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41.
近年来由于训练强度不断增大,高水平运动员心律失常的发生率显著增加。本文研究资料表明,男心律失常组安静时心搏量明显大于正常组(P<0.05),而运动后心搏量降低(正常组心搏量增加),说明心律失常的运动员心脏储备能力差,心脏泵血功能降低,应予慎重对待。 相似文献
42.
Effects of posture and pneumoperitoneum during anaesthesia on the indices of left ventricular filling 总被引:6,自引:0,他引:6
P. Gannedahl S. Odeberg L.-Å. Brodin A. Sollevi 《Acta anaesthesiologica Scandinavica》1996,40(2):160-166
Background. Laparoscopic surgery requires the use of pneumoperitoneum (PP). When combined with positional changes, pneumoperitoneum may cause marked circulatory alterations.
Methods. Eight anaesthetized cardiovascularly healthy patients, scheduled for laparoscopic cholecystectomy, were studied before and during pneumoperitoneum in three different postures (supine, Trendelenburg and reversed Trendelenburg), employing transesophageal echocardiography and pulmonary artery pressure monitoring.
Results. PP significantly increased end-diastolic area (EDA) and pulmonary capillary wedge pressure (PCWP) irrespective of posture. PCWP was significantly influenced by postural changes, whereas EDA was not. Further, changes in EDA and PCWP covaried during the investigation, but showed no linear correlation. Systolic function, measured as end-systolic area (ESA) and fractional area shortening (FAS), was not altered. Diastolic function, as assessed by the velocity rate of the trans-mitral flow during the early filling phase (E) and the atrial contraction (A), showed no change of the E/A ratio, whereas after the induction of PP there was a significant reduction of the E component.
Conclusions. In cardiovascularly healthy patients, the left ventricular volume is increased during pneumoperitoneum. Further, changes in invasive pressure determinations (PCWP) do not correlate linearly with changes in volume indices of left ventricular filling (EDA). 相似文献
Methods. Eight anaesthetized cardiovascularly healthy patients, scheduled for laparoscopic cholecystectomy, were studied before and during pneumoperitoneum in three different postures (supine, Trendelenburg and reversed Trendelenburg), employing transesophageal echocardiography and pulmonary artery pressure monitoring.
Results. PP significantly increased end-diastolic area (EDA) and pulmonary capillary wedge pressure (PCWP) irrespective of posture. PCWP was significantly influenced by postural changes, whereas EDA was not. Further, changes in EDA and PCWP covaried during the investigation, but showed no linear correlation. Systolic function, measured as end-systolic area (ESA) and fractional area shortening (FAS), was not altered. Diastolic function, as assessed by the velocity rate of the trans-mitral flow during the early filling phase (E) and the atrial contraction (A), showed no change of the E/A ratio, whereas after the induction of PP there was a significant reduction of the E component.
Conclusions. In cardiovascularly healthy patients, the left ventricular volume is increased during pneumoperitoneum. Further, changes in invasive pressure determinations (PCWP) do not correlate linearly with changes in volume indices of left ventricular filling (EDA). 相似文献
43.
