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31.
目的:本研究旨在探讨多巴酚丁胺对缺血性心肌病(ICM)患者左心室(LV)充盈功能的影响,并确定峰值负荷时限制性充盈型(RFP)是否具有预后预测价值。背景:ICM患者峰值负荷时RFP的预后价值尚属未知。方法:在静息和负荷情况下,采用多普勒超声心动检查研究了69例ICM患者;RFP定义为跨二尖瓣E/A比≥1.0、等容舒张时间(IVRT)〈80ms及E波减速时间(EDT)〈120ms。结果:69例患者中有42例静息时出现RFP,其中有24例患者负荷情况下转变为非RFP(EA),18例患者RFP持续存在(EE);69例患者中27例静息和峰值负荷时均无RFP(AA)。 相似文献
32.
Althin/TIAN System1000 HDF血透机常见故障及检修 总被引:1,自引:0,他引:1
Althin/TIAN System1000 HDF血透机是美国Baxter公司较为先进的血液透析滤过装置。它采用的是平恒腔式的定容超滤控制系统.使得超滤量的控制更为精确。非在线式血液滤过的设计彻底保证了滤过液的安全性。人性化的液晶触摸屏给操作和维修带来及大的方便。由于血透机特殊的工作环境.年久的机器会出现一些问题。现将几例常见故障的检修提供给同行,供同行参考。 相似文献
33.
乳腺囊性增生病癌变过程中部分因素变化的意义 总被引:3,自引:0,他引:3
检测乳腺囊性增生病(FCD)经不典型增生到癌变部分因素的变化。结果提示:从因明显FCD症状活检至癌变为2~10年;从Ⅱ级以上不典型增生到临床癌变需2~7年;癌变率为3.1%。FCD患者存在性激素分泌调控失常,血浆雌激素和催乳素含量增加,导致上皮细胞增生。乳腺一般性增生细胞的DNA含量和超微结构与正常乳腺上皮细胞相似;无肿瘤相关抗原及异常基因产物表达。而发生在一般性增生基础上的不典型增生则呈现细胞基因物质DNA含量增加,部分为超4C的多倍体细胞;同时出现细胞膜和细胞核超微结构异常;雌激素受体含量增加,对性激素的依赖性和敏感性增强;部分不典型增生细胞出现胚胎性肿瘤相关抗原和异常基因产物表达。随不典型增生程度加重至乳腺癌,上述诸因素的变化趋势具有明显规律性。提示FCD上皮细胞从一般性增生经不典型增生至乳腺癌为细胞生物学连续逐渐变化的过程。部分不典型增生细胞中具有癌倾向的细胞生物学行为异常和表型变化与乳腺癌发生密切相关。细胞核DNA含量等异常变化及程度可作为乳腺癌前病变发展程度的客观标志 相似文献
34.
Jun Gu Yang O Huh Feng Jiang Nancy P Caraway Jorge E Romaguera Tanweer M Zaidi Ricardo L Fernandez Huazhong Zhang Issa F Khouri Ruth L Katz 《Modern pathology》2004,17(5):553-560
Mantle cell lymphoma is non-Hodgkin's B-cell lymphoma characterized by the t(11;14)(q13;q32) translocation. Peripheral blood involvement of mantle cell lymphoma is usually associated with a poor prognosis and therefore, its identification is clinically important. In this study, we performed cyclin D1/IgH-probe fusion fluorescence in situ hybridization analysis on 223 peripheral blood samples: 185 from 125 mantle cell lymphoma patients, and 38 normal controls. The cutoff values for the test were established using normal controls. Flow cytometry on peripheral blood and corresponding bone marrow samples was used to evaluate this test. In all, 26% of the 185 peripheral blood samples and 27% of the 161 corresponding bone marrow samples were flow cytometry positive for mantle cell lymphoma. The mean numbers of single and- double-fusion signals and the mean number of CD5/CD19-positive cells, absolute blood lymphocyte count, and white blood cell count were significantly higher in peripheral blood and corresponding bone marrow samples with mantle cell lymphoma-positive flow cytometry. Double-fusion signals were more specific than single-fusion ones. Fluorescence in situ hybridization was far more likely to be positive for mantle cell lymphoma when the peripheral blood and the corresponding bone marrow samples had positive flow cytometry results or morphology (P<0.01). Our study indicates that cyclin D1/IgH-fusion fluorescence in situ hybridization analysis could be used to determine the presence and character of circulating mantle cell lymphoma cells in peripheral blood, thus enhancing our ability to evaluate leukemic mantle cell lymphoma and minimum residual disease. 相似文献
35.
