryptic breakdown. In this article, the design and construction of different antigen delivery systems and their immune effects, with special focus on the suitability for allergy treatment, are discussed.  相似文献   
12.
Lumbar disc syndrome in Finland.   总被引:11,自引:1,他引:10       下载免费PDF全文
The prevalence of lumbar disc syndrome (herniated disc or typical sciatica) and its consequences in terms of disability, handicap, and need for medical care were studied as part of the Mini-Finland Health Survey. A sample of 8000 persons representative of the Finnish population aged 30 or over was asked to come for examination, and 7217 (90%) participated. A diagnosis of lumbar disc syndrome based on medical history, symptoms, and standardised physical examination was made for 5.1% of the men and for 3.7% of the women. Half of these patients were assessed to be in need of medical care, over 80% of which was considered to be adequately met. One third of all patients with lumbar disc syndrome had been previously hospitalised for that syndrome, and one fifth of the patients had undergone lumbar surgery. At least slight disability was found in almost 60% of the patients, though severe functional limitations were rare. About 6% of the population's work disability was estimated to be attributable to lumbar disc syndrome.  相似文献   
13.
The exposure of homeothermic animals to a cold environment leads to a powerful activation of orexigenic signalling which is accompanied by molecular and functional resistance to insulin-induced inhibition of feeding. Recent evidence suggests that AMPK participates in nutrient-dependent control of satiety and adiposity. The objective of the present study was to evaluate the effect of cold exposure upon the molecular activation of AMPK signalling in the hypothalamus of rats. Immunoblotting demonstrated that cold exposure per se is sufficient for inducing, on a time-dependent basis, the molecular activation of the serine/threonine kinase AMP-activated protein kinase (AMPK) and inactivation of the acetyl-CoA carboxylase (ACC). These molecular phenomena were accompanied by resistance to nutrient-induced inactivation of AMPK and activation of ACC. Moreover, cold-exposure led to a partial inhibition of a feeding-induced anorexigenic response, which was paralleled by resistance to insulin-induced suppression of feeding. Finally, cold exposure significantly impaired insulin-induced inhibition of AMPK through a mechanism dependent on the molecular cross-talk between phosphatidylinositol-3(PI3)-kinase/Akt and AMPK. In conclusion, increased feeding during cold exposure results, at least in part, from resistance to insulin- and nutrient-dependent anorexigenic signalling in the hypothalamus.  相似文献   
14.
This review addresses the current state of knowledge in oral sensorimotor therapy for children with neurological impairments and ingestive problems. Comprehensive assessment of the child with dysphagia looks at the interaction of oral performance and growth. These domains include eating efficiency, oral-motor skills, oral sensory evaluation, classification of the severity of an eating problem, interaction of respiration and ingestion, aspiration, positioning for feeding, social skills assessment, careload and assessment technologies. Oral sensorimotor therapy improves eating but not drinking skills in children 3–12 years of age. Weight gain is sufficient so that children maintain their growth channel but they do not show catchup growth. Many factors thought to contribute to better ingestive performance need further study, such as jaw and lip control in association with drinking. The earliest possible identification of infants at risk for eating impairments needs to be rigorously pursued. Such an approach offers hope that the later growth deterioration now seen in children with eating impairments may be prevented. Finally, the effect of positioning and the use of eating equipment to promote self-feeding need further study.  相似文献   
15.
As part of an ongoing epidemiologic study, the death rate and causes of death during 1975 through 1984 were determined in Pima Indians who resided in the Gila River Indian Community (GRIC) in 1965 and later. Death certificates were available for 677 of the 681 deaths. In 78% of the deaths, the underlying cause recorded on the death certificate agreed with the cause determined after review of all available relevant records. The age- and sex-adjusted average annual death rate for the GRIC population (1639/100,000) was 1.9 times (95% CI 1.7-2.0) the 1980 rate for the U.S. all races (878/100,000). In Pima males, whose death rate was substantially higher than that of Pima females, the age-adjusted death rate was 2.3 times that in U.S. males, all races. Moreover among males 25-34 years of age, the Pima death rate was 6.6 times that for the U.S. all races. Diseases of the heart and malignant neoplasms caused 59% of U.S. deaths in 1980, but only 19% of GRIC deaths. By contrast, the age- and sex-adjusted mortality rate in the GRIC Pima was 5.9 times the rate of the U.S. all races for accidents, 6.5 times for cirrhosis, 7.4 times for homicide, 4.3 times for suicide, and 11.9 times for diabetes. Tuberculosis and coccidioidomycosis were important causes of death in the Pima, for whom infectious diseases was the tenth leading cause of death. The findings indicate that programs to improve the adverse mortality experience of the GRIC population should emphasize factors related to fatal accidents, alcoholic cirrhosis, homicide, suicide, diabetes mellitus, and infectious diseases. Young Pimas, especially the males, should be the primary focus of such preventive efforts. These findings and recommendations probably apply to many Native American populations.  相似文献   
16.
