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821.
Generalized anxiety disorder (GAD) is a common psychiatric disorder characterized by constant worry or anxiety over every day life activities and events. The neurobiology of the disorder is thought to involve a wide cortical and subcortical network that includes but is not limited to the amygdala and the bed nucleus of the stria terminalis (BNST). These two regions have been hypothesized to play different roles in stress and anxiety; the amygdala is thought to regulate responses to brief emotional stimuli while the BNST is thought to be involved in more chronic regulation of sustained anxiety. In this study, we exposed medication-free GAD patients as well as non-anxious controls to a gambling game where one of the conditions involved non-contingent monetary loss. This condition of high uncertainty was intended to elicit a stressful response and sustained anxiety. Functional MRI scans were collected simultaneously to investigate BOLD activity in the amygdala and BNST during performance of this task. Compared to controls, we found that GAD patients demonstrated decreased activity in the amygdala and increased activity in the BNST. Skin conductance measures showed a consistent early versus late effect within block where GAD patients demonstrated higher arousal than controls late in the task blocks. Based on these results, we hypothesize that GAD patients disengage the amygdala and its response to acute stress earlier than non-anxious controls making way for the BNST to maintain a more sustained response. Future studies are needed to investigate the temporal dynamics of activation and deactivation in these regions. 相似文献
822.
Yassa L Cibas ES Benson CB Frates MC Doubilet PM Gawande AA Moore FD Kim BW Nosé V Marqusee E Larsen PR Alexander EK 《Cancer》2007,111(6):508-516
BACKGROUND: The diagnostic evaluation of patients with thyroid nodules is imprecise. Despite the benefits of fine-needle aspiration (FNA), most patients who are referred for surgery because of abnormal cytology prove to have benign disease. Recent technologic and procedural advances suggest that this shortcoming can be mitigated, although few data confirm this benefit in unselected patients. METHODS: A total of 2587 sequential patients were evaluated by thyroid ultrasound and were offered ultrasound-guided FNA (UG-FNA) of all thyroid nodules that measured > or =1 cm during a 10-year period. Results of aspiration cytology were correlated with histologic findings. The prevalence of thyroid cancer in all patients and in those who underwent surgery was determined. Surgical risk was calculated. RESULTS: Tumors that measured > or =1 cm were present in 14% of patients: Forty-three percent of patients had tumors that measured <2 cm in greatest dimension, and 93% had American Joint Committee on Cancer stage I or II disease. The cytologic diagnoses 'positive for malignancy' and 'no malignant cells' were 97% predictive and 99.7% predictive, respectively. Repeat FNA of initial insufficient aspirates, as well as more detailed classification of inconclusive aspirates, improved preoperative assessment of cancer risk and reduced surgical intervention. Fifty-six percent of patients who were referred for surgery because of abnormal cytology had cancer compared with from 10% to 45% of patients historically. An analysis of operative complications from a subset of 296 patients demonstrated a 1% risk of permanent surgical complications. CONCLUSIONS: The current findings demonstrated the benefits of UG-FNA and of a more detailed classification of inconclusive aspirates in the preoperative risk assessment of thyroid nodules, supporting adherence to recently published guidelines. 相似文献
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824.
Rom e JALM Snijders Piotr Milkiewicz Christoph Schramm Tom JG Gevers 《World journal of hepatology》2021,13(11):1642-1652
Autoimmune hepatitis (AIH) is a severe chronic autoimmune disease and has a significant impact on the patient’s quality of life, in particular regarding psychological problems such as anxiety and depression. Consistent evidence on which patient-related, disease-related or physician-related factors cause health-related quality of life (HRQoL) impairment in patients with AIH is lacking. Current studies on HRQoL in AIH are mainly single-centered, comprising small numbers of patients, and difficult to compare because of the use of different questionnaires, patient populations, and cutoff values. Literature in the pediatric field is sparse, but suggests that children/adolescents with AIH have a lower HRQoL. Knowledge of HRQoL and cohesive factors in AIH are important to improve healthcare for AIH patients, for example by developing an AIH-specific chronic healthcare model. By recognizing the importance of quality of life beyond the concept of biochemical and histological remission, clinicians allow us to seek enhancements and possible interventions in the management of AIH, aiming at improved health. 相似文献
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