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81.
Changes in sensory-cognitive input: effects on cerebral blood flow   总被引:1,自引:0,他引:1  
Eight healthy right-handed young men were subjected to local CBF measurement by [15O]water and positron emission tomography during partial sensory deprivation and during sensory-cognitive activation; physiological, hormonal, and subjective stress measurements were also performed. Results indicated that (a) "whole-brain" CBF increased during activation; (b) the greatest increase in CBF was in the primary visual cortex; (c) differences between hemispheres were not observed, but CBF was greater anteriorly than posteriorly in the deprivation condition only; (d) within-subject variability of CBF was not influenced by the sensory-cognitive condition; and (e) the procedure was not stressful.  相似文献   
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New community-based preventive initiatives are required if a reduction in deliberate self-poisoning is to be achieved. Local epidemiological data can be used in a health education approach, directed at professionals who have the most contact with potential cases of deliberate self-poisoning and also to those people falling within identified high-risk groups. Such initiatives require defined outcome measures and a number are proposed. The implications for data collection on deliberate self-poisoning are discussed.  相似文献   
86.
癌基因c-erbB-2在膀胱移行细胞癌中的扩增   总被引:2,自引:1,他引:1  
赵致广  张莉莉 《医学争鸣》2000,21(4):482-482
0 引言 为探讨癌基因 c- erb B- 2的扩增与膀胱移行细胞癌(TCC)的关系 ,我们以斑点杂交的方法对 40例膀胱 TCC标本中 c- erb B- 2的扩增情况进行了检测 ,以期明确 c- erb B- 2扩增与膀胱 TCC病理分级及患者预后的关系 .1 材料和方法  40例膀胱 TCC患者术后石蜡包埋标本 ,随访 5~ 10 a. 11例正常膀胱粘膜石蜡标本作为对照 . c- erb B-c DNA p CER2 0 4质粒由东京大学提供 ,Bothringer缺口平移 DNA标记试剂盒及 32 P标记 d CTP购于北京福瑞公司 .所有石蜡标本经脱蜡及蛋白酶消化 ,以酚 /氯仿抽提 DNA,乙醇沉淀 .每份样品取…  相似文献   
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Twenty-nine patients who eventually had a diagnosis of reflex sympathetic dystrophy (RSD) following total knee replacement were treated with lumbar sympathetic blocks with local anesthetic. The diagnosis was made based on the complaint of constant pain unrelated to physical activity in the absence of overt sepsis or implant loosening. In six of these cases, other factors may have clouded the diagnosis. Thirteen (44.8%) patients obtained complete relief following an average of 1.8 blocks. Three of these patients had symptoms for more than two years. Twelve patients had complete or partial relief for varying periods of time, but the relief was not sustained. Three obtained no relief at all, and in one the block could not be successfully carried out. This success rate, while shedding no light on the etiology or diagnostic accuracy, has encouraged the authors to continue with this method of treatment in such cases.  相似文献   
88.
Purpose To characterize and predict cycles generating slowcleaving embryos in in vitro fertilization, 86 cycles were retrospectively divided into two groups (slow, n=41, and fast, n=45 according to whether the number of blastomeres per embryo on day 3 was or > than the mean of the distribution, respectively.Results Cycles generating slowcleaving embryos were treated with luteinizing hormonereleasing hormone agonist before ovarian stimulation for a shorter period (12.1±0.5 versus 15.6±1.1 days; P0.01) and had higher immaturity grade of oocyte-corona-cumulus complexes which resulted in embryos (1.6±0.1 vs 1.3±0.1; P0.05) when compared to cycles producing fastcleaving embryos. Both variables entered in a logistic regression model applied in order to predict the probability of a cycle generating slowcleaving embryos (goodness-of-fit chisquare=180.0, degrees of freedom (df)=80, P=0.4786. This model predicted correctly 86.7% (13 of 15) of cycles generating slowcleaving embryos and 83.3% (10 of 12) of cycles producing fastcleaving embryos when the estimated probability of a cycle producing slowcleaving embryos was 0.7 or 0.3, respectively.Conclusion Shorter treatment with hormone-releasing hormone agonist before ovarian stimulation and higher immaturity grade of oocyte-corona-cumulus complexes which result in embryos are predictive characteristics of in vitro fertilization cycles generating slow-cleaving embryos.  相似文献   
89.
OBJECTIVES: This study determined the effect of provider (nurse or teacher) and training method (workshop or self-preparation) on outcomes of a social influences smoking prevention program. METHODS: One hundred elementary schools were stratified by school risk score (high risk = high smoking rate among senior students) and assigned randomly to conditions: (1) teacher/self-preparation, (2) teacher/workshop, (3) nurse/self-preparation, (4) nurse/workshop, and (5) control. Intervention occurred in grades 6 to 8. Smoking status at the end of grade 8 was the primary endpoint variable. RESULTS: Intervention reduced grade 8 smoking rates in high-risk schools (smoking rates of 26.9% in control vs 16.0% in intervention schools) but not in low-risk schools. There were no significant differences in outcome as a function of training method and no significant differences in outcome between teacher-provided and nurse-provided interventions in high- and medium-risk schools. Although nurses achieved better outcomes than did teachers in low-risk schools, neither provider type achieved outcomes superior to the control condition in those schools. CONCLUSIONS: Workshop training did not affect outcomes. Teachers and nurses were equally effective providers. Results suggest that programming should target high-risk schools.  相似文献   
90.
Psychological influences on the perception of immune function   总被引:5,自引:0,他引:5  
BACKGROUND: Perception of deficiencies in immunity are common in a number of patient complaints. However, little is known about the way in which individuals form perceptions about the competence of their immune system. In two studies we examined the relationship between subjects' perceptions of their immune functioning, physical symptoms, mood and measures of immunity. METHODS: In Study 1, 20 healthy volunteers completed global ratings of their immune system functioning, as well as mood and symptom reports, twice a week for 5 weeks. At the same time, blood samples were taken to assess serum IgA, IgG, and IgM antibodies. In Study 2, another sample of 58 subjects completed the same measures weekly for 5 weeks and their blood was tested for concentrations of CD3, CD4, CD8, and CD16 lymphocytes. RESULTS: We found perceptions of immune functioning to be unrelated to the concentrations of serum antibodies or blood lymphocytes. Immune perceptions were strongly related to mood and in particular, feelings of fatigue and vigour. The experience of recent physical symptoms, while not as strong as mood variables, was also important in perceptions of immune functioning. CONCLUSIONS: Mood seems to be an important determinant in the perception of immune function, and complaints about immune dysfunction in clinical situation should be investigated with this possibility in mind.  相似文献   
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