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1.
A previous study showed that adult female dancers have a high percentage of type I fibres in vastus lateralis. similar to that of endurance-trained female runners ar female cross-country skiers. It is not known if dancers already at an early age are characterized by a high percentage of type I fibres or develop a high percentage of type I fibres as a consequence of dance training. Furthermore. the muscle fibre composition of male dancers has not previously been studied. Therefore the aim of the study was to analyse skeletal muscle fibre characteristics in 10-year-old and 20-year-old dancers of both sexes. Age-matched boys and girls whose physical activity was average for their age groups served as controls. Muscle biopsies for histochemical analysis were obtained from vastus lateralis using the percutaneous needle technique. The major finding of the present study was that the vastus lateralis of young dancers of both sexes had a higher percentage of type I fibres than that of controls. Moreover. the higher type I percentage was seen not only in 20 year aids. but also in 10 year aids. who had begun their dance training at a professional level only a few weeks earlier. No significant difference in this respect was found between female and male dancers. In conclusion. the muscle fibre type composition in young dancers of both sexes differs from that of the average individual of the same age and is characterized by a high percentage of type I fibres.  相似文献   
2.
The contractile and relaxant effects of various prostanoids were studied on isolated human pial arteries. Contractions were elicited with the following order of potency: U46619?U44069>PGB2>PGF2a>PGE2?PGD2>PGF1a≥TXB2, indicating that prostanoid-induced contractions probably are mediated by a thromboxane-sensitive receptor. Relaxation of PGF2a-contracted arteries was induced with the order of potency: PGE2> PGE1>PGD2?PGD1. Vessels contrated by K+ were relaxed only by PGE,. Since PGI2 was previously found to be more potent than all the prostanoids tested in the present study, relaxant responses are probably mediated via a PGI2-sensitive receptor. The roles of free extracellular and cellularly bound calcium for the contractile effects of PGF2a and K+ were estimated by incubating the arteries for various times in calcium-free medium containing 10-5 M EGTA. Incubation for 5–10 min abolished K+-induced contractions, whereas after 40 min of incubation PGF2a still induced contractions that reached 70% of control. The PGF2a-induced contraction was biphasic in 8 out of 10 preparations. The second phase could be eliminated by increasing the EGTA-concentration to 10-4 M, as well as by nifedipine pretreatment. In calcium-free, high K+ medium calcium-induced contractions were elicited at lower concentrations in the presence of PGF2a. The results suggest that PGF2a-induced contractions in human pial arteries are relatively independent of free extracellular calcium. PGF2a may promote trans-membrane influx of calcium, as well as release calcium from seemingly superficially located cellular stores.  相似文献   
3.
The influence of thoracic extradural local anaesthetics (0.5%bupivacaine) or extradural morphine on the metabolic responseto upper abdominal surgery was compared with the administrationof morphine i.v. in the period after operation. The extradurallocal anaesthetic group had significantly lower blood glucoseand plasma FFA concentrations and consistently, but not significantly,lower blood glycerol and lactate concentrations than both theother groups. At 4 h both extradural groups had significantlylower plasma FFA and blood 3-hydroxybutyrate concentrationsthan the control group. Blood alanine concentration decreasedin all three groups with a minimum at 24 h. There were no differencesin serum insulin concentrations between the groups. It is concludedthat thoracic extradural morphine differs from thoracic extradurallocal anaesthetics in being much less able to suppress the metabolicresponse associated with upper abdominal surgery.  相似文献   
4.
Mothers' beliefs and evaluations of their child's illness werestudied in a group of 30 mothers who had con sulted a generalpractitioner because of a cough. Data were collected by tape-recordedsemi-structured interviews conducted in their own homes. A majorconcern for mothers was their fear that their child was goingto die, usually because of choking on phlegm or vomit, but alsothrough an asthma attack or cot death. Mothers were also worriedthat their child would develop long-term chest damage. Particularlyimportant in mothers' assessments were their experience of disturbedsleep because of worries about their child dying at night andtheir belief that the cough was ‘on the chest’ whichgave rise to worries about dying through choking on phlegm andlong-term chest damage. Antibiotics were commonly believed tobe required to break up phlegm which might cause the long-termdamage or the choking and death.  相似文献   
5.
A highly sensitive method for the determination of morphine in plasma and brain samples down to 500 pg ml-1 in plasma and 100 pg in 30 mg of brain tissue is described. This sensitivity is in the range of that described for radioactive and radioimmunological tehcniques. The samples (50-500 mu-l) are extracted with toluene-butanol (9:1) at pH 8.9 and then re-extracted into 0.1 N sulphuric acid and back extracted to a toluene-butanol phase at pH 8.9. The pentafluoropropionic anhydride derivatives of morphine and the internal standard nalorphine were quantitatively determined by gas-liquid chromatography with a 3-H electron capture detector.  相似文献   
6.
ABSTRACT In a retrospective study over a 20-year period we found in the Umeå region in Sweden 11 patients (7 women and 4 men, mean age 67 years) with both hepatocellular carcinoma and acute intermittent porphyria. This coincidence was highly significant. Concomitant existence of portal cirrhosis of the liver was demonstrated in those 5 patients in whom it could be examined.  相似文献   
7.
