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21.
Summary It has been suggested that inherited traits play a role in the development of osteoporosis by providing a background for the modulation of gene expression. In this study, we examine the influence of the different alleles of alpha2-HS glycoprotein (AHSG), a protein of the bone matrix, on quantitative estrogens, estrone and estradiol, and bone measures, bone area and density. Estrogens provide a protective effect against fractures in older women and were thus included in the analyses. Isoelectric focusing of AHSG from sera followed by immunoblotting was used to type 163 white post-menopausal women participating in a clinical trial of the effects of walking on bone loss. Plasma hormones were measured by a combination of extraction, column chromatography, and radioimmunoassay; bone measures on the dominant radius were determined with computerized tomography. Analysis of variance was done on estrogen and bone measures after controlling for the effects of age and body mass index. The two major alleles of AHSG result in three phenotypes, designated AHSG 1-1, AHSG 2-1, and AHSG 2-2. The AHSG 1-1 homozygote showed a decreased concentration of estradiol, the AHSG 2-2 homozygote showed an increased concentration, and the AHSG 2-1 heterozygote was intermediate (P=0.001). Estrone demonstrated a similar pattern in residual analysis although it did not reach statistical significance.  相似文献   
22.
文章系统地介绍了该院几年来解放思想,更新观念,加快医院改革的力度 和速度,在改革中求生存、求发展的具体措施(建立“业务部制”等)以及所取得的成效。  相似文献   
23.
本文对乡镇中,小学的交通噪声进行了调查研究,结果表明,在9:00~16:45时间内,中学的Leq值为80dB(A),L50为72dB(A),小学的Leq值为805dB(A),L50为73dB(A)。文章还对不同距离的噪怕衰减情况进行统计分析,并制订出乡镇中,小学教室内噪声不超过50dB(A)防护距离为120米,不超过45dB(A)防护距离为220米。  相似文献   
24.
L. Antonicelli    M.B. Bilò    S. Pucci    C. Schou  F. Bonifazi 《Allergy》1991,46(8):594-600
The efficacy of an air-cleaning device equipped with a high efficiency particulate air (HEPA) filter (without further avoidance measures) was studied in patients allergic to house dust mite. The effects of the air-cleaner on indoor Dermatophagoides sp. levels, symptom score and bronchial hyperresponsiveness in nine mite-allergic patients were assessed using a cross-over controlled study. No significant effect was demonstrated on indoor Dermatophagoides sp. levels when comparing the period of air-cleaner activity (2 months) with the control period (2 months). The Dermatophagoides sp. levels in the houses studied were lower than the risk level for asthmatic attacks, making it difficult to assess any effect on asthma; however, neither bronchial hyperresponsiveness nor rhinitis symptom score were changed by air-cleaner activity. During the trial period, however the mean level of Dermatophagoides sp. allergen in the houses changed spontaneously from 4.4 micrograms/g (mean level in the first 2 trial months) to 1.75 micrograms/g of dust (second 2 months) (P less than 0.05). Owing to this change, the mean rhinitis symptom score also decreased (P less than 0.05), even if no significant correlation was demonstrated (r = 0.4 P = 0.089). HEPA filter air-cleaners appear insufficient as substitutes for standard avoidance measures in mite allergic patients.  相似文献   
25.
目的:了解动静脉内瘘血栓形成的原因,提出防治措施。方法:81例维持性血液透析患有15例内瘘发生血栓形成。分析病因、性别、年龄、血压、血脂对血栓形成的影响。结果:在内瘘使用的早期(三年内)易发生血栓,内瘘血栓发生率为18.52%。老年、男性、糖尿病、血压低、血脂高的患内瘘易发生血栓.结论:定时监测血管通路,适量使用促红索,缓慢提高血红蛋白,恰当地应用抗凝治疗;减慢透析超滤速度,防止透后低血压;采取阶梯式穿刺法,透析后采取点状压迫,防止力量过大,压迫时问过长和对患及家属进行保护内瘘的宣教均是预防内瘘发生血栓的重要措施。  相似文献   
26.
