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Steffen Dietzel Anna Jauch Dirk Kienle Guoquiong Qu Heidi Holtgreve-Grez Roland Eils Christian Munkel Michael Bittner Paul S. Meltzer Jeffrey M. Trent Thomas Cremer 《Chromosome research》1998,6(1):25-33
Fluorescence in situ hybridization (FISH) with microdissection probes from human chromosomes 3 and 6 was applied to visualize arm and subregional band domains in human amniotic fluid cell nuclei. Confocal laser scanning microscopy and quantitative three-dimensional image analysis showed a pronounced variability of p- and q-arm domain arrangements and shapes. Apparent intermingling of neighbouring arm domains was limited to the domain surface. Three-dimensional distance measurements with pter and qter probes supported a high variability of chromosome territory folding. 相似文献
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The large-scale structure of chromatin corresponding to G- and R-bands in human G0/G1 interphase nuclei was compared. Fluorescence in situ hybridization (FISH) was used to measure the interphase distance between 42 pairs of probes separated by 0.1–1.5Mbp. The probe pairs were derived from 21q22.2 and Xp21.3, G-band positive regions, and from 4p16.3, 6p21.3, and Xq28, R-band positive regions. Distributions of measured interphase distances in all regions approximated a Rayleigh distribution, suggesting that the chromatin follows a random-walk path over this range. A linear correlation of mean-square interphase distance and genomic separation, also indicative of random-walk folding, was observed in all regions. The slope of the correlation observed using probes from G-band regions was systematically lower than that from R-band regions. The difference in the slope between Xp21.3 and Xq28 was particularly striking and was observed in normal fibroblast cells, fixed alternatively with methanol and acetic acid or paraformaldehyde, and HeLa cells. These results demonstrate regional differences in large-scale chromosome structure during interphase, with the more openly configured chromatin corresponding to R-bands.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
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土鳖虫水提物对实验性高脂血症大鼠血管内皮和内皮素的影响 总被引:19,自引:0,他引:19
目的研究土鳖虫水提物对高脂血症大鼠血管内皮和内皮素 (ET)的影响。方法建立高脂血症大鼠模型 ,测定血浆ET的浓度 ,并应用内皮细胞铺片和免疫组化相结合的方法 ,在大鼠主动脉内皮细胞铺片上 ,计数内皮细胞和ET阳性细胞并定量分析ET的合成。结果实验第 80d ,与正常组比较 ,高脂组血浆ET显著增高 (P <0 .0 1) ;内皮铺片显示内皮细胞数量增多 ,排列紊乱 ,胞核大小和染色深浅不一 ,ET阳性细胞率显著升高 (P <0 .0 1)。土鳖虫中、高剂量组血浆ET水平和ET阳性细胞率显著降低 (P <0 .0 5~ 0 .0 1)。结论土鳖虫水提物能保护血管内皮 ,减少ET的合成与释放 相似文献
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Anton V. Barsukov Alexander E. Korovin Leonid P. Churilov Ekaterina V. Borisova Dmitry V. Tovpeko 《Pathophysiology》2022,29(3):453
Low-intensity systemic inflammation is an important element of heart failure pathogenesis. The aim of this study is to assess proinflammatory status serum indicators (C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6)) in middle-aged males (M) and females (F) with essential hypertension (HTN) depending on left ventricular (LV) diastolic dysfunction (LVDD). The main group comprised 55 M and 49 F with the first- to second-severity grade HTN with mild heart failure and a preserved LV ejection fraction ≥50%. Patients had sinus rhythm, first or second-severity degree LVDD, LV hypertrophy, left atrium dilatation, and NT-proBNP > 125 pg/mL. Comparison group: 30 hypertensives without cardiac dysfunction; control group: 31 normotensives. Quantitative features were compared using the Mann–Whitney test, median χ2, ANOVA module. Spearman’s rank correlation coefficients were determined to identify the relationship between the proinflammatory pattern and exercise tolerance. Hypertensive M had markedly higher CRP, TNF-α, and IL-6 levels compared to F. All mean values corresponded to reference range. In patients with second-degree LVDD, CRP, TNF-α, and IL-6 levels were significantly greater than in subjects with first-degree LVDD (both within M and within F samples). Significant negative associations between CRP, IL-6, and TNF-α levels and the 6 min walk test existed in hypertensive M and F. The study demonstrated a close relationship between the proinflammatory pattern and LVDD and exercise tolerance indicators, regardless of the hypertensive patient’s sex. 相似文献
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Hirotsugu Ohkubo Kohei Fujita Akiko Nakano Yuki Amakusa Yuta Mori Kensuke Fukumitsu Satoshi Fukuda Yoshihiro Kanemitsu Takehiro Uemura Tomoko Tajiri Ken Maeno Yutaka Ito Tetsuya Oguri Yoshiyuki Ozawa Takayuki Murase Akio Niimi 《Journal of thoracic disease》2022,14(11):4309
