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101.
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Technical advances that enable the noninvasive measurement of biomarkers in saliva have spawned a generation of investigations that integrate biological variables into behavioral and developmental research. This study examines whether the collection of saliva, using common absorbent devices compromises the measurement of cortisol when saliva specimens have low sample volume. Within subjects (n = 20), saliva samples were prepared to experimentally represent a gradient of lower to higher sample volumes. One aliquot was immediately frozen (no treatment control) and the remaining aliquots were absorbed ("collected") using one of three collection techniques employed in studies of child development (e.g., braided cotton dental rope, Salivette cotton pledget, or hydrocellulose microsponge). The sample volume recovered from each device relative to the initial volume available to be absorbed, and cortisol level recovered from each device relative to the untreated-control condition were measured. Results reveal that for certain collection devices (1) the percent volume recovered is related to the initial volume available to be absorbed, (2) a substantial percentage of cortisol in saliva specimens can remain in absorbent material, and (3) the percent of cortisol recovered can be associated with the initial sample volume available to be absorbed. When research participants, such as young children, produce low volume saliva specimens, some absorbent devices may have the potential to introduce error variance in the measurement of salivary cortisol.  相似文献   
103.
Attention deficit hyperactivity disorder (ADHD) is a common developmental disorder. The present study tested the hypotheses that children with ADHD, particularly those exhibiting severe hyperactivity and impulsivity, have a different stress reaction (measured by salivary cortisol) during a dental recall visit and are more dentally anxious than children in a control group. Eighteen children with ADHD and a control group of 71 children, all 13 yr of age, underwent a clinical dental examination and completed the Corah Dental Anxiety Scale (CDAS). Four saliva samples were gathered for analysis of cortisol: one prior to dental examination, one after, and two the following morning. The subgroup ADHD with hyperactivity/impulsivity had statistically significantly lower cortisol levels than the control group 30 min after awakening. When cortisol values were plotted on a timeline, this subgroup always had lower cortisol concentrations than children in the control group. There was a significant correlation between CDAS scores and cortisol concentrations prior to the dental examination in both the ADHD and the control group. Behavioral expressions of anxiety in children with ADHD may be different from those in other children, not only due to the characteristics of their disorder, but also because of lower stress reactivity.  相似文献   
104.
肾上腺腺瘤是临床上较常见的一种肿瘤。目前,影像组学在肾上腺良、恶性肿瘤,功能性肾上腺腺瘤亚型以及脂质性腺瘤和嗜铬细胞瘤的鉴别中取得初步进展,主要通过纹理分析、直方图分析等影像组学特征对肾上腺腺瘤展开研究,可有效评估肿瘤的异型性,可在临床决策上提供有效的帮助。此外,临床特征与影像组学特征结合的诺模图模型对功能性肾上腺腺瘤亚型具有良好的鉴别效果。现综述影像组学在肾上腺腺瘤的诊断和鉴别诊断以及治疗策略的疗效预测、监测和预后评估的研究现状、存在问题,并对未来进行初步展望。  相似文献   
105.
目的:探讨重性抑郁障碍首次发病患者记忆损害与血清皮质醇的关系。方法:对30例重性抑郁障碍首次发病患者和30名正常对照者进行韦氏记忆量表(WMS)测量以评定其记忆水平,同时进行血清皮质醇的浓度测定。结果:重性抑郁障碍组的韦氏记忆商数及心智、图片、再认、再生、联想、理解、背数因子分显著低于正常对照组﹙P0.01﹚;韦氏记忆因子中的心智、图片、再认、再生、联想、背数、理解、记忆商数与HAMD总分以及HAMD因子中的焦虑/躯体化、认识障碍、阻滞、睡眠障碍显著负相关(P0.05);血清皮质醇浓度与韦氏记忆因子中的心智、图片、再认、再生、联想、背数、记忆商数显著负相关(r分别=-0.432,-0.410,-0.399,-0.421,-0.472,-0.436,P0.05);重性抑郁障碍患者的韦氏记忆各因子得分与其年龄、病程存在负相关(P0.05)。结论:重性抑郁障碍首次发病患者急性期存在记忆功能减退,并与血清皮质醇浓度可能存在相关性。  相似文献   
106.

