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81.
Serum hormones in male strength athletes during intensive short term strength training 总被引:1,自引:0,他引:1
Summary Training-induced adaptations in the endocrine system and strength development were investigated in nine male strength athletes during two separate 3-week intensive strength training periods. The overall amount of training in the periods was maintained at the same level. In both cases the training in the first 2 weeks was very intensive: this was followed by a 3rd week when the overall amount of training was greatly decreased. The two training periods differed only in that training period I included one daily session, while during the first 2 weeks of period II the same amount of training was divided between two daily sessions. In general, only slight and statistically insignificant changes occurred during training period I in mean concentrations of serum hormones examined or sex hormone-binding globulin as well as in maximal isometric leg extensor force. However, during training period II after 2 weeks of intensive strength training a significant decrease (P<0.05) was observed in serum free testosterone concentration [from 98.4 (SD 24.5) to 83.8 (SD 14.7) pmol · l–1] during the subsequent week of reduced training. No change in the concentration of total testosterone was observed. This training phase was also accompanied by significant increases (P<0.05) in serum luteinizing hormone (LH) and cortisol concentrations. After 2 successive days of rest serum free testosterone and LH returned to (P<0.05) their basal concentrations. Training period II led also to a significant increase (P<0.05) [from 3942 (SD 767) to 4151 (SD 926) N] in maximal force. These findings suggest that in male strength athletes dividing the amount of training into smaller units may create more effective training stimuli leading to further strength development. 相似文献
82.
Riitta Hari Ritva Hänninen Timo Mäkinen Veikko Jousmäki Nina Forss Mika Seppä Oili Salonen 《Neuroscience letters》1998,240(3):998-134
We describe patient E.P. who occasionally perceives a ‘ghost' hand which copies the previous positions of the left hand with a 0.5–1 min time lag, but follows the movement patterns of the right hand. The symptoms started after an operation of a ruptured aneurysm, followed by an infarction of the right frontal lobe; E.P. also has a previously lesioned corpus callosum. Neuromagnetic recordings revealed that activity of the left secondary somatosensory cortex was strongly suppressed during the ghost arm percept, thereby providing an objective correlate for E.P.'s sensations. We conclude that simultaneous mental contents about body scheme may be based on neural information extracted at considerably different times, resulting in fragmentation of bodily awareness. 相似文献
83.
A scheme of administration of nicotinic acid by mouth is suggested in order to prevent any increase in the free fatty acid concentration in the serum after intravenous injection of heparin or triiodothyronine, prolonged starvation, and thyroid feeding.Laboratory of Pathological Physiology, Institute of Experimental Endocrinology and Hormone Chemistry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Yudaev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 78, No. 8, pp. 122–125, August, 1974. 相似文献
84.
Alzheimer's disease (AD) includes a long asymptomatic stage, which precedes the formal diagnosis of dementia. AD biomarker models provide a framework for precision medicine approaches during this stage. However, such approaches have ignored the possible influence of sex on cognition and brain health, despite female sex noted as a major risk factor. Since AD-related changes may emerge in midlife, intervention efforts are being redirected around this period. Midlife coincides with several endocrinological changes, such as the menopausal transition experienced by women. In this narrative review, we discuss evidence for sex-differences in AD neuropathological burden and outline key endocrinological mechanisms for both sexes, focussing on hormonal events throughout the lifespan that may influence female susceptibility to AD neuropathology and dementia onset. We further consider common non-modifiable (genetic) and modifiable (lifestyle and health) risk factors, highlighting possible sex-dependent differential effects for the AD disease course. Finally, we evaluate the studies selected for this review demonstrating sex-differences in cognitive, pathological and health factors, summarising the state of sex differences in AD risk factors. We further provide recommendations for targeted research on female-specific risk factors, to inform personalised strategies for AD-prevention and the promotion of female brain health. 相似文献
85.