Currently few subjective measures of Quality of Life (QoL) are available for use in developing countries, which limits their theoretical, methodological, and practical contribution (for example, exploring the relationship between economic development and QoL, and ensuring effective and equitable service provision). One reason for this is the difficulty of ensuring that translated measures preserve conceptual, item, semantic, operational, measurement; and functional equivalence (Herdman, M., Fox-Rushby, J., & Badia, X. (1998). Quality of Life Research, 7, 331), which is illustrated by an account of the translation, pre-piloting, and administration of a new individualised QoL measure, the Global Person Generated Index or 'GPGI'. The GPGI is based on the widely used Patient Generated Index (Ruta, Camfield, & Martin, (2004) Quality of Life Research, 13, 1545.) and offers many of the advantages of the participatory approaches commonly used in developing countries, with added methodological rigour, and quantitative outcomes. It was successfully validated in Bangladesh, Thailand, and Ethiopia, using quantitative and qualitative methods--open-ended, semi-structured interviews (SSIs), conducted immediately post-administration. Both the measure and method of 'qualitative validation' described later in the paper offer an exciting alternative for future researchers and practitioners in this field. The quantitative results suggest the GPGI shows cultural sensitivity, and is able to capture both the areas that are important to respondents, and aspects of life one would expect to impact on QoL in developing countries. There were strong correlation between scores from the GPGI and SSIs for the area of health, and moderate correlations for 'material wellbeing' (MWB)('Material wellbeing' refers to respondents' perceptions of their achievement in the areas of farming, debt reduction, assets, crops, livestock, job, land, property, and agriculture) and children. Weak to moderate correlations were observed between the Satisfaction with Life Scale and the GPGI; however, the highest coefficient was between the GPGI and the most conceptually similar item. Statistically significant differences were seen in GPGI scores between rich and poor, urban and rural respondents, and different countries. Health and material wellbeing scores, derived from the SSIs, also showed a linear relationship with GPGI scores, with a suggestion of curvilinearity at the higher levels, as predicted by a general QoL causal model. In conclusion, the GPGI has great potential for use in this area, especially when supported by extensive interviewer training, and supplemented with a cognitive appraisal schedule.  相似文献   
27.
目的研究溶酶体保护蛋白/组织蛋白酶A(protective protein/cathepsin A,PPCA)基因敲除小鼠听功能和耳形态学改变,探讨半乳糖唾液酸沉积症听力损害的病理生理机制。方法应用听性脑干反应(ABR)测试和颞骨连续切片,观察1月和2月龄的PPCA基因敲除纯合子(PPCA-/-)小鼠ABR反应阈和光镜下外耳、中耳及内耳形态改变,并以野生型(PPCA / )小鼠作对照。结果1月龄PPCA-/-小鼠ABR反应阈和耳形态无明显改变;2月龄时,短声和短音8、163、2 kHz反应阈较PPCA / 提高40~45 dB SPL,中耳黏膜增厚、听骨细胞囊泡化、变形和关节腔融合,血管纹增厚、螺旋神经节细胞、螺旋缘纤维细胞、前庭膜、基底膜及沿前庭阶外淋巴隙的间皮细胞囊泡化,但Corti器毛细胞及支持细胞正常。结论溶酶体保护蛋白/组织蛋白酶A缺乏可导致听力损害、中耳及耳蜗形态改变、中耳炎、听骨改变以及耳蜗螺旋神经节、血管纹、螺旋缘、前庭膜和基底膜等细胞的溶酶体储积,可能分别是传导性聋和感觉神经性聋的形成机制。  相似文献   
28.
