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11.
12.
To investigate whether the secular trend for growth in Dutch children still exists, the Oosterwolde I study of 1980 was repeated in 1989. A persisting secular trend was visible for height while the z scores of body proportions show no change during the past 10 years, which suggests that there is no change in the timing of puberty. 相似文献
13.
Integrated plasma cortisol concentration in children with asthma receiving long-term inhaled corticosteroids. 总被引:2,自引:0,他引:2
We assessed the effect of long-term therapy with inhaled beclomethasone dipropionate (BDP) on the pituitary-adrenal axis, by measuring the integrated concentration (IC) of plasma cortisol in eight children with asthma (age, 6-16 years) who regularly used inhaled BDP in doses ranging from 8 to 26.5 micrograms/kg (200-450 micrograms/day) for 6 months to 4 years. The control group included six children (age, 6-16 years) who had the IC of plasma cortisol measured as part of an endocrinological evaluation and were found to be healthy. Cortisol concentration was measured in blood samples collected continuously over a 24-hr period. Mean IC of plasma cortisol in the study group was significantly lower than in the healthy controls (mean +/- SD, 4.9 +/- 3.3 vs 9.1 +/- 1.9 micrograms/mL; P less than 0.02). Cortisol response to 0.25 mg ACTH (iv) was abnormal in one of the eight BDP-treated patients. No correlation was found between IC of plasma cortisol and the BDP dose, severity of asthma, height percentile, or the Tanner stage. We conclude that long-term therapy, even with relatively conventional doses of inhaled BDP may cause reduction in the normal physiological secretion of cortisol. The clinical relevance of low IC of plasma cortisol is not clear, but it may reflect partial suppression of the pituitary-adrenal axis. 相似文献
14.
VILHJALMUR FINSEN 《Journal of internal medicine》1988,223(5):443-449
Questionnaire responses from 120 men and 337 women over the age of 50 years were studied to determine the prevalence of back pain among the elderly. In order to gain a rough indication of the back pain among elderly women which might be due to osteoporosis, the prevalence was compared in the two sexes. The prevalence of back pain without radiation to the legs and concomitant morbidity was found to be similar among men and women up to the 70–79-year age-group. After this age the prevalence was higher in women. Those with exceptional loss of body height or kyphosis had a high prevalence of back pain, while those who had sustained previous hip or radius fractures did not. There was increasing prevalence of back pain among women with increasing number of previous fractures. The study gives little indication of serious morbidity of osteoporosis in the form of back pain before very old age. 相似文献
15.
Comparison between a new acceleration transducer and a conventional force transducer in the evaluation of twitch responses 总被引:1,自引:0,他引:1
T. Itagaki K. Tai N. Katsumata H. Suzuki M.D. Ph.D. 《Acta anaesthesiologica Scandinavica》1988,32(4):347-349
An acceleration transducer elicits an output voltage proportional to the deformation of the piezo crystal, in accordance with the twitch responses of the applied fingers. The reliability of such a transducer was evaluated by comparing induced twitch responses with those from a force transducer applied on the contralateral arm of an individual during neuromuscular block with vecuronium. The results obtained from twitch responses with the acceleration transducer during neuromuscular block were almost identical to those obtained with the force transducer. Also, the twitch heights due to acceleration of the examined thumb correlated extremely well with the twitch height due to twitch tension with the force transducer. It is concluded that the acceleration transducer may be a useful and reliable device for monitoring neuromuscular block, although responses during tetanic stimulation such as tetanic fade cannot be determined by the transducer. 相似文献
16.
As part of a longitudinal developmental study of newborn and young Dutch twins, data on weight and height are collected. Birth weight and height are available for 3275 pairs; data on growth, for 1390 pairs. 相似文献
17.
M. J. Baurain M.D. B. S. Dernovoi A. A. D'Hollander D. A. Hennart F. R. Cantraine 《Acta anaesthesiologica Scandinavica》1996,40(5):574-578
Background: Since neostigmine was introduced for reversal of neuromuscular block, there has been controversy about the optimum dose for antagonizing neuromuscular block. The purpose of this study was to characterise recovery of neuromuscular transmission following a vecuronium-induced block 15 min after neostigmine administration using different stimulation patterns, and to determine the effects of different doses of neostigmine given at various pre-reversal twitch heights. Methods: Adductor pollicis (AP) mechanical activity in response to low (0.1 and 2 Hz) and high (50 and 100 Hz) frequency stimulation, was recorded 15 min after 20, 40 and 80 μg/kg neostigmine, given to reverse a vecuronium-induced block at 10, 25 and 50% pre-reversal twitch height (TH). Fifty four ASA class I and II anaesthetised (methohexital, fentanyl, N2O/O2) young adult patients were studied and randomly allocated into 9 groups of 6 patients each. Results: In contrast to twitch height (TH) and residual force after 50 Hz, 5 s tetanic stimulation (RF50Hz), the greater sensitivity of train-of-four (TOF) ratio and residual force after 100 Hz, 5 s tetanic stimulation (RF100Hz) points out the best reversal conditions (prereversal TH and the optimal neostigmine dose) (P<0.001, two-way analysis of variance). The highest reversal scores (about 0.9 TOF ratio and RF100Hz) were obtained when 40 μg/ kg of neostigmine was given at 25 and 50% TH. A 0.9 TOF ratio was also observed when 40 μg/kg of neostigmine was given at 10% TH, but, under these conditions, RF100Hz was only 0.6 (P<0.05, Duncan test). Conclusion: To optimise the reversal action of neostigmine in order to obtain the highest neuromuscular transmission recovery (0.9 TOF ratio and RF100Hz) during a vecuronium-induced neuromuscular block, the 40 μg/kg dose has to be given at 25 to 50% recovery of TH. 相似文献
18.
