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91.
David C. Cone MD Susan M. Nedza MD MBA James J. Augustine MD Steven J. Davidson MD MBA 《Academic emergency medicine》2002,9(11):1085-1090
This paper reports the proceedings of the discussion panel assigned to look at clinical aspects of quality in emergency medicine. One of the seven stated objectives of the Academic Emergency Medicine consensus conference on quality in emergency medicine was to educate emergency physicians regarding quality measures and quality improvement as essential aspects of the practice of emergency medicine. Another topic of interest was a discussion of the value of information technology in facilitating quality care in the clinical practice of emergency medicine. It is important to note that this is not intended to be a comprehensive review of this extensive topic, but instead is designed to report the discussion that occurred at this session of the consensus conference. 相似文献
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94.
Xiaoguang Chen Yi Li Lei Wang Mark Katakowski Lijie Zhang Jieli Chen Yongxian Xu Subhash C. Gautam Michael Chopp 《Neuropathology》2002,22(4):275-279
Intravenous administration of human bone marrow stromal cells (hMSCs) after middle cerebral artery occlusion (MCAo) in rats provides functional benefit. We tested the hypothesis that these functional benefits are derived in part from hMSC production of growth and trophic factors. Quantitative sandwich enzyme‐linked immunosorbent assay (ELISA) of hMSCs cultured with normal and MCAo brain extracts were performed. hMSCs cultured in supernatant derived from ischemic brain extracts increased production of brain‐derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). These neurotrophins and angiogenic growth factors increased in a post‐ischemia time‐dependent manner. The hMSC capacity to increase expression of growth and trophic factors may be the key to the benefit provided by transplanted hMSCs in the ischemic brain. 相似文献
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Michael C. Dalsing MD Melissa Kevorkian BS Beth Raper BA Craig Nixon MS Stephen G. Lalka MD Dolores F. Cikrit MD Joseph L. Unthank PhD Malcolm B. Herring MD 《Annals of vascular surgery》1989,3(2):127-133
This study evaluates the potential for endothelial seeding of a collagen-impregnated Dacron graft with or without surface modifiers (fibronectin, heparin) to attach and retain these cells during flow. Human umbilical endothelial cells were harvested, cultured, labeled with Indium111-oxine and seeded onto 30 mm X 4 mm diameter grafts. Six graft surfaces were studied: 1) a collagen-impregnated Dacron graft, HemashieldR (C); 2) C + fibronectin (C + F); 3) C + heparin (C + H); 4) C + F + H; 5) HytrelR + F (Hyt + F); and 6) Hyt + F + H. Radioactive loss determined the percentage attachment and then percentage retention of labeled inoculum after a one-hour in vitro perfusion. Scanning electron and light microscopy demonstrated the endothelium on the graft surface following perfusion. Fibronectin-coated grafts had a significantly higher percentage attachment than those without fibronectin (ANOVA, P less than 0.05). However, the percentage retention following perfusion was similar for all Dacron grafts and statistically inferior to the HytrelR grafts studied (ANOVA, P less than 0.05). SEM evaluation of the C + F + H graft surface was qualitatively the most impressive Dacron surface for seeding, yet was inferior to the HytrelR graft. We conclude that fibronectin benefits the initial attachment of endothelium to collagen-coated Dacron rivaling the HytrelR surface. Fibronectin does not improve percentage retention of the HemashieldR surface during perfusion, therefore, some of its initial benefit is lost. 相似文献
97.
Infantile Digital Fibroma Treated With Mohs Micrographic Surgery 总被引:2,自引:0,他引:2
John G. Albertini MD Maj USAF MC Michael Jude Welsch MD CPT USA MC Leo A. Conger MD LTC USA MC Lester F. Libow MD COL USA MC Dirk M. Elston MD COL USA MC 《Dermatologic surgery》2002,28(10):959-961
BACKGROUND: Infantile digital fibroma (IDF) is a rare benign fibrous tumor of childhood that frequently recurs despite local excision. Conservative, nonsurgical management may result in regression and/or joint deformity. OBJECTIVE: To describe the histologic features of IDF and discuss a case excised using Mohs micrographic surgery (MMS). METHODS: Case report and review of the clinical, histologic, and ultrastructural features. RESULTS: Characteristic inclusion bodies of actin were identified with hematoxylin and eosin, Masson's trichrome, and rapid actin immunostain. The tumor was debulked and the majority was removed after one stage of MMS, except where the deep margin approached the joint space. The defect healed by secondary intention. At 2 years the patient had no recurrence or functional joint deformity. CONCLUSION: MMS is a surgical treatment option for IDF. 相似文献
98.
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
99.
成人成骨细胞与珊瑚羟基磷灰石的体外生物相容性 总被引:13,自引:2,他引:11
目的:研究成人骨髓成骨细胞与珊瑚羟基磷灰石(carolline hydroxyapatite,CHA)在体外培养条件下的生物相容性。方法:抽取健康成人骨髓组织,置于含体积分数为10%胎牛血清的DMEM培养基中培养,传代后改用含地塞米松、β-甘油磷酸钠和维生素C的条件培养基培养,分为CHA复合细胞组和单纯细胞组,不同时间用倒置相关显微镜,HE染色光镜及扫描电镜观察,MTT法进行细胞增殖测定,并进行细胞微量蛋白含量和碱性磷酸酶的定量检测,结果:成人骨髓成骨细胞体外培养时复合或不复合CHA均生长良好,表现出典型成骨细胞的形态特征和生物学特性,CHA利于细胞的贴附,生长与增殖,并对细胞的功能无不良影响,结论:CHA是较理想的骨组织工程支架材料,成骨细胞复合CHA用于骨缺损的修复,具有广阔的临床应用前景。 相似文献
100.