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41.
The objective of this study is to determine whether a normal fetal morphology ultrasound scan in women older than 35 years reduces the risk of aneuploidy. We reviewed the results of amniocentesis and second trimester sonogram in all women older than 35 years from 1991 to 1995. None had prior screening. We excluded fetuses with structural anomalies. We determined the sensitivity and specificity of minor markers in detecting Down syndrome and also determined the reduction in risk of a normal sonogram. Among the 2060 women older than 35 years giving birth during the study period, 16 (0.78%) delivered an infant with Down syndrome. Of the 16 fetuses, two had no prenatal testing or ultrasound, two had invasive testing but no second trimester sonogram, five had a normal sonogram and seven had one or more sonographic markers of Down syndrome. At least 17% of women older than 35 years did not participate in prenatal testing or ultrasound. Ultrasound detected Down syndrome with a sensitivity of 59% (95% confidence interval: 45–72%), a false‐positive rate of 10.6% (9.4–11.8%) and a positive predictor value of 1 in 9. The likelihood of having normal karyotype if the sonogram was normal was 0.46 (0.31–0.61). In women older than 35 years, a normal second trimester sonogram reduces the risk of Down syndrome by more than 50%. At least 17% of women older than 35 years do not participate in prenatal testing or ultrasound. 相似文献
42.
[背景 ]比较分析 88例不同年龄组急性脑梗死患者的病因、症状、体征及头部CT所见 .[病例报告 ]将 88例急性脑梗死患者分为老年组和非老年组 ,对发病因素、症状、体征和头部CT特点进行对比分析 ,发病因素中有高血压者占 6 4 % ,心脏病者占 2 3% ,糖尿病者占 2 5 % ,有短暂性脑缺血发作病史者占 30 % ,高脂血症者占 4 5 % ,吸烟者占 5 2 % ,有家族史者占 33% .非老年组中初发者多见 ,有头痛、头晕及偏身感觉障碍等症状者比老年组多见 ,而偏瘫、四肢瘫、构音障碍及意识障碍者则老年组多见 .头部CT示单梗塞灶者在非老年组多见 ,多梗塞灶、脑白质脱髓鞘及脑萎缩者在老年组多见 .[讨论 ]脑梗死病人因年龄不同 ,其发病因素、临床表现及头部CT所见有所不同 相似文献
43.
腮腺混合瘤(mixed tumor)是颌面部常见的良性肿瘤之一,但本例为高龄患者,且肿瘤重达4 600 g,国内外少见报道[1,2],现报告如下。患者女性,86岁,农民(住院号69133)。主因“左颌面部渐进性增大肿块40余年,”于1999年8月20日上午8时入院。入院体检,一般情况可,心、肺、腹部未见异常 相似文献
44.
宜昌市20年结肠镜检查大肠癌患病率回顾性分析 总被引:5,自引:0,他引:5
目的探讨该市大肠癌流行病学和临床特点。方法以所有结肠镜受检对象为研究群体,对大肠癌患病率、大肠癌患者性别、年龄、肿瘤部位进行统计分析;比较大肠癌临床症状与大肠癌患者年龄、肿瘤发生部位的关系。结果自1980年以来,大肠癌年度患病率呈非线性缓慢上升,男性大肠癌患病率7.1%;女性大肠癌患病率5.5%;在3个年限段(80年代、90年代和21世纪5年)大肠癌中位患病年龄分别为男53.5、56.7和59.0岁;女51.9、53.7和55.2岁。986例大肠癌中直肠癌691例,乙状结肠癌82例,降结肠癌18例,脾曲癌4例,横结肠癌37例,肝曲癌30例,升结肠、回盲部癌79例,大肠多发性癌45例。临床症状以便血为主,其次为腹痛、腹部包块和肠梗阻发生率较低,半数以上患者有不同程度贫血。结论该市大肠癌患病率和中位发病年龄呈缓慢上升,低于国内大肠癌高发区。大肠癌肿瘤发生部位有近移和多发趋势。便血是直肠癌主要症状,中老年患者便血发生率高于青年患者,但腹痛发生率低于青年患者。 相似文献
45.
