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31.
Eric Paul Shaber 《International journal of oral and maxillofacial surgery》1987,16(6):678-681
Recent advances in the field of biomatrix porous implant technology has stirred the interest of the oral and maxillofacial surgical community. One such material (Medpor), is a biocompatible, large-pore, high-density polyethylene implant which has proven both experimentally and clinically to fulfil the criterion for maxillofacial reconstructive and aesthetic surgical grafting. 相似文献
32.
Mo Weijtens Anke van Spronsen Anton Hagenbeek Eric Braakman Anton Martens 《Human gene therapy》2002,13(2):187-198
Graft-versus-host disease (GvHD), a major complication of allogeneic bone marrow transplantation, has been ascribed to mature T cells in the graft. Because T cells play an important role in engraftment of the bone marrow and decrease the probability of relapse of leukemia, a treatment strategy was developed to preserve the benefits of T cells in the graft and to control the severe complications of GvHD. This can be accomplished by the genetic modification of donor T cells with a suicide gene that allows their selective in vivo elimination and subsequently the abrogation of GvHD. For clinical benefit the alloreactivity of herpes simplex virus thymidine kinase (HSV-TK) gene-transduced T cells should be retained. Therefore, we investigated the influence of gene transduction and the selection procedure on T cells. We demonstrated that activation and culturing of T cells reduce their capacity to induce lethal GvHD in an allogeneic rat bone marrow transplantation model. Furthermore, positive immunomagnetic selection of gene-transduced T cells resulted in loss of the GvHD-inducing capacity of HSV-TK(+) T cells directly after MACS (magnetic cell sorting) selection; this loss could be recovered by a 1-day expansion of the selected T cells. No effect on alloreactivity was observed to be caused by the gene transduction procedure. Our study resulted in the development of an optimized culture and gene transduction protocol with preservation of T cell alloreactivity. Treatment of transplanted rats with ganciclovir resulted in a rapid reduction in the number of HSV-TK(+) T cells in the peripheral blood and in increased survival of the animals. 相似文献
33.
Kenneth K. H. Chao BS Eric Cheung BS William B. Armstrong MD Brian J. F. Wong MD 《Otolaryngology--head and neck surgery》2002,126(6):593
Objective: The study goal was to compare the laser spot size created using reflective and refractive micromanipulators with a CO2 laser and to determine the sensitivity of spot size to laser power. Study Design and Setting: A CO2 laser and operating microscope (400-mm focal length) was coupled to either a reflective (Cassegrain-like) or refractive micromanipulator. Laser spot size was determined by measuring the region of ablation created by laser irradiation of wood (dry tongue depressors), exposed photographic film, and agar gel using optical micrometry. Laser power varied from 0.5 to 20 W with pulse durations of 0.1 and 0.5 second. Results: The reflective micromanipulator demonstrated overall smaller spot sizes for a given laser power and lower incremental change in spot size with increasing power. The reflective design demonstrated less sensitivity to increases in laser power. Conclusions: Micromanipulator optical design can result in significant differences in laser spot size. The reflective device used in this study demonstrated less sensitivity to increasing laser power. (Otolaryngol Head Neck Surg 2002;126:593-597.) 相似文献
34.
Eric Sanner 《Optometry》2005,76(8):473-479
35.
Eric Racine Marie-Josée Dion Christine A. C. Wijman Judy Illes Maarten G. Lansberg 《Neurocritical care》2009,11(3):345-352
Background
Advances in intensive care medicine have increased survival rates of patients with critical neurological conditions. The focus of prognostication for such patients is therefore shifting from predicting chances of survival to meaningful neurological recovery. This study assessed the variability in long-term outcome predictions among physicians and aimed to identify factors that may account for this variability. 相似文献36.
FDA’S Perspectives on Cardiovascular Devices 总被引:1,自引:0,他引:1
Eric A. Chen Sonna M. Patel-Raman Kathryn O’Callaghan Matthew G. Hillebrenner 《Journal of cardiovascular translational research》2009,2(2):143-146
The Food and Drug Administration (FDA) decision process for approving or clearing medical devices is often determined by a
review of robust clinical data and extensive preclinical testing of the device. The mission statement for the Center for Devices
and Radiological Health (CDRH) is to review the information provided by manufacturers so that it can promote and protect the
health of the public by ensuring the safety and effectiveness of medical devices deemed appropriate for human use (Food, Drug
& Cosmetic Act, §903(b)(1, 2(C)), December 31, 2004; accessed December 17, 2008 ). For high-risk devices, such as ventricular assist devices (VADs), mechanical heart valves, stents, cardiac resynchronization
therapy (CRT) devices, pacemakers, and defibrillators, the determination is based on FDA’s review of extensive preclinical
bench and animal testing followed by use of the device in a clinical trial in humans. These clinical trials allow the manufacturer
to evaluate a device in the intended use population. FDA reviews the data from the clinical trial to determine if the device
performed as predicted and the clinical benefits outweigh the risks. This article reviews the regulatory framework for different
marketing applications related to cardiovascular devices and describes the process of obtaining approval to study a cardiovascular
device in a U.S. clinical trial. 相似文献
37.
