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1.
目的 依据髌周解剖学特点,探讨全膝关节置换术(total knee arthroplasty,TKA)中应用髌周电灼去神经化的临床效果。 方法 纳入82名诊断为骨性关节炎的患者(91膝),予行双侧或单侧不置换髌骨的TKA,按随机对照原则将病人分为两组,共有41名实验组患者(45膝)在TKA中接受了髌周去神经化处理,41名对照组患者(46膝)未做该处理。手术主刀为同一骨科医师,均使用相同的膝关节假体系统。主要评价项目包括膝关节KSS评分、Western Ontario and McMaster Universities(WOMAC)、Feller髌骨评分及VAS评分。 结果 82名患者术后均获随访,平均随访时间为12个月,两组病人的膝关节KSS评分、WOMAC、Feller髌骨评分及VAS评分均无显著统计学差异(P>0.05)。 结论 在TKA中行髌周电灼去神经化,不能显著改善病人的预后。 相似文献
2.
Renal Denervation for Treatment of Cardiac Arrhythmias: State of the Art and Future Directions
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JEDRZEJ KOSIUK M.D. SEBASTIAN HILBERT M.D. EVGENY POKUSHALOV M.D. GERHARD HINDRICKS M.D. Ph.D. JONATHAN S. STEINBERG M.D. ANDREAS BOLLMANN M.D. Ph.D. 《Journal of cardiovascular electrophysiology》2015,26(2):233-238
Renal Denervation for Treatment of Cardiac Arrhythmias . It has now been more than a quarter of a century since modulation of the sympathetic nervous system was proposed for the treatment of cardiac arrhythmias of different origins. But it has also been some time since some of the early surgical attempts have been abandoned. With the development of ablation techniques, however, new approaches and targets have been recently introduced that have revolutionized our way of thinking about sympathetic modulation. Renal nerve ablation technology is now being successfully used for the treatment of resistant hypertension, but the indication spectrum might broaden and new therapeutic options might arise in the near future. This review focuses on the possible impact of renal sympathetic system modulation on cardiac arrhythmias, the current evidence supporting this approach, and the ongoing trials of this method in electrophysiological laboratories. We will discuss the potential roles that sympathetic modulation may play in the future. 相似文献
3.
Quantitative chemical exchange saturation transfer (qCEST) MRI – omega plot analysis of RF‐spillover‐corrected inverse CEST ratio asymmetry for simultaneous determination of labile proton ratio and exchange rate
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Renhua Wu Gang Xiao Iris Yuwen Zhou Chongzhao Ran Phillip Zhe Sun 《NMR in biomedicine》2015,28(3):376-383
Chemical exchange saturation transfer (CEST) MRI is sensitive to labile proton concentration and exchange rate, thus allowing measurement of dilute CEST agent and microenvironmental properties. However, CEST measurement depends not only on the CEST agent properties but also on the experimental conditions. Quantitative CEST (qCEST) analysis has been proposed to address the limitation of the commonly used simplistic CEST‐weighted calculation. Recent research has shown that the concomitant direct RF saturation (spillover) effect can be corrected using an inverse CEST ratio calculation. We postulated that a simplified qCEST analysis is feasible with omega plot analysis of the inverse CEST asymmetry calculation. Specifically, simulations showed that the numerically derived labile proton ratio and exchange rate were in good agreement with input values. In addition, the qCEST analysis was confirmed experimentally in a phantom with concurrent variation in CEST agent concentration and pH. Also, we demonstrated that the derived labile proton ratio increased linearly with creatine concentration (P < 0.01) while the pH‐dependent exchange rate followed a dominantly base‐catalyzed exchange relationship (P < 0.01). In summary, our study verified that a simplified qCEST analysis can simultaneously determine labile proton ratio and exchange rate in a relatively complex in vitro CEST system. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
4.
