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51.
Heart rate (HR) as an estimator of oxygen consumption (VO(2) ) usually requires HR to be individually calibrated in a separate test. This study examined the validity of a new HR - and HR variability-based method (Firstbeat PRO heartbeat analysis software) in the estimation of VO(2) in real-life tasks. The method takes into account the respiration rate determined from HR variability and the differences in the on/off dynamics of HR and VO(2) , and no calibration tests are needed. Ten men and nine women performed 25 tasks representing different types of daily activities. Portable devices were used to measure R-to-R intervals (ECG), VO(2) and respiration rate. In pooled regression analysis, the estimated VO(2) accounted for 87% of the variability in the actual VO(2) , SEE 3·5 ml min(-1) kg(-1) (1 MET). At group level, the method underestimated slightly the measured VO(2) (mean difference - 1·5 ml min(-1) kg(-1) or - 0·4 METs). Some of the values at low exercise intensities were markedly underestimated, but the agreement was better during light and heavy activities. The limits of agreement for the data were from -8·4 to 5·4 ml min(-1) kg(-1) or from -2·4 to 1·5 METs. At individual level, the average deviations of the predicted VO(2) ranged from -1·0 to 0·6 METs and R(2) from 0·77 to 0·94, respectively. The present data indicate that the prediction method may be considered sufficiently accurate to determine the average VO(2) in field use, but it does not allow precise estimation of VO(2) .  相似文献   
52.
A retrospective analysis of 127 surgically treated cases of T-1, T-2 carcinoma of oral tongue during the period 1987-1990 was undertaken. 68.5 per cent (87) underwent hemiglossectomy and 31.5 per cent (40) underwent wide excision. There were loco-regional recurrences in 22 per cent (27). In the hemiglossectomy group 9 per cent (8 of 87) had local recurrences compared to 25 per cent (10 of 40) of wide excision group, (P = 0.01). Mean disease free survival was 40 months and 33 months for hemiglossectomy group and wide excision group respectively, (P = 0.006). It is seen that local recurrences are significantly less for the hemiglossectomy group compared to the wide excision group.KEY WORDS: Disease free survival, Early cancer, Recurrence, Surgery, Tongue  相似文献   
53.
空气喷磨和酸蚀与树脂突超微结构的关系   总被引:2,自引:0,他引:2  
目的 体外评价5种处理方法对树脂突超微结构的影响。方法 对照组:对1颗离体磨牙常规预防性树脂充填。其余4颗磨牙用空气喷磨处理,分别用50μ和27μ氧化铝微粒,酸处理其中2颗磨牙。窝洞用复合树脂充填后,用10%盐酸溶解牙釉质,扫描电镜观测树脂突超微结构。结果 对照组呈典型窝状结构。空气喷磨的树脂突呈不规则结构,结合酸蚀的树脂突表面更加粗糙。结论 空气喷磨具有一定的蚀刻作用但不如酸蚀作用强。  相似文献   
54.
AIM To study the clonality of the esophageal carcinosarcoma by using molecular approaches.METHODS Two esophageal carcinosarcomas were included in the study. Tumor area from dysplasticlesion, squamout cell carcinoma, basaloid cell carcinoma and spindle cell elements were microdissectedseparately. Each element was analyzed with 14 microsatellite markers and direct sequenced for p53 gene andras gene mutation.RESULTS Both tumors displayed a typical histologic feature of carcinosarcoma. Both cases showed thedivergent differentiation by immunohistochemistry study. In case 1 the identical LOH at p53 and hMLH1 lociwas detected. The heterogenous LOH was detected only in carcinosarcoma at RB1 and BRCA1 loci, whilethe LOH at ACTC locus was seen only in sarcoma. The same mutation of the splice site of exon 6-intron 6displayed in the two tumor elements. In case 2, a coordinate LOH at RB locus was demonstrated in threetypes of tumor elements: sqamous carcinoma, basaloid carcinoma and spindle cell element. A heterogenousLOH was seen only in spindle cells at TAP1 locus. No mutation in exon 5-8 of p53 gene has been found incase 2. No mutation of K-ras gene was found.CONCLUSION Although the different differentiation, the two elements of esophageal carcinosarcoma mayhave a single clonality. The p53 gene mutation occurred before the two differentiation directions switched.The distinct molecular genotype can be determined through molecular biological analysis. The microsatelliteprofiling can serve as an approach to find out which genetic alteration occurs before or after thedifferentiation is determines.  相似文献   
55.
