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702.
AD Houghton MS FRCS Y Panayiotopoulos MD PhD PR Taylor mchir FRCS 《International journal of clinical practice》1996,50(2):103-105
SUMMARY Varicose veins cause a great deal of morbidity in our population today. Despite the large amount of surgical time spent dealing with the problem, there is still a disappointingly high recurrence rate and many patients are investigated inadequately before surgery. This review considers the assessment of ‘simple’ varicose veins using a combination of tourniquet tests and a hand-held doppler probe. The place of more sophisticated investigative techniques is also discussed, in particular the value of duplex assessment in localising the variably sited sapheno-popliteal junction. Routine stripping of the long saphenous vein to the below-knee level is likely to decrease the recurrence rate of simple, long, saphenous varicose veins. 相似文献
703.
系统观察使用异搏停停跳液的34例体外循环病例,6例(17.6%)在10~38分钟复跳。延迟复跳组和非延迟复跳组间不存在血钙等特异性因素的影响,而受年龄、心脏缺血时间和心脏张力的影响。延迟复跳心脏的功能良好,超微结构保护良好。作者对异搏停液的使用指征和延迟复跳的处理提出了建议。 相似文献
704.
Maria Papaiordanidou PHD Valérie Mustacchi MSC Jean‐Damien Stevenot MSC Michele Vanoncini PHD Alain Martin PR 《Muscle & nerve》2016,53(4):626-632
Introduction: We examined the neural mechanisms responsible for plantar flexion torque changes at different joint positions. Methods: Nine subjects performed maximal voluntary contractions (MVC) at 6 ankle–knee angle combinations [3 ankle angles (dorsiflexion, anatomic position, plantar flexion) and 2 knee angles (flexion, full extension)]. Neural mechanisms were determined by V‐wave, H‐reflex (at rest and during MVC), and electromyography during MVC (RMS), normalized to the muscle compound action potential (V/Msup, Hmax/Mmax, Hsup/Msup and RMS/Msup) and voluntary activation (VA), while muscle function was assessed by doublet amplitude. Results: MVC and doublet amplitude were significantly lower at plantar flexion (P < 0.01), while VA was significantly lower at dorsiflexion and full knee extension (P < 0.05). V/Msup and RMS/Msup were significantly lower at knee extension (P < 0.01), while Hsup/Msup was not affected by joint angle. Conclusions: These results indicate that joint positions leading to muscle lengthening produce reduced neural drive, due mainly to supraspinal mechanisms. Muscle Nerve 53 : 626–632, 2016 相似文献
705.
黄嘌呤氧化酶对血管内皮功能障碍的影响 总被引:3,自引:0,他引:3
目的考察黄嘌呤氧化酶(xanthine oxidase)在自发性高血压大鼠(SHR)血管舒缩及内皮功能障碍中的作用。方法采用尾套法测定SHR和正常大鼠(WKY)血压;Greiss反应测定血清一氧化氮分泌量;FRAP(ferric reduction abilitypower)法测定主动脉蛋白总抗氧化能力;RT-PCR法考察黄嘌呤氧化酶及内皮型一氧化氮合酶(eNOS)mRNA表达情况;血管环舒缩测定来评价黄嘌呤氧化酶抑制剂别嘌呤醇(oxypurinol,Oxy)对大鼠腹主动脉内皮依赖性舒张反应的影响。结果SHR血压(191.1±5.6)显著高于WKY大鼠(140.4±5.9)mmHg;SHR血清NO分泌量(28.4±5.4)、主动脉蛋白总抗氧化能力(1.02±0.14)U/μg蛋白和腹主动脉内皮依赖性舒张反应(66.2±4.6)%均显著低于WKY[分别为(51.6±5.8),(2.8±0.3)U/μgpro和81.0%±2.7%);而心、肾及主动脉中黄嘌呤氧化酶表达均显著高于WKY大鼠(P<0.05)。黄嘌呤氧化酶抑制剂Oxy能明显降低黄嘌呤氧化酶mRNA表达(降低31.6%),且改善腹主动脉内皮依赖型舒张反应(提高20.2%),但对eNOS表达则无显著影响。结论结果提示SHR中存在内皮功能障碍和氧化应激状态,黄嘌呤氧化酶参与了SHR内皮功能障碍。 相似文献
706.
