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91.
The atypical antipsychotic risperidone is often prescribed to pediatric patients with neuropsychiatric disorders, though its effects on the developing brain remain unclear. Accordingly, we studied the effects of repeated treatment of risperidone on dopamine receptors in brain regions of juvenile rat. Levels of dopamine receptors (D(1), D(2), D(3), D(4)) in forebrain regions of juvenile rats were quantified after 3 weeks of treatment with three different doses of risperidone (0.3, 1.0 and 3.0 mg/kg) and compared findings to those in adult rats treated with risperidone (3.0 mg/kg/day) previously. Risperidone (at 1.0 and 3.0 mg/kg/day) increased levels of D(1) receptors in nucleus accumbens and caudate-putamen of juvenile, but not adult rats. Conversely, all three doses of risperidone dose-dependently increased D(2) labeling in medial prefrontal cortex and hippocampus, and D(4) receptor in nucleus accumbens, caudate-putamen and hippocampus of juvenile animals as well as in adults. Only the high dose of risperidone (3.0 mg/kg) increased D(2) receptors in caudate-putamen in both juvenile and adult brain. D(3) receptors were not altered by risperidone in any brain region at any dose or age. The findings indicate dose-dependent effects of risperidone on dopamine receptors in developing animals, and that juvenile animals are more sensitive than adults to the cerebral effects of risperidone.  相似文献   
92.
93.
目的:探讨宫腔镜检查术在辅助生殖技术中应用的重要性。方法:对150例拟行辅助生殖技术的不育妇女行常规宫腔镜检查。结果:宫腔镜150例中47例(31%)有镜下异常,其中:子宫内膜息肉或息肉样增生18例(12%),子宫内膜单纯性增生17例(11%),子宫畸形7例(5%),宫腔粘连狭窄3例(2%),子宫内膜结核1例(0.7%),子宫黏膜下肌瘤或腺肌瘤1例(0.7%)。以宫腔镜诊断为标准,阴道超声诊断敏感性、特异性、阳性预测值、阴性预测值、准确率分别为66%(31/47)、98%(101/103)、94%(31/33)、86%(101/117)、88%(132/150),子宫造影分别为26%(12/47)、100%(95/95)、100%(12/12)、73%(95/130)、75%(107/142)。结论:宫腔镜检查术具有良好的可接受性和准确性,应作为辅助生殖技术前的常规检查。  相似文献   
94.

