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991.
 This study was conducted to clarify the seasonal difference in body temperature in summer and winter, and to document the thermal environment of the elderly living in nursing homes. The subjects were 57 healthy elderly people aged ≥63 years living in two nursing homes in Japan. One of the homes was characterized by subjects with low levels of activities of daily living (ADL). Oral temperatures were measured in the morning and afternoon, with simultaneous recording of ambient temperature and relative humidity. Oral temperatures in summer were higher than in winter, with statistically significant differences (P<0.05) of 0.25 (SD 0.61) °C in the morning and 0.24 (SD 0.50) °C in the afternoon. Differences between oral temperatures in summer and winter tended to be greater in subjects with low ADL scores, even when their room temperature was well-controlled. In conclusion, the oral temperatures of the elderly are lower in winter than summer, particularly in physically inactive people. It appears that those with low levels of ADL are more vulnerable to large changes in ambient temperature. Received: 28 March 1996 / Accepted: 12 November 1996  相似文献   
992.
Mucosal immunity and vaccination   总被引:7,自引:0,他引:7  
Abstract The gut mucosal immune system is a critical component of the body's defense against pathogenic organisms, especially those responsible for enteric infections associated with diarrhoeal disease. Attempts to vaccinate against infections of mucosal tissues have been less successful than vaccination against systematic infections, to a large extent reflecting a still incomplete knowledge about the most efficient means for inducing protective local immune responses at these sites. Secretory IgA (SIgA) is the predominating immunoglobulin along mucosal surfaces, and SIgA antibodies generated in gastrointestinal, respiratory or genito-urinary mucosal tissues can confer protection against infections affecting or originating in these sites. An efficacious intestinal SIgA immunity-inducing oral vaccine against cholera has been developed recently, and development of oral vaccines against other enteric infections such as those caused by enterotoxigenic Escherichia coli, Shigella and rotaviruses is in progress as well. Based on the concept of a common mucosal immune system through which activated lymphocytes from the gut can disseminate immunity to other mucosal and glandular tissues, there is currently also much interest in the possibility of developing oral vaccines against infections in the respiratory and urogenital tracts. However, the large and repeated antigen doses often required to achieve a protective immune response still makes this vaccination approach impractical for many purified antigens. There is, therefore, a great need to develop strategies for enhancing delivery of antigen to the mucosal immune system as well as to identify mucosa-active immunostimulating agents (adjuvants). These and other aspects of mucosal immunity in relation to immunization and vaccine development are discussed in this short review article.  相似文献   
993.
One of the major effects of fluoride on oral bacteria is a reduction in acid tolerance, and presumably also in cariogenicity. The reduction appears to involve transport of protons across the cell membrane by the weak acid HF to dissipate the pH gradient, and also direct inhibition of the F1F0, proton-translocating ATPases of the organisms, especially for Streptococcus mutans. This direct inhibition by fluoride was found to be dependent on aluminum. The dependence on aluminum was indicated by the protection against fluoride inhibition afforded by the Al-chelator deferoxamine and by loss of protection after addition of umolar levels of Al3+, which were not inhibitory for the enzyme in the absence of fluoride. The F1 form of the enzyme dissociated from the cell membrane previously had been found to be resistant to fluoride in comparison with the F1F0 membrane-associated form. However, this difference appeared to depend on less aluminum in the F1 preparation in that the sensitivity of the F1 enzyme to fluoride could be increased by addition of umolar levels of Al3+. The effects of Al on fluoride inhibition were apparent when enzyme activity was assayed in terms of phosphate release from ATP or with an ATP-regenerating system containing phosphoenolpyruvate, pyruvate kinase, NADH and lactic dehydrogenase. Also, Be2+ but not other metal cations, e.g. Co2+, Fe2+, Fe3+, Mn2, Sn2+, and Zn2+, served to sensitize the enzyme to fluoride inhibition. The differences in sensitivities of enzymes isolated from various oral bacteria found previously appeared also to be related to differences in levels of Al. Even the fluoride-resistant enzyme of isolated membranes of Lactobacillus casei ATCC 4646 could be rendered fluoride-sensitive through addition of Al3+. Thus, the F1F0 ATPases of oral bacteria were similar to E1E2 ATPases of eukaryotes in being inhibited by Al-F complexes, and the inhibition presumably involved formation of ADP-Al-F inf3 sup- complexes during catalysis at the active sites of the enzymes.  相似文献   
994.
Summary Iron chelators of different physicochemical properties were studied for their ability to donate iron in vitro to uninduced K562 cells, human bone marrow cells and purified human erythroblasts. To a large extent uptake was found to be related to lipophilicity and those chelators able to deliver iron to the cells in significant amounts were also able to deliver iron to ferritin and haem. Some differences in the distribution of iron delivered was observed but no chelator showed exclusive delivery to or rejection of a particular cellular iron compartment. Several chelators could probably substitute for transferrin and be used to probe metabolic events subsequent to iron removal from transferrin. Two chelators which were excellent iron donors were also found to cause considerable inhibition of iron incorporation into haem from transferrin. The implications of this for in vivo toxicity are briefly discussed.  相似文献   
995.
