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101.
102.
gamma-Hydroxybutyrate (GHB) is a euphoric, prosocial and sleep inducing drug that binds with high affinity to its own GHB receptor site and also more weakly to GABA(B) receptors. GHB is efficacious in the treatment of narcolepsy and alcoholism, but heavy use can lead to dependence and withdrawal. Many effects of GHB (sedation, hypothermia, catalepsy) are mimicked by GABA(B) receptor agonists (e.g. baclofen). However other effects (euphoric and prosocial effects and a therapeutic effect in narcolepsy) are not. The present study used Fos immunohistochemistry to assess the neural activation produced in rat brain by medium to high doses of GHB (250, 500 and 1000 mg/kg) and a high dose of baclofen (10 mg/kg) that produced similar sedation to 500 mg/kg GHB. Results showed many common regions of activation with these two drugs including the supraoptic, paraventricular, median preoptic and ventral premammillary nuclei of the hypothalamus, the central nucleus of the amygdala, Edinger-Westphal nucleus, lateral parabrachial nucleus, locus coeruleus, and nucleus of the solitary tract. GHB (500 mg/kg), but not baclofen (10 mg/kg), induced significant Fos expression in the median raphe nucleus and lateral habenula, while a higher dose of GHB (1000 mg/kg) induced additional Fos expression in the islands of Calleja, dentate gyrus (polymorphic layer) and arcuate nucleus, and in various regions implicated in rapid and non-rapid eye movement sleep (laterodorsal tegmental nucleus, tuberomammillary nucleus and the ventrolateral and anterodorsal preoptic nuclei). Surprisingly, Fos immunoreactivity was not observed with either GHB or baclofen in reward-relevant regions such as the nucleus accumbens, striatum and ventral tegmental area. Overall these results indicate a distinctive signature of brain activation with GHB that may be only partly due to GABA(B) receptor effects. This confirms a unique neuropharmacological profile for GHB and indicates key neural substrates that may underlie its characteristic influence on sleep, body temperature, sociability and endocrine function. 相似文献
103.
van Nieuwenhuijzen M Orobio de Castro B van Aken MA Matthys W 《Journal of intellectual disability research : JIDR》2009,53(3):233-242
Background A growing interest exists in mechanisms involved in behaviour problems in children with mild intellectual disabilities and borderline intelligence (MID/BI). Social problem solving difficulties have been found to be an explanatory mechanism for aggressive behaviour in these children. However, recently a discrepancy was found between automatic and reflective responding in social situations. We hypothesise that low impulse control and aggressive social problem solving strategies together may explain mechanisms involved in aggressive behaviour by children with MID/BI.
Method In a clinical sample of 130 children with MID/BI receiving intramural treatment, main, moderating and mediating effects of impulse control and aggressive response generation on aggressive behaviour were examined by conducting hierarchical linear multiple regression analyses.
Results Independent main effects of both impulse control and aggressive response generation on aggressive behaviour were found. Results indicated that low impulse control and aggressive response generation each explain unique variance in aggressive behaviour.
Conclusions As this study is the first that has shown both impulse control and aggressive response generation to be important predictors for aggressive behaviour in children with MID/BI, future research should further examine the nature of relations between low impulse control and social problem solving. 相似文献
Method In a clinical sample of 130 children with MID/BI receiving intramural treatment, main, moderating and mediating effects of impulse control and aggressive response generation on aggressive behaviour were examined by conducting hierarchical linear multiple regression analyses.
Results Independent main effects of both impulse control and aggressive response generation on aggressive behaviour were found. Results indicated that low impulse control and aggressive response generation each explain unique variance in aggressive behaviour.
Conclusions As this study is the first that has shown both impulse control and aggressive response generation to be important predictors for aggressive behaviour in children with MID/BI, future research should further examine the nature of relations between low impulse control and social problem solving. 相似文献
104.