Objective:

Borderline and antisocial personality disorders (PDs) share common clinical features (impulsivity, aggressiveness, substance use disorders [SUDs], and suicidal behaviours) that are greatly overrepresented in prison populations. These disorders have been associated biologically with testosterone and cortisol levels. However, the associations are ambiguous and the subject of controversy, perhaps because these heterogeneous disorders have been addressed as unitary constructs. A consideration of profiles of people, rather than of exclusive diagnoses, might yield clearer relationships.

Methods:

In our study, multiple correspondence analysis and cluster analysis were employed to identify subgroups among 545 newly convicted inmates. The groups were then compared in terms of clinical features and biological markers, including levels of cortisol, testosterone, estradiol, progesterone, and sulfoconjugated dehydroepiandrosterone (DHEA-S).

Results:

Four clusters with differing psychiatric, criminal, and biological profiles emerged. Clinically, one group had intermediate scores for each of the tested clinical features. Another group comprised people with little comorbidity. Two others displayed severe impulsivity, PD, and SUD. Biologically, cortisol levels were lowest in the last 2 groups and highest in the group with less comorbidity. In keeping with previous findings reported in the literature, testosterone was higher in a younger population with severe psychiatric symptoms. However, some apparently comparable behavioural outcomes were found to be related to distinct biological profiles. No differences were observed for estradiol, progesterone, or DHEA-S levels.

Conclusions:

The results not only confirm the importance of biological markers in the study of personality features but also demonstrate the need to consider the role of comorbidities and steroid coregulation.  相似文献   
107.
Prior research has shown that an additional training session immediately after acute stress decreases release of salivary cortisol in a college student group trained with 5‐day integrative body–mind training (IBMT) in comparison with a control group given the same amount of relaxation training. However, 5 days of training does not influence the basal secretion of cortisol. The current study seeks to extend this finding and determine whether increasing amounts of IBMT will decrease the basal cortisol level, suggesting reduced stress to daily activities. Thirty‐four Chinese undergraduates were randomly assigned either to 4 weeks of IBMT or a relaxation control. Salivary cortisol levels at baseline before training and the three stages of a stress intervention test (i.e. rest, stress and additional 20‐min practice) after 2 and 4 weeks of training were assessed. The basal cortisol level decreased significantly in the IBMT but not in relaxation group after 2 and 4 weeks of training. An additional IBMT practice session immediately after acute stress produced significantly lower cortisol release for the IBMT group in comparison with relaxation at weeks 2 and 4. The results indicate that IBMT produces a change in the basal endocrine system and larger acute effects as the dose of training increases. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
108.
109.
110.

Background

Early detection of autoimmune Addison's disease (AAD ) is important as delay in diagnosis may result in a life‐threatening adrenal crisis and death. The classical clinical picture of untreated AAD is well‐described, but methodical investigations are scarce.

Objective

Perform a retrospective audit of patient records with the aim of identifying biochemical markers for early diagnosis of AAD .

Material and Methods

A multicentre retrospective study including 272 patients diagnosed with AAD at hospitals in Norway and Sweden during 1978–2016. Scrutiny of medical records provided patient data and laboratory values.

Results

Low sodium occurred in 207 of 247 (84%), but only one‐third had elevated potassium. Other common nonendocrine tests were largely normal. TSH was elevated in 79 of 153 patients, and hypoglycaemia was found in 10%. Thirty‐three per cent were diagnosed subsequent to adrenal crisis, in whom electrolyte disturbances were significantly more pronounced (P < 0.001). Serum cortisol was consistently decreased (median 62 nmol L?1 [1–668]) and significantly lower in individuals with adrenal crisis (38 nmol L?1 [2–442]) than in those without (81 nmol L?1 [1–668], P < 0.001).

Conclusion

The most consistent biochemical finding of untreated AAD was low sodium independent of the degree of glucocorticoid deficiency. Half of the patients had elevated TSH levels. Only a minority presented with marked hyperkalaemia or other nonhormonal abnormalities. Thus, unexplained low sodium and/or elevated TSH should prompt consideration of an undiagnosed AAD , and on clinical suspicion bring about assay of cortisol and ACTH . Presence of 21‐hydroxylase autoantibodies confirms autoimmune aetiology. Anticipating additional abnormalities in routine blood tests may delay diagnosis.
  相似文献   
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