996.
Objectives: To describe the clinical health status and subjective oral health status of older adults from minority ethnic communities resident in South East England. Design: Cross sectional survey incorporating a clinical examination and a questionnaire assessment of subjective oral health status. Setting: Community groups working with individuals from minority ethnic communities. Subjects: A total of 540 individuals from 7 minority ethnic communities. Measures: Clinical assessment of oral health status using BASCD criteria. Assessment of oral symptoms and impact experienced together with satisfaction with oral status, by structured questionnaire. Results: On all measures of clinical health status the participants were healthier than a comparison group based on data from the Adult Dental Health Survey. The participants expressed high levels of subjective oral symptoms. Levels of satisfaction were lower than those found in the Adult Dental Health Survey. There was evidence of some variation across minority ethnic communities in clinical and subjective oral health status. Conclusions: Approximately 20% of the 540 adults from minority ethnic communities resident in the South East of England surveyed were relatively fit orally. They experienced a great many oral symptoms, and in approximately 30% of individuals these were sufficient to interfere with their quality of life. Ethical approval: The research described in this paper was approved by the Ethics committee of King's College London.  相似文献   
997.
摘要 目的:回顾性对比经胸乳入路、经口腔前庭入路两种入路方式治疗甲状腺微小乳头状癌(PTMC)的疗效。方法:回顾性分析南方医科大学附属南海医院甲状腺血管外科2019年1月-2021年6月期间接收的141例单侧PTMC患者的临床资料。按照入路方式的不同将患者分为A组(n=83,经胸乳入路)和B组(n=58,经口腔前庭入路),对比两组患者的创伤应激指标、手术相关指标、美容满意度、并发症及随访预后情况。结果:B组的手术时间长于A组,中央区淋巴结清扫数目多于A组,术后第1 d引流量、术中出血量少于A组,术后第1 d颈部VAS评分、切口总长度小于A组,术后住院时间短于A组(P<0.05)。术前、术后2 d,两组白细胞计数(WBC)、C反应蛋白(CRP)、前列腺素E2(PGE2)、皮质醇(Cor)水平组间对比无差异(P>0.05);两组术后2 d,WBC、PGE2、CRP、Cor水平均较术前升高(P<0.05)。B组的美容满意率高于A组(P<0.05)。两组并发症发生率组间对比无差异(P>0.05)。术后随访1年,两组患者的死亡率、复发率、颈部淋巴结转移率均为0,组间对比无差异(P>0.05)。结论:经口腔前庭入路可获得与经胸乳入路治疗PTMC相当的手术疗效,但经口腔前庭入路清除中央淋巴结数目更多,创伤小,术后疼痛轻,同时美容满意度更高。  相似文献   
998.
朗格罕细胞(langerhanscel,LC)是一种骨髓来源的免疫活性细胞,具有呈递抗原,诱导免疫反应的功能。口腔粘膜的复层鳞状上皮中亦有LC分布,它们是口腔粘膜防御体系的组成部分。本研究运用ATP酶组织化学方法和电镜技术,对25例人的口腔粘膜标本中的LC的形态、结构及数量分布进行观察,结果提示,在口腔粘膜的上皮中,LC主要分布于上皮的基底部,并且趋于环绕结缔组织乳头排列,LC的数量也因部位不同而有显著差异  相似文献   
999.
The relationship between oral health status and well-being of community dwelling frail elders was studied through questionnaires delivered to and filled out by 592 elders receiving home delivered meals. Oral status covered oral function, dental problems, oral hygiene practices and appliance use in the sample. Oral status was measured in a sub sample of 50 subjects given an oral examination, using the criteria above and soft tissue status. Plaque, calculus, and caries were measured in dentate subjects of the sub sample. Well-being was measured using standardised scales. The results indicate that oral status was related to well-being status.  相似文献   
1000.
Abstract Viable counts and activities of sulfate-reducing bacteria were determined in the oral cavities of 12 healthy volunteers. Of these, 10 harboured viable sulfate-reducing bacteria populations. Six separate sites were sampled: the posterior tongue, anterior tongue, mid buccal mucosa, vestibular mucosa, supragingival plaque and subgingival plaque. Sulfate-reducing bacteria occurred in all areas, with the highest incidence in supragingival plaque. Viable counts and sulfate-reducing activities in each of the regions varied from 0 to 108 cfu (g wet weight)−1 and from 0 to 50 nmol (g wet weight) −1 h−1, respectively. As sulfate-reducing bacteria can be detected in the oral cavity, they may potentially be involved in terminal oxidative processes carried out by the microflora of the mouth.  相似文献   
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