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61.
相对湿度对空调环境至适温度影响的研究 总被引:1,自引:0,他引:1
本文研究空调室内相同温度(夏季:24℃,28℃:冬季:19℃;22℃)条件下相对湿度(分别为30~70%;85~95%)对至适温度的影响。以健康成年人为研究对象,以体温、皮温、皮温差、温热感和舒适感为观察指标。结果表明:空调室内气温相同时,皮温差、温热感、舒适感均随气湿不同而出现差异。夏季空调温度为28℃、气湿为85~95%时,皮温差(2.1℃)已超出生理至适范围,温热感(12.5%)和舒适感(0%)也随湿度增高而下降(P<0.01)。提出在制订空调至适温度卫生标准时,应考虑空气湿度对至适温度的影响。 相似文献
62.
S J Liu Q S Qu X P Xu Y T Liu S N Yin Y Takeuchi T Watanabe O Inoue M Yoshida M Ikeda 《American journal of industrial medicine》1992,22(3):313-323
A factory survey was conducted in three provinces in China from 1985 to 1989. The time-weighted average toluene concentrations in breathing zone air were monitored by diffusive sampling, whereas hippuric acid (HA) concentrations in shift-end urine samples were measured by high performance liquid chromatography (HPLC). Exposed workers (456 men and women) were those for whom toluene (up to 548 ppm toluene) accounted for greater than or equal to 90% of total exposure (by vapor concentration in ppm), whereas 517 nonexposed controls were recruited from the same factories or from factories of the same region. There was a linear correlation between the intensity of toluene exposure and HA concentration in the shift-end urine. Comparison of the results with findings in the literature shows that the toluene-induced increase in urinary HA concentration among workers in China is significantly smaller than the published values, whereas HA concentrations in urine samples from nonexposed controls are comparable to the levels previously reported. 相似文献
63.
本文着重检测了不同免疫缺陷的纯合子615-nu、615-bg、615-nu/bg、Ba1b/c-nu和表现型正常的杂合子615/PBI小鼠的巨噬细胞细胞毒活性、吞噬功能,并与它们的NK细胞活性和T、B细胞功能进行了对比分析。实验结果表明:这些不同免疫缺陷的615小鼠其相应的免疫缺陷的性质是确定的。615-nu、615-nu/bg、Ba1b/c-nu的巨噬细胞毒活性与615/PBI无明显差别,但吞噬指数较正常升高,而615-bg的巨噬细胞细胞毒活性和吞噬功能则都显著低于615/PBI的。 相似文献
64.
Wistar rats were divided into 8 groups:control, 300 ppm F, 130 ppm F, 300 ppm Al, 1200 ppm Al, 130 ppm Al + 130 ppm F. 300 ppm Al + 300 ppm F and 1200 ppm Al + 300 ppm F. The chemicals were mixed into the standard diet. The animals were fed on the diets for 12 weeks. Contents of F, Al, Ca and P in the blood (or serum) and humerus were determined at the end of 12 weeks. The results showed that the level of F in the blood and bone in the unadulterated F group was increased, especially F in the bone reached a level more than 10 times that of the control. In the 3 mixture groups, blood F and bone F were lowered, while blood F was restored to normal level, but bone F was not nevertheless, the results showed that Al was in antagonism to the absorption of F. In the unadulterated Al groups, blood and bone Al did not parallel with the amount of Al administered. The level of Al in the median Al group was higher than that of the high Al group. Taking the level of blood and bone Al as a measure, when different doses of Al were administered with F, in the low and median dosage of Al, F was in antagonism to Al absorption, but in case of high dosage of Al, F was in potentiation to Al absorption. In all the experimental groups serum P was elevated, but serum Ca was not disturbed. Bone Ca and P were decreased only in the 3 groups with unadulterated F as well as unadulterated and adulterated high dosage of Al. Mechanism of the nonlinearity of Al absorption vs Al dosage, as well as the dual effect of F on the absorption of Al was proposed. 相似文献
65.