Electroencephalogram (EEG) recordings were made from 26 pairs of monozygotic (MZ) and 26 pairs of dizygotic (DZ) adult male twins, before and after alcohol ingestion. After a baseline EEG and a light breakfast, 1.2 ml/kg of ethanol was given orally over 15 min and the EEG repeated four times at hourly intervals. Alcohol caused a significant drop in the percentage of beta waves (14-30 cycles/sec) during the 1st hr. For the percentage of beta waves in 38 pairs of twins with complete data, MZ twin beta-wave intraclass correlations (RMZ) ranged between 0.85 and 0.91 before and after alcohol, but the DZ intraclass correlations (RDZ) started at 0.54 and fell to 0.05 at 2 hr after alcohol before recovering to baseline levels. These correlations resulted in heritability estimates [2(RMZ-RDZ)] of 0.68 at baseline and 1.73 at 2 hr. A heritability of 1.43 was found for the 1st hr drop in percentage of beta waves (RMZ = 0.78, RDZ = 0.06). These unrealistically high heritabilities, due to RDZ's approaching 0.0, suggest a failure of assumptions in the linear twin model that was used. Also, these findings are similar to, but more exaggerated than, findings in resting EEG's and visually evoked EEG potentials of twins and are compatible with the influence of gene interactions.  相似文献   
29.
A diary method using household measures was employed to obtain dietary records in a large national prospective survey and a computer program, DIDO (Diet In Data Out), was designed for direct entry of the diaries. The accuracy of this computerized coding system was examined alongside that of the manual coding used for a similar diary in a previous wave, 7 years earlier, of the same survey. Accuracy was assessed by analysis of the errors in the coded and checked records by stringent re-checking of nominal 2% random subsamples of the diet diaries coded by each method. The mean time to code and check each of the 2086 7-day records in the whole survey using DIDO was 58 minutes (SD 30) compared with reported results of 1–4 hours for manual methods. The mean error rate of computerized coding and checking with DIDO was 2.3% (SD 2.1; range 0–8.9) per diary in the subsample. Correcting these mistakes made insignificant changes to the calculated mean energy and nutrient intakes for the subsample. The percentage of individuals changing to an adjacent third of nutrient distribution after correcting unambiguous errors ranged from none (for alcohol) to 11% (for carbohydrate and calcium intake). The mean error rate on a similar subsample of diaries from the earlier survey which had been coded manually was significantly higher at 5.9% (SD 4.1; range 0–17) per diary. Emphasis is laid on the importance, in coding, of dealing with ambiguities in the subjects' records, since this can affect the accuracy and the precision of the nutrient results obtained. We conclude that the DIDO coding method has the advantages of greater accuracy, speed, consistency and efficient data handling, and affords greater data accessibility for checking, compared with manual systems.  相似文献   
30.
医用透明质酸钠预防腹部手术后腹腔粘连的临床观察   总被引:9,自引:0,他引:9  
目的 观察医用透明质酸钠对预防腹部手术后腹腔粘连的作用。方法 136 0例腹部手术患者 ,关腹前于腹膜及腹腔创面涂抹医用透明质酸钠 (sodiumhyaluronate)凝胶剂 3~ 15ml,随访期间 ,2 3例患者获 2次手术探察的机会 ,观察腹腔粘连程度 ,并与同期未用透明质酸钠凝胶剂的 2 6例 2次手术患者作对比分析。结果观察组 :腹腔粘连Ⅰ级 11例 ,Ⅱ级 9例 ,Ⅲ级 3例 ,Ⅳ级 0例 ;对照组 :Ⅰ级 1例 ,Ⅱ级 5例 ,Ⅲ级 17例 ,Ⅳ级 3例。两组轻度粘连分别为 87%和 2 3% ;两组重度粘连分别为 13%和 77%。两组患者手术后腹腔内粘连情况比较 ,差异有显著意义 (P <0 0 1)。结论透明质酸钠凝胶对腹部手术后预防腹腔粘连具有明显效果。  相似文献   
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