Eric Y. T. Chan Daniel K. Ng Chung-hong Chan Ka-li Kwok Pok-yu Chow Josephine M. Cheung Suk-yu Leung 《Sleep & breathing》2009,13(1):59-63
Background and objective The purpose of this study is to assess whether Chinese children with high apnea–hypopnea index (AHI) are sleepier by a modified Epworth Sleepiness Scale (ESS).
Materials and methods Records were retrospectively reviewed. We included children who were between 3 and 12 years old, admitted for overnight polysomnogram
because of suspected obstructive sleep apnea syndrome (OSAS). A modified ESS was used to assess excessive daytime sleepiness
(EDS) of the children.
Results One hundred ninety-two Chinese children were included. Children with high AHI, defined as AHI > 5.0, were sleepier than children with AHI less than or equal
to 5. After adjustment by age, gender, and obesity, children with high AHI remained significantly sleepier. Modified ESS was
significantly correlated with AHI (rho = 0.124, 95% CI = 0.004–0.281). Modified ESS score of >8 was the best cutoff point
with the sensitivity and specificity of 0.29 and 0.91, respectively. The odds ratio of children with modified ESS > 10 having
high AHI was 4.231 (95%CI = 1.248 to 14.338) and children with modified ESS > 8 had the highest odds ratio, 4.295(95%CI = 1.66
to 11.1), of having high AHI.
Conclusion
Chinese children with high AHI appear to be sleepier than children with low AHI. Children with suspected OSAS and high modified ESS,
i.e., ESS > 8, had significantly higher odds ratio of having high AHI. Increased sleepiness is a specific but not a sensitive
symptom in snoring children with high AHI. Screening for EDS in snoring children may help us identify those with high AHI
and prioritize the management of those children.
All authors worked and the study was carried out in Kwong Wah Hospital in Hong Kong. There was no conflict of interest and
no specific source of funding for the study. 相似文献
38.
Jing‐Ping Zhang Limin Zheng Jiang‐Hai Wang Karl‐Eric Magnusson Xin Liu 《Phytotherapy research : PTR》2009,23(6):844-850
Ganoderma sinensis has been used widely in Oriental countries for the prevention and treatment of various diseases including cancer. Previous studies have shown that the lipid extract from Ganoderma exhibits direct cytotoxicity against tumor cells. Here, it is reported that the lipid extract from germinating G. sinensis spores, at lower concentrations that have no direct tumoricidal activity, induce potent antitumor immune responses in human monocytes/macrophages. Upon stimulation with the lipid extract, monocytes/macrophages exhibited markedly increased production of proinflammatory cytokines and surface expression of costimulatory molecules. Conditioned medium from stimulated cells effectively suppressed the growth of tumor cells. Apparently, the lipid extract triggered macrophage activation via a mechanism different from that associated with LPS. Moreover, it was observed that the lipid extract could partially re‐establish the antitumor activity of the immunosuppressive tumor‐associated macrophages. These results indicated that in addition to its direct tumoricidal activity, the lipid extract from G. sinensis spores could exert antitumor activity by stimulating the activation of human monocytes/macrophages. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
39.
40.
A serotonin (5-HT)-mediated phosphoinositide hydrolysis response was characterized in fibroblasts cultured from rabbit choroid plexus. 5-HT elicited a maximum 8-fold increase in [3H]inositol-phosphate ([3H]IP) formation, while the partial agonists, (+)-lysergic acid diethylamide and (−)-1-(4-bromo-2,5-dimethyoxyphenyl)-2-aminopropane caused 2- and 5-fold increases, respectively. Mianserin, ketanserin, and spiperone were equipotent at blocking the 5-HT-mediated response. Thus, agonist and antagonist profiles indicate interactions with 5-HT2 receptors. 相似文献