冠状动脉狭窄的16层螺旋CT造影检查   总被引:4,自引:1,他引:3  
目的以常规X线冠状动脉造影为标准,评价16层螺旋CT(MSCT)无创性检查冠状动脉及诊断冠状动脉狭窄的价值。资料与方法65例临床初诊为冠心病,无冠状动脉成形术和搭桥术史的患者,在冠状动脉16层MSCT造影检查后,回顾性重建心电门控轴位图像,并采用容积成像(VR)、多平面重建(MPR)、曲面MPR、最大密度投影(MIP)等后处理方法,对所有冠状动脉及其分支进行重建,统计可供临床评价的、管径≥1.5mm的冠状动脉段,以选择性冠状动脉造影(SCA)为标准,对比分析MSCT诊断冠状动脉显著性狭窄(管腔平均直径缩小超过50%)的准确性。其中8例在检查前心率超过80次/min的患者使用了B受体阻滞剂。结果93%的冠状动脉节段和94%的冠状动脉主干可供评价,不能评价的主要原因分别为:心脏运动伪影(58%),致密钙化(28%)和管腔显影不良(14%)。除外不能评价的冠状动脉,按节段和主干分类,MSCT诊断冠状动脉显著性狭窄的敏感性和特异性分别达到92%、98%和95%、97%。结论无需常规使用B受体阻滞剂,16层MSCT冠状动脉造影即可获得较好的图像质量用于诊断冠状动脉狭窄,是一种值得临床医师信赖的检查冠状动脉有无狭窄的非创伤性方法。  相似文献   
56.
This study examined the relation of self-reported stress to cardiac autonomic modulation in real-life conditions. The participants for the study were healthy male (N = 59) and female (N = 40) employees (age 40 ± 10 years). A single-item question and a 14-item questionnaire on perceived stress were administered to the participants before the experimental night. RR-intervals (RRI) were recorded during night sleep and an orthostatic test after awakening at home. The RRI data were analyzed for heart rate (HR) and heart rate variability (HRV) in time and frequency domains. Nocturnal urinary stress hormone (cortisol, adrenal and noradrenal) secretion was also analyzed. Based on the self-reported stress, the participants were divided into either low or high stress group. The results showed that higher incidence of stress symptoms was significantly associated with lower HRV in the orthostatic test regardless of age and gender. Differences between the stress groups in HRV indices were approximately 20–50 and 30–75% in supine and standing positions, respectively. No difference was found in nocturnal HR, HRV, or stress hormone secretion between the stress groups. Higher incidence of stress symptoms was significantly associated with greater decrease of HRV from night sleep to the orthostatic test, as a response to awakening. In conclusion, the present findings support the view that autonomic modulation measured in the orthostatic test, but not during night sleep, is related to self-reported stress.  相似文献   
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59.
Methodological problems have limited the number of studies on heart rate variability (HRV) dynamics immediately after exercise. We used the short-time Fourier transform method to study immediate (5 min) and slow (30 min) recovery of HRV after different high-intensity exercise interventions. Eight male athletes performed two interval interventions at 85% and 93% (IV85 and IV93) and two continuous interventions at 80% and 85% (CO80 and CO85) of the velocity at VO2max (vVO2max). We found no increase in high frequency power (HFP), but low frequency (LFP) and total power (TP) increased ( P <0.05) during the first 5 min of the recovery after each intervention. During the 30-min recovery, HFP, LFP and TP (1) increased slowly toward resting values, but HFP remained lower ( P <0.01) than at rest, (2) were lower ( P <0.05) after IV93 and CO85 when compared with IV85 and CO80, respectively and (3) were lower ( P <0.01) after CO85 when compared with IV85. HRV recovery was detected during the immediate recovery after interventions. Increased exercise intensity resulted in lower HRV both in interval and in continuous interventions. In addition, when interval and continuous interventions were performed at a similar workload, HRV was lower after continuous intervention.  相似文献   
60.
Studies of the cholesterol lowering effect of statin therapy as a function of low-density lipoprotein (LDL)-receptor mutation type have not produced a clear picture, possibly because they included patients with several different kinds of LDL-receptor mutations. We studied the response to treatment with fluvastatin in 28 patients with heterozygous familial hypercholesterolemia as a result of a receptor-negative mutation (Trp23-stop) and in 30 patients with a receptor-binding defective mutation (Trp66-Gly) to test the hypothesis that response to treatment depends on the type of mutation. Patients were randomized to 12 weeks of treatment with fluvastatin 40 mg daily and 12 weeks of placebo treatment, preceded by a placebo run-in period of 8 weeks in a double-blind, cross-over design. Untreated plasma concentrations of lipids and lipoproteins were similar in the two groups of patients. Plasma cholesterol and LDL cholesterol response to therapy tended to be less marked in receptor-binding defective patients, but the differences were not statistically significant. A tabulation of the results of the present and earlier studies suggests that differences in treatment response as an apparent function of LDL-receptor gene mutational type occur mainly in populations with recent genetic admixture (<400 years). In such populations, persons with the same mutation in the LDL-receptor gene are more likely to share other but undetermined genetic variations affecting the pharmacology of statins.  相似文献   
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