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91.
Why study transport of peptides and proteins at the neurovascular interface   总被引:2,自引:0,他引:2  
The blood–brain barrier (BBB) is an immense neurovascular interface. In neurodegenerative, ischemic, and traumatic disorders of the central nervous system (CNS), the BBB may hinder the delivery of many therapeutic peptides and proteins to the brain and spinal cord. Fortunately, the mistaken dogma that peptides and proteins do not cross the BBB has been corrected during the past two decades by the accumulating evidence that peptides and proteins in the periphery exert potent effects in the CNS. Not only can peptides and proteins serve as carriers for selective therapeutic agents, but they themselves may directly cross the BBB after delivery into the bloodstream. Their passage may be mediated by simple diffusion or specific transport, both of which can be affected by interactions in the blood compartment (outside the BBB) and within the endothelial cells (at the BBB level). Although the majority of current delivery strategies focuses on modification of the molecule to be delivered, understanding the mechanisms of transport will eventually facilitate regulation of the BBB directly. We review the different aspects of interactions and discuss recent advances in the cell biology of peptide/protein transport across the BBB. Better understanding of the nature and regulation of the transport systems at the BBB will provide a new direction to enhance the interactions of peripheral peptides and proteins with the CNS.  相似文献   
92.
多层螺旋CT尿路造影在尿路梗阻性疾病中的临床应用   总被引:10,自引:1,他引:9  
目的探讨多层螺旋CT尿路造影在泌尿系梗阻性疾病诊断中的应用价值。方法对48例泌尿系统梗阻性疾病者,分别进行多层螺旋CT平扫及多时相期CT增强扫描。对增强后各期图像进行相关处理,以不同的三维重建方式获得CTA、CTU影像。所有病例均经临床及手术证实。结果48例中肾脏及输尿管先天畸形者15例;输尿管阴性结石致肾盂输尿管积水者4例;泌尿系炎症者5例;肾及输尿管、膀胱结核6例;外源性压迫导致肾盂及输尿管积水者8例;泌尿系肿瘤者10例。结论多层螺旋CT泌尿系造影对尿路梗阻性疾病的诊断具有很高的应用价值。  相似文献   
93.
Anesthesia safety for endoscopic laryngeal laser surgery has been a major limiting factor for laser applications in the larynx and the hypopharynx. Several anesthesia techniques have been proposed and each technique appears to have its own limitations. This paper will deal with the distinct advantages offered by the malleable copper tube which is used for delivery of the open Venturi system anesthesia for endoscopic laser surgery. A retrospective study of 100 patients who have undergone this modality of anesthesia at our institution will be presented. Our conclusion from this study shows clearly the superiority of the copper tube over the conventional aluminium-foil-wrapped endotracheal tube in safety and the exposure of the larynx during surgery.  相似文献   
94.
李晴辉  李刚荣  周琳 《重庆医学》2007,36(23):2369-2371
目的本文以医院信息系统(hispitalinformation system,HIS)系统实施的一般规律为例,讨论了HIS系统实施的一般规律,深入探讨了范围变更产生的原因、接受依据以及管理技术,对于HIS系统实施中最常发生的范围变更管理提出了对策,以使医院业务与HIS软件系统有机会结合在一起,真正实现医院业务信息化的目标。方法文章认为,系统范围变更管理应贯穿于系统实施过程的始终,每一项需求变更都应分析其产生的原因、对医院业务的影响和对系统实施的影响,以确定是否接受范围变更。结果当决定接受或拒绝范围变更申请时,信息科都应与提供产品公司的实施工程师沟通。结论在范围变更管理中,要充分使用好文档模板,并制定出规范的范围变更管理流程,以提高范围变更管理效率。  相似文献   
95.
In glaucomatous eyes refractory to medication, laser techniques and conventional drainage surgery, intraocular pressure is often high, and visual loss rapid. In this situation a reliable, robust artificial outflow system is required. Molteno has evolved a plastic tube and plate device combined with a fibrosis suppression medication regimen. Thirty-eight eyes of 32 patients with uncontrolled glaucoma were treated with the Molteno system. Six months after operation mean intraocular pressure had been reduced from 41.0 ± 13.6 to 16.2 ± 5.6 mmHg. Eighteen eyes had pressures of 20 mmHg or less on no hypotensive therapy, 17 on reduced treatment. Three eyes had a pressure of 21 to 35 mmHg on treatment at six months. The 13 aphakic eyes responded as well as 25 phakic eyes. Five eyes with rubeotic glaucoma demonstrated pressures of less than 20 mmHg without therapy, four eyes with traumatic glaucoma required continuing medication with three having pressures below 22 mmHg. Of the seven eyes with uveitic glaucoma, one was lost, two required maintenance therapy; five of six surviving eyes had pressures below 20 mmHg. Fifteen eyes with congenital or juvenile glaucoma achieved pressures below 20 mmHg, three of these with timolol drops, three with timolol and acetazolamide, and nine with no treatment. While seven of seven eyes with refractory primary open-angle glaucoma attained pressures below 20 mmHg. all seven needed continuing mild hypotensive therapy. Eleven eyes underwent a one-stage procedure, while 27 eyes required a two-stage operation. Twenty-eight eyes received fibrosis suppression medication after the second stage, and 24 maintained or improved their preoperative visual acuity. Results have been encouraging: in general the Molteno system is recommended as the second drainage operation in all glaucomatous eyes in which conventional therapy has failed, and as the primary surgical procedure (after laser techniques) in eyes with rubeotic and uveitic glaucoma. Ciliary body destructive procedures should be restricted to control of symptoms in blind eyes.  相似文献   
96.
