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101.
102.
Cryosurgery with liquid nitrogen is one of the most used treatments for actinic keratosis. We aimed to study the effectiveness of two consecutive sessions of cryosurgery for actinic keratosis and investigate factors associated with its therapeutic success. Hence, we conducted a longitudinal study including 92 patients of both sexes, aged 50–75 years with 5–50 actinic keratosis on the face and forearms, who underwent cryosurgery and treatment with sunscreen SPF 30, at baseline and after 120 days. The lesions were counted in duplicate by the same examiner before the start of treatment and after 120 (N = 92) and 300 days (N = 33), represented by their medians and quartiles and compared using the generalized linear mixed effects model (negative binomial). Treatment behavior was investigated in relation to sex, age, education, skin type, smoking, sun exposure at work and the use of aspirin, anti-inflammatory and angiotensin-converting enzyme inhibitors. There was a significant reduction in the actinic keratosis count on the face and forearms (p < 0.05). Our results confirmed the effectiveness of cryosurgery for actinic keratosis, with a 57% reduction in the number, and size of the lesions. Higher education levels (p = 0.02) and less sun exposure at work (p = 0.02) independently promoted a significant reduction in the actinic keratosis count. Different population groups showed characteristic responses to the treatment, which may be explained by the degree of adherence to the use of photoprotection. In two sessions, cryosurgery with liquid nitrogen reduced the actinic keratosis count.  相似文献   
103.
Testosterone is an important regulator of social–motivational behavior and is known for its dominance-enhancing and social-anxiolytic properties. However, to date no studies have systematically investigated the causal effect of testosterone on actual social approach–avoidance behavior in humans. The present study sets out to test the effects of testosterone administration in healthy female volunteers using an objective implicit measure of social motivational behavior: the social Approach–Avoidance Task, a reaction time task requiring participants to approach or avoid visually presented emotional (happy, angry, and neutral) faces. Participants showed significantly diminished avoidance tendencies to angry faces after testosterone administration. Testosterone did not affect approach–avoidance tendencies to social affiliation (happy) faces. Thus, a single dose testosterone administration reduces automatic avoidance of social threat and promotes relative increase of threat approach tendencies in healthy females. These findings further the understanding of the neuroendocrine regulation of social motivational behavior and may have direct treatment implications for social anxiety, characterized by persistent social avoidance.  相似文献   
104.
The neuropeptide oxytocin regulates a wide variety of social behaviors across diverse species. However, the types of behaviors that are influenced by this hormone are constrained by the species in question and the social organization that a particular species exhibits. Therefore, the present experiments investigated behaviors regulated by oxytocin in a eusocial mammalian species by using the naked mole-rat (Heterocephalus glaber). In Experiment 1, adult non-breeding mole-rats were given intraperitoneal injections of either oxytocin (1 mg/kg or 10 mg/kg) or saline on alternate days. Animals were then returned to their colony and behavior was recorded for minutes 15–30 post-injection. Both doses of oxytocin increased huddling behavior during this time period. In Experiment 2, animals received intraperitoneal injections of either oxytocin (1 mg/kg), an oxytocin-receptor antagonist (0.1 mg/kg), a cocktail of oxytocin and the antagonist, or saline across 4 testing days in a counterbalanced design. Animals were placed in either a 2-chamber arena with a familiar conspecific or in a small chamber with 1 week old pups from their home colony and behaviors were recorded for minutes 15–30 post-injection. Oxytocin increased investigation of, and time spent in close proximity to, a familiar conspecific; these effects were blocked by the oxytocin antagonist. No effects were seen on pup-directed behavior. These data suggest that oxytocin is capable of modulating affiliative-like behavior in this eusocial species.  相似文献   
105.