In order to determine whether the coselection observed between the selection trait (active avoidance behavior) of the Roman High Avoidance (RHA) and Roman Low Avoidance (RLA) rat lines and their neuroendocrine characteristics were genetically determined, we analyzed, in nonsegregating (RHA, RLA, and F1) and segregating (F2 and the two backcrosses) crosses, the inheritance pattern and the phenotypic correlations among behavioral (shuttle-box behavior), physiological (body, adrenal, and thymus weights), and neuroendocrine (corticosterone and prolactin reactivity, catecholamine enzyme activities) variables. Physiological characteristics and enzyme activities have acrucial role in sex dissociation. Avoidance behavior and prolactin reactivity to novel environment remained associated in segregating crosses despite gene rearrangement. They represented the most important variables to differentiate the Roman lines, perhaps sharing a common regulatory mechanism under genetic control. 相似文献
86.
N McClure J Leya E Radwanska R Rawlins R V Haning 《Human reproduction (Oxford, England)》1992,7(6):758-764
The incidence and statistical associations of the ovarian hyperstimulation syndrome (OHSS) were studied in 304 egg retrievals with gonadotrophin-releasing hormone agonist suppression, gonadotrophin administration and follicular aspiration. In addition to preserving corpus luteum function, the luteal phase administration of human chorionic gonadotrophin (HCG) was associated with a higher incidence of severe OHSS than was supplementation with progesterone alone (12 versus 0%, P less than 0.001). Severe OHSS occurred in 3.7% and 12% of retrievals without and with pregnancy respectively (P less than 0.01). Stepwise logistic regression showed that the occurrence of moderate or severe OHSS was statistically predicted by the log of the serum oestradiol on the day the initial HCG was given (P less than 0.0001), treatment with luteal phase HCG (P less than 0.0003), and fetal number (P less than 0.0079). In the late luteal phase of cycles without luteal HCG, the serum oestradiol concentration was one-tenth and the serum progesterone concentration was one-fifth of the luteal phase value with HCG support (P less than 0.001). Without luteal phase HCG, oestradiol was two-fold higher (P less than 0.001) and progesterone was 1.4-fold higher (P less than 0.005) in pregnant than in non-pregnant women. With luteal phase HCG, oestradiol was 1.4-fold higher in pregnant than in non-pregnant women (P less than 0.05), and progesterone was 1.7-fold higher (P less than 0.001). Oestradiol upper limits of 4400 and 14,700 pmol/l (1200 and 4000 pg/ml) for cycles with and without luteal phase HCG respectively correspond to approximately 5% risk of moderate or severe OHSS with a singleton pregnancy under these conditions. 相似文献
87.
Bang AK Carlsen E Holm M Petersen JH Skakkebaek NE Jørgensen N 《Human reproduction (Oxford, England)》2005,20(11):3109-3113
BACKGROUND: It has been suggested that finger length may correlate with function or disorders of the male reproductive system. This is based on the HOXA and HOXD genes' common embryological control of finger development and differentiation of the genital bud. The objective of this study was to explore the association between the ratio of 2nd to 4th finger length (2D:4D ratio) and testis function in a sample of young Danish men from the general population. METHODS: Semen samples and finger measurements were obtained from a total of 360 young Danish men in addition to blood samples for sex hormone analysis to describe the possible association between 2D:4D and semen and sex-hormone parameters. RESULTS: A statistically significant inverse association with the 2D:4D was found only in relation to hormone levels of FSH in the group of young men with a 2D:4D >1 (P = 0.036) and a direct association with the total sperm count in the group of young men with a 2D:4D < or = 1 (P = 0.045). CONCLUSION: The statistically significant results may be 'false positives' (type I error) rather than representing true associations. This relatively large study of young, normal Danish men shows no reliable association between 2D:4D finger ratio and testicular function. Measurements of finger lengths do not have the power to predict the testicular function of adult men. 相似文献
88.