Fast CT-PRESS-based spiral chemical shift imaging at 3 Tesla. 总被引:2,自引:0,他引:2
Dirk Mayer Dong-Hyun Kim Elfar Adalsteinsson Daniel M Spielman 《Magnetic resonance in medicine》2006,55(5):974-978
A new sequence is presented that combines constant-time point-resolved spectroscopy (CT-PRESS) with fast spiral chemical shift imaging. It allows the acquisition of multivoxel spectra without line splitting with a minimum total measurement time of less than 5 min for a field of view of 24 cm and a nominal 1.5x1.5-cm2 in-plane resolution. Measurements were performed with 17 CS encoding steps in t1 (Deltat1=12.8 ms) and an average echo time of 151 ms, which was determined by simulating the CT-PRESS experiment for the spin systems of glutamate (Glu) and myo-inositol (mI). Signals from N-acetyl-aspartate, total creatine, choline-containing compounds (Cho), Glu, and mI were detected in a healthy volunteer with no or only minor baseline distortions within 14 min on a 3 T MR scanner. 相似文献
5.
综述了C_(60)化学研究的进展。C_(60)的化学反应性的研究展现了一个广阔的新领域,并使C_(60)作为一种新型的功能基团引入高分子成为现实。这些进展为进一步深入研究C_(60)尤其是C_(60)的材料化提供了前提。 相似文献
6.
Mr. Charles V. Clark M.D. David J. Ewing 《Documenta ophthalmologica. Advances in ophthalmology》1988,70(4):309-321
Ocular autonomic function was assessed in 4 patients with progressive autonomic failure (PAF) and age-matched control subjects, by measurement of the pupil cycle time, and determination of autonomic denervation hypersensitivity of the iris. Pupil cycle time was abnormal in all patients with PAF; sustained pupil cycling was absent in 5 of the 8 eyes tested of the PAF patients, compared with only 16 eyes from 70 control subjects. Pupil constriction in response to 2.5% methacholine, indicative of parasympathetic denervation hypersensitivity, was significantly increased in patients with PAF (p < 0.001), whilst pupil dilation in response to 0.5% phenylephrine, indicative of sympathetic denervation hypersensitivity, was also significantly higher in the PAF patients (p < 0.001). The results suggest that ocular autonomic function may provide a sensitive early indicator of generalised autonomic dysfunction. 相似文献
7.
J. Carleson P. Kogner I. Bileviciute E. Theodorsson A. Appelgren B. Appelgren S. Kopp N. Yousef T. Lundeberg 《Archives of oral biology》1997,42(12):869-876
Temporomandibular joint (TMJ) arthritis was induced in female Lewis rats by unilateral injection of a suspension of heat-killed Mycobacterium butyricum in paraffin oil into the TMJ. Control rats received paraffin oil by the same route. Arthritic and control rats were pretreated either with capsaicin or denervation of the mandibular branch of the trigeminal nerve. Tissues were collected for neuropeptide extraction and analysed by radioimmunoassay and reverse-phase high-performance liquid chromatography. In all groups, the levels of substance P- (SP), calcitonin gene-related peptide- (CGRP) and neuropeptide Y- (NPY) like immunoreactivity (LI) were higher in the trigeminal ganglia than in the TMJs. In control rats, capsaicin significantly lowered the levels of SP-LI in the trigeminal ganglia and TMJ, but not CGRP-LI and NPY-LI. In the arthritic rats, capsaicin pretreatment significantly lowered the SP-LI and CGRP-LI in the trigeminal ganglia and TMJ, but not the NPY-LI. In the trigeminal ganglia the unilateral denervation significantly lowered SP-LI in control rats, and in arthritic rats SP-LI and CGRP-LI. On the denervated side of the arthritic TMJ, NPY-LI, SP-LI and CGRP- LI were significantly lowered as compared to the arthritic control rats and to the contralateral side. In this rat model, pretreatment with capsaicin and surgical denervation decreased the neuropeptide content in the trigeminal ganglia and the TMJ. The results clearly demonstrate a close interaction between increased neuropeptide release from sensory and sympathetic neurones after induction of arthritis in the rat. 相似文献
8.
