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91.
Aggressive behavior linked to corticotropin-reactive autoantibodies.   总被引:3,自引:0,他引:3  
BACKGROUND: Altered stress response is characteristic for subjects with abnormal aggressive and antisocial behavior, but the underlying biological mechanisms are unclear. We hypothesized that autoantibodies (autoAbs) directed against several stress-related neurohormones may exist in aggressive subjects. METHODS: Using enzyme-linked immunosorbent assay, we studied whether autoAbs directed against corticotropin (ACTH), alpha-melanocyte-stimulating hormone (alpha-MSH), oxytocin, and vasopressin are present in serum of male subjects with conduct disorder and prisoners with history of violence. Healthy blood donors served as control subjects. RESULTS: Both conduct disorder and prisoners groups displayed strongly increased levels of ACTH-reactive immunoglobulin G (IgG) and immunoglobulin M (IgM) autoAbs compared with control subjects. Levels of oxytocin-reactive IgM autoAbs were slightly increased in both groups of aggressive subjects, whereas levels of vasopressin-reactive IgG and IgM autoAbs were lower only in conduct disorder. No differences in the levels of alpha-MSH-reactive autoAbs were found between aggressive and control subjects. CONCLUSIONS: High levels of ACTH-reactive autoAbs as well as altered levels of oxytocin- and vasopressin-reactive autoAbs found in aggressive subjects may interfere with the neuroendocrine mechanisms of stress and motivated behavior. Our data suggest a new biological mechanism of human aggressive behavior that involves autoAbs directed against several stress-related neurohormones.  相似文献   
92.
叩击式骨应力刺激仪促进闭合性胫骨干骨折愈合   总被引:3,自引:0,他引:3  
目的观察叩击式骨应力刺激仪对闭合性胫骨干骨折愈合的促进作用。方法120例闭合性胫骨干骨折患者,随机分为应力刺激仪治疗组(治疗组61例)和对照组(59例)。治疗组每天刺激仪治疗3次,每次治疗30min,每次间隔3h;对照组仅作复位和小腿管型石膏固定。记录两组患者骨折临床愈合时间、X线片上骨折线处灰度值的变化和胫骨Johner-Wruh评分。结果治疗组临床愈合时间较对照组短(55·57d±10·09dvs78·21d±13·46d,P<0·01),骨折愈合前后X线片上骨折线处灰度值变化较对照组大(1·209±0·128vs1·117±0·245,P<0·05),治疗组Johner-Wruh评分优良率96·72%。结论叩击式骨应力刺激仪可明显加快胫骨干骨折的愈合,促进骨折处局部骨的形成。  相似文献   
93.
目的探讨物理性刺激对骨膜软骨生成方面的影响,以期培养出一种与正常关节软骨更相似的软骨组织。方法从新西兰大白兔胫骨近端内侧取下骨膜,将骨膜固定在支架上,然后将细胞支架悬吊在旋转瓶内,用水流产生的剪切应力去刺激骨膜。通过宏观观察、体积大小测量、组织切片染色与细胞外基质(ECM)成分的比较及生物力学测试分析软骨体外生长的最佳环境。结果宏观观察发现软骨生长的方向与水流的方向相同。组织切片染色可见有两层不同形态的软骨细胞和不同密度的ECM,免疫组织化学染色见在剪切应力的刺激下,软骨表面可分泌浅层蛋白质及润滑剂,且在不同大小的剪切应力刺激时,软骨表面还会产生不同厚度的表层。结论剪切应力刺激能使骨膜上的干细胞分化形成软骨,同时证明力学环境不仅影响细胞的分化与生长,而且影响细胞的形态与ECM的分泌。  相似文献   
94.
目的通过探讨前循环缺血性卒中老年患者颈总动脉分叉处血流壁切应力的水平分析其在颈动脉斑块形成过程中的影响。方法本研究选择前循环缺血性卒中老年患者,应用经皮血管彩超测量颈动脉斑块及其稳定性以及对研究对象测量患侧颈动脉血流速度、血管内径和血液粘滞度,通过公式计算血流壁切应力。结果无斑块组和有斑块组之间、高回声和低回声斑块组之间血流壁切应力均有显著性差异(P<0.01)。结论血流壁低切应力促进颈动脉斑块、尤其是不稳定斑块的形成。  相似文献   
95.
Future perspectives and research initiatives in fast-track surgery   总被引:10,自引:0,他引:10  
Background and aims Major surgery is still followed by a risk of morbidity, a need for hospitalisation and convalescence. Fast-track surgery has been introduced as a coordinated effort to combine unimodal evidence-based principles of care into a multi-modal effort to enhance recovery. The aim of this article was to update recent data on fast-track abdominal surgery and outline future strategies for research.Results The data from fast-track colonic resection support the validity of the concept because pain, ileus, cardiopulmonary function and muscle function were all improved, compared with traditional treatment and with reduced post-operative fatigue and convalescence. Although less data is available, similar positive results may be achieved in other types of major surgery. Current research initiatives include improved multi-modal non-opioid analgesia, rational principles for perioperative fluid management, pharmacological reduction of surgical stress responses and the role of laparoscopic procedures within the fast-track concept.Conclusions Fast-track surgery has evolved as a valid concept to improve post-operative outcome. Further progress may be expected based upon intensified research within perioperative pathophysiology and a multi-disciplinary collaboration between surgeons, anaesthesiologists and surgical nurses.  相似文献   
96.