Norma McCoy Ph.D. Winnifred Cutler Ph.D. Julian M. Davidson Ph.D. 《Archives of sexual behavior》1985,14(5):385-394
Forty-three perimenopausal women kept daily records of menstrual cycles and sexual activity. Data on hot flashes and plasma estradiol and testosterone levels were obtained at two points during the menopausal transition. The prospective data yielded a significant negative association between hot flash ratings and regularity of sexual intercourse at both time points. A significant negative correlation was found between estradiol (in the early part of the cycle) and hot flashes ratings at the first data point only, and positive correlations were found between hot flashes and ratio of testosterone to estradiol (T/E) at both. Frequency of sexual intercourse and level of plasma estradiol were higher, and T/E and hot flash ratings were lower in early perimenopausal women who were still having cycles at least once every 30 days, as compared with late perimenopausal women who were cycling less often. It was concluded that a close association exists between increasing irregularity of menstrual cycles, hot flashes, declining estradiol levels, and declining frequency of intercourse during the perimenopause. Causal relationships remain to be established.Supported by NIH Grant AG1437. 相似文献
89.
Albert J. Azzaro John Liccione John Luccil 《Naunyn-Schmiedeberg's archives of pharmacology》1987,336(2):133-138
Summary Changes in the formation of cyclic AMP following d-amphetamine (0.1 to 20 pmol/1) were examined in vitro in striatal slices of the rat. d-Amphetamine caused a doserelated increase in cyclic AMP content. This action of d-amphetamine was abolished by tissue pretreatment with reserpine (2.5 mg/kg, i.p.) and 3-iodotyrosine (1 mmol/1). By contrast, both clorgyline (0.1 pmol/l) and nomifensine (30 mol/l) enhanced the d-amphetamine-induced increase in cyclic AMP formation. In superfusion experiments, a strong correlation between endogenous dopamine and cyclic AMP release was observed before, during and after d-amphetamine exposure. Finally, Sch 23390 (10 mol/1) abolished while (–)sulpiride (10 mol/1) enhanced the amphetamine-induced increase in cyclic AMP content. These results suggest that d-amphetamine enhances the formation of cyclic AMP through the release of endogenous dopamine into the synapse where it can interact with both D-1 and D-2 dopamine receptors. These results provide direct evidence that the antagonistic properties of D-1 and D-2 receptors on cyclic AMP formation are apparent at striatal synapses during release of endogenous neuronal dopamine.Abbreviations DA
dopamine
- 5-HT
serotonin
- CAMP
cyclic AMP adenosine-3,5-cyclic monophosphate
Supported in part by the West Virginia University Medical Corporation and a grant from the Fraternal Order of Eagles. Some of the findings were presented at the Annual meeting of the Society for Neurosciences, Washington, DC (Azzaro and Liccione 1986)
Send offprint requests to A. J. Azzaro at the above address 相似文献
90.
K. Andersson K. Fuxe P. Eneroth L. F. Agnati A. Härfstrand 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(5):521-528
Summary The effects of acute continuous exposure to the smoke from 1–4 cigarettes have been studied in the male rat in terms of hypothalamic catecholamine levels and utilization as well as the secretion of anterior pituitary hormones. Catecholamine levels in discrete hypothalamic catecholamine nerve terminal systems were studied by quantitative histofluorimetry. Catecholamine utilization was studied by means of the tyrosine hydroxylase inhibition method using -methyl-(±)-p-tyrosine methyl ester. The serum hormone levels of adenohypophyseal hormones and of corticosterone were measured by the use of radioimmunoassay procedures. The results show that acute continuous exposure to unfiltered but not to filtered (Cambridge glass fibre filters) cigarette smoke leads to small but dose-dependent reductions of amine levels in most of the hypothalamic noradrenaline and dopamine nerve terminal system. These effects were associated with an enhancement of regional hypothalamic noradrenaline utilization but not of dopamine utilization in the median eminence. Furthermore, a reduction of TSH and prolactin serum levels was noted as well as increases in ACTH secretion. These results are partly different from those previously obtained with rats acutely exposed to intermittent unfiltered cigarrete smoke. This difference is suggested to be due to a temporary blockade of catecholamine release following acute continuous exposure to cigarette smoke.This work has been supported by a grant (1223) from the Council for Tobacco Research, New York, USA and by a grant from the Svenska Tobaks monopolet
Send offprint requests to K. Andersson at the above address 相似文献