Sociodemographic Differences in the Prevalence of Self-Reported Headache in Icelandic School-Children 总被引:1,自引:0,他引:1
Gúdrun Kristjánsdóttir R.N. M.Sc. Vivian Wahlberg R.N. Dr. Med. Sc. Professor 《Headache》1993,33(7):376-380
SYNOPSIS
The study considers the prevalence of headache experiences in a random national sample of 2140 Icelandic 11-12 and 15-16 year-old school-children. The study finds an overall 21.9% prevalence of "at least weekly" headache. The prevalence is significantly higher among younger children end among girls. The gender difference is found to be related to the fact that older boys have a markedly lower prevalence than younger boys. No gender difference is observed in the younger group. Social class interacts with gender, with the gender difference leveling out in the upper class. The frequency of headache experiences correlates with last months use of medication to relieve headache. The high overall prevalence of headache found in this study agrees with earlier findings, and is a matter of concern since little is being done to counter this problem of discomfort among school-children. 相似文献
The study considers the prevalence of headache experiences in a random national sample of 2140 Icelandic 11-12 and 15-16 year-old school-children. The study finds an overall 21.9% prevalence of "at least weekly" headache. The prevalence is significantly higher among younger children end among girls. The gender difference is found to be related to the fact that older boys have a markedly lower prevalence than younger boys. No gender difference is observed in the younger group. Social class interacts with gender, with the gender difference leveling out in the upper class. The frequency of headache experiences correlates with last months use of medication to relieve headache. The high overall prevalence of headache found in this study agrees with earlier findings, and is a matter of concern since little is being done to counter this problem of discomfort among school-children. 相似文献
46.
A comparison of 121 mature-age and 270 normal-age entrants who graduated from the University of Queensland Medical School between 1972 and 1987 shows that mature-age entrants are some 7 years older, are more likely to come from public (state) schools and less likely to have parents in professional/technical occupations. Otherwise, the two groups were similar in terms of gender, marital status, number of children, ethnic background and current practice location. The educational background of mature-age entrants prior to admission includes 44.6% with degrees in health-science areas and 31.4% with degrees in non-health areas. Reasons for delayed entry of mature-age entrants include late consideration of medicine as a career (34.7%), financial problems (31.4%), dissatisfaction with previous career (30.6%), poor academic results (19.8%), or a combination of the above factors. Motivations to study medicine include family influences (more so in normal-age entrants), altruistic reasons (more so in mature-age entrants) and a variety of personal/social factors such as intellectual satisfaction, prestige and financial security (similar for both groups) and parental expectations (more so in normal-age entrants). Mature-age entrants experienced greater stress throughout the medical course, especially with regard to financial difficulties, loneliness/isolation from the students and family problems (a greater proportion were married with children). While whole-course grades were similar in both groups, normal-age entrants tended to win more undergraduate honours/prizes and postgraduate diplomas/degrees, including specialist qualifications. Practice settings were similar in terms of group private practice, hospital/clinic practice or medical administration, but there was a greater proportion of mature-age entrants in solo private practice, and a smaller proportion in teaching/research. If given the time over, some two-thirds of both groups would choose medicine as a career. Reasons for job satisfaction include helping patients, intellectual stimulation and financial rewards. Reasons for dissatisfaction include pressure of work, red-tape/paperwork, 'doctor-bashing', long working hours, emotional strain, financial pressure, unfulfilled career expectations and irritation with trivial medical complaints. 相似文献
47.
儿童胫后神经刺激的体感诱发电位正常值及其特点 总被引:4,自引:0,他引:4
探讨儿童体感诱发电位的正常值。对30例8-14岁健康儿童记录和测量了刺激胫扣神经引起的脊髓和皮层SEPs正常值,并计算出胫后神经4 传导速度。结果1.SEPS各波潜伏期与身高均呈高度正线怀相关,与年龄,体重亦呈正相关,而潜伏期与年龄,体重的正相关是由身高引起的。2.P40-N20波间期与身高,年龄,体重均无显著相关关系。结论,SEPS潜伏期正常值应按其与身高的回归方程确定,P40-N20波间期正常 相似文献
48.