Hemorrhagic disseminated intravascular coagulation (DIC) associated with the presence of underlying advanced or metastatic tumors are often difficult to control by conventional methods. We report the use of recombinant activated factor VII (rFVIIa) in patients with cancer and bleeding secondary to DIC. A total of 18 patients with cancer met pre-defined criteria for DIC. All patients had failed to respond to transfusion with blood products and treatment of the underlying malignancy prior to the introduction of rFVIIa. The median laboratory data at the time of treatment with rFVIIa were as follows: hemoglobin, 7.7 g/dl; platelets, 54 x 10(9)/l; prothrombin time, 21 s; activated partial thromboplastin time, 41 s fibrinogen, 83 mg/dl; D-dimer, 17 microg/ml; and antithrombin, 32%. The dose of rFVIIa was 90 microg/kg and the median number of doses administered was 5 (range, 3-10). Serial measurements of coagulation parameters were obtained at frequent intervals during treatment with rFVIIa. Of the 18 patients, 15 responded with cessation of bleeding and improvement in coagulation data. The prothrombin time and activated partial thromboplastin time normalized in all responding patients within 24 h of treatment. The median fibrinogen was 214 mg/dl while the median D-dimer was 6 microg/dl at 48 h following the administration of rFVIIa. No thromboembolic complications were observed following rFVIIa. Our data provide evidence that rFVIIa can be used successfully to control the hemorrhagic episodes associated with DIC. Although this type of treatment appears to be safe, close monitoring of the patients is warranted. 相似文献
36.
Margaret Seto-Poon Melanie Madronio Jason P Kirkness Terence C Amis Karen Byth Chong Lee Lim 《Clinical neurophysiology》2005,116(5):1172-1180
OBJECTIVE: To examine response decrement of the recently reported inspiratory skin conductance response (SCR) [Lim CL, Seto-Poon M, Clouston PD, Morris JG. Sudomotor nerve conduction velocity and central processing time of the skin conductance response. Clin Neurophysiol 2003;114:2172-80]. METHODS: Twelve healthy adult volunteers performed 3 tasks (A) a control task of maintaining tidal breathing and then two randomized tasks, (B) a deep inspiration to a target oral pressure and (C) tapping with a finger. Each task was performed 30 times on cue every 20s in 3 runs with 5 min of rest between runs. The SCR, oral pressure, airflow, inspired volume and cue signal were recorded continuously and analysed offline. SCR amplitude was logarithmically transformed and then statistically analysed, using a linear mixed effects model, as a function of run number, trial number and absolute error between target and actual oral pressures. RESULTS: Inspiratory efforts elicited exponentially decreasing SCR amplitude with increasing trial number during each run (P < 0.0001). After adjusting for trial number, the mean SCR amplitude of the second and the third run were, respectively, 24.2 (95% CI (0.175, 0.336), P < 0.001) and 14.4% (95% CI (0.104, 0.200), P < 0.001) of the first run amplitude. CONCLUSIONS: Volitional deep inspiration reliably activates an SCR that exhibits response decrement with repetition, which may be habituation. SIGNIFICANCE: The volitional inspiratory SCR may assist in the assessment of sympathetic autonomic status in patients with peripheral afferent neuropathy. 相似文献
37.