用免疫组织化学ABC法,研究了降钙素基因相关肽(CGRP)免疫反应神经纤维在大鼠胆总管末端与十二指肠连接处的分布。大鼠的胆总管末端有较丰富的CGRP免疫反应神经纤维,它们多呈串珠(膨体)状,少数为无膨体的细长纤维。CGRP-IR纤维主要分布肌层及血管周围,在神经纤维的附近可见到含CGRP-IR阳性颗粒的肥大细胞。本实验为神经免疫调节机制的研究提供了形态学依据。 相似文献
66.
骨肉瘤增殖细胞核抗原(PCNA)表达及其与临床病理和预后的关系 总被引:3,自引:0,他引:3
应用单克隆抗体PC10免疫组方法半定量分析了增殖细胞核抗原表达与50例骨肉瘤患者预后的关系。PCNA阳性级者预后差,其中半定量分级与骨肉瘤术后生存期呈显著负相关。PCNA表达与骨肉瘤组织学分级及骨样组织分化程度相关。 相似文献
67.
目的 探讨新生儿手术体位的摆放方法,利于术野的暴露和手术的顺利完成。方法 自制新生儿手术体位摆放辅助物品,用于46例出生2h至28d需仰卧位、侧俯卧位、截石卧位及侧卧位手术患儿的体位摆放。结果 术野暴露充分,术中患儿呼吸、循环正常,关节、神经功能完好,皮肤无擦伤,均顺利完成手术。结论 针对新生儿特点,合理摆放体位,有利于确保手术成功。 相似文献
68.
Objective:To investigate the relationship between antibiotic administration and the changes in bacteriological profile in a burn unit. Methods: The data of consumption of different kinds of antibiotics, including total antibiotic consumption [expressed as the number of defined daily doses (DDD)] as well as pathogen identification, were collected in a 8-year period. The constituent ratios of different kinds of antibiotics in total antibiotic consumption to isolation rates of various species of bacteria were calculated, and their correlation was analyzed. Results: Within this period, it was found that the aminoglycosides and first generation cephalosporins were used less frequently, while the polypeptides, carbopenem and macrolides were used proportionally more. At the same time, the isolation rates of Staphylococcus aureus, Acinetobacter sp, Enterobacter cloacae, Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus were gradually increased. The constituent ratios of predominant pathogens were correlated to the different kinds of antibiotics consumption in the burn unit. Conclusion: The results suggested that the consumption of different antibiotics was closely related to the trends of emergence of bacterial isolates from infected burn wounds. The result might imply that to regulate the administration of certain antibiotics might help decrease the emergence of certain pathogenic bacteria in burn infections. 相似文献
69.
目的:探讨适合睫状体缝合复位术病人的护理方法。方法:对34例(34只眼)因外伤致睫状体分离和脱离导致低眼压,随后行睫状体缝合复位术的病人进行观察和护理。结果:32只眼术后1周至6个月眼压恢复正常,其中5只眼术后2~5个月内分别进行第二次手术或氩离子激光光凝而痊愈。视力改善者21例,无变化者13例。结论:睫状体缝合复位术是治疗外伤性睫状体分离和脱离的有效方法。术前行超声生物显微镜(UBM)检查、术后密切观察眼压变化并给予正确处理、做好心理护理和出院指导是确保手术成功的重要措施。 相似文献
70.
胃癌高系家族成员胃蛋白酶原C基因多态性及其诊断意义的探讨 总被引:1,自引:0,他引:1
采用限制性酶切片段长度多态性分析法,检测在胃癌高发区庄河检出的19例胃癌高系家族成员胃蛋白酶原C基因多态性,发现三种常见片段及一种稀有片段。对其中4例携带稀有片段的受检者进行了胃镜追踪观察,2.5年后发现1例早期胃癌。本文对此作了初步探讨。 相似文献