Effects of smoking and drinking on excretion of hippuric acid among toluene-exposed workers 总被引:1,自引:1,他引:0
Osamu Inoue Kazunori Seiji Takao Watanabe Haruo Nakatsuka Chui Jin Shi-Jie Liu Masayuki Ikeda 《International archives of occupational and environmental health》1993,64(6):425-430
Summary In order to investigate possible effects of smoking and drinking on the metabolism of toluence in occupational settings, 206 toluene-exposed men (mean age: 31.4 years) in shoemaking, painting, or surface-coating workshops together with 246 nonexposed control men (36.8 years) were studied for the time-weighted average intensities of exposure to toluene, hippuric acid concentration in shift-end urine samples, and the two social habits of smoking and drinking. The mean daily consumptions of cigarettes and ethanol were about 20 pieces and 10 g among smokers and drinkers, respectively. The geometric mean toluene concentration among the exposed subjects was about 20 ppm, with a maximum of 521 ppm. Regression analysis after classification of the subjects by smoking and drinking clearly demonstrated that the two social habits, when combined, markedly reduce the hippuric acid level in the urine of workers exposed to was a significant association between smoking and drinking habits, which hindered separate evaluation of the effects of the two habits on toluene metabolism. Comparison of the present results with the findings reported in the literature, however, suggested that the observed effects may be attributable to smoking rather than to drinking habits. 相似文献
49.
用一种可穿透紫外线的可溶性菌膜作为生物指示剂,检查紫外线的消毒效果。当紫外线剂量为12000μw·s/cm2时可杀灭99.9%以上金黄色葡萄球菌;50000μw·s/cm2可杀灭99.9%以上枯草杆菌芽孢。并且证明杀菌效力不完全取决于紫外线强度的高低,而照射剂量的大小在消毒效果中起关键作用。应用时根据不同消毒对象,调节照射时间,计算所需照射剂量,即可达到保证消毒质量的目的。应用新型生物指示剂检查紫外线消毒效果除简化操作程序外,还可以提高细菌回收的准确度及试验的重复性。 相似文献
50.
A. Molina-Carballo A. Munoz-Hoyos J.A. Martin-Garcia J. Uberos-Feritindez T. Rodriguez-Cabezas D. Acuna-Castroviejo 《Journal of pineal research》1996,21(2):73-79
Abstract: It seems clear that the pineal hormone, melatonin (N-acetyl-5-methoxytryptamine), is involved in the reproductive behavior of several animal species including humans. Moreover, several data also support a role for 5-methoxytryptophol (ML), another pineal hormone, in the control of sexual processes. To test the role of ML in human reproductive axis, 128 healthy children, 68 boys and 60 girls, were studied. Each of these groups was divided in three age subgroups of 6, 11, and 14 years. A single blood sample (0900 hours) was obtained from each subject to determine melatonin, ML, FSH, LH, estradiol (girls), and testoterone (boys) by RIA. Statistical analysis of the data included ANOVA-II (factor I: age, factor II: sex) and an analysis of covariance with age as covariate. A similar plasma melatonin concentration, with a significant decrease between 6 and 11 years, was found in boys and girls. Melatonin concentrations correlate well with initiation of the pubertal development in these children, although no sex differences were found. Concentrations of ML are approximately 50% of those of melatonin. In contrast to melatonin, ML levels show significant age and sex differences. Plasma ML concentration significantly increased in boys ( P < 0.001) and decreased in girls (P < 0.001) after 8 years of age. These results support the hypothesis that, besides melatonin, other pineal compounds such as ML may be involved in the maturation process in humans. The pineal indole ML may also be used as a marker of the different chronobiology in the pubertal development in boys and girls. 相似文献