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61.
Summary Early recognition of recurrence and work-up of clinically indeterminate lesions may be impaired after reconstruction with silicone implants due to superimposition of the implant or to scarring. This study was undertaken to evaluate the use of contrast-enhanced MRI in patients with silicone implant after breast cancer. Contrast-enhanded MRI was offered to 169 patients. Comparative two- to three-view mammography was also performed in 169 patients, as well as comparative sonography in 144 patients. Conventional imaging and clinical examination detected only 8/13 recurrences, whereas 12/13 were detected by MRI. One recurrence had been visible as a strongly enhancing 2-mm dot in a previous examination (2 years before), but was not called. It was therefore counted as false negative. In addition, multicentricity was detected by MRI alone in two of three cases. MRI correctly diagnosed scar tissue in all cases with indeterminate findings. However, due to false-positive calls caused by enhancing granulomas specificity could not be improved. Contrast-enhanded MRI allowed decisive additional information in our study group and improved the sensitivity significantly (concerning all diagnoses). Contrast-enhanded MRI is recommended in patients with diagnostic problems or high risk of recurrence after silicone implants.   相似文献   
62.
Newer policies of community care for those with disabilities have resulted in the home becoming the usual site of care. Policy makers must now give attention to the needs of those at home giving this care. This article explores the constraints on sociability opportunities of 73 mothers who were caring for children with disabilities. These opportunities are often built into leisure pursuits for women without caring responsibilities. However, choice of out-of-house leisure activity was circumscribed for the mothers in this study and their reported leisure activities revolved around home and neighbourhood. Even these sites offered limited scope for sociability because of the way in which caring affected domestic space and because of the characteristics of the modern Australian suburb. It is argued in this paper that personal time and personal domestic space are needed by care-givers so their sociability needs can be fulfilled. An understanding of the constraints imposed by use of the home as a place of care may make possible the planning of a rearrangement of domestic space to increase sociability opportunities for carers.  相似文献   
63.
Summary Cytochemical staining of normal human bone cells in monolayer cultures for alkaline phosphatase (ALP) indicated that the cultures contained mixed-cell populations. Time course evaluations of the cytochemical staining revealed, in addition to the ALP-negative cell population, at least two subpopulations of ALP-positive human bone cells with different levels of ALP. A cytochemical method has been developed which separates the ALP-positive cells into high and intermediate ALP subpopulations. In this method, human bone cells were stained for ALP using an azo-dye method and incubating at 4°C for 10 and 30 minutes, respectively. We defined the cell population that stained positively for ALP at 10 minutes as strong ALP-positive cells, and both strong and intermediate cells were stained at 30 minutes. The intermediate cells were determined from the difference between the values at the two time points. The intra- and interassay variations of the assay, with the same investigator in blinded investigations, were both less than 10% and the interobserver variation was approximately 25%. Analysis of the distribution of ALP levels in cells with a laser densitometer confirmed the presence of at least three cell subpopulations. 1,25(OH)2D3 treatment increased the proportions of both ALP-positive cell populations, whereas TGF-beta treatment increased only the intermediate ALP-positive cell population. On the contrary, fluoride increased the proportion of the strong ALP cells, and IGF-1 had no effect on the proportions of either ALP-positive subpopulation. When the ALP-specific activity was compared with the percentage of each ALP-positive subpopulations for the cells treated with effectors, the ALP-specific activity correlated with the total ALP-positive and with the strong ALP-positive populations but not with the intermediate ALP-positive subpopulation. In summary, this study represents the first evidence that normal human bone cells in monolayer cultures contained at least two subpopulations of ALP-positive cells, and that bone cell effectors could have differential effects on each cell population.  相似文献   
64.
心理因素对小学生脑力工作能力影响的研究   总被引:4,自引:2,他引:2  
采用横断面研究方法,对180名小学三年级学生脑力工作能力与其智力、性格、学习动机等心理因素和学习、睡眠时间等作息因素的关系进行分析研究。验证了学习、睡眠时间是影响学生脑力工作能力重要的外部因素;脑力工作能力与智力和学习成绩呈正相关。学生自身的心理因素中,学习动机对脑力工作能力有重要影响,所以激发和强化学生的学习动机,是保持和提高学生学习工作能力的有效手段;而性格内外向性、情绪稳定性等因素,对脑力工作能力的影响不明显。  相似文献   
65.