Willem E. Corver Gert Jan Fleuren Cees J. Cornelisse 《Journal of immunological methods》2002,260(1-2):97-107
Background: High concentrations of propidium iodide (PI), in combination with fluorescein isothiocyanate (FITC) and R-phycoerythrin (RPE) used for multiparameter DNA flow cytometry (FCM), cause spectral cross-talk into the green fluorescence channel (FL1). We have evaluated the use of post-acquisition software compensation (N-Color Compensation) in order to correct this spectral cross-talk caused by PI. Method: Cell mixtures were prepared consisting of keratin 8/18 FITC labeled, keratin 8/18 RPE labeled, and unlabeled MCF-7 breast carcinoma cells. DNA was stained with PI (100 μM). Post-acquisition software compensation was applied to correct the spectral cross-talk of PI fluorescence. Secondly, the distribution of the Ki-67 (FITC) protein during the cell cycle (PI) of SiHa cervical carcinoma cells (no software compensation) was compared to the Ki-67 expression pattern of SiHa cells, simultaneously stained for keratin 8 (RPE), after applying software compensation. Finally, software compensation was used to compare the relative levels of PCNA and p53 expression in two clinical ovarian cancer ascites specimens, stained for PCNA or p53 (FITC), keratin 8/18 (RPE), and DNA (PI), with a known p53 status (positive and negative, respectively). Results: The Ki-67 cell cycle-dependent pattern of a triply stained sample (Ki-67 (FITC), keratin 8 (RPE), and DNA (PI)) is restored after software compensation and the results are comparable to the Ki-67 distribution of a sample stained solely for Ki-67 and DNA. P53 expression could only be resolved after using software compensation in the p53 positive ovarian ascites (OA) sample. Conclusions: We conclude that software compensation is a robust and reliable post-acquisition method for the correction of RPE/PI spectral cross-talk, permitting better identification of weakly expressed proteins in heterogeneous clinical tumor samples stained for multiple cellular antigens and DNA using PI. 相似文献
44.
胰岛素样生长因子-1在妇科疾病中的作用 总被引:8,自引:3,他引:5
在许多组织增生过程中,通过内分泌、旁分泌和自分泌会产生胰岛素样生长因子-1(IGF-1)。最近的研究发现,IGF-1存在于各种增生组织,如子宫内膜和卵巢组织。患有严重子宫内膜异位症时,血清中IGF-1水平较高,而子宫内膜局部的:IGF-1水平减低,这可能是导致不孕的原因,多囊性卵巢综合征(PCOS)患者卵巢局部的IGF-1活性增强,与患者肥胖、高雄激素水平等一系列临床症状有关。IGF-1在良、恶性肿瘤中也起着重要的作用,IGF-1能刺激子宫肌瘤细胞的生长。围绝经期妇女若存在高IGF-1和低IGF-1结合蛋白-3(IGFBP-3)水平,则患乳腺癌的风险增大。绝经前后女性的高IGF-1水平与宫颈癌、卵巢癌和子宫内膜癌的发病率存在相关性。 相似文献
45.
目的:探讨妊娠黄体瘤(LP)的误诊原因。方法:对1例典型LP病例进行全面病理学检查和组化及免疫组化染色,与正常卵巢黄体进行对比分析,并复习文献。结果:LP均发生于妊娠后期,临床无明显自觉症状,其病理形态学、组织学、免疫组化反应与正常卵巢黄体相似。多在剖腹产时偶然发现而误为卵巢肿瘤。结论;LP为妊娠后期卵巢黄素化细胞的结节状增生,并非真性肿瘤。妊娠期出现卵巢明显增大,应首先考虑到本病的可能性。必要时术中可作活检,以避免误切卵巢。 相似文献
46.
促甲状腺素释放激素拮抗β-内啡肽对心血管的抑制作用 总被引:2,自引:0,他引:2
本研究用兔侧脑室给药观察了促甲状腺素释放激素(TRH)对β-内啡肽心血管抑制作用的影响。结果表示,β-内啡肽(10μg,icv)能显著抑制兔心血管功能,表现为血压下降,心机收缩力指标如左室收缩压(LVSP),心室内压最大上升和下降速率(±dp/dtmax),心肌纤维收缩速度(Vce40,Vpm)和心肌收缩向量环面积(Lp)明显降低。β-内啡肽的这一作用可被TRH(50μg,icv)取消,阿片受体拮抗剂纳洛酮(NAL,50μg,icv)也可拮抗β-内啡肽的心血管抑制作用,表明,TRH与内源性阿片肽系统有密切关系,结合以前的实验结果提示TRH拮抗β-内啡肽的心血管抑制作用有可能是作用在阿片受体上的。 相似文献
47.
