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61.
J. Milliez H. Legrand F. Goupil J. Vaquier F. Rochart G. Breart C. Sureau 《European journal of obstetrics, gynecology, and reproductive biology》1981,11(4):251-261
This third part of the paper deals with the study of the relationships between fetal movements, fetal heart rate accelerations associated with such movements, fetal heart rate instability and neonatal outcome.No correlation has been found between absence of fetal movements and neonatal distress.A correlation has been found between the lack of fetal heart rate accelerations, the flatness of the record and poor neonatal outcome.In extreme situations (i.e. flatness in less than 10% of the record or in more than 80%) the presence or absence of accelerations does not add further useful information. Such information, however, is gained in the intermediary situations (the ‘combined’ recordings) and particularly when the record is between 51 and 80% flat where there appears to be an 85.6% risk to the fetus.Consequently, when trying to analyse an antenatal record it seems advisable to take primarily into account the percentage of flat recordings (providing the records are numerous enough and of sufficient length). Then, in records between 10 and 50% flat, the presence or the lack of spontaneous decelerations requires consideration whereas, when the record is between 51 and 80% flat, it is the presence or absence of fetal heart rate accelerations which is important. 相似文献
62.
<正>在碘缺乏病区,居民甲状腺肿患病率在年鹅分布上的特征,可用二次抛物线加以描述[l].根握资料类型的不同,可选择更为适合的三次抛物线来描述.根据现场调查资料,本文采用三次抛物线方法进行配合,并将配合结果与二 相似文献
63.
W. Pearl 《Pediatric cardiology》1996,17(3):135-136
The objective of this study was to determine if gender, age, and heart rate affect corrected QT intervals in children. Electrocardiograms
were obtained from 781 healthy children 10–18 years of age. Corrected QT intervals were significantly (p < 0.0005) greater for girls than for boys in the entire population and for each age group over 14 years. The corrected QT
interval varied inversely with age and directly with heart rate. Hence gender, age, and heart rate should be considered when
diagnosing long QT syndrome. 相似文献
64.
Henry D. Mcintosh 《Clinical cardiology》1996,19(11):846-856
The announcement of the National Heart Attack Alert Program by the National Heart, Lung and Blood Institute in June of 1991 prompted leaders of the Florida Chapter of the American College of Cardiology to develop a statewide program to reduce the morbidity and mortality from acute myocardial infarctions within Florida. It became apparent that the success of such a program would require the prompt institution of thrombolytic agents or other revascular-ization procedures in appropriate patients. No longer could the decision regarding institution of therapy await discussion by telephone and/or the arrival at the emergency department (ED) of the patient's primary care physician or cardiologist. Efforts to establish appropriate protocols for therapy revealed that many of the 25,000 or more physicians currently staffing the 5,600 or so EDs in this country were moonlighting residents or practitioners from a variety of specialties or subspe-cialties with limited or no formal EM training. Furthermore, it was learned that there were in the entire country only about 800 postgraduate, year-one Council for Graduate Medical Education accredited training positions. There were only 21 such training positions in the entire state of Florida. The reasons for these deficiencies are discussed and a challenge to correct this person power crisis is issued, not principally to the leadership of EM, but to the entire medical profession. 相似文献
65.
Short and long term effects of exercise training on the tonic autonomic modulation of heart rate variability after myocardial infarction 总被引:3,自引:0,他引:3
Malfatto G.; Facchini M.; Bragato R.; Branzi G.; Sala L.; Leonetti G. 《European heart journal》1996,17(4):532-538
We studied the effects of cardiac rehabilitation on the sympathovagalcontrol of heart rate variability in 30 patients after a first,uncomplicated myocardial infarction. Twenty-two patients completed8 weeks of endurance training (trained), while eight decidednot to engage in the rehabilitation programme for logisticalreasons, and were taken as untrained controls. Age, site ofinfarction, ejection fraction, ventricular diameter and stresstest duration were similar in the two groups at baseline. Heartrate variability was evaluated 4 weeks after infarction beforestarting rehabilitation, and repeated 8 weeks and one year laterin both trained and untrained patients. Measures of heart ratevariability, obtained from both time- and frequency- domainanalysis of a 15 min ECG recording in resting conditions, wereas follows: mean RR interval and its standard deviation (RRSD),the mean square successive differences (MSSD), the percent ofRR intervals differing >50 ms from the preceding RR (pNTN50),the low and high frequency components of the autoregressivepower spectrum of the RR intervals and their ratio (LF/HF).At baseline, heart rate variability was similar in trained anduntrained patients. In the short term (8 weeks after infarction),training increased RRSD by 25% (P<0·01), MSSD by 69%(P<0·01), pNN50 by 120% (P<0·01), and reducedLF/HF ratio by 30% (P<0·01). The effects persistedafter one year in trained patients. In untrained patients, theautonomic control of heart rate variability did not change 8weeks after myocardial infarction and was only slightly modifiedby time. Thus, exercise training, performed for 8 weeks aftera myocardial infarction, modifies the sympathovagal controlof heart rate variability toward a persistent increase in parasympathetictone, known to be associated with a better prognosis. This maypartly account for the favourable outcome of patients who undergorehabilitation. 相似文献
66.
