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63.
为探讨新婚前后人群对避孕方法(特别是紧急避孕方法)的知识、态度和使用以及新婚前后人群对紧急避孕的需求及对推广EC的意愿的建议。采用描述性流行病学研究方法,以郑州市新婚学校为研究现场,直接收集第一手数据。采用EPI INF6.04软件包,和SPSS7.5 FOR WINDOW95软件包,进行数据处理、统计与分析。统计分析的主要指标有:频数分布,单因素分析,logistic多元回归分析等。结果平均年龄26.41岁,女性占49.4%。在第一次同房时,仅有46.4%的人使用过避孕方法。第一次同房时最常用的避孕方法是避孕套(76.1%)。在女性应答者中,25岁以下开始同房者占76.6%,有9.3%的人有过人工流产史。88.2%的人每周有1~6次同房。有43.2%的人听说过EC方法,有35.9%的人听说过紧急避孕片,有29.9%的人知道使用EC片有时间限制,有24.7%的人听说过上环可作为紧急避孕方法,有17.4%的人知道上环紧急避孕方法有时间限制。仅有12.9%的人使用过某种事后避孕方法,其中有事后3天内使用者占82.0%。92.6%的人赞成开展EC教育。73.7%的人认为,应在未婚青少年中开展EC教育。80.7%的人认为,在本单位进行EC教育是可行的。应答者认为,最易的接受的EC教育形式依次为:阅读材料(40.4%),录相(20.6%)和讲课(15.7%)。认为EC的最可靠的信息来源 相似文献
64.
The purpose of this study was to assess, in subjects with low back pain, the changes and their permanence in muscular performance after a 3 month progressive physical exercise program. Ninety subjects with chronic low back pain participated in the study. The study design was controlled and it was carried out in three groups: intensive training, home exercise, and control group. Isometric and dynamic muscle strength of the trunk and lower limb were measured, at the beginning of the study and after the 3 months exercise program, and then during each of the follow-up sessions. The Oswestry Index and back pain intensity were also determined. Both exercise groups received benefit from the progressive exercise program. Their muscular performance improved and their back pain intensity decreased significantly. Among the home exercise group, the Oswestry Index also changed positively. The results demonstrate that the home exercise program could be as effective as the intensive training program in increasing muscle strength, as well as decreasing back pain and functional disability among low back pain patients with mild functional limitations. 相似文献
65.
Twenty-four-hour records of arterial pressure (AP), heart rate(HR), oral temperature (OT) and physical and mental performancewere obtained in air traffic controllers during morning (n=16),afternoon (n=17) and night (n=19) shifts. Data were analyzedby the cosinor method. The results obtained during the morningshift were as follows (mesor/amplitude/;acrophase): systolicAP (mm Hg)113.6/10.0/16:03 h; diastolic AP71.1/8.215:19h; mean AP85.6/8.8/15:41 h; HR (beats/min)77.5/8.9/16:00h; OT (dg C)36.71/0.21/15:49 h; right-hand grip strength(kg)49.8/2.0/17:43 h; left-hand grip strength46.1/2.0/16.08h; mental performance (calculations/min)14.9/1.1/16:39h. During the night shift either no change of the circadianacrophases (HR, right-hand grip strength) or acrophase delaysranging from about 2 h (systolic AP, OT, mental performance)up to 3 h (diastolic and mean AP, left-hand grip strength) wereobserved. Our data suggest that the shift system studied doesnot significantly alter the circadian rhythms, and does notinduce a desynchronization, particularly as concerns arterialpressure and oral temperature. 相似文献
66.
Summary A comparative study was undertaken to investigate the application of a specially adapted microsurgical Neodymium Yag Laser system with a wavelength of 1,319 m and a CO2 laser system for laser assisted microvascular end-to-end anastomosis (LAMA) of the rat femoral artery. Conventionally sutured anastomoses served as controls. Postoperative investigations included patency tests, light microscopy and tensile strength measurements. Both laser systems seem to be equally suitable for LAMA: The patency rates do not differ from those of sutured anstomoses and formation of microscopically small aneurysms occurred predominantly in control animals and only once in laser groups. The clamp time needed for LAMA was half the time that was needed for sutured anastomoses. Wound healing in all groups was similar with less fibrotic reactions and less foreign body granulomas in laser groups. At all intervals tensile strength was significantly higher for sutured anastomoses while differences between the CO2- and the ND: Yag-laser groups were not statistically significant. Potential applications in urology include microvascular anastomoses in erectile dysfunction, pediatric and reconstructive urology.Contains parts of a dissertation 相似文献
67.