Unrealistic weight-loss goals may impede the success of weight-loss attempts. The aim of this study was to examine the frequency of unrealistic goals and their association with other patient characteristics at the start of a weight-loss program. For patients with a body mass index (calculated as kg/m2) of 30 to 35, 35 to 40, or 40 to 50, medically advised weight-loss goals were set at 10%, 15%, and 20% of current weight, respectively. Personal weight-loss goals exceeding the medically advised goal by >50% were considered unrealistic. Obesity-related beliefs were measured by the “Obesity Cognition Questionnaire” and the eating-behavior self-efficacy scale of the “Obesity Psychosocial State Questionnaire.” From September 2003 until March 2006, 90 patients were enrolled in the study, 26 men and 64 women, with a mean age of 43 years (range=18 to 68 years) and body mass indexes ranging from 30 to 50. Unrealistic goals were observed in 49% of the patients and were more frequent in younger patients (P=0.03), in patients attributing their obesity to physical causes (r=0.35, P=0.001), and in patients not attributing their obesity to behavioral causes (r=−0.28, P=0.008). This study confirms that discrepancies in weight-loss goals between obese patients and professionals occur frequently. Because unrealistic goals can hamper long-term outcomes of weight-loss programs, better outcomes could possibly be achieved by addressing unrealistic weight-loss goals before treatment.  相似文献   
17.
BACKGROUND: Improvement in aerobic capacity and reduction in blood pressure after Tai Chi exercise programs in persons with coronary heart disease (CHD) or with CHD risk factors have been reported. Self-efficacy has been shown to be a consistent predictor of behavioral outcomes, now being applied to Tai Chi exercise. AIM: To assess the utility and appropriateness of existing tools measuring aspects of Tai Chi exercise self-efficacy (TCSE) in a new population, ethnic Chinese with CHD risk factors. Specific objectives were: (1) examine acceptability and feasibility; (2) determine score distributions; (3) assess the reliability and known-groups validity; (4) translate tool into an equivalent Chinese version and determine if there were any differences between ethnic Chinese and non-Chinese. METHODS: Following a review of the literature, two existing tools used with Caucasians were found and modified; a 9-item exercise self-efficacy tool developed by Resnick and Jenkins [Resnick B, Jenkins LS, Testing the reliability and validity of the Self-Efficacy for Exercise scale. Nurs. Res. 49(3) (2000) 154-159], and a 3-item tool developed by Li et al. [Li F, McAuley E, Harmer P, Duncan TE, Chaumeton NR, Tai Chi enhances self-efficacy and exercise behavior in older adults. J. Aging Phys. Act. 9 (2001) 161-171] to assess gradations of the challenge to perform Tai Chi among elderly populations. The modified TCSE tool was translated into Chinese and back-translated. A pilot study was conducted to pre-test the modified 14-item TCSE tool in ethnic Chinese and non-Chinese. RESULTS: A total of 18 subjects (mean age = 60 years, S.D. = 18.4) participated. Seven subjects (39%) identified themselves as ethnic Chinese. Ten subjects (56%) had experience performing Tai Chi, ranging from 3 months to 17 years (mean = 5.0 years, S.D.=5.0). Half of the subjects reported having a history of hypertension (n = 9, 50%), while nearly one-third reported having high cholesterol (n = 5, 28%). No significant difference in TCSE mean scores was found between ethnic Chinese and non-Chinese (p > 0.05). Internal consistency estimates were very high (TCSE Barriers, r = 0.95; TCSE Performance, r = 0.97). A statistically significant difference was found in the TCSE mean scores between Tai Chi practitioners and non-practitioners (TCSE Barriers, t = -3.3, p = 0.01; TCSE Performance, t = -2.7, p = 0.03), with Tai Chi practitioners reporting higher self-efficacy; thus providing initial evidence of known-groups validity. CONCLUSIONS: Measurement of self-efficacy to overcome barriers to Tai Chi exercise (TCSE Barriers) and self-efficacy to perform Tai Chi (TCSE Performance) functioned well in this sample. The acceptability and feasibility of this tool was established and known-groups validity was confirmed. Further research using this tool among ethnic Chinese with CHD or CHD risk factors, including those with less than high school education or low literacy, is recommended as the next step in development of TCSE.  相似文献   
18.
19.
To extend the signal longevity of magnetically excited spins in flowing fluids while in a state of global coherent free precession (GCFP), a refocusing radiofrequency (RF) pulse and bipolar gradient waveforms were combined with the GCFP sequence. The data demonstrate that RF refocusing in the presence of flowing blood is possible, but the improvement in signal amplitude depends on the static magnetic field homogeneity along the direction of motion and the displacement of the spins between the excitation and the RF refocusing pulse, as well as displacement during subsequent RF refocusing pulses. The least amount of phase dispersion and thus the longest lasting signal is obtained with the shortest echo spacing where only one line of data is recorded between two RF refocusing pulses. This approach was successfully used in a phantom and in vivo to image fast and slow blood flow. Depending on the experimental conditions, signal persistence is improved significantly compared to playing the same sequence without RF refocusing, but the improvement is limited by the product of blood flow velocity and the time between RF refocusing pulses.  相似文献   
20.
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