Do commonly used oral antihypertensives alter fetal or neonatal heart rate characteristics? A systematic review. 总被引:1,自引:0,他引:1
E J Waterman L A Magee K I Lim A Skoll D Rurak P von Dadelszen 《Hypertension in pregnancy》2004,23(2):155-169
OBJECTIVE: To examine fetal (FHR) and neonatal heart rate patterns following use of common oral antihypertensives in pregnancy. METHODS: A systematic review of randomized controlled trials (RCTs), observational studies (N >/= 6 women), and animal studies. Data were abstracted (two reviewers) to determine relative risk (RR) (or risk difference (RD) for low event rates) and 95% CI. RESULTS: Eighteen RCTs (1858 women), one controlled observational study (N = 22), and seven case series (N = 117) were reviewed. Most hypertension was pregnancy-induced (N = 14 studies). The FHR was assessed by cardiotocogram (CTG) (N = 17 studies (visual interpretation); 1 study (computerized CTG), or umbilical artery velocimetry (N = 4). Four studies examined neonatal heart rate. In placebo-controlled RCTs (N = 192 women), adverse FHR effects did not differ between groups [9/101 (drugs) vs. 7/91 (placebo); RD 0.02, 95% CI (- 0.06, 0.11); chi2 = 1.02]. In six drug vs. drug RCTs (295 women), adverse FHR effects did not differ between groups [29/144 (methyldopa) vs. 42/151 (other drugs); RR 0.72, 95% CI (0.49, 1.07); chi2 = 0.69]. In one labetalol vs. placebo trial, neonatal bradycardia did not differ between groups [4/70 (labetalol) vs. 4/74 (placebo); OR 1.06, 95% CI (0.26, 4.39)], while in three drug vs. drug RCTs, neonatal bradycardia was not observed (0/24 vs. 0/26). CONCLUSIONS: Available data are inadequate to conclude whether oral methyldopa, labetalol, nifedipine, or hydralazine adversely affect fetal or neonatal heart rate and pattern. Until definitive data are available, FHR changes cannot be reliably attributed to drug effect, but may be due to progression of the underlying maternal or placental disease. 相似文献
38.
39.
无症状性炎性前列腺炎对血清PSA、fPSA的影响 总被引:3,自引:0,他引:3
目的 探讨无症状性炎性前列腺炎(NIH分类Ⅳ型)对血清PSA、fPSA的影响。方法 对比分析36例NIH分类Ⅳ型、42 例有症状性慢性前列腺炎(NIH分类ⅢA型)患者以及22例健康对照组的血清PSA、fPSA、fPSA/tPSA之间的差异。结果 血 清PSA、fPSA、fPSA/tPSA在Ⅳ型和ⅢA型前列腺炎患者间差异无显著性(P>0.05),但与正常对照组比较差异有显著性(P< 0.01)。结论 NIH分类Ⅳ型前列腺炎可引起血清PSA、fPSA升高。对无症状、高血清PSA患者行前列腺活检前,应考虑到患 Ⅳ型前列腺炎的可能。 相似文献
40.
A study of the interaction of alcohol drinking and tobacco smoking among French cases of laryngeal cancer. 总被引:3,自引:0,他引:3
P Guénel J F Chastang D Luce A Leclerc J Brugère 《Journal of epidemiology and community health》1988,42(4):350-354
Laryngeal cancer represents an important cause of cancer in France, and the individual effects of alcohol and tobacco on this cancer site are well known. However the problem of the interaction between these agents is less extensively documented, and the role of the high consumptions of alcohol has not been studied frequently. A case-control analysis was undertaken to investigate the joint effect of alcohol and tobacco by comparing 197 glottic and 214 supraglottic cancer cases to 4135 controls representative of the French general population. Heavy drinkers were available from the two groups of cases, the highest alcohol category being equivalent to a consumption of more than 2 litres of wine per day. The relative risks estimated for heavy drinkers and smokers were high, and the results indicated an even stronger effect of alcohol drinking and tobacco smoking on the upper part of the laryngeal region. Additive and multiplicative models were fitted to the data. The multiplicative hypothesis was found to be the most appropriate, implying that the risks associated with alcohol and tobacco multiply when the exposures occur simultaneously. The public health implications of this result and the contribution of heavy drinkers and smokers to the frequency of upper respiratory and digestive tract cancers are discussed. 相似文献