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51.
John S. Preisser Gary G. Koch William W. Shockley 《Journal of biopharmaceutical statistics》2013,23(2):167-183
Complementary statistical analyses are performed on data concerning tracheal reconstruction in rats. The principal response criterion is vessel area as defined by the area of a graft onto the trachea covered by blood vessels. Postoperatively, this vessel area changes in a nonlinear fashion over time. Starting at 0% immediately postoperation, the vessel area increases to a peak and then sharply decreases to a certain level at which it remains. A total of 64 independently observed cross-sectional pairs (postop day, vessel area) are distributed among four treated groups. Analysis consists of two-way analysis of variance and piecewise linear regression under the usual assumptions of normality and variance homogeneity. Other analyses that relax these assumptions are also considered; treatment differences are established by nonparametric tests, and a quasi-likelihood analysis of the piecewise linear regression model is applied under the assumption of a binomial-like variance function. The resulting fit of the normal-theory-based piecewise linear model is compared to that of a nonlinear model whose shape is that of a gamma function integrand. 相似文献
52.
《Injury》2016,47(12):2733-2738
IntroductionPoor bone quality and unstable fractures increase the cut-out rate in implants with gliding lag screws. The U-Blade (RC) lag screw for the Gamma3® nail was introduced to provide monoaxial rotational stability of the femoral head and neck fragment. The purpose of this study was to evaluate whether the use of the U-Blade (RC) lag screw is associated with reduced cut-out in patients with OTA/AO 31A1-3 fractures.Material & methodsBetween 2009 and 2014, 751 patients with OTA/AO 31A1-3 fractures were treated with a Gamma3® nail at our institution. Out of this sample 199 patients were treated with U-blade (RC) lag screws. A total of 135 patients (117 female, 18 male) with standard lag screw (treatment group A) were matched equally regarding age (±4 years) sex, fracture type and location to 135 patients with U-blade (RC) lag screw (treatment group B). Within a mean follow up of 9.2 months (range 6–18 months) we assessed the cut-out rate, the calTAD, lag screw migration, the Parker's mobility score and the Parker’s ratio at postoperatively, six and 12 months following surgery. Furthermore we recorded all complications, ASA-Score, hospital stay and duration of surgery retrospectively.ResultsThe most common fracture among group B with a cut-out of the lag screw were AO/OTA 2.3 and 3.2 fractures whereas in group A cut-out was most commonly seen in AO/OTA 2.1, 2.2 and 2.3 fractures, there was no significant reduction of the cut-out rate in group B 2.2% (n = 3) compared to group A 3.7% (n = 5). The duration of surgery was significantly shorter in group A (p < 0.05). There was no significant difference in lag screw placement, the Parker’s ratio and mobilization.ConclusionIn our study the U-Blade (RC) lag screw did not reduce the cut-out in treatment of OTA/AO 31A1-3 fractures at all. Considering the longer duration of surgery and the higher costs of the U-Blade (RC) lag screw, our results do not justify its use. However, further prospective randomized studies will be necessary. 相似文献
53.
Martin Zydek Matthew Petitt June Fang-Hoover Barbara Adler Lawrence M. Kauvar Lenore Pereira Takako Tabata 《Viruses》2014,6(3):1346-1364
Human cytomegalovirus (HCMV) is the major viral cause of congenital infection and birth defects. Primary maternal infection often results in virus transmission, and symptomatic babies can have permanent neurological deficiencies and deafness. Congenital infection can also lead to intrauterine growth restriction, a defect in placental transport. HCMV replicates in primary cytotrophoblasts (CTBs), the specialized cells of the placenta, and inhibits differentiation/invasion. Human trophoblast progenitor cells (TBPCs) give rise to the mature cell types of the chorionic villi, CTBs and multi-nucleated syncytiotrophoblasts (STBs). Here we report that TBPCs are fully permissive for pathogenic and attenuated HCMV strains. Studies with a mutant virus lacking a functional pentamer complex (gH/gL/pUL128-131A) showed that virion entry into TBPCs is independent of the pentamer. In addition, infection is blocked by a potent human neutralizing monoclonal antibody (mAb), TRL345, reactive with glycoprotein B (gB), but not mAbs to the pentamer proteins pUL130/pUL131A. Functional studies revealed that neutralization of infection preserved the capacity of TBPCs to differentiate and assemble into trophospheres composed of CTBs and STBs in vitro. Our results indicate that mAbs to gB protect trophoblast progenitors of the placenta and could be included in antibody treatments developed to suppress congenital infection and prevent disease. 相似文献
54.
