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991.
992.
Summary This study examines and compares the hemodynamic and sympathoadrenal response to bicycle exercise in hypertensive subjects during two weeks' treatment with a cardio-selective (metoprolol) and nonselective (propranolol) beta-blocker. The increase in plasma norepinephrine and epinephrine concentration following exercise was augmented to a similar degree with each beta-blocker. Pre-exercise blood pressure and heart rate were similar for the two drugs. However immediately after exercise and particularly after resting for 20 min post exercise, diastolic blood pressure was lower during metoprolol treatment. Systolic blood pressure was also lower 20 min post exercise during metoprolol treatment. These observations indicate that cardio-selective beta-blockers offer advantages in blood pressure control during exercise through intact vascular 2-adrenoceptors opposing sympathetically mediated vasoconstriction.  相似文献   
993.
AIM: To compare an ultrasonic height measuring device (Gulliver) with mechanical stadiometry and the classical "book and tape measure" method. METHODS: Blinded duplicate measurements of height were made on each of 14 children by a pair of observers using a stadiometer (H) and Gulliver (G). Height was measured on a further 18 children by parents and an auxologist using Gulliver and the book and tape method (TM), and the results were compared with those obtained with a single stadiometry measurement. Finally, measurement of a rigid metal box was made on 10 occasions by the three methods. RESULTS: In the group of 14 children, the mean difference (range) in height (H minus G) was +2.8 cm (+0.5 to +4.55 cm), with H giving a systematically higher value in 276 of 280 individual measurements. In the group of 18 children, height by H was greater than by G or TM in 47 of 52 individual measurements. The mean (SD) height of the box by H (61.60 (0.07) cm) was greater than by G (60.96 (0.15) cm; p < 0.001) but not TM (61.4 (0.16) cm; p > 0.05). G and TM produced three times less reliable estimations of height than H, but with a large difference in cost, and there was evidence of systematic underrecording of height by 0.5 cm with G. CONCLUSIONS: Stadiometry is precise and reproducible, and can detect true changes in height over one month periods in mid-childhood, and should remain the standard way of observing growth. The book and tape method can produce clinically acceptable quarterly estimations of height that can be performed in the home.  相似文献   
994.
One hundred and seventy six children with severe mental retardation underwent a fundoplication for considerable gastro-oesophageal reflux. There were six 'early' (3%) deaths and five 'late' deaths. Major complications developed in 17 (10%) children whereas 86 (49%) had 'minor' complications. A revision operation was required in 27 patients. Overall 142 (81%) children achieved a good result. In spite of the high complication rate and the need for a secondary operation in 15% of the patients, the quality of life for these children and their parents and carers is greatly improved by antireflux surgery.  相似文献   
995.
Brainstem reflexes were examined in 23 children treated with thiopentone infusion and correlated with serum thiopentone concentrations. The results suggest that if all brainstem reflexes are lost with a serum thiopentone concentration less than 40 mg/l, it is unlikely to be due to the thiopentone alone. Other causes including brain death need to be considered.  相似文献   
996.

Background  

Cystic fibrosis is the most common fatal genetic disorder in the Caucasian population. Scoring systems for assessment of Cystic fibrosis disease severity have been used for almost 50 years, without being adapted to the milder phenotype of the disease in the 21st century. The aim of this current project is to develop a new scoring system using a database and employing various statistical tools. This study protocol reports the development of the statistical tools in order to create such a scoring system.  相似文献   
997.
998.
Male infertility: analysis of the markers and genes on the human Y chromosome   总被引:10,自引:6,他引:10  
The long arm of the human Y chromosome is required for male fertility. Deletions in three different regions can cause severe spermatogenic defects ranging from non-obstructive azoospermia to oligozoospermia. Use of intracytoplasmic sperm injection (ICSI) may allow Y chromosome defects to be passed from father to son. Thus, numerous reports have stressed the need to offer genetic testing to infertile men who select ICSI and a number of reproductive clinics have begun to do so. The primary objectives of this review were: firstly, to discuss the characteristics of the published set of polymerase chain reaction markers and how these characteristics affect interpretation of Y chromosome deletion analysis and secondly, to summarize the recent literature pertaining to the genes on the Y chromosome.   相似文献   
999.
1000.
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