707.
Pancreatic necrosis: CT manifestations 总被引:2,自引:0,他引:2
White EM; Wittenberg J; Mueller PR; Simeone JF; Butch RJ; Warshaw AL; Neff CC; Nardi GL; Ferrucci JT Jr 《Radiology》1986,158(2):343-346
Pancreatic necrosis is a potential sequela of acute pancreatitis, which pathologically represents a collection of devitalized tissue. Appropriate therapeutic planning requires definition of this irreversibly damaged gland, the presence of which is not consistently diagnosed on the basis of clinical and laboratory data. Over an 18-month period, 22 patients with pancreatic necrosis were studied by one or more computed tomographic (CT) examinations. Retrospective analysis showed the findings to vary with the developmental stage of the necrotizing process. During the acute phase, there was considerable morphologic overlap of necrosis and pancreatic phlegmon. Typical findings were seen in the subacute and chronic stages and included diffuse enlargement of the gland with largely decreased central density. A thick, smooth surrounding rim produced a characteristic saclike configuration. CT-guided aspiration for culture material was performed in four patients with suspected superinfection. Negative gram stain and culture results in two patients allowed surgery to be performed on a more elective basis. 相似文献
708.
Aki Morikawa David M. Peereboom Helen R. Thorsheim Ramakrishna Samala Rajiv Balyan Conleth G. Murphy Paul R. Lockman Ahkeem Simmons Robert J. Weil Viviane Tabar Patricia S. Steeg Quentin R. Smith Andrew D. Seidman 《Neuro-oncology》2015,17(2):289-295
BackgroundBreast cancer brain metastases (BCBM) are challenging complications that respond poorly to systemic therapy. The role of the blood–tumor barrier in limiting BCBM drug delivery and efficacy has been debated. Herein, we determined tissue and serum levels of capecitabine, its prodrug metabolites, and lapatinib in women with BCBM resected via medically indicated craniotomy.MethodsStudy patients with BCBM requiring surgical resection received either single-dose capecitabine (1250 mg/m2) 2–3 h before surgery or 2–5 doses of lapatinib (1250 mg) daily, the last dose 2–3 h before surgery. Serum samples were collected serially on the day of surgery. Drug concentrations were determined in serum and BCBM using liquid chromatography tandem mass spectrometry.ResultsTwelve patients were enrolled: 8 for capecitabine and 4 for lapatinib. Measurable drug levels of capecitabine and metabolites, 5′-deoxy-5-fluorocytidine, 5′-deoxy-5-fluorouridine, and 5-fluorouracil, were detected in all BCBM. The ratio of BCBM to serum was higher for 5-fluorouracil than for capecitabine. As for lapatinib, the median BCBM concentrations ranged from 1.0 to 6.5 µM. A high variability (0.19–9.8) was noted for lapatinib BCBM-to-serum ratio.ConclusionsThis is the first study to demonstrate that capecitabine and lapatinib penetrate to a significant though variable degree in human BCBM. Drug delivery to BCBM is variable and in many cases appears partially limiting. Elucidating mechanisms that limit drug concentration and innovative approaches to overcome limited drug uptake will be important to improve clinical efficacy of these agents in the central nervous system.Trial registration ID: . NCT00795678相似文献
709.
710.
Oral Diseases (2011) 17 , 241–251 The rapid advancement in basic biology knowledge, especially in the stem cell field, has created new opportunities to develop biomaterials capable of orchestrating the behavior of transplanted and host cells. Based on our current understanding of cellular differentiation, a conceptual framework for the use of materials to program cells in situ is presented, namely a domino vs a switchboard model, to highlight the use of single vs multiple cues in a controlled manner to modulate biological processes. Further, specific design principles of material systems to present soluble and insoluble cues that are capable of recruiting, programming and deploying host cells for various applications are presented. The evolution of biomaterials from simple inert substances used to fill defects, to the recent development of sophisticated material systems capable of programming cells in situ is providing a platform to translate our understanding of basic biological mechanisms to clinical care. 相似文献