Physical loading and performance as predictors of back pain in healthy adults A 5-year prospective study 总被引:4,自引:0,他引:4
Urho M. Kujala Simo Taimela Tero Viljanen Helena Jutila Jukka T. Vitasalo Tapio Videman Michele C. Battié 《European journal of applied physiology》1996,73(5):452-458
We investigated muscle strength, aerobic power, and occupational and leisure-time physical loading as predictors of back pain in a 5-year follow-up study. A cohort of 456 adults aged 25, 35, 45 and 55 years, free of back pain, participated in measurements of anthropometric characteristics, aerobic power and muscle strength characteristics at baseline. The subjects' levels and types of physical activity and occupational physical loading were also determined. At 5 years after the baseline examinations 356 of these subjects (78.1 %) were reached by mail, and 262 of them (73.6%) properly completed and returned a questionnaire including a detailed back pain history for the 5 years following the baseline measurements. Of this number 56 subjects (21 %) who reported back pain ( > 30 on a scale from 0 to 100) and functional impairment during the 5-year follow-up composed the marked back pain group. Other subjects (n = 71, 27%) noting lesser symptoms were included in the mild back pain group; 135 subjects (52%) reported having had no back pain. The subjects with marked back pain were on average taller than the subjects without back pain, while no such difference was found in body mass. Heavy occupational musculoskeletal loading (P = 0.005) and high general occupational physical demands (P = 0.036) predicted future back pain. Leisuretime physical activity, aerobic power or muscle strength characteristics were not predictive of future back pain. 相似文献
68.
本文研究了骨水泥三种不同临床使用方法所形成的内部气泡结构状态,测定了骨水泥的抗压强度、收缩率、疲劳强度、变形积累量等物理机械性能,以及关节固定强度,用气泡状态解释了不同临床使用方法对骨水泥性能及固定强度所带来的各种影响。 相似文献
69.
Alcohol and the Psychophysiological Detection of Deception 总被引:1,自引:0,他引:1
Psychophysiological detection of deception examinations were conducted on 40 subjects. Of these, 32 were “guilty” of a mock crime and 8 were innocent. Sixteen guilty subjects committed the crime while intoxicated and the remaining 16 committed the crime sober. These two groups of guilty subjects were subdivided such that half of each group was examined with the polygraph while intoxicated and the other half was examined while sober. Two questioning techniques were used in the examination, a Control Question Test and the Guilty Knowledge Test. Measures of skin resistance, heart rate and respiration were recorded. The principal findings were that alcohol intoxication during the crime reduced detectability with detection scores derived from the measurement of skin resistance responses on the Control Question Test and on the Guilty Knowledge Test. The analyses of guilt/innocent classifications, based on the detection scores, showed these classifications to be affected by alcohol intoxication. 相似文献
70.
探索了磷酸四钙(Ca4(PO4)2O,TTCP)的制备,并合成了磷酸钙骨水泥(CPC),对CPC固化时间、引起浸泡液pH值的变化、抗压强度、产物物相组成及微观结构进行了研究。结果表明:在真空条件下、1500℃下煅烧6h可制得TTCP,并含有少量CaO。CPC初凝时间为4min、终凝时间为15min,浸泡1d和7d后的抗压强度分别为20MPa和35MPa,浸泡液的pH值在6.4~8.9之间变化,这些性能均符合临床用CPC的性能要求。CPC水化产物为片状或针状羟基磷灰石(Ca5(PO4)3OH,HA),相互交错呈连续分布的网状结构,这种结构有利于材料强度的提高。实验研制的CPC材料可用于骨缺损的修复治疗。 相似文献