H. Klüter I. Dörges E. Maass T. Wagner H. Bartels H. Kirchner 《Annals of hematology》1996,73(2):85-89
Random-donor platelet concentrates (PC) prepared from pooled buffy coats have recently been described as an alternative method
for platelet preparation. We evaluated such PCs in the clinical setting compared with a standard PC from platelet apheresis.
PCs were prepared either from pools of buffy coats (BC-PC) or from single donors (SD-PC) with the cell separator CS-3000 plus.
PCs were stored for up to 5 days before transfusion. We compared fresh PC (day 1) with stored (day 2–3) and long-stored PC
(day 4–5). For analysis, platelet increment in the recipient was determined immediately and 16–22 h (mean 20 h) after transfusion,
corrected for total body area and transfused platelets (CCI). A total of 316 PCs were administered to 36 thrombocytopenic
patients suffering from various hematological disorders. Patients with detectable HLA or platelet-specific antibodies or splenomegaly
were excluded from the study. Mean platelet content of the PC was 262×109 for BC-PC and 251×109 for SD-PC. The 20-h CCI after transfusion of fresh PC was slightly higher with BC-PC than with SD-PC (14.5 versus 11.9;p=0.19), but values did not differ significantly between the two types of PC on any day of storage. For BC-PC, 20-h CCI decreased
with further storage by 30% (10.2;p=0.02). For SD-PC a decrease by 9% was not significant. In conclusion, platelet concentrates prepared from pools of buffy
coats showed excellent transfusion results when administered fresh, but storage decreased the CCI by 30%. No significant difference
from PCs from plateletpheresis was observed on any day of storage. Both types of platelet concentrates were capable of sufficient
platelet increment even when stored for up to 5 days.
Received: 28 December 1995 / Accepted: 14 May 1996 相似文献
19.
Motor evoked potentials (MEPs) obtained by electrical root stimulation and F waves were used to examine the proximal nerve conduction velocity (CV) to tibialis anterior (TA), extensor digitorum brevis (EDB), flexor carpi radialis (FCR), and abductor pollicis brevis (APB) muscles in 40 humans. By subtracting motor latencies obtained by stimulating the peripheral nerve at the same point from the F-wave and MEP latencies, we could measure the CV over identical proximal segments. It was found that proximal CV to TA and FCR was significantly higher than to EDB and APB, respectively. Combining the data of the proximal CV to all four muscles in relation with axonal length resulted in a highly significant inverse relationship (r2 = 0.77). Thus the axonal length explained to a large extent the higher CV of the arm nerves and also the inverse relation between body height and CV. The distal CV was always lower than proximal CV; however, there was no support for an additional effect of this gradient in explaining the relationship between CV and height since it was constant for all body heights. © John Wiley & Sons, Inc. 相似文献
20.
Bavo Vanden Eynde Dirk Vienne Magda Vuylsteke-Wauters Dirk Van Gerven 《European journal of applied physiology》1988,57(4):430-434
Summary To determine the cardiorespiratory response to maximal exercise before, during and after the pubescent growth spurt, thirty boys were tested at yearly intervals over a period of six consecutive years. For each individual, peak height velocity (PHV) was determined. The age at PHV (¯X= 13.6 years) was taken as a standard of maturation. The results from all subjects at 1.5 and 0.5 years before and 0.5 and 1.5 years after PHV are presented. The highest oxygen uptake (
) obtained during an incremental bicycle ergometer test to voluntary exhaustion was taken as peak oxygen uptake (
peak). Across each of the four years studied, mean
peak (min=49.6; max=52.5 ml·kg–1·min–1) and mean heart rate (HR) at
peak (min=190; max=192) did not change significantly as a function of PHV. On the other hand, the respiratory quotient at
peak increased considerably from mean minima and maxima of 0.99 and 1.01 before PHV to 1.07 and 1.10 after PHV. Ventilatory equivalent for
(
), taken as an indicator of ventilatory economy, seemed to be unaffected by the maturation process. The steepest increase in circumpubertal oxygen pulse was found one year after PHV. Average stability coefficients (¯r), calculated from the inter-years correlations were high for height (¯r=0.95), weight (¯r=0.92), HR at
peak (¯r=0.74),
peak in 1/min (¯r=0.71), oxygen pulse (¯r=0.68) and tidal volume (¯r=0.64). 相似文献