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91.
If you do a search for the word balance on a popular bookseller's Web site, you will find more than 3200 titles incorporating it, everything from balancing power to balancing your diet. Clearly we have great deal of interest in achieving it. But I will venture a guess that most of us who strive for balance in our personal lives or organizations are unable to achieve it, let alone sustain it, because we have outgrown the word entirely.The Latin definition of balance means “a pair of scales.” When we strive to equal out this or that, we limit our options for surviving and thriving in a chaotic world. Our lives are colored with uncertainty and complexity. 相似文献
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Jody Sharp Toni Azar David Lawson 《Contemporary topics in laboratory animal science》2005,44(2):32-40
To determine whether a nonsocial enrichment program affects cardiovascular responses of individually housed male Sprague-Dawley (SD) and spontaneously hypertensive (SH) rats under basal conditions and after potentially stressful procedures, we used radiotelemetry to record heart rate (HR), systolic blood pressure (SBP), and activity in the cage. Enrichment comprised a simulated burrow (Rodent Retreat), then a food foraging item ("rat cannoli") 2 days later, and a paper bag of bedding for shredding (Nestpak) after another 2 days. Data were collected under undisturbed conditions and before and after several acute and chronic manipulations mimicking common husbandry, experimental, and stressful procedures. Enrichment often, but not always, reduced HR and SBP in male rats, suggesting decreased arousal and stress, and the effects depended on the parameter measured, strain of rat, and nature of the procedure to which animals were exposed. In general, HR varied more than SBP; enrichment affected SH rats more than SD rats; effects of enrichment were more consistently observed under undisturbed conditions than after manipulations of the rats; moderate responses to acute husbandry and experimental procedures were affected more than the larger changes produced by very stressful procedures; and responses to social interactions were unaffected by the enrichment program. What accounts for these variable effects of enrichment is unclear, and more studies are required to resolve the mechanisms. Whether this enrichment program should be used in an animal facility depends on several factors, particularly the professional judgment of the research, veterinary, and animal care staffs involved. 相似文献
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目的:缝隙连接蛋白43对维持心肌细胞的连接通讯功能、电信号传导和正常的节律性收缩起重要作用,其表达和分布的异常是多种室性心律失常的解剖学基础,建立小型猪急性心肌梗死模型.观察自体骨髓间充质干细胞移植后室性心动过速的发生及心肌缝隙连接蛋白43的表达方法:实验于2006-01/2007-01在河北省人民医院导管室完成。①材料:选取8~12月龄小型猪22头,由河北医科大学实验动物中心提供,体质量20~30 kg,随机数字表法分为细胞移植组12头、模型对照组10头.实验过程中对动物的处置符合动物伦理学际准②实验方法:无菌条件下抽取猪双侧股骨骨髓20 mL,percoll法 贴壁法分离培养骨髓间充质干细胞,待细胞生长达75%融合时用胰酶消化传代。将传至第2代细胞加入终浓度为10μmol/L的5-氮胞苷进行诱导,用胶体金标记12 h后继续培养20 d用于移植:两组小型猪均采用球囊堵闭法建立急性心肌梗死模型.心电图监测示相关至少2个导联ST段抬高大于0.2 mV、术后血肌钙蛋白和肌酸磷酸激酶同工酶升高超过正常的两倍为建模成功标准:细胞移植组于造模成功后经OTW球囊于第一对角支远端1 cm处再次阻断血流,注入经胶体金标记的10×10~7个骨髓间充质干细胞。③实验评估:于细胞移植后2 h及4周行电生理程序刺激.观察室性心动过速的发生情况。末次电生理检查后、采用免疫组化染色法检测心肌缝隙连接蛋白43的表达.计算其积分吸光度值。结果:①模型建立指标检测:与术前比较.造模后所有小型猪血肌钙蛋白含量和肌酸磷酸激酶同工酶活性均增高,峰值浓度分别为(21.3±3.6)μg/L和(178.3×41.4)IU/L,术中心电图ST段平均抬高(10.67±1.43)mm.证明急性心肌梗死模型成功建立。②骨髓间充质干细胞移植后室性心动过速的发生情况:与模型对照组诱发出室性心动过速的动物数量比较,术后2 h细胞移植组无明显变化(X~2=0.201,P=0.650),术后4周细胞移植组明显降低(X~2=4.455.P=0.035)。②骨髓间充质干细胞移植后梗死心肌缝隙连接蛋白43的表达:术后4周移植到梗死心肌的骨髓间充质干细胞与宿主心肌生长为一体,移植部位颜色变黑,苏木精-伊红染色示移植细胞的胞浆呈紫红色。细胞移植组心肌梗死区缝隙连接蛋白43积分吸光度值明显高于模型对照组(t=16,82.P=0.00),细胞移植组中未发生室性心动过速小型猪的梗死心肌缝隙连接蛋白43的表达明显高于发生室性心动过速小型猪(t=5.06,P=0.00)。结论:自体骨髓间充质干细胞移植可促进急性心肌梗死猪心肌缝隙连接蛋白43的表达,其表达程度可能与急性心肌梗死室性心动过速的发生有关。 相似文献
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Antigen-specific T-cell factor in cell cooperation: physical properties and mapping in the left-hand (K) half of H-2 总被引:7,自引:14,他引:7 下载免费PDF全文
A J Munro M J Taussig R Campbell H Williams Y Lawson 《The Journal of experimental medicine》1974,140(6):1579-1587
Mouse thymus cells, educated to poly(tyrosyl,glutamyl)-polyDLalanyl--polylysyl [(T,G)-A--L], release an antigen-specific factor on brief culture in vitro. The factor cooperates with bone marrow cells in the antibody response to (T,G)-A--L in irradiated recipients. Its mol wt determined from Sephadex G100 chromatography is in the region of 50,000. The factor is removed by specific antigen-coated columns, but not by anti-immunoglobulin (anti-Fab, anti-µ, anti-Fv) adsorbents. The factor is removed by alloantisera directed against the H-2 haplotype of the strain in which it is produced. Moreover, only antisera with specificity for the K side of H-2 were successful in removing the factor activity. 相似文献
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Sung‐Hee Shin Brian Claggett Marc A. Pfeffer Hicham Skali Jiankang Liu David Aguilar Rafael Diaz Kenneth Dickstein Hertzel C. Gerstein Lars V. Kber Francesca C. Lawson Eldrin F. Lewis Aldo P. Maggioni John J.V. McMurray Jeffrey L. Probstfield Matthew C. Riddle Jean‐Claude Tardif Scott D. Solomon 《European journal of heart failure》2020,22(7):1133-1143
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Alves Pereira Ivanio Maldonado Cocco José Feijó Azevedo Valderillo Guerra Generoso Bautista-Molano Wilson Casasola Julio César Vega Morales David Soriano Enrique Roberto Gil Diana Rocío Zazzetti Federico Aldunate Leandro Holdsworth Elizabeth Anita Massey Olivia Lobosco Steve Lawson Fabio 《Clinical rheumatology》2020,39(6):1813-1822
Clinical Rheumatology - Discordance (misalignment) regarding treatment satisfaction may exist in real-life clinical practice between patients and their physicians. We aimed to assess physician and... 相似文献
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