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51.
52.
Unicompartmental knee arthroplasty: Is robotic technology more accurate than conventional technique?
Mustafa Citak Eduardo M. Suero Musa Citak Nicholas J. Dunbar Sharon H. Branch Michael A. Conditt Scott A. Banks Andrew D. Pearle 《The Knee》2013,20(4):268-271
BackgroundRobotic-assisted unicompartmental knee arthroplasty (UKA) with rigid bone fixation "can significantly improve implant placement and leg alignment. The aim of this cadaveric study was to determine whether the use of robotic systems with dynamic bone tracking would provide more accurate UKA implant positioning compared to the conventional manual technique.MethodsThree-dimensional CT-based preoperative plans were created to determine the desired position and orientation for the tibial and femoral components. For each pair of cadaver knees, UKA was performed using traditional instrumentation on the left side and using a haptic robotic system on the right side. Postoperative CT scans were obtained and 3D-to-3D iterative closest point registration was performed. Implant position and orientation were compared to the preoperative plan.ResultsSurgical RMS errors for femoral component placement were within 1.9 mm and 3.7° in all directions of the planned implant position for the robotic group, while RMS errors for the manual group were within 5.4 mm and 10.2°. Average RMS errors for tibial component placement were within 1.4 mm and 5.0° in all directions for the robotic group; while, for the manual group, RMS errors were within 5.7 mm and 19.2°.ConclusionsUKA was more precise using a semiactive robotic system with dynamic bone tracking technology compared to the manual technique. 相似文献
53.
Turkeltaub PE Coslett HB Thomas AL Faseyitan O Benson J Norise C Hamilton RH 《Cortex; a journal devoted to the study of the nervous system and behavior》2012,48(9):1179-1186
Neurologists and aphasiologists have debated for over a century whether right hemisphere recruitment facilitates or impedes recovery from aphasia. Here we present a well-characterized patient with sequential left and right hemisphere strokes whose case substantially informs this debate. A 72-year-old woman with chronic nonfluent aphasia was enrolled in a trial of transcranial magnetic stimulation (TMS). She underwent 10 daily sessions of inhibitory TMS to the right pars triangularis. Brain activity was measured during picture naming using functional magnetic resonance imaging (fMRI) prior to TMS exposure and before and after TMS on the first day of treatment. Language and cognition were tested behaviorally three times prior to treatment, and at 2 and 6 months afterward. Inhibitory TMS to the right pars triangularis induced immediate improvement in naming, which was sustained 2 months later. fMRI confirmed a local reduction in activity at the TMS target, without expected increased activity in corresponding left hemisphere areas. Three months after TMS, the patient suffered a right hemisphere ischemic stroke, resulting in worsening of aphasia without other clinical deficits. Behavioral testing 3 months later confirmed that language function was impacted more than other cognitive domains. The paradoxical effects of inhibitory TMS and the stroke to the right hemisphere demonstrate that even within a single patient, involvement of some right hemisphere areas may support recovery, while others interfere. The behavioral evidence confirms that compensatory reorganization occurred within the right hemisphere after the original stroke. No support is found for interhemispheric inhibition, the theoretical framework on which most therapeutic brain stimulation protocols for aphasia are based. 相似文献
54.