Anabolic androgenic steroids (AAS) are taken by both sexes to enhance athletic performance and body image, nearly always in conjunction with an exercise regime. Although taken to improve physical attributes, chronic AAS use can promote negative behavior, including anxiety. Few studies have directly compared the impact of AAS use in males versus females or assessed the interaction of exercise and AAS. We show that AAS increase anxiety-like behaviors in female but not male mice and that voluntary exercise accentuates these sex-specific differences. We also show that levels of the anxiogenic peptide corticotrophin releasing factor (CRF) are significantly greater in males, but that AAS selectively increase CRF levels in females, thus abrogating this sex-specific difference. Exercise did not ameliorate AAS-induced anxiety or alter CRF levels in females. Exercise was anxiolytic in males, but this behavioral outcome did not correlate with CRF levels. Brain-derived neurotrophic factor (BDNF) has also been implicated in the expression of anxiety. As with CRF, levels of hippocampal BDNF mRNA were significantly greater in males than females. AAS and exercise were without effect on BDNF mRNA in females. In males, anxiolytic effects of exercise correlated with increased BDNF mRNA, however AAS-induced changes in BDNF mRNA and anxiety did not. In sum, we find that AAS elicit sex-specific differences in anxiety and that voluntary exercise accentuates these differences. In addition, our data suggest that these behavioral outcomes may reflect convergent actions of AAS and exercise on a sexually differentiated CRF signaling system within the extended amygdala.  相似文献   
106.
术语是科学概念的约定性语言符号,是科技信息交流的工具。中国的灵长类学研究虽然起步较晚,但发展迅速。在研究过程中,学者们广泛参阅、借鉴国际同行的研究成果,并引入了一些灵长类学专业术语。科学、规范、准确、明晰的表达理应成为学者们的共识,而这对信息的沟通与交流至关重要。本文阐述了科学研究术语规范化表述的重要性,并基于文献梳理,介绍了非人灵长类社会中α-雄性更替(α-male replacement)的主要类型之术语及其含义,建议国内研究者使用:(1)取代(Takeover);(2)等级反转(Rank reversal);(3)继承(Succession);(4)补缺(Waltz-in);(5)分群(Fission)。文中还讨论了影响α-雄性更替的主要因素。  相似文献   
107.
摘要 目的:探讨布南色林联合团体心理治疗慢性精神分裂症(SZ)的疗效,分析其对认知功能、社会功能和服药依从性的影响。方法:选取124例慢性SZ患者随机分为对照组和观察组,对照组口服布南色林治疗,观察组在对照组基础上加以团体心理治疗,疗程均为2个月。治疗后,采用阳性与阴性症状量表(PANSS)和临床疗效总评量表-疾病严重程度(CGI-SI)评估两组患者治疗后的疗效,采用威斯康星卡片分类测验(WCST)评估两组患者治疗前后的认知功能,采用个人和社会功能量表(PSP)评估两组患者治疗前后的社会功能,评定两组患者治疗后的服药依从性。结果:治疗后,两组患者PANSS阳性症状、阴性症状、一般精神病理评分以及总评分均低于治疗前,且观察组低于对照组(P<0.05);两组患者CGI-SI评分均低于治疗前,且观察组低于对照组(P<0.05);两组患者WCST总应答数评分均高于治疗前,且观察组高于对照组(P<0.05);两组患者PSP总评分均高于治疗前,且观察组高于对照组(P<0.05);观察组服药依从性优于对照组(P<0.05)。结论:布南色林联合团体心理治疗较单一布南色林治疗慢性SZ的治疗效果更好,能更好地提高患者的认知功能、社会功能以及服药依从性,值得临床借鉴推广。  相似文献   
108.
During the course of a study of social relationships in wild, white-faced capuchins at Lomas Barbudal, Costa Rice (May 1990–May 1993), the alpha male was deposed by a subordinate male. The rank reversal was preceded by a decline in proximity maintenance by females to the alpha male, and an increase, in the amount of aggression directed toward the alpha male by the beta female and her female coalition partners. At the time of the rank reversal, females switched from giving thegargle vocalization exclusively to the old alpha male to gargling to the new alpha male; however, juveniles were less consistent with regard to which male they gargled to. At the time of the rank reversal, most adult females reduced the time spent in proximity and grooming with the old alpha male, and increased the time spent in proximity and grooming with the new alpha male. In contrast, juveniles' patterns of affiliation with males did not change in a predictable way following the reversal. The social strategies employed by capuchin monkeys during this rank reversal are compared with those of chimpanzees.  相似文献   
109.
Social isolation usually affects the physical and mental health of the human and produces depression, whether it may relate with circadian rhythm still remains to be investigated. Two groups of mice were employed to this experiment to continuously monitoring their activities in a dark environment. Immunofluorescence was used to show the expression of the circadian clock gene in two groups of mice. The results demonstrate that the social isolation leads to decrease of mouse activities, phase advance of rhythm relatively and down-regulated of clock gene expression. We conclude that social isolation can affect the physiological function and the normal physiological rhythm of mice, which may be related to depression.  相似文献   
110.

Introduction

This study presents an analysis on the effects of positive social relationships as determining factors on the health status of the elderly, from an interdisciplinary point of view.

Materials and methods

A survey was carried out on a total of 2,332 subjects in the province of Toledo, Spain, using several scales related to the study objectives. For the multivariable analysis of the data, the linear regression, along with goodness of fit, as well as the tests of Cox, Snell and R-squared of Nagelkerke, were calculated to determine the correlation between the networks and the social contacts with the health.

Results

Good social relationships result in better health, because they allow us to feel good and add life to the years. The size of the social network, and the frequency of contacts, although decreasing with age, become vitally important at this stage of life. All these factors constitute stimuli to improve the perception of health, to provide social support in activities of daily living, as well as for instrumental or disease management.

Conclusions

The main outcome of this study is that positive social relationships can be considered as a determining factor in the health of the elderly, but not all these interactions influence the same extent. The factor of the human relationship in terms of emotional proximity, together with the frequency or quantity of these encounters, are also correlated with health, due to the emotional impact they imply.  相似文献   
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