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1.
Interleukin-2 (IL-2) therapy often causes gastrointestinal side effects and at least 8 cases of bowel perforation have been reported. The patient reported here developed a colosplenic fistula, diagnosed by CT, with no neoplastic involvement of these organs. Awareness of these complications of IL-2 can help lead to earlier diagnosis.  相似文献   
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Infection of ryegrass (Lolium perenne) by an endophytic fungus (Acremonium loliae) confers resistance against the Argentine stem weevil (Listronotus bonariensis). Extracts from ryegrass clones, infected and uninfected withA. loliae, were compared in a feeding choice bioassay, and several fractions were identified which affected stem weevil feeding behavior. One stem weevil feeding deterrent, peramine C12H17N5O, has been isolated from infected ryegrass and partially characterized as a basic indole derivative. Extracts from culturedA. loliae had no effect on stem weevil feeding behavior nor was peramine detected in the fungal cultures examined. Peramine and the other active substances are hydrophilic in contrast to the lipophilic properties reported for the neurotoxic lolitrems also isolated from ryegrass infected withA. loliae and associated with causing ryegrass staggers disorder in livestock. It is suggested that ryegrass staggers and stem weevil feeding deterrency may arise by different biochemical mechanisms.  相似文献   
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本文分析了目前无线产品设计面临的挑战,提出了一种只需少量电路,占用较少电路板面积的解决方案,即将功率放大器和前端模块RF装置集成到天线结构的蜂窝无线电天线模块中,针对天线负载条件使天线和RF电路实现最佳匹配。  相似文献   
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杨寓棋   《风景园林》2022,29(1):34-48
由于景观起源、物理环境条件和社会经济发展的差异,在南北半球,学术界对城市生物多样性及其与生态设计方法的相互作用有着不同的理解。数千年来,澳大利亚本土植物群落在这片大陆繁衍生息,形成了生物多样性极高的独特景观。植物园融合自然和人造元素,具有科研和保育功能,其设计与规划反映了科学知识随时间变化的动态特征,也为研究不同社会群体在过去如何利用和重视植物提供了的独特视角,植物园的生态设计方法反映了重视和保护生物多样性的新愿景。以澳大利亚为例,研究并回顾了植物园在保护生物多样性方面的益处,讨论了为展示生物多样性植物园设计重点的变化,分析了澳大利亚植物园的设计历史、澳大利亚本土生物多样性以及以生物多样性为重点的设计解决方案。为了解澳大利亚当地生物多样性和制定植物园示范保护与策略提供研究框架,为重新思考和加强植物园设计中的"生物多样性"提供新视角。  相似文献   
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A 14-year-old girl with congenital heart disease underwent ventricular assist device placement before cardiac transplantation. The inability to close her abdominal fascia necessitated the placement of Prolene mesh, which subsequently became exposed and contaminated when her incision dehisced. Stable closure was obtained with Vicryl mesh and a rectus abdominis turnover flap. Her posttransplant course was notable for compression of the donor heart, necessitating prolonged open sternotomy. She failed an attempt at delayed sternal closure due to compression of the right ventricle by the sternum. In addition to standard pectoralis advancement flaps, a pedicled osseous sternal flap based on her left internal mammary artery was developed to avoid ventricular compression yet still provide some protection to the mediastinum. Alternative uses of this vascularized bone flap to assist with chest wall reconstruction are discussed.  相似文献   
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An in vitro perifusion system was developed for bovine hypothalamic tissue to examine the role of alpha 2-adrenergic receptors in the regulation of growth hormone-releasing hormone (GHRH) and somatostatin (SRIF) release. Up to three sagittal slices (600 microns) of hypothalamus, immediately parallel to the midline, were cut in an oxygenated balanced salt solution at 4 degrees C, placed in 5 cc syringes, and perifused at 37 degrees C with oxygenated minimum essential medium-alpha at a flow rate of 0.15 ml/min. Three experiments were conducted, and medium effluent was collected every 20 min before (two samples), during (one or three samples), and after (six samples) treatment. Areas under GHRH and SRIF response curves (AUC), adjusted by covariance for pretreatment values, were calculated from samples collected during the treatment/post-treatment period. Location from which slices were cut, relative to the sagittal midline, had no effect on basal release of GHRH and SRIF, but variation in basal release of GHRH and SRIF differed among animals. Medium containing 60 mM KCI increased AUC for GHRH 39% and 161% for SRIF when compared with perifusion of medium alone, thereby verifying that tissue remained viable for at least 14 hr. Activation of alpha 2-adrenergic receptor with 10(-6) and 10(-4) M clonidine increased AUC for GHRH from 54.8 (control) to 79.1 and 108.7 +/- 2.5 ng.ml-1 min for 10(-6) M and 10(-4) M clonidine, respectively. Guanabenz, another alpha 2-adrenergic receptor agonist, at 10(-8), 10(-6), and 10(-4) M also increased GHRH release from 45.5 (control) to 52.8, 66.2, and 86.7 +/- 1.6 ng.ml-1 min, respectively. Clonidine and guanabenz did not affect release of SRIF. An alpha 2-adrenergic receptor antagonist, idazoxan, blocked clonidine-induced release of GHRH without affecting release of SRIF. We concluded that alpha 2-adrenergic receptor stimulation of in vivo growth hormone secretion in cattle is mediated via an increase in release of GHRH and not a change in release of SRIF.  相似文献   
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Ilona Gaynor and Benedict Singleton , founding partners of design and research studio The Department of No, look beyond the specific technological possibilities of acute accuracy and explore the principle of zero tolerance as an aesthetic of precision. How is such an aesthetic at work when an architectural strategy places a heightened emphasis on the exact placement of objects in space and time? Could the precision in which a single spatial intervention is pursued have more fundamental and far-reaching consequences than we ever imagined?  相似文献   
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