9.
Abstract: Native chemical ligation has proven to be a powerful method for the synthesis of small proteins and the semisynthesis of larger ones. The essential synthetic intermediates, which are C‐terminal peptide thioesters, cannot survive the repetitive piperidine deprotection steps of Nα‐9‐fluorenylmethoxycarbonyl (Fmoc) chemistry. Therefore, peptide scientists who prefer to not use Nα‐t‐butyloxycarbonyl (Boc) chemistry need to adopt more esoteric strategies and tactics in order to integrate ligation approaches with Fmoc chemistry. In the present work, side‐chain and backbone anchoring strategies have been used to prepare the required suitably (partially) protected and/or activated peptide intermediates spanning the length of bovine pancreatic trypsin inhibitor (BPTI). Three separate strategies for managing the critical N‐terminal cysteine residue have been developed: (i) incorporation of Nα‐9‐fluorenylmethoxycarbonyl‐S‐(N‐methyl‐N‐phenylcarbamoyl)sulfenylcysteine [Fmoc‐Cys(Snm)‐OH], allowing creation of an otherwise fully protected resin‐bound intermediate with N‐terminal free Cys; (ii) incorporation of Nα‐9‐fluorenylmethoxycarbonyl‐S‐triphenylmethylcysteine [Fmoc‐Cys(Trt)‐OH], generating a stable Fmoc‐Cys(H)‐peptide upon acidolytic cleavage; and (iii) incorporation of Nα‐t‐butyloxycarbonyl‐S‐fluorenylmethylcysteine [Boc‐Cys(Fm)‐OH], generating a stable H‐Cys(Fm)‐peptide upon cleavage. In separate stages of these strategies, thioesters are established at the C‐termini by selective deprotection and coupling steps carried out while peptides remain bound to the supports. Pilot native chemical ligations were pursued directly on‐resin, as well as in solution after cleavage/purification. 相似文献
10.
Javairiah Fatima Scott G. Houghton Michael G. Sarr 《Journal of gastrointestinal surgery》2007,11(8):1052-1056
Small bowel transplantation (SBT) is associated with poorly understood enteric dysfunction. The study of SBT in mice is hindered
by the technical difficulty of orthotopic SBT in the mouse. Our aim was to develop an easy preparation of extrinsic denervation
of the entire jejunoileum in mice as a model of orthotopic SBT. All neurolymphatic tissues accompanying the superior mesenteric
artery (SMA) and vein (SMV) were ligated just distal to the middle colic vessels. The SMA and SMV were then stripped of investing
adventitia, and the mesentery to jejunum and colon were transected radially. Jejunum and colon were not transected and reanastomosed.
To confirm extrinsic denervation 1, 3, and 6 months later, segments of small bowel were stained for protein gene product 9.5
(PGP9.5) and tyrosine hydroxylase (TH). Tyrosine hydroxylase immunoreactive intensity was then quantified using a semiquantitative
analysis. Immunohistochemical fluorescence showed persistence of PGP9.5 immunoreactivity confirming enteric nerves in jejunoileum;
however, there was no TH immunoreactivity in jejunoileum in denervated mice despite the expected preservation of TH immunoreactivity
in the still-innervated duodenum at 1 month. At 3 months, sparse immunoreactivity for TH was present, and by 6 months, reinnervation
of TH-containing nerves appeared similar to controls. Quantification of intensity at each time-point further confirmed this
trend. This technique in the mouse accomplishes a complete extrinsic denervation of jejunoileum early postoperatively (1 and
3 months); reinnervation occurs by 6 months. This is an easily learned murine model of orthotopic SBT.
Presented at the American Gastroenterological Association during Digestive Disease Week in Los Angeles, CA, as a poster presentation
on May 23 2006. Abstract published in GastroenterologyE 2006; 130:A604. 相似文献