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51.
52.
Abstract –This study investigated whether two new composite dental indicators -"the number of functioning teeth" and "the number of sound-equivalent teeth" are more efficient than the conventional DM FT index in revealing the social and behavioural factors which are significantly related to oral health status. The arbitrary set of weights given to the T-Health indicator was also evaluated. The number of functioning teeth was defined as the aggregate of filled (otherwise sound) and sound teeth. The T-Health was defined as a weighted average of sound teeth, filled (otherwise sound) teeth and teeth with some decay, the weights intended in principle to represent the relative amounts of sound tissue in these three categories of teeth. An arbitrary set of weights was used: 4, 2, and 1 for sound, filled, and decayed teeth, respectively. 164 families (father, mother and at least one 13-yr-old child) from Belo Horizonte, Brazil, were randomly selected from 13-yr-old children from private and state schools. The parents'ages ranged from 35 to 44 yr. Socio-economic status, area of residence, level of education, family income, sugar consumption, toothbrushing frequency and type of dental attendance were the social and behavioural oral health risk-factors considered in this study. The results indicated that the two new dental indicators are more sensitive to the influence of social and behavioural factors, such as those investigated here, than is the traditional DM FT index. A different set of weights (4, I, and I for sound, filled, and decayed) was suggested for the construction of the T-Health.  相似文献   
53.
In much of the literature to date, the definition of climacteric symptoms has been based largely upon women who present for medical treatment of symptoms. It is already well recognised that patients (of all ages and both sexes) presenting for medical treatment tend to report themselves as suffering from more life stresses and from more neurotic symptoms than people in the general population. Life stress and adequacy of coping may thus be important factors in the incidence of symptomatology at the climacteric, as at any other time of life. This study therefore investigated the proposal that post-menopausal women who present for treatment at menopause clinics suffer from more life stresses and more neurotic symptoms than post-menopausal women in the general pupolation.

It was found that patients did indeed suffer from more psychosocial stress, measured in terms of life events, clinical depression and anxiety scales and a rating scale based on a clinician's judgements of ongoing psychosocial stress, vulnerability and adequacy of coping. Patients also suffered from significantly more symptoms than non-patients, not only psychological, but also hypothalamic and metabolic symptoms. However, the incidence of hot flushes and vaginal atrophy was the same in both groups. The stress/coping rating was the measure which correlated most highly with the psychological symptoms reported by subjects as symptoms of menopause. Life events and clinical stress measures were more consistently related in the non-patient group, indicating possible intervening variables (such as hormone imbalance) in this relationship in the patient group.  相似文献   

54.
The effect of saline adaptation on the intracellular Na, K, Cl, P concentrations and dry weight content of the toad skin epithelium (Bufo viridis) was studied using the technique of electron microprobe analysis. The measurements were performed on isolated abdominal skins either directly after dissection or after additional incubation in Ussing-type chambers.Adaptations of the toads to increasing NaCl concentrations for 7 days resulted in increased blood plasma osmolarity and a parallel increase in the cellular electrolyte, P and dry weight concentrations of the epithelium, the K increase representing the most significant fraction of the intracellular osmolarity increase. No evidence was obtained to show that the nucleus and cytoplasm reacted differently from each other and all living epithelial cell types basically showed the same response.Incubation of the isolated skins under control conditions showed a drastic inhibition of the transepithelial Na transport after adaptation to high salinities. In spite of the large variations in the transport rate almost identical intracellular electrolyte concentrations were observed. In tap water adapted toads the average cellular concentrations were 8.8 mmole/kg wet weight for Na, 109.6 for K, 41.5 for Cl, and 135.3 for P, respectively. Incubation of the skin with Ringer's solution of different osmolarities demonstrated that the epithelial cells are in osmotic equilibrium with the inner bathing solution. The results are consistent with the view that the osmotic adaptation is mainly accomplished by the movement of water.This work was supported by grants from the Deutsche Forschungsgemeinschaft and the Stiftung Volkswagenwerk  相似文献   
55.
骨骼肌介电行为的理论模型仿真   总被引:1,自引:1,他引:1  
在 10 0 Hz~ 10 0 MHz范围内 ,应用椭圆壳介电理论模型 ,经过模拟仿真蛙骨骼肌细胞的介电行为 ,确定了蛙骨骼肌细胞的椭圆壳模型各相参数。为将来对骨骼肌疲劳、肌营养不良和肌肉萎缩等病症的模型分析奠定理论基础。  相似文献   
56.
