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91.
92.
NOV蛋白免疫反应阳性神经元在鲢、鸡和几种哺乳动物脑的比较发育 总被引:1,自引:0,他引:1
目的:研究鲢、鸡、牛、犬和大鼠脑肾母细胞瘤过度表达基因(nov)蛋白免疫反应阳性神经元的比较发育。方法:免疫组织化学技术。结果:低等脊椎动物鲢脑仅有少量NOV蛋白免疫反应阳性神经元,分布于延髓的一些核团、丘脑前核、丘脑后核、下丘脑背侧核、下丘脑外侧核。鸡脑NOV蛋白免疫反应阳性神经元除广泛分布于脑干外,小脑、间脑和大脑纹状体的多数脑区阳性神经元亦较多。哺乳动物牛、犬和大鼠脑NOV蛋白免疫反应阳性神经元广泛分布,脑干、小脑、间脑和大脑都检测到强烈阳性信号。结论:nov基因在从低等脊椎动物到高等脊椎动物的进化过程中非常保守,提示它在脑神经元生长、分化及正常生理功能中可能具有重要作用 相似文献
93.
Claire Cameron 《Early child development and care》1997,137(1):47-67
A review of the international literature on staffing in childcare centres in five English language countries and Denmark reveals both remarkable similarities and interesting differences in the childcare workforce. The paper compares characteristics of the workforce; their training and professional membership. It also compares conditions of work in each country, including salaries, staff benefits, and features of the working environment such as job satisfaction and staff turnover. Findings indicate that childcare workers tend to be young and female; that a relatively high proportion of untrained staff work in childcare centres; that, except in Denmark, the level of extrinsic benefits is startlingly low. Workers are paid relatively little compared to the average pay for women in their countries but the workforce does not benefit from enhanced conditions of work to compensate for low pay. However, the level of intrinsic satisfaction with the work is high. Caring for children is a satisfying form of employment, even if it offers a limited career structure. 相似文献
94.
Complete cross-sections from the femoral midshaft of 180 individuals of known height and weight, aged 21–97 y, from a modern Australian population were examined using automatic video image analysis to quantify total subperiosteal porosity (TSPP). More specifically, the aim was to investigate whether age changes were similar in both sexes in (1) total subperiosteal area (TSPA), cortical area (CA) and medullary area (MA), (2) intracortical porosity (ICP), and (3) the respective contributions to TSPP made by MA and intracortical void area (ICVA). Our findings indicated that both sexes showed a significantly greater height normalised TSPA in the 70s as compared with the 20s. Males had consistently larger bones with a greater height normalised CA. In both sexes CA showed a tendency to increase till the 7th decade and then to decline, more so in females. MA approximately trebled in females and doubled in males over the age range studied. Although ICP also increased, from 4–6% in young adults to over 9% in the elderly, it showed a significant difference between the sexes only in the 3rd decade, being greater in males at this stage. By contrast, TSPP became significantly greater in females (from that recorded in the 3rd decade) by the time they reached the 50s, while in males this did not occur till the 80s. It increased from ∼25% in young adults of both sexes to ∼50% in females and ∼37% in males in their 80s. However, in the elderly there was great variability in both sexes in the appearance of bones from individuals of similar chronological age. Some bones differed little from those in younger subjects, others showed greatly increased ICP, still others displayed reduced cortical widths with low ICP. The femoral midshaft resembles other skeletal sites in that age changes in TSPP are more marked in females than males. 相似文献
95.
J. R. M. Copeland C. McWilliam M. E. Dewey D. Forshaw R. Shiwach R. T. Abed M. S. Muthu N. Wood 《International journal of geriatric psychiatry》1986,1(1):63-70
A random community sample of 1070 subjects aged over 65 was interviewed by trained non-medical interviewers using the Geriatric Mental State, community version (GMSA). A sub-sample of 126 subjects was selected so as to contain possible early cases of dementia, pseudo-dementia, and normal subjects; and re-interviewed, a mean 1 year and 23 weeks later, by a group of psychiatrists in training. The computer diagnosis AGECAT, based on GMSA applied by non-medical raters, had predicted at initial interview, nine out of twelve cases of dementia at follow-up and five out of nine borderline cases. An Organic/Depression Index may prove useful in predicting which of those cases with early organic levels will eventually develop dementia, depression or recover. 相似文献
96.
北京和重庆市育龄期妇女风疹抗体水平调查 总被引:3,自引:0,他引:3
目的了解北京和重庆市育龄期妇女风疹抗体水平,为控制先天性风疹综合征(CRS)提供科学依据。方法2006年6~8月随机抽取北京和重庆市各1个区作为调查点,对20~39岁育龄期妇女623人(北京市311人,重庆市312人)进行血清流行病学调查。结果北京和重庆市育龄期妇女风疹抗体阳性率分别为85.21%和78.53%,自然感染获得抗体阳性率分别为85.08%和77.89%;风疹抗体分布与年龄、地区有关,随着年龄的增长抗体阳性率和几何平均浓度有下降的趋势。结论制定科学的风疹疫苗使用策略和免疫程序,提高育龄期妇女的免疫力,是减少CRS发病的有效手段。 相似文献
97.