Azra Raza Harvey D. Preisler Ya Qin Li Richard A. Larson Jack Goldberg George Browman John Bennett Hans Grunwald Ralph Vogler Cathi Kukla 《American journal of hematology》1993,42(4):359-366
A pilot study was conducted of the biological characteristics of the leukemia cells of newly diagnosed patients with poor prognosis acute myelogenous leukemia (AML). This study included measurements of the pretherapy proliferative rate of the leukemia cells in vivo, assessment of differentiation in vivo during remission induction therapy, and the level of expression of the fms, myc, and IL1β genes in pretherapy leukemia cells. Short cell cycle times were characteristic of the best prognostic category and were associated with a rapid reduction in marrow leukemia cells in cytosine arabinoside (araC)-sensitive patients. Expression of c-fms was associated with rapid reduction in marrow leukemia cells during araC therapy and with a successful treatment outcome. Expression of the IL1β gene was associated with short remissions. These studies suggest that when compared to newly diagnosed standard prognosis AML, the leukemia of poor prognosis patients is more likely to exhibit long cell cycle times, low levels of fms expression, and is less likely to be associated with myeloid differentiation during remission induction therapy. © 1993 Wiley-Liss, Inc. 相似文献
67.
The accumulation of oxygen free radicals is reported to occur in the organs subjected to temporary ischemia followed by reperfusion, resulting in the fatal outcome of the animals. The effects of human SOD, a representative scavenger of oxygen free radicals, on the survival rates were investigated in the rats with temporary splanchnic ischemia. The temporary ischemia was induced by the occlusion of anterior mesenteric and celiac arteries for 30min under anesthesia. Prior and after treatment with 2mg/100g of human SOD, iv or sc, produced significant improvements in survival rates. Human SOD, cloned from human placenta DNA and expressed in microorganisms, has extreme homogeneity. The results suggest the possible introduction of human SOD into clinical field as an effective scavenger of oxygen free radicals.(Ogawa R, Bitoh H, Ohi Y: The effect of human SOD on the survival rate in rats with temporary splanchnic ischemia. J Anesth 2: 41–45, 1988) 相似文献
68.
Improvement in the Treatment of Childhood Cancer: Analysis of Survival Data from the National Children's Hospital (1965-1987) 总被引:2,自引:0,他引:2
Tsunematsu Yukiko; Koide Ryo; Kobayashi Noboru 《Japanese journal of clinical oncology》1988,18(4):309-320
Developments in the treatment of childhood cancer have beenevaluated in patients who had been treated in the National Children'sHospital from 1965 to 1987. The total number of patients was867, of which leukemia accounted for 376, malignant lymphoma61, neuroblastoma 174, Wilms' tumor 55, yolk sac tumor 29, rhabdomyosarcoma36 and hepatoblastoma 30. Patients were divided into three timeintervals: the 1960s, 1970s and 1980s. A marked improvementin five-year survival was recognized in Wilms' tumor and yolksac tumor, amounting to 80%, followed by rhabdomyosarcoma, acutelymphoblastic leukemia and malignant lymphoma. There was noimprovement in patients with acute non-lymphoblastic leukemia,neuroblastoma and hepatoblastoma. Prognostic factors for neuroblastomawere further analyzed, and the age of onset and stage of diseasewere found to have remained constant for 23 years. Factors relatingto the improvement of survival were discussed. 相似文献
69.
Summary The purpose of this study was to investigate the relationship between threshold points for heart rate (
) and blood lactate (Th1a) as determined by two objective mathematical models. The models used were the mono-segmental exponential (EXP) model of Hughson et al. and the log-log (LOG) model of Beaver et al. Inter-correlations of these threshold points and correlations with performance were also studied. Seventeen elite runners (mean, SD = 27.5, 6.5 years; 1.73, 0.05 m; 63.8, 7.3 kg; and maximum oxygen consumption of 67.8, 3.7 ml · kg–1 · min–1) performed two maximal multistage running field tests on a 183.9-m indoor track with inclined turns. The initial speed of 9 km · h–1 (2.5 m · s–1) was increased by 0.5 km · h–1 (0.14 m · s–1) every lap for thef
c test and by 1 km · h–1 (0.28 m · s–1) every 4 min for the la test. After fitting the la or thef
c data to the two mathematical models, the threshold speed was assessed in the LOG model from the intersection of the two linear segments (LOG-1a; LOG-f
c) and in the EXP model from a tangent point (TI-1a; TI-f
c). Th1a and
speeds computed with the two models were significantly different (P<0.001) and poorly correlated (LOG-1a vs LOG-f
c:r=0.36, TI-1a vs TI-f
c:r=0.13). In general,
were less well correlated with performance than Th1a. With two different objective mathematical models, this study has shown significant differences and poor correlations between Th1a and
. Thus thef
c inflection point with Conconi's protocol is a poor indicator of the la breakpoint with a conventional multistage protocol and a weaker indicator of running performance. 相似文献
70.
Effects of different inspiratory concentrations of sevoflurane (fluorometyl-1,1,1,3,3,3,-hexafluoro-2-propylether) on blood pressure, heart rate and efferent activities of cardiac sympathetic, cardiac parasympathetic and renal sympathetic nerves were examined using rats either under the resting condition or during noxious mechanical stimulation of a hindpaw. Under the resting condition, an increase in the inspiratory concentration of sevoflurane from 2.1% to 4.2% gradually caused a decrease in blood pressure and heart rate. With the increase in the sevoflurane concentration, cardiac sympathetic nerve activity decreased, whereas renal sympathetic nerve and cardiac parasympathetic nerve activities did not change significantly. When noxious mechanical stimulation was applied to a hind-paw by pinching, blood pressure and heart rate, renal sympathetic and cardiac sympathetic nerve activities all increased at the 2.1% concentration of sevoflurane. The responses of these parameters were attenuated at the 3.1% concentration of sevoflurane and almost disappeared at the 4.2% concentration. Cardiac parasympathetic nerve activity did not change significantly during the pinching stimulation throughout the 2.1–4.2% concentration increase.(Kurosawa M, Meguro K, Nagayama T et al.: Effects of sevoflurane on autonomic nerve activities controlling cardiovascular functions in rats. J Anesth 3: 109–117, 1989) 相似文献