双水平压力调节通气与反比通气对健康及急性肺损伤犬心肺功能影响的比较研究 总被引:12,自引:2,他引:10
目的 :比较双水平压力调节 (BIPAP)通气和反比通气 (IRV)对心肺功能的影响。方法 :在两种通气模式 0、0 .5和 1.0 k Pa呼气末压 (EEP)时 ,分别测定健康犬及油酸诱发急性肺损伤犬的呼吸力学、血流动力学及血气分析各参数。结果 :无论有无急性肺损伤 ,BIPAP通气时平均气道压 (m Paw )均明显低于 IRV时(P均 <0 .0 5 )。给健康犬用 IRV通气时 ,上述 3种 EEP水平的 m Paw分别为 (0 .437± 0 .10 3) k Pa、(0 .811±0 .0 93) k Pa和 (1.36 0± 0 .119) k Pa;用 BIPAP通气时则分别降为 (0 .2 2 5± 0 .0 71) k Pa、(0 .6 11± 0 .10 5 ) k Pa和(1.10 7± 0 .0 89) k Pa。油酸诱发急性肺损伤后 ,m Paw分别由 IRV时 (0 .72 5± 0 .2 2 2 ) k Pa、(1.186± 0 .2 98) k Pa和 (1.6 0 0± 0 .10 0 ) k Pa降至 BIPAP时 (0 .35 0± 0 .12 9) k Pa、(0 .6 2 5± 0 .15 0 ) k Pa和 (1.12 5± 0 .0 96 ) k Pa;但两种通气模式中气道峰压、心排血量并无明显差异。另外 ,急性肺损伤时 ,BIPAP通气的动脉血氧分压 (Pa O2 )分别为 (9.10± 1.79) k Pa、(11.43± 1.80 ) k Pa和 (13.40± 3.2 0 ) k Pa,较 IRV时 Pa O2 (7.87± 2 .33) k Pa、(9.0 7±3.0 5 ) k Pa和 (9.71± 1.85 ) k Pa增高 (EEP 1.0 k Pa时 ,P <0 .0 5 )。结论 : 相似文献
48.
目的观察颈丛阻滞下行颈动脉内膜剥脱术的效果.方法 28名ASAⅡ~Ⅲ级患者行32例颈动脉内膜剥脱术,采用深浅丛联合阻滞,观察围术期血液动力学指标变化,分流管放置率和并发症情况.结果 麻醉后血压和心率与麻醉前相比差异有显著性(P<0.05),其它时点与麻醉前相比差异无显著性(P>0.05).颈动脉夹闭前后收缩压和心率的波动性的差异无显著性(P>0.05).围术期高血压的发生率为50.0%,低血压6.25%,心动过速28.1%,心动过缓6.25%,分流管放置率6.25%.患者满意率84.4%.无1例改用全麻,无严重围术期并发症.结论颈丛阻滞是颈动脉内膜剥脱术安全、有效的麻醉方法. 相似文献
49.
50.
以高频喷射通气结合胸壁挤压(HFJV+CWC)为通气模式,观察其对组胺致肺损伤犬呼吸循环功能的影响,并与单纯高频喷射通气(HFJV)进行比较。结果表明:与HFJV相比,HFJV+CWC时的功能残气量(FRC)、PaCO_2和PCO_2均显著降低(P<0.01),肺泡通气量(V_A)和二氧化碳排出量(CO_2)均显著增高(P<0.01),每分呼出气量(V_E)、PaO_2、PCO_2、吸气峰压(PIP)、平均气道压(Paw)、呼气末压(EEP)、HR、平均动脉压(MAP)、肺动脉压(PAP)和肺毛细血管楔压(PCWP)均无显著变化(P>0.05)。提示:HFJV+CWC除保留单纯HFJV时气道开放、气道低压、良好的血液氧合、不影响循环功能等特点外,还具有增加呼气动力,改善肺泡通气,显著促进CO_2排除等优点。 相似文献