目的 比较立体定向射频热凝术与立体定向放射技术(伽玛刀)治疗原发性三叉神经痛的疗效。方法 回顾性分析2014-01至2016-01收治的46例原发性三叉神经痛患者临床资料,其中立体定向射频热凝术21例(射频组),伽玛刀治疗25例(伽玛刀组)。对比两组治疗后疼痛控制率、并发症和复发情况,评定疗效。结果 46例随访时间12~36个月,平均25.6个月。根据巴罗(BNI)疼痛量表评定,射频组术后Ⅰ级17例(81.0%),Ⅱ级2例(9.5%),Ⅲ级1例(4.8%),Ⅳ~Ⅴ级1例(4.8%),有效Ⅰ~Ⅲ级20例(95.2%);伽玛刀组术后Ⅰ级12例(48.0%),Ⅱ级4例(16.0%),Ⅲ级6例(24.0%),Ⅳ~Ⅴ级3例(12.0%),有效Ⅰ~Ⅲ级22例(88.0%)。术后两组比较,射频组Ⅰ级优于伽玛刀治疗组,差异有统计学意义(P<0.05),Ⅱ、Ⅲ级及有效率差异无统计学意义。术后射频组面部麻木发生率(81.0%)明显高于伽玛刀组(9.5%),咀嚼肌力下降、口角流涎、角膜炎发生率等两组对比,差异无统计学意义。射频组、伽玛刀组复发各1例。结论 射频热凝和伽玛刀治疗三叉神经痛疗效肯定,射频治疗起效快,恢复优良率高,但有一定的侵袭性和并发症;伽玛刀治疗无创,并发症少且轻,相对更安全,缺点是起效较慢。 相似文献
55.
56.
This review describes a wide range of functional correlates of gamma oscillations in whole-brain work, in neuroethology, sensory–cognitive dynamics, emotion, and cognitive impairment. This survey opens a new window towards understanding the brain's gamma activity. 相似文献
57.
58.
郭志芬 《中国实用护理杂志》2012,28(19):45-47
目的 探讨大剂量静脉滴注丙种球蛋白防止川崎病患儿冠状动脉损害的效果.方法 将82例川崎病患儿依据治疗方法分为观察组和对照组各41例,观察组患儿采用大剂量丙种球蛋白冲击治疗,对照组应用常规用量进行治疗.对照组采取常规护理,观察组在对照组的基础上按症状实施针对性的护理措施.比较2组的治疗及护理效果.结果 观察组发生冠状动脉扩张1例,对照组发生8例,观察组发生率显著低于对照组.主要观察指标如发热、淋巴结肿大及皮肤黏膜改变的恢复时间观察组明显较对照组缩短.结论 良好细致的护理和健康教育指导,可增加患儿及家属对川崎病的了解,积极配合医疗各个环节,可减少并发症,加快疾病康复. 相似文献
59.
Sodium copper chlorophyllin (SCC) has a genetic damage inhibitory capacity due to its antioxidant action. For this reason, it was considered to investigate its role in the life span of Drosophila melanogaster and its relationship with the frequency of somatic mutation induced by gamma rays. Results indicated that SCC alone prolonged the lifespan only in females, but in combination with 20 Gy of gamma rays, the aging delay in both sexes was significant. In addition to confirming that the porphyrin reduces the frequency of mutation, the individuals with the highest mutation load are the individuals who die more quickly, and once they are eliminated, the survivor individuals treated with 20 Gy or with SCC + 20 Gy, died at the same rate. The results together indicate that SCC not only inhibits induced genetic damage, but it also has beneficial effects that probably cause an aging delay of the treated population that need to be investigated. 相似文献
60.
《Archivos de bronconeumologia》2014,50(11):484-489
This article analyzes the concept of inactive fibrotic lesions of presumed tuberculous origin (old healed tuberculosis), defined by radiological characteristics and a positive tuberculin skin test (TST), and we examine the evidence-based foundation for the indication of treatment of latent tuberculosis infection in these cases. We explore the risk of reactivation in older and recent literature, and the problems raised by the differential diagnosis with active tuberculosis with negative bacteriology. We also analyze data on the prevalence of fibrotic lesions in the recent literature. We examine the possible role of Interferon Gamma Release Assays (IGRAs) versus TST and other molecular antigen detection techniques in sputum that can aid in establishing the diagnosis and we discuss the current indications for chemoprophylaxis and the different options available. We propose diagnostic guidelines and therapeutic algorithms based on risk stratification by age and other factors in the management of radiological lesions that raise a differential diagnosis between fibrotic lesions and active pulmonary tuberculosis with negative bacteriology. 相似文献