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81.
导管室介入封堵及外科小切口介入封堵都已经被广泛地应用于临床,封堵成功的关键在于经胸与经食管超声心动图在术前对病例精确的筛选、术中监测及术后即刻评价。文章结合目前国内外文献及临床病例,对经胸与经食管超声心动图在房间隔缺损、室间隔缺损和动脉导管未闭3种常见先天性心脏病介入治疗中的应用进行综述,为临床提供更加准确的超声影像学诊断依据。 相似文献
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Decreased Mechanical Strength and Collagen Content in SPARC‐Null Periodontal Ligament Is Reversed by Inhibition of Transglutaminase Activity
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Jessica Trombetta‐eSilva Emilie A Rosset R Glenn Hepfer Gregory J Wright Catalin Baicu Hai Yao Amy D Bradshaw 《Journal of bone and mineral research》2015,30(10):1914-1924
The periodontal ligament (PDL) is a critical tissue that provides a physical link between the mineralized outer layer of the tooth and the alveolar bone. The PDL is composed primarily of nonmineralized fibrillar collagens. Expression of secreted protein acidic and rich in cysteine (SPARC/osteonectin), a collagen‐binding matricellular protein, has been shown to be essential for collagen homeostasis in PDL. In the absence of SPARC, PDL collagen fibers are smaller and less dense than fibers that constitute WT PDL. The aim of this study was to identify cellular mechanisms by which SPARC affected collagen fiber assembly and morphology in PDL. Cross‐linking of fibrillar collagens is one parameter that is known to affect insoluble collagen incorporation and fiber morphology. Herein, the reduction in collagen fiber size and quantity in the absence of SPARC expression was shown to result in a PDL with reduced molar extraction force in comparison to that of WT mice (C57Bl/6J). Furthermore, an increase in transglutaminase activity was found in SPARC‐null PDL by biochemical analyses that was supported by immunohistochemical results. Specifically, collagen I was identified as a substrate for transglutaminase in PDL and transglutaminase activity on collagen I was found to be greater in SPARC‐null tissues in comparison to WT. Strikingly, inhibition of transglutaminase activity in SPARC‐null PDL resulted in increases in both collagen fiber thickness and in collagen content, whereas transglutaminase inhibitors injected into WT mice resulted in increases in collagen fiber thickness only. Furthermore, PDL treated with transglutaminase inhibitors exhibited increases in molar extraction force in WT and in SPARC‐null mice. Thus, SPARC is proposed to act as a critical regulator of transglutaminase activity on collagen I with implications for mechanical strength of tissues. © 2015 American Society for Bone and Mineral Research 相似文献
83.
目的探讨肠球菌属细菌分布及耐药性特征,为指导临床合理用药及控制医院感染提供依据。方法对该院2011年1月至2013年12月年临床送检标本进行细菌分离培养、鉴定和药敏试验。结果共检出肠球菌属细菌140株,屎肠球菌71株(50.7%),粪肠球菌60株(42.9%),其他肠球菌9株(6.4%),其中尿液99株(70.7%);粪肠球菌对青霉素、氨苄西林、红霉素的耐药率为15.0%、12.5%和75.0%,屎肠球菌对青霉素、氨苄西林、左氧氟沙星、环丙沙星、红霉素耐药率大于80.0%,粪肠球菌和屎肠球菌对万古霉素(5.0%、4.2%)、利奈唑胺(8.4%、1.4%)极度敏感,喹奴普丁/达福普丁对粪肠球菌耐药率(100.0%)高于屎肠球菌(26.7%),达托霉素无耐药菌株。结论肠球菌属以泌尿系统感染为主,屎肠球菌检出率略大于粪肠球菌,屎肠球菌对大多数抗菌药物耐药率高于粪肠球菌,喹奴普丁/达福普丁仅对屎肠球菌有较高敏感性,万古霉素、利奈唑胺、达托霉素对肠球菌属细菌保持极高敏感性。 相似文献
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BONNIE J. BAKER M.D. † MICHAEL A. BRODSKY M.D. HA DINH M.D. † BYRON J. ALLEN M.D. BARBARA COTTER L.P.N. † CATHY LUCKETT R.N. MARVIN L. MURPHY M.D. † 《Journal of cardiovascular electrophysiology》1987,1(6):527-535
The effects of propafenone on left ventricular function and hemodynamics are presented in this study. In one group of 13 patients who underwent electrophysiological testing and subsequent chronic oral therapy with propafenone, eight had left ventricular ejection fractions determined by nuclear study before and during therapy with the drug. Initial measurements ranged from 22% to 39% (mean 30%), while those on chronic therapy showed no statistical difference and ranged from 22% to 48% (mean 30%). In a separate dose titration study of 14 patients, left ventricular ejection fraction showed a modest but significant decrease (52%± 9% to 48%± 11%; p < 0.05). This change was more marked in patients with an initial low ejection fraction. Propafenone appears to be safe in these patients but should be administered with caution in patients with particularly low ejection fractions. 相似文献
88.
Early changes in protein synthesis induced by basic fibroblast growth factor, nerve growth factor, and epidermal growth factor in PC12 pheochromocytoma cells.
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H Hondermarck C S McLaughlin S D Patterson R A Bradshaw 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(20):9377-9381
Nerve growth factor (NGF) and basic fibroblast growth factor (bFGF) stimulate neuronal differentiation, whereas epidermal growth factor (EGF) promotes only mitogenic responses in PC12 pheochromocytoma cells. The early changes in protein synthesis induced by bFGF, NGF, and EGF in these cells have been determined by two-dimensional PAGE of [35S]methionine-labeled proteins and computerized image analysis. The rate of synthesis of only 29 proteins (out of approximately 1500 identified) was found to be modulated during the first several hours of growth factor stimulation. Individually, 12 were affected by EGF, 23 were affected by bFGF, and 20 were affected by NGF. Eight of these were regulated by all three growth factors, while 10 proteins were commonly induced by bFGF and NGF, in accordance with the essentially identical morphological responses induced by these two factors. In addition, the effects of bFGF and NGF were about equally divided between increases and decreases in the rate of synthesis of individual proteins, whereas EGF caused significantly more positive (increased) responses. All proteins modulated by NGF or FGF alone were negative in their response and those induced by only EGF were positive. Of particular interest, the rate of synthesis of two proteins of 55 kDa and pI 5.45 and 5.50 was dramatically and transiently induced during the first 2 hr of bFGF and NGF treatment and was not affected by EGF. This study indicates that all three factors elicit early increases and decreases in the synthesis of a quite limited number of proteins and provides molecular evidence for the specificity of a differentiative vs. a proliferative growth factor-induced signaling pathway in these cells. 相似文献
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