What is the value of bcl-2 protein detection for histopathologists?   总被引:15,自引:0,他引:15  
  相似文献   
66.
The present study was undertaken to evaluate the role and possible interaction of the endogenous opioid peptide (EOP) and corticotropin-releasing factor (CRF) in the acute stress-induced suppression of gonadotropin secretion in ovariectomized estrogen-primed rats. An intravenous (i.v.) injection of naloxone (10 or 20  mg/kg), an EOP antagonist, significantly elevated serum luteinizing hormone (LH) levels within 10  min in non-stressed animals. The naloxone-induced LH release was completely eliminated when tested 30  min after the onset of acute immobilization. In a subsequent study, it was found that suppression of the naloxone-induced LH release occurred as early as 5  min after the stress onset, and was still evident 60  min after the end of a 30-min period of immobilization. The effect of naloxone was restored 3  h after liberation of the animal from the 30-min immobilization. An intraventricular (i.c.v.) injection of CRF (1 or 5  μg) also significantly suppressed, in a dose-related manner, the effect of a subsequent i.v. injection of naloxone. However, an i.c.v. injection of α -helical CRF(9-41) (25 or 50  μg), a CRF antagonist, prior to immobilization, could not interfere with the suppressive effect of stress on naloxone-induced LH release. These results suggest that both acute immobilization stress and CRF can inhibit the LH secretory activity without mediation by EOP neurons. However, the stress-related suppression may involve non-CRF mechanism(s).  相似文献   
67.
为提供微波辐射安全标准必要的数据,研究了不同极化方向微波辐射能量对猕猴的影响。实验在医学微波无反射室中进行,分为电场,磁场和微波传输方向极化组,辐射频率1GHz,用红外热图技术,对暴露在三种极化方向电磁场中猕猴面部各解剖特片部位及胸部在辐射前后进行温度变化的定量分析。  相似文献   
68.
Using hierarchical cluster analysis, applied to 47 cases of Guillain-Barre Syndrome (GBS) incident in South-West Stockholm (SWS) during the period from January 1973 to June 1992, we identified three major clinicoepidemiological subgroups. The first subgroup, 25.5% of the cases (26.7 ± 6.7 years), recorded a peak incidence at ages 20–29 years and presented significant differences from other subgroups, a high proportion of cases with onset at low age preceded by respiratory infection (83.3%) and with normal motor conduction velocity (50.0%). Also found, were less affected biological parameters, a rapidly progressive course and independence in gait at one month after onset. A second subgroup, 27.7% of cases, was severely affected, clinically and functionally. It consisted predominantly of young individuals (22.7 ± 11.1 years), with a high incidence (69.2% of cases) in autumn. A third subgroup, comprising 40.47; of cases, was older (61.1 ± 11.0 years) and, in general, also severely affected. The incidence of this form appeared to be invariant with time.  相似文献   
69.
Summary Squamous cell carcinoma of the head and neck is a disease predominantly of males and is due to a variety of known environmental irritants, notably cigarette smoke. Dietary, viral and immunological factors may also be relevant. Head and neck squamous cancers express epidermal growth factor receptors and some show weak levels of oestrogen receptor activity, but a reliable serum marker of tumour burden remains to be identified. The prognosis is found to be less favourable in females, in those with advanced T stage, in association with multiple node involvement, especially where extracapsular spread is present and where the T4/T8 ratio is elevated. Administration of heterologous blood during therapy may also have an adverse effect on prognosis. Interested clinicians must remember that most cases are preventable. Correspondence to: A.G.D. Maran  相似文献   
70.
尼罗罗非鱼肉营养成分分析   总被引:3,自引:0,他引:3  
<正> 尼罗罗非鱼(Tilapia nilotica)是我国从非洲引进的热带鱼类,具有刺少肉味鲜嫩、食性广、生长快、繁殖力强、养殖周期短等特点。已快速地养殖到全国各地。作者对利用地热资源人工喂养条件下的尼罗罗非鱼肉的氨基酸和肉内的粗蛋白、脂肪、维生素等成分进行分析,评估尼罗罗非鱼肉的营养价值,从营养学的角度为人们提供科学依据。  相似文献   
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