Abstract— The aim of the study was to measure the fluoride release from glass ionomer based liners/bases after storing the specimens for 24 h and for 6 months in running water. The fluoride release was greater in the beginning than after half a year. From most liner materials the initial and the long-term release was greater than from the glass ionomer filling material studied for comparison. From two liners the release was minimal, just at the detection limit.  相似文献   
8.
ABSTRACT A simple and practical provocative test is needed for early asymptomatic pheochromocytoma, which is a major risk for patients with multiple endocrine neoplasia type 2 (MEN-2). We measured plasma catecholamines before and after submaximal exercise in 26 MEN-2 gene carriers, eight of whom with asymptomatic pheochromocytoma, nine with medullary thyroid carcinoma and 10 after uni- or bilateral adrenalectomy. Seventeen clinically healthy individuals and 11 patients with neurovegetative lability and symptoms mimicking pheochromocytoma served as controls. Plasma adrenaline, noradrenaline and dopamine increased after excercise except for adrenaline after bilateral adrenalectomy. The post-exercise levels of adrenaline and the adrenalineldopamine ratio were significantly higher in the pheochromocytoma patients compared to the healthy controls and the patients with neurovegetative lability, while the patients with medullary thyroid carcinoma represented an intermediate group with a high probability of developing adrenal tumors. The present method is a physiological test with a high sensitivity and specificity. It is practical and well suited for repeated examinations and seems to be of value for the detection of early pheochromocytoma in MEN-2 patients. Furthermore, the test could be used in the differential diagnosis between pheochromocytoma and neurovegetative lability.  相似文献   
9.
Hallander HO, Andersson M, Gustafsson L, Ljungman M, Netterlid E. Seroprevalence of pertussis antitoxin (anti‐PT) in Sweden before and 10 years after the introduction of a universal childhood pertussis vaccination program. APMIS 2009; 117: 912–22. The prevalence of IgG ELISA antibodies against pertussis toxin (anti‐PT) was studied in two Swedish seroepidemiological studies. One was performed in 1997 when the new pertussis vaccination program was 1 year old (n = 3420). In 2007, when Pa vaccines had been used countrywide for 10 years in the universal child vaccination program, this study was repeated to analyze the effect of vaccination on anti‐PT prevalence (n = 2379). Before the statistical analysis of seroprevalence, children vaccinated within the last 2 years before the serosurveys were excluded. The results indicate a reduced exposure to Bordetella pertussis in the population. The proportion of sera without measurable anti‐PT antibodies increased significantly, aggregated over all comparable age groups, from 3.8% in people sampled in 1997 to 16.3% in people sampled in 2007. For cord blood, 1% was without measurable anti‐PT antibodies in 1997 compared to a significantly higher level, 12%, in 2007. With anti‐PT concentrations of ≥50 and ≥100 EU/ml as cutoff points for ‘recent infection’ the proportion above the cutoff points for younger children was significantly higher in 1997 than in 2007 at both cutoff points. For all adults, 20 years of age and older, the difference in proportions above the lower cutoff point was close to statistically significant, comparing 1997 with 2007. This was not the case at 100 EU/ml. In the 1997 samples of children, there was a significant downward trend of ‘recent infections’ at both cutoff points for three sampled age groups between 5 and 15 years of age from 21% at 5.0–5.5 years of age to 7% at 14.7–15.7 years for the lowest cutoff. In the 2007 samples of children, on the contrary, there was a significant continuous upward trend of ‘recent infections’, at both cutoff points, for four sampled age groups between 4 and 18 years of age – from 4% at 4–5 years of age to 16% at 17–18 years at the lowest cutoff. The continuous increase, with age of children with high anti‐PT concentrations, supports the recent change in the general Swedish childhood vaccination program to include a pre‐school booster at 5–6 years and a school‐leaving booster at 14–16 years of age.  相似文献   
10.
ABSTRACT The antihypertensive effects of verapamil over 24 hours were assessed on twice and thrice daily dose regimens on 12 patients (25–65 years of age; mean age 50) with essential hypertension (WHO stages I–II) in a randomised, double-blind, cross-over trial. After a dose titration period starting with either verapamil 80 mg tid or 120 mg bid the patients kept their maintenance dose (240, 360 or 480 mg daily) for 4 weeks before crossing over to the other administration schedule. Repeated ambulatory blood pressure (BP) curves were recorded in 10 patients with a non-invasive portable device (Pressurometer III, Del Mar Avionics). The BP reductions (causal BP values) obtained by 2- and 3-dose regimens were of similar magnitude (from 170±19/105±8 on placebo to 140±17/87±7 and to 146±14/88±8 by 2- and 3-dose respectively). Analyses of BP curves revealed close similarity in profiles on the two dose regimens, although DBP was significantly (p<0.05) lower by 3-dose as compared to 2-dose regimen during the period 0.00–2.59 a.m. Long-term (circadian rhythm) and short-term variability did not differ between the regimens. Despite the slight difference in DBP curves after midnight, the overall impression is that verapamil given both twice and thrice daily provides adequate BP control throughout 24 hours.  相似文献   
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