Sonia S. Anand Francois Caron John W. Eikelboom Jackie Bosch Leanne Dyal Victor Aboyans Maria Teresa Abola Kelley R.H. Branch Katalin Keltai Deepak L. Bhatt Peter Verhamme Keith A.A. Fox Nancy Cook-Bruns Vivian Lanius Stuart J. Connolly Salim Yusuf 《Journal of the American College of Cardiology》2018,71(20):2306-2315
Background
Patients with lower extremity peripheral artery disease (PAD) are at increased risk of major adverse cardiovascular events (MACE) and major adverse limb events (MALE). There is limited information on the prognosis of patients who experience MALE.Objectives
Among participants with lower extremity PAD, this study investigated: 1) if hospitalizations, MACE, amputations, and deaths are higher after the first episode of MALE compared with patients with PAD who do not experience MALE; and 2) the impact of treatment with low-dose rivaroxaban and aspirin compared with aspirin alone on the incidence of MALE, peripheral vascular interventions, and all peripheral vascular outcomes over a median follow-up of 21 months.Methods
We analyzed outcomes in 6,391 patients with lower extremity PAD who were enrolled in the COMPASS (Cardiovascular Outcomes for People Using Anticoagulation Strategies) trial. COMPASS was a randomized, double-blind placebo-controlled study of low-dose rivaroxaban and aspirin combination or rivaroxaban alone compared with aspirin alone. MALE was defined as severe limb ischemia leading to an intervention or major vascular amputation.Results
A total of 128 patients experienced an incident of MALE. After MALE, the 1-year cumulative risk of a subsequent hospitalization was 61.5%; for vascular amputations, it was 20.5%; for death, it was 8.3%; and for MACE, it was 3.7%. The MALE index event significantly increased the risk of experiencing subsequent hospitalizations (hazard ratio [HR]: 7.21; p < 0.0001), subsequent amputations (HR: 197.5; p < 0.0001), and death (HR: 3.23; p < 0.001). Compared with aspirin alone, the combination of rivaroxaban 2.5 mg twice daily and aspirin lowered the incidence of MALE by 43% (p = 0.01), total vascular amputations by 58% (p = 0.01), peripheral vascular interventions by 24% (p = 0.03), and all peripheral vascular outcomes by 24% (p = 0.02).Conclusions
Among individuals with lower extremity PAD, the development of MALE is associated with a poor prognosis, making prevention of this condition of utmost importance. The combination of rivaroxaban 2.5 mg twice daily and aspirin significantly lowered the incidence of MALE and the related complications, and this combination should be considered as an important therapy for patients with PAD. (Cardiovascular Outcomes for People Using Anticoagulation Strategies [COMPASS]; NCT01776424) 相似文献55.
慢性便秘中医诊疗共识意见 总被引:14,自引:0,他引:14
中华中医药学会脾胃病分会 《北京中医药》2011,30(1):3-7
慢性便秘(Chronic Constipation)是临床常见病和多发病。近年来,西医制定了慢性便秘的诊疗标准与指南[1-2],而对作为中医药治疗优势病种之一的慢性便秘中医领域却尚未形成共识。2008年开始,中华中医药学会脾胃病分会组织成立"慢性便秘中医诊疗共识意见"起草小组,在充分地讨论后,结合国内 相似文献
56.
基于对中药酊剂外用技术的数据挖掘,结合临床实际应用研究,经外治学会专家多次论证,形成中药酊剂临床外用技术规范(草案),包括临床适用范围、操作步骤以及外用酊剂的方法、剂量、频率、时间、注意事项、不良反应及护理要点。以期规范中药外用酊剂的临床应用,提高其疗效并减少不良反应。 相似文献
57.
de Jong A Peña-Cruz V Cheng TY Clark RA Van Rhijn I Moody DB 《Nature immunology》2010,11(12):1102-1109
CD1 activates T cells, but the function and size of the possible human T cell repertoires that recognize each of the CD1 antigen-presenting molecules remain unknown. Using an experimental system that bypasses major histocompatibility complex (MHC) restriction and the requirement for defined antigens, we show that polyclonal T cells responded at higher rates to cells expressing CD1a than to those expressing CD1b, CD1c or CD1d. Unlike the repertoire of invariant natural killer T (NKT) cells, the CD1a-autoreactive repertoire contained diverse T cell antigen receptors (TCRs). Functionally, many CD1a-autoreactive T cells homed to skin, where they produced interleukin 22 (IL-22) in response to CD1a on Langerhans cells. The strong and frequent responses among genetically diverse donors define CD1a-autoreactive cells as a normal part of the human T cell repertoire and CD1a as a target of the T(H)22 subset of helper T cells. 相似文献
58.