目的 探讨应用非每日千伏级锥形束CT(KVCBCT)校位能否改善摆位误差对鼻咽癌调强放疗(IMRT)剂量分布影响。方法 对14例行根治性IMRT的鼻咽癌患者治疗开始后连续5次用KVCBCT检测摆位误差,并将其均值作为系统误差预测值,若其>1.5 mm则在第6次离线校位。假设通过移床能完全校正系统误差,那么从第6次起实际各方向摆位误差值加上离线校位值可得到未行校位时的摆位误差值,在治疗计划系统中通过等中心移位重新计算剂量来模拟应用非每日校位策略前后摆位误差所致的剂量变化。结果 对10例系统误差预测值>1.5 mm者摆位误差明显降低了靶区剂量:98%大体肿瘤体积(GTV)所接受剂量(GTV-D98)平均减少3.8Gy(Z=-2.81,P=0.005),原发灶临床靶体积(CTVns) D95( CTVns-D95)平均减少4.8Gy(Z=-1.96,P=0.050),高危CTV1 -D95平均减少1.0Gy(Z=-2.82,P=0.005),低危CTV2-D95减少不明显(Z=-0.13,P=0.900)。应用非每日校位后明显减少了摆位误差的三维方向位移总量,均值从3.6 mm减少为2.6mm(t=2.00,P=0.000),GTV-D98平均增加3.8 Gy(Z=-2.70,P=0.007),CTVns-D95平均增加5.0Gy(Z=-2.15,P=0.030),CTV1 -D95平均增加0.9Gy(Z=-2.80,P=0.005),减少了危及器官剂量增加>3%、5%患者比例。结论 应用非每日KVCBCT校位能有效减少摆位误差对鼻咽癌IMRT剂量分布的不利影响。 相似文献
105.
目的:分析总结食管癌切除胸腹二区淋巴结清扫的手术疗效。方法:回顾分析1986年2月~2007年12月我院对中下段食管癌和上段食管癌分别采用Ivor—Lewis术式,即上腹正中、右胸后外侧二切口切除及Akiyama术式.即右胸后外侧、上腹正中、左颈部三切口切除,并作胸腹二区淋巴结清扫治疗胸段食管癌1690例的临床资料,总结胸腹二区淋巴结转移的发生率并随访1、3、5年的生存率。结果:全组手术切除率为97.86%(1690/1727)。全组有淋巴结转移782例,占46.27%,其中胸部淋巴结转移占38.93%(658/1690),腹部淋巴结转移占25.92%(438/1690),胸部淋巴结转移发生于最上纵隔位于气管食管沟及喉返神经旁占20.47%(346/1690),术后共有178例发生230例次各种并发症,总的并发症的发生率为13.6%(230/1690),其中肺部并发症为第一位,占34.3%,心律失常占17.4%,喉返神经损伤发生率为8.7%,吻合口瘘发生率为1.7%。术后1、3、5年的生存率分别为88.2%(1161/1316)、63.5%(634/998)和51.8%(331/639)。无淋巴结转移的5年生存率为65.2%(219/336),有淋巴结转移的5年生存率为32.3%(102/316)。结论:Ivor-Lewis术式和Akiyama术式胸腹腔有良好的显露,淋巴结清扫彻底、方便,尤其对右侧最上纵隔沿喉返神经旁淋巴结清扫便利。特别对有淋巴结转移的食管癌患者行胸、腹二区淋巴结清扫十分必要,能明显提高术后5年生存率。 相似文献
106.
107.
Kats S Nieuwenhuijzen GA van Straten BH Schönberger JP 《Interactive Cardiovascular and Thoracic Surgery》2007,6(2):238-239
Transhiatal resection for carcinoma of the distal esophagus is associated with relative high morbidity and mortality. We present a rare case of cardiac tamponade after transhiatal esophagectomy for which emergency sternotomy was performed. Probably the retraction of the heart during exploration of the mediastinum caused a laceration of an epicardial vein. Although very rare, cardiac tamponade should be considered when hemodynamic instability during or after transhiatal esophagectomy occurs. 相似文献
108.
109.
110.
The kinetic occipital (KO) region in man: an fMRI study 总被引:10,自引:8,他引:2
Van Oostende S; Sunaert S; Van Hecke P; Marchal G; Orban GA 《Cerebral cortex (New York, N.Y. : 1991)》1997,7(7):690-701
We used functional magnetic resonance imaging to explore, in individual
subjects, the properties of the kinetic occipital (KO) region, which
previous position emission tomography studies have shown to be involved in
the processing of kinetic boundaries. The KO region was significantly
activated in 23/25 subjects tested in the subtraction of uniform motion
from kinetic gratings. The KO region is genuinely specialized for
processing kinetic boundaries since it is significantly more activated by
kinetic gratings than by luminance-defined gratings, uniform motion or
transparent motion. This leaves only the kinetic boundaries, created by
discontinuities in motion direction, as the specific stimulus aspect,
activating the KO region. The KO region is anatomically and functionally
distinct from areas MT/V5, V3 and V3A. It also has minimal overlap with the
lateral occipital (LO) region. The selective activation of the KO region is
robust and relatively immune to changes in stimulus size, spatial frequency
and type of kinetic boundary. These results strongly argue for the view
that the KO region is a new, separate, functional region in human occipital
cortex.
相似文献