年龄因素对健康人心率变异性的影响 总被引:1,自引:0,他引:1
目的探讨年龄因素对健康人心率变异性(HRV)的影响。材料与方法将236例健康人分为五个年龄组,使用美国先进医用设备公司5.0版本HRV软件做短时时域及频域HRV分析。结果年龄因素对健康人HRV短时时域和频域分析的多项指标产生显著影响,随着年龄增大,时域指标中的HRSD、SDANN、rMSSD及PNN50均逐渐降低;随着年龄增长,频域指标中各频段下的绝对面积,即:VLF、LF、MF及HF均逐渐降低;而频域指标中各频段下的相对面积,即:VLFP、LFP、MFP、HFP随着年龄增长呈不同的发展趋势。LF/HF随着年龄的增加而逐渐升高。结论HRV随着年龄的增加而下降,尤以迷走神经活性下降为显著。频域指标中各频段的相对面积较绝对面积能更敏感地反映交感、迷走神经张力的消长。 相似文献
98.
男性胆囊结石患者血清性激素和前列腺素改变的探讨 总被引:1,自引:0,他引:1
借助RIA,对28例胆囊结石男性(平均57.5岁)及26名健康中、老年男性(平均63.3岁)进行了血清雌二醇(E_2)、孕酮、睾酮和前列腺素类(PGs)检测,以探索胆石形成机理。结果,1)在胆石男病人中.平均E_2和平均孕酮水平均高,他们的平均睾酮则低下,与健康对照男性相应诸值比较,差异非常显著或显著(P<0.001,0.05,0.05);2)至于平均PGs,胆石男性组者与健康对照男性相比,前者也相当高(23.01pg/ml对16.31pg/ml),只是两组间差异尚无统计学意义。作者等初步设想,胆石男性小,如同胆石女性那般,本症也可能是某种垂体性腺激素分泌紊乱性疾病。 相似文献
99.
J. H. Lin A. N. Chremos K. C. Yeh J. Antonello G. A. Hessey II 《European journal of clinical pharmacology》1988,34(1):41-46
Summary The plasma and urine concentrations of famotidine, a new, potent H2-receptor antagonist, have been measured in 16 healthy young adults, 8 healthy elderly people and 18 patients with varying degrees of renal dysfunction after intravenous administration.Both the plasma elimination and renal excretion of famotidine were decreased in the elderly volunteers and renal patients. The renal clearance of famotidine averaged 4.43 ml/min/kg (310 ml/min) in normal young volunteers, which exceeded the mean creatinine clearance 1.55 ml/min/kg (109 ml/min), suggesting net secretion is a significant mechanism for elimination of famotidine.The ratio of famotidine renal clearance to creatinine clearance decreased as creatinine clearance decreased; these results suggest that the deterioration in the secretion process was much faster than that in glomerular filtration and are incompatible with the intact nephron hypothesis. Nevertheless, both total body clearance and renal clearance were significantly correlated with creatinine clearance.The apparent half-life was also significantly correlated with creatinine clearance. Since famotidine is essentially free of dose-related adverse effects, dose adjustment in patients with mild renal insufficiency and in elderly people is not required; however, either a prolonged dosing interval or a decrease in daily dose during long-term therapy may be adapted for the patients with severe renal insufficiency to avoid accumulation and the potential undesirable effects. 相似文献
100.
Marcia S. Driscoll Thomas M. Ludden Daniel T. Casto Louis C. Littlefield 《Journal of pharmacokinetics and pharmacodynamics》1989,17(2):141-168
Routine clinical pharmacokinetic data collected prospectively from pediatric patients receiving theophylline were analyzed using the NONMEM (nonlinear mixed effects model) digital computer program. A total of 314 measured serum theophylline concentrations (STCs) were obtained from 84 hospitalized patients ranging in age from 4 months to 15.2 years with the majority of patients between the ages of 1 and 8 years. Fifty-six percent were male. The race/ethnicity distribution was 71.4% Latin, 15.5% black, 11.9% Caucasian, and 1.2% (one subject) Pakistani. Of the total number of observed STCs, 16.2% reflected some degree of outpatient dosing. The pharmacokinetic model used was a one-compartment open model with either zero-order or first-order absorption and first-order elimination. Age was the most important determinant of theophylline clearance (Cl);weight was inferior to age and did not statistically improve the model (p>0.005when combined with age. Total Clincreased by 10%/year over the age range of 1 to 15 years of age. Black race and male gender were associated with higher Clvalues: for a given age, Clwas 34% higher for blacks than the reference population composed of the remaining patients, and Clfor males was 25% higher than that for females. The volume of distribution (Vdfor the population was estimated to be 0.62 L/kg. The interindividual variability in Cland Vdexpressed as coefficients of variation were 19 and 28%, respectively. The residual intraindividual error variance corresponded to a standard deviation of 2.8 g/ml. The STCs that represented some degree of outpatient dosing were 21 % lower than those reflecting only inpatient dosing. Alternate models that include weight as a determinant of theophylline clearance are also provided. The NONMEM method of determining population pharmacokinetics is well suited to the pediatric population since it does not require a large number of STCs per patient. In this study a mean of only 3.7 STCs per patient were utilized to provide information which should prove useful in the design and adjustment of theophylline dosage regimens in children. 相似文献