目的观察膝关节关节面在整个运动过程中的应力、应变分布范围、大小及变化规律。方法利用有限元数值模拟方法对行走过程中膝关节关节面应力、应变情况进行分析。结果与结论行走过程中关节面产生应力、应变随时间推移而增加,并且变化规律近似的服从抛物线变化。通过对不同体重的人在行走时膝关节面上产生的应力分析得出,体重对关节面上的应力的大小并不产生重大影响,体重带来的应力差异仅占总应力的10%。  相似文献   
97.
The authors aimed at evaluating the impact of psychotraumas in psychiatric outpatients. One hundred forty psychiatric outpatients were consecutively included, without distinction of their current pathology. They filled in an inventory of potentially traumatic experiences, a psychological dissociative experiences scale, a somatoform dissociative experiences questionnaire, and underwent a structured interview for diagnosis of posttraumatic stress disorder (according to the DSM-IV). One hundred subjects related psychological trauma, and 76 patients suffered from posttraumatic stress disorder. Dissociative disorders are found significantly correlated with traumatic experience and to posttraumatic stress disorder. The traumatic impact is found more substantial as the number of events was elevated. This study confirms the elevated prevalence of the psychological traumas and psychotraumatic aftermaths in outpatients of a department of psychiatry, independently from the mental disorder.  相似文献   
98.
The present study was undertaken to evaluate the role and possible interaction of the endogenous opioid peptide (EOP) and corticotropin-releasing factor (CRF) in the acute stress-induced suppression of gonadotropin secretion in ovariectomized estrogen-primed rats. An intravenous (i.v.) injection of naloxone (10 or 20  mg/kg), an EOP antagonist, significantly elevated serum luteinizing hormone (LH) levels within 10  min in non-stressed animals. The naloxone-induced LH release was completely eliminated when tested 30  min after the onset of acute immobilization. In a subsequent study, it was found that suppression of the naloxone-induced LH release occurred as early as 5  min after the stress onset, and was still evident 60  min after the end of a 30-min period of immobilization. The effect of naloxone was restored 3  h after liberation of the animal from the 30-min immobilization. An intraventricular (i.c.v.) injection of CRF (1 or 5  μg) also significantly suppressed, in a dose-related manner, the effect of a subsequent i.v. injection of naloxone. However, an i.c.v. injection of α -helical CRF(9-41) (25 or 50  μg), a CRF antagonist, prior to immobilization, could not interfere with the suppressive effect of stress on naloxone-induced LH release. These results suggest that both acute immobilization stress and CRF can inhibit the LH secretory activity without mediation by EOP neurons. However, the stress-related suppression may involve non-CRF mechanism(s).  相似文献   
99.
The effects of clinically successful periodontal therapy were studied in juvenile periodontitis (JP) and rapidly progressive periodontitis (RP) patients and compared with periodontally healthy subjects (HS). Serum samples were obtained in 35 HS prior to the study and in 12 of these subjects 3-4 years later. Serum samples were obtained from 50 JP patients initially, 9 subjects immediately following surgical therapy and 29 of these subjects 3-4 years later. RP patients provided 46 initial serum samples, 9 following therapy and 27 samples 3-4 years later. Antibody levels were determined utilizing a standardized enzyme-linked immunosorbent assay with Bacteroides gingivalis, B. ochracea, Fusobacterium nucleatum and Actinobacillus actinomycetemcomitans serving as antigens. The JP patients showed an initial rise in antibody levels immediately following therapy followed by a significant decrease in antibody levels 3 to 4 years later. The RP patients did not show an early change in antibody levels but by 3 to 4 years post-therapy, antibody levels had significantly decreased. However, during this study, the antibody levels of JP and RP patients remained significantly higher when compared with HS patients.  相似文献   
100.
The influence of left ventricular volume variations and regurgitant fraction variations upon left ventricular ejection fraction, during exercise was examined using equilibrium radionuclide angiography in patients suffering from aortic regurgitation. Ejection fraction (EF), regurgitant fraction (RF), end diastolic volume (EDV) and end systolic volume (ESV) variations from rest to peak exercise were determined in 44 patients suffering from chronic aortic regurgitation (AR) and in 8 healthy volunteers (C). In C, EF increased (+0.10±0.03, P<0.01) and ESV decreased significantly (-23%±12%, P<0.01) RF and EDV did not vary significantly. In AR patients, EF, EDV and ESV did not vary significantly because of important scattering of individual values. Changes in EF and ESV were inversely correlated (r=-0.79, P<0.01) and RF decreased significantly (-0.12±0.10, P<0.01). Volumes and EF changes during exercise occurred in three different ways. In a 1st subgroup of 7 patients, EF increased (+0.09±0.03, P<0.05) in conjunction with a reduction of ESV (-24%±12%, P<0.05) without a significant change in EDV. In a 2nd group of 22 patients. EF decreased (-0.04±0.07, P<0.01) in association with an increase in ESV (+17%±16%, P<0.01) and no change in EDV. In a 3rd subgroup of 15 patients, EF decreased (-0.02±0.06, P<0.01) despite a reduction in ESV (-7%±6%, P<0.01) because of a dramatic EDV decrease (-10%±6%, P<0.05). In this subgroup, changes in EF were inversely correlated with changes in ESV (r=-0.55, P<0.01) and positively related to EDV variations (r=0.42, P=0.02). EDV related to EDV variations (r=0.42, P=0.02). EDV changes were weakly, but significantly, correlated to RF decrease (r=0.39, P<0.05). We conclude that changes in left ventricular ejection fraction during exercise in patients with chronic aortic regurgitation are significantly related in some patients to changes in ventricular loading conditions as well as contractile state. Therefore, a correct interpretation of EF changes during exercise requires the simultaneous determination of changes in LV volumes.Abbreviations EDV end diastolic volume - EF ejection fraction - ESV end systolic volume - LV left ventricle - RV right ventricle  相似文献   
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