The cognitive behaviour therapy (CBT) emphasis on treatment relevance in assessment, and on evidence‐based intervention, has led to an increasing focus on problem maintenance factors (vs. precipitants) in both its models of psychopathology and in its individual case formulations. This article describes the reasons for this growing focus, and presents a generic CBT model based on the functional analysis of “problem‐maintaining circles” (PMCs) of causes. Some samples of the profuse literature implicating PMCs in many psychological disorders are presented, and the utility of PMC‐based functional analysis, case formulation, or modelling of psychopathology is advanced, not only as a guide to selection of therapeutic interventions, but as an alternative to standard psychiatric diagnosis. A sampling of a taxonomy of such PMCs is presented. And finally, the clinical application of PMC‐based functional analysis, case formulation, and treatment selection is illustrated in five case illustrations drawn from a recent clinical caseload.  相似文献   
57.
Sildenafil is a specific inhibitor of phosphodiesterase (PDE) type 5 and represents a powerful therapy for male erectile dysfunction (ED) of different aetiology. Recently, sildenafil has been shown to restore erections in temporary ED related to the need of semen collection for assisted reproductive techniques. In this study, we investigated whether sildenafil administration modifies seminal parameters and/or erectile function in normal healthy volunteers. In a double-blind, randomized, placebo-controlled, cross-over two period investigation we enrolled 20 healthy male volunteers (mean +/- SE age 32 +/- 0.5 years). Subjects were not using any medication for the 3 month period prior to the study and were engaged in a stable relationship with proven fertility. The effects of sildenafil (100 mg) on seminal parameters and erectile function after audiovisual sexual stimulation were evaluated by semen analysis and by colour-Duplex ultrasound (the Resistive Index) respectively. In all subjects, sildenafil caused no changes in seminal and erection parameters when compared to placebo. Interestingly, sildenafil administration led to a marked reduction of the post-ejaculatory refractory time (10.8 +/- 0.9 min versus 2.6 +/- 0.7 min for placebo and sildenafil respectively; P < 0.0001). These results indicate that in normal subjects acute sildenafil treatment does not modify semen characteristics and has a positive influence over the resumption of erections following ejaculation in the presence of a continuous erotic stimulus.  相似文献   
58.
As an evolvement of Pavlov ideas on higher nervous (psychic) activity 'the need-informational theory of emotions' was suggested by the author in 1964. According to it an emotion is a function of two major factors: (1) power and quality of actual need (or drive, or motivation) and (2) estimation of probability (possibility) of need satisfaction on the basis of phylo- and ontogenetic experience. In the process of experimental testing of 'the need-informational theory of emotions' the role of different cerebral structures (frontal neocortex, hippocampus, amygdala, hypothalamus) in the genesis of emotional states and in the organization of goal-directed behavior was elucidated. The experimental data showed that these 4 brain structures play the major role in estimation of signals coming from environment and in the choice of subject's reactions. The individual characteristics of the interaction between the 4 brain structures must be taken into consideration in discussing neurophysiological backgrounds of different types of the higher nervous activity (temperaments), parameters of extra-introversion and neurotism (emotionality), the formation of main types of neurosis.  相似文献   
59.
This study examined the effects of certain characteristics of human immunodeficiency virus (HIV)-infected patients related to the risks of practising unprotected sex (UPS) among 919 HIV-infected patients who attended the sexually transmitted disease (STD) clinic of the Taipei City STD Control Center, Taiwan, during the period January–July 2004. After learning that they were HIV-positive, 517 (56%) subjects had practised UPS, 476 (52%) had a new STD diagnosis, and 106 (12%) had used some form of injected drug. UPS was reported by 76% of homosexual/bisexual males, 19% of heterosexual males and 5% of females, and was reported more often by those individuals with casual sexual partners (p < 0.001). According to multivariate logistic regression analyses, UPS was associated with male-tomale sexual intercourse (OR 2.46; 95% CI 1.26–4.86, p < 0.001), with casual sexual partners (OR 2.82; 95% CI 1.62–4.88, p < 0.001), and with an individual's knowledge of his/her HIV status for > 11 years (OR 2.06; 95% CI 1.02–4.18, p < 0.05). Although using anti-retroviral therapy to prevent sexual transmission of HIV is rational, the avoidance of at-risk sexual behaviour should also be a priority among HIV-seropositive individuals. Ongoing risk-reduction counselling related to HIV transmission is needed to reduce certain sexual behaviours associated with HIV transmission.  相似文献   
60.
Structure and properties of methacrylate based dental restorative materials   总被引:1,自引:0,他引:1  
The chemistry and structure of the dimethacrylate resins and the nature of the filler systems in dental composite resins are reviewed in relation to their influence on the setting behaviour, dimensional stability, aesthetics, fracture behaviour and adhesive potential. It is clear that a deeper understanding of the structure of the polymeric matrix and the mechanism of clinical wear is required. As a result of ongoing research in this area and with the development of dentine adhesives, the future prospects of composite resins are encouraging.  相似文献   
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