BackgroundThe strength, assistance in walking, rising from a chair, climbing stairs, and falls questionnaire (SARC-F) is widely used for screening sarcopenia. We aimed to examine the association of SARC-F scores with the measurements of quality of life and activity in patients with idiopathic pulmonary fibrosis (IPF).MethodsThis cross-sectional pilot study prospectively enrolled 54 patients with IPF who completed pulmonary function tests, the 6-min walk test, the chronic obstructive pulmonary disease assessment test (CAT), St. George’s Respiratory Questionnaire (SGRQ), the Hospital Anxiety and Depression Scale, and a daily step count. The daily step count was measured continuously for 7 consecutive days using a tri-axis accelerometer device.ResultsThe mean age was 73.6±7.9 years and the mean percent predicted forced vital capacity was 80.4%±15.6%. The median [interquartile range] SARC-F score, SGRQ total scores, and CAT scores were 2 [1–3.25], 28.8 [14.4–46.9], and 13 [7–22], respectively. SARC-F scores were correlated with the percent predicted forced vital capacity (r=−0.51, P<0.001), CAT score (r=0.57, P<0.001), SGRQ total score (r=0.77, P<0.001), Hospital Anxiety and Depression Scale anxiety score (r=0.31, P=0.025), and Hospital Anxiety and Depression Scale depression score (r=0.28, P=0.041). Linear regression analyses revealed that the 6-minute walk test (6MWT) (standardized β=0.33, P=0.011) and SARC-F score (standardized β=−0.39, P=0.005), but not the CAT score and SGRQ total score, were significant predictors for daily step count.ConclusionsSARC-F scores were correlated with health status and daily activity in patients with IPF. Further studies are warranted to validate the utility of the SARC-F in patients with IPF. 相似文献
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目的:检验3米后向步行试验(3MBWT)在脑卒中患者动态平衡功能评估中的信效度和反应性。方法:选取2020年12月至2021年6月温州医科大学附属第二医院40例脑卒中患者,完成3MBWT、Berg平衡量表(BBS)、“计时-起立-行走”测试(TUGT)和改良版Barthel指数(MBI)后进行Spearman相关分析。两位护理人员分别测试同一患者的3MBWT,2 h后其中1名研究人员重新测试该患者的3MBWT,计算组内相关系数(ICC)。治疗1周后,40例患者再次测试3MBWT、BBS和TUGT,比较3种工具对治疗前后效果的反应性。结果:3MBWT重测信度检验显示ICC值为0.889,评定者间信度ICC值为0.998;3MBWT与BBS(r=-0.854,P<0.001)、TUGT(r=0.872,P<0.001)强相关,3MBWT与MBI中度相关(r=-0.519,P<0.001);|ES|和|ERM|值排序依次为3MBWT>TUGT>BBS。结论:3MBWT在评价卒中患者动态平衡功能中具备良好的信度、效度和反应性。 相似文献
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《Gait & posture》2019
BackgroundThe six-minute walk test (6MWT) is used within clinical and research settings to assess gait performance across a variety of conditions and populations. Commonly, the test is used to identify specific aspects of gait that affect functional mobility. With the advancement of new technologies such as wireless inertial sensors, it has become possible to collect reliable, sensitive, and objective measures of gait. While the 6MWT has been accepted and used for many years, a more concise, while still objective gait analysis would likely benefit clinicians, researchers and patients.Research QuestionDoes a concise 2-minute walk test (2MWT) provide similar information regarding gait performance and gait differences as the 6MWT in healthy young (YA) and older adults (OA)?MethodsA total of thirty-one participants (sixteen young adults and fifteen older adults) conducted a continuous 6MWT at their self-selected pace. All participants wore six wireless inertial sensors which were placed on each foot, at the lumbar, sternum, and on each wrist. Once completed the 6MWT data was spliced into three, distinct two-minute segments. Spliced data was analyzed and compared between groups and segments.ResultsResults demonstrate significant age-related differences in several gait metrics, primarily with older adults showing increased spatiotemporal variability. Additionally, no significant differences were observed between the three, two-minute segments and the continuous 6MWT, with the exception of total number of strides completed.SignificanceThese results demonstrate that the 2MWT may provide a preferable alternative to assessing gait performance by reducing confounds such as fatigue while maintaining sensitivity of measuring gait performance. These improvements may be particularly beneficial when studying populations of advanced age or with neurological disorder. 相似文献
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《European journal of surgical oncology》2021,47(11):2830-2840
IntroductionFrail patients with colorectal cancer (CRC) are at increased risk of complications after surgery. Prehabilitation seems promising to improve this outcome and therefore we evaluated the effect of physical prehabilitation on postoperative complications in a retrospective cohort of frail CRC patients.MethodsThe study consisted of all consecutive non-metastatic CRC patients ≥70 years who had elective surgery from 2014 to 2019 in a teaching hospital in the Netherlands, where a physical prehabilitation program was implemented from 2014 on. We performed both an intention-to-treat and per protocol analysis to evaluate postoperative complications in the physical prehabilitation (PhP) and non-prehabilitation (NP) group.ResultsEventually, 334 elective patients were included. The 124 (37.1%) patients in the PhP-group presented with higher age, higher comorbidity scores and walking-aid use compared to the NP-group. Medical complications occurred in 26.6% of the PhP-group and in 20.5% of the NP-group (p = 0.20) and surgical complications in 19.4% and 14.3% (p = 0.22) respectively. In all frailty subgroups, the medical complications were lower in the PhP-group compared to the NP-group (35.9% vs. 45.5% for patients with ≥2 comorbidities, 36.2% vs. 39.1% for ASA score ≥ III, 29.2% vs. 45.8% for walking-aid use). Differences were not significant.ConclusionsIn this study, patients selected for physical prehabilitation had a worse frailty profile and therefore a higher a priori risk of postoperative complications. However, the postoperative complication rate was not increased compared to patients who were less frail at baseline and without prehabilitation. Hence, physical prehabilitation may prevent postoperative complications in frail CRC patients ≥70 years. 相似文献