血脂测定结果的临床可接受性分析 总被引:3,自引:2,他引:3
目的:通过对不同检测系统血脂测定结果的偏倚评估,分析各系统间结果的可比性和临床可接受性。方法:参照CLSI文件相关要求,以可溯源的检测系统为目标检测系统,测定总胆固醇(TCH)、甘油三酯(TG)、载脂蛋白A1(APOA1)、载脂蛋白B(APOB)、高密度脂蛋白胆固醇(HDL-C)和低密度脂蛋白胆固醇(LDL-C),对本院3个不同检测系统进行朗道质控物(水平2和水平3)各测定21次和测定新鲜血清标本40份。结果:朗道质控物和新鲜血清标本TCH、TG、APOA1、APOB、HDL-C、LDL-C浓度在系统间的差异均有显著性(P<0.05)。除LDL-C在各检测系统间的相关系数为0.7859~0.9259之间外,其他项目各系统间的相关系数均大于0.975。各检测系统测定TCH、TG的不精密度CV均小于5%,其他项目的不精密度CV均小于10%;以可溯源检测系统1为目标检测系统,临床可接受性能评价:TCH、LDL-C在检测系统2和检测系统3超出临床接受范围,HDL-C在检测系统2超出临床接受范围,其他项目临床均可接受。结论:3个不同检测系统测定TG、APOA1、APOB结果具有可比性;测定HDL-C结果具有部分可比性,TCH、LDL-C结果不具有可比性,需采取整改措施。 相似文献
59.
Suck G Branch DR Aravena P Mathieson M Helke S Keating A 《International immunology》2006,18(9):1347-1354
The major mechanism for NK cell lysis of tumor cells is granule-mediated cytotoxicity. Polarization of granules is a prelude to the release of their cytotoxic contents in response to target-cell binding. We describe the novel observation of constitutive granule polarization in the cytotoxic NK cell line, KHYG-1. Continuous degranulation of KHYG-1 cells, however, does not occur and still requires target-cell contact. Disruption of microtubules with colcemid is sufficient to disperse the granules in KHYG-1 and significantly decreases cytotoxicity. A similar effect is not obtained by inhibiting extracellular signal-related kinase 2 (ERK2), the most distal kinase investigated in the cytolytic pathway. Disruption of microtubules significantly down-regulates activation receptors, NKp44 and NKG2D, implicating them as potential microtubule-trafficking receptors. Such changes in upstream receptor expression may have caused deactivation of ERK2, since NKG2D cross-linking also leads to receptor down-regulation and diminished ERK phosphorylation. Thus, a functional role for NKG2D in KHYG-1 cytotoxicity is demonstrated. Moreover, the novel primed state may contribute to the high cytotoxicity exhibited by KHYG-1. 相似文献
60.
We wanted to evaluate whether testing for anti-phosholipid antibodies other than anti-cardiolipin (aCL) and anti-beta-2 glycoprotein I (abeta2GPI) immunoglobulin (Ig)G and IgM identifies patients with recurrent pregnancy loss (RPL) who may be positive for anti-phospholipid syndrome (APS). In a cross-sectional study comprising 62 patients with APS, 66 women with RPL, 50 healthy blood donors and 24 women with a history of successful pregnancies, we tested IgM and IgG antibodies to phosphatidic acid, phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl glycerol, phosphatidyl inositol and phosphatidyl serine with and without beta-2 glycoprotein I (beta2GPI) from a single manufacturer as well as aCL and abeta2GPI antibodies. Diagnostic accuracies of individual and combined anti-phospholipid (aPL) assays were assessed by computing sensitivities, specificities, positive predictive values and negative predictive values together with their 95% confidence intervals. There was a general trend for increased sensitivities in the presence of beta2GPI co-factor with significant effect for certain specificities. The overall combined sensitivity of the non-recommended aPL assays was not significantly higher than that of the aCL and aB2GPI tests. Multiple aPL specificities in RPL group is not significantly different from controls and therefore of no clinical significance. 相似文献