Background  

Chronic plantar heel pain (CPHP) is one of the most common musculoskeletal disorders of the foot, yet its aetiology is poorly understood. The purpose of this study was to examine the association between CPHP and a number of commonly hypothesised causative factors.  相似文献   
95.
Background  Cardiac resynchronization therapy (CRT) is approved for the treatment of patients with advanced systolic heart failure and evidence of dyssynchrony on electrocardiograms. However, a significant percentage of patients do not demonstrate improvement with CRT. Echocardiographic techniques have been used for more accurate determination of dyssynchrony. Single photon emission computed tomography (SPECT) myocardial perfusion imaging has not previously been used to evaluate cardiac dyssynchrony. The objective of this study is to evaluate mechanical dyssynchrony as described by phase analysis of gated SPECT images in patients with left ventricular dysfunction, conduction delays, and ventricular paced rhythms. Methods and Results  A novel count-based method is used to extract regional systolic wall thickening amplitude and phase from gated SPECT images. Five indices describing the phase dispersion of the onset of mechanical contraction are determined: peak phase, phase SD, bandwidth, skewness, and kurtosis. These indices were determined in consecutive patients with left ventricular dysfunction (n=120), left bundle branch block (n=33), right bundle branch block (n=19), and ventricular paced rhythms (n=23) and were compared with normal control subjects (n=157). Phase SD, bandwidth, skewness, and kurtosis were significantly different between patients with left ventricular dysfunction, left bundle branch block, right bundle branch block, and ventricular paced rhythms and normal control subjects (all P<.001) Peak phase was significantly different between patients with right ventricular paced rhythms and normal control subjects (P=.001). Conclusions  A novel SPECT technique for describing left ventricular mechanical dyssyn-chrony has been developed and may prove useful in the evaluation of patients for CRT. This study was funded in part by a research grant from the Medtronic-Duke Strategic Alliance, of which Dr Borges-Neto is the primary investigator.  相似文献   
96.
彭晋  吴贵华 《医学影像学杂志》2006,16(8):826-826,833
患者男性,29岁。因体检发现纵隔肿物17天入院。无胸、背痛及胸闷、气促、呼吸困难,无咳嗽、咳痰及咯血。查体:生命体征平稳,双肺呼吸音清晰、未闻及干湿性罗音及胸膜摩擦音。胸透及胸部CT:右后下纵隔类圆形占位,密度较均匀,CT值20~22HU,肿物不随呼吸运动活动。CT诊断:右后下纵隔神经源性良性肿瘤(图1,2)。于全麻下行右后下纵隔肿瘤切除术,病理诊断:(右后下纵隔)支气管源性囊肿。讨论:纵隔支气管囊肿属先天性异常,为前肠囊肿的一种,多见于儿童和青年人。大部分位于气管、支气管周围,多在隆突下和右气管旁。最常见的临床症状是胸痛,无症状…  相似文献   
97.
目的 评估单纯行玻璃体切除术对外因性细菌性眼内炎的疗效。方法 外因性细菌性眼内炎21例(21只眼),其中白内障摘除联合人工晶状体植入术后1只眼,眼球穿通伤后20只眼。均作睫状体平部三切口玻璃体切除术,晶状体混浊者一并切除,若有球内异物一并取出,伴视网膜脱离者,重水或气/液交换复位视网膜后行眼内炎光凝、长效气体或硅油填充以及巩膜环扎,术中灌注液内不加入庆大霉素,术毕不作玻璃体腔注药,术后联合抗生索和激素静脉用药。结果 炎症控制20只眼,术后矫正视力提高20只眼,有效率为80.95%。结论 玻璃体切除术对严重细菌性眼内炎而言是最重要的治疗手段。  相似文献   
98.
The levels and temporal variations of surface ozone at a coastal site in East China during summer and autumn were analyzed and the influences of meteorological parameters on ozone were investigated. An inland city was chosen as a comparison site. The main results and conclusions of this study are: (1) ozone pollution, with a maximum 1 h concentration of 150.98 ppbv, was severe during summer and autumn at the coastal site; (2) the ozone level was obviously higher at the coastal site than that at the inland site in September; (3) besides temperature and solar radiation, sea-land breeze circulation is an important factor influencing the ozone level at the coastal site, and sea breeze often induce high ozone levels (the average ozone concentration for sea breeze was about 13 ppbv higher than that for land breeze).  相似文献   
99.
Insulin-like growth factor-1 (Igf-1), a critical mediator of tissue repair, is significantly decreased in diabetic wounds. Furthermore, decreased levels of hypoxia-inducible factor 1-alpha (Hif-1alpha) and its target genes are also associated with impaired wound healing in diabetic mice. The aim of our study was to examine whether the reduced levels of Igf-1 are responsible for the reduction in Hif-1alpha protein synthesis and activity in diabetic wounds. We provide evidence that Igf-1 regulates Hif-1alpha protein synthesis and activity during wound repair. In addition, Igf-1 stimulated phosphytidylinositol 3-kinase activity in diabetic fibroblasts, which, in turn, increased activation of the translational regulatory protein, p70 S6 kinase. Moreover, improved healing of diabetic wounds by addition of recombinant IGF-1 protein was associated with an increase in Hif-1alpha protein synthesis and function in vivo.  相似文献   
100.
Background: The authors determined whether desflurane altered myocardial excitation-contraction coupling and electrophysiologic behavior in the same manner as isoflurane and sevoflurane.

Methods: The effects of desflurane on isometric force in guinea pig ventricular papillary muscles were studied in modified standard and in 26 mm K+ Tyrode solution with 0.1 [mu]m isoproterenol. Desflurane effects on sarcoplasmic reticulum Ca2+ release were also determined by examining its actions on rat papillary muscles, guinea pig papillary muscles in low-Na+ Tyrode solution, and rapid cooling contractures. Normal and slow action potentials were recorded using a conventional microelectrode technique. Ca2+ and K+ currents of guinea pig ventricular myocytes were examined.

Results: Desflurane (5.3% and 11.6%) decreased peak force to approximately 70% and 40% of the baseline, respectively, similar to the effects of equianesthetic isoflurane concentrations. With isoproterenol in 26 mm K+ Tyrode solution, desflurane markedly depressed late peaking force and modestly depressed early peak force. The rested state contractions of rat myocardium or guinea pig myocardium in low-Na+ Tyrode solution were modestly depressed, whereas rapid cooling contractures were virtually abolished after desflurane administration. Desflurane significantly prolonged the action potential duration. Desflurane reduced L-type Ca2+ current and the delayed outward K+ current but did not alter the inward rectifier K+ current.  相似文献   

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