橄榄油对单核吞噬细胞系统的影响   总被引:1,自引:0,他引:1  
本文采用橄榄油皮下注射、观察其对小鼠腹腔单核吞噬细胞的游出、活化及吞噬功能。结果发现、橄榄油对上述功能均有明显的抑制作。  相似文献   
97.
98.
We previously reported that the Guardian Bio-Threat Alert (BTA) system could detect (detection limit: about 0.1 μg/ml) staphylococcal enterotoxin B (SEB), botulinum toxins (BTX) A and B, and ricin, with no interference by white-powdered materials or colored matrices. In this study, the capability of the BTA system was further assessed. With 10 min of preheating at 60°C, all toxins could be detected, but with preheating at 80°C, BTX A and B and ricin became undetectable. About 20% SEB could be detected after heating at 80°C, but this detection ability was completely removed after heating at 100°C. The effects of chemicals usually used for decontamination, such as sodium hypochlorite, hydrogen peroxide, formaldehyde, and sodium nitrite, on the detectability of SEB, BTX A, or ricin in the BTA system were also tested. The concentrations giving 50% line intensity for SEB, BTX A, and ricin were 3.1, 11, and 15 μM for sodium hypochlorite and 88, 210, and 60 mM for formaldehyde, respectively. The addition of hydrogen peroxide or sodium nitrite did not decrease the detectability even when used at high concentrations.  相似文献   
99.
目的回顾性总结手术治疗完全性房室间隔缺损的经验。方法112例病儿,≤6个月43例(38%,X组),>6个月69例(62%,Y组)。85例行心导管检查。Rastelli A型89例,Rastelli B型10例,Ras- telli C型13例。手术技术分单片法,双片法和简化单片法。术中经食管超声检查发现异常而即刻再次手术者7例(二尖瓣反流4例,二尖瓣狭窄2例,左室流出道梗阻1例)。术后入重症监护室,左房压8~21 mm Hg,中心静脉压7~12mm Hg。呼吸机平均应用47h,监护室平均滞留6.3d。结果室间隔缺损残余分流(直径>2mm)13例,二尖瓣中度反流12例,完全性房室传导阻滞4例。院内死亡6例(X组1例,Y组5例)。术后随访91例(81%),随访1~5年,平均2.3年。1例术后1年因肺炎心衰死亡,1例术后2年因二尖瓣中-重度反流而换瓣。结论院内死亡率提示,小于6月龄完全性房室间隔缺损病婴手术是安全的。随着年龄增大,瓣膜成形效果、肺动脉高压的预后可能会更差。双片法修补室间隔缺损较易发生残余漏(9例,18%),简化单片法出院时二尖瓣关闭不全发生率明显高于另外两种方法(6例,16%)。  相似文献   
100.
AIMS: This study evaluates feasibility, safety, and efficacy of magnetic remote-controlled accessory pathway (AP) ablation. METHODS AND RESULTS: The novel magnetic navigation system (MNS) (Niobe, Stereotaxis) creates a steerable magnetic field (0.08 T) controlling the distal magnetic tip of an ablation catheter. In conjunction with a catheter advancer system (Cardiodrive, Stereotaxis) remote catheter ablation is enabled. Conventional electrophysiology study identified AP conduction in 59 patients (37 males, 36+/-14 years, 60 APs). First generation 1-magnet tip (1-M) (group I, n=18), second generation bipolar 3-magnet tip (3-M) (group II, n=27), and third generation quadripolar 3-magnet tip catheters (3-M quad.) (group III, n=14) were used for magnetic remote-controlled ablation. Successful AP ablation was achieved in 67% (group I), 85% (group II), and 92% (group III). A significant decrease of median [IQR: Q1-Q3] fluoroscopy time and dosage was observed: 21.2 [12.1-33.8] min, 1110 [395-3234] microGym2 (group I); 6.5 [4.4-15.4] min, 290 [129-489] microGym2 (group II), and 4.9 [3.4-8.0] min, 129 [74-270] microGym2 (group III). Mean procedure time (217+/-67 min; 182+/-68 min, and 172+/-90 min) significantly decreased in group III. Median number [Q1-Q3] of radiofrequency current applications in groups I, II, and III was 4 [2-9], 4 [2-6], and 2 [2-4], respectively. No complications occurred. CONCLUSION: Remote AP ablation is safe and feasible using the novel MNS. Introduction of the 3-magnet quadripolar ablation catheter significantly improved the efficacy of the procedure.  相似文献   
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