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911.
Biological responses to overload training in endurance sports 总被引:2,自引:0,他引:2
Rod W. Fry Alan R. Morton Peter Garcia-Webb G P M Crawford David Keast 《European journal of applied physiology》1992,64(4):335-344
Summary Five subjects undertook 10 days of twice daily interval training sessions on a treadmill followed by 5 days of active recovery. On days 1, 6, 11, and 16 the subjects were required to undertake a test of submaximal and maximal work capacity on a treadmill combined with a performance test consisting of a run to exhaustion with the treadmill set at 18 km · h–1 and 1% gradient. Also on these days a pre-exercise blood sample was collected and analysed for a range of haematological, biochemical and immunological parameters. The subjects experienced a significant fall in performance on day 11 which had returned to pretraining levels on day 16. Serum ferritin concentrations were depressed significantly from pretraining concentrations at the conclusion of the recovery period while the expression of lymphocyte activation antigens (CD25+ and HLA-DR+) was increased both after the training phase and the recovery phase. The number of CD56+ cells in the peripheral circulation was depressed at the conclusion of the recovery period. Several parameters previously reported to change in association with overload training failing to reflect the decrease in performance experienced by subjects in this study, suggesting that overtraining may best be diagnosed through a multifactorial approach to the recognition of symptoms. The most important factor to consider may be a decrease in the level of performance following a regeneration period. The magnitude of this decreased performance necessary for the diagnosis of overtraining and the nature of an appropriate regeneration period are, however, difficult to define and may vary depending upon the training background of the subjects and the nature of the preceding training. It may or may not be associated with biochemical, haematological, physiological and immunological indicators. Individual cases may present a different range of symptoms and diagnosis of overtraining should not be excluded based on the failure of blood parameters to demonstrate variation. However, blood parameters may be useful to identify possible aetiology in each separate case report of overtraining. An outstanding factor to emerge from this study was the difficulty associated with an objective diagnosis of overtraining and this is a possible reason why there have been new accounts of overtraining research in the literature. 相似文献
912.
David V. Gauvin Bradley D. Youngblood Frank A. Holloway 《Alcoholism, clinical and experimental research》1992,16(2):336-341
Twenty male Sprague-Dawley rats were trained to discriminate pentylenetetrazole (PTZ, 15 mg/kg, intraperitoneally) from saline (SAL) under a drug discrimination procedure. Test sessions were conducted with 10 randomly selected subjects. Tests with various doses of PTZ resulted in a dose-dependent increase in the percentage of total session responses emitted on the PTZ-appropriate lever without a significant change in response rates across a wide range of test PTZ doses. Rats did not generalize the PTZ stimulus to ethanol (ETOH) up to ETOH test doses that completely suppressed responding. High acute ETOH doses (2, 3, and 4 g/kg) administered at various time points prior to discrimination test sessions engendered responding on the PTZ-appropriate level in a quantitative fashion, that was dose- and time-dependent. This acute ETOH delayed effect from these high doses replicates our previously published study using a Drug 1-Drug 2 discrimination task with Chlordiazepoxide and PTZ. More importantly, we suggest that the present behavioral assay may be a sensitive animal analogue of human "hangover" phenomena. 相似文献
913.
M. Stephen Murphy M.R.C.P. David Gardner-Medwin M.D. M.R.C.P. Edmund J. Eastham M.R.C.P. 《The American journal of gastroenterology》1989,84(10):1329-1330
Achalasia of the cardia, a disorder associated with degenerative loss of esophageal myenteric ganglion cells, is reported in association with a recently described progressive neurological disorder, "early onset cerebellar ataxia with retained reflexes." This form of cerebellar ataxia is thought to be inherited as an autosomal recessive disorder. The occurrence of these two very rare neurodegenerative disorders in a single individual is of interest because of the potential genetic and pathogenetic implications of the association. 相似文献
914.
Late luteal phase dysphoric disorder and DSM-III-R 总被引:1,自引:0,他引:1
R L Spitzer S K Severino J B Williams B L Parry 《The American journal of psychiatry》1989,146(7):892-897
Text and diagnostic criteria for a new category, late luteal phase dysphoric disorder, appear in appendix A of DSM-III-R: "Proposed Diagnostic Categories Needing Further Study." The inclusion of this category in the manual was perhaps the most controversial aspect of the revision of DSM-III. In this paper the authors describe the work of the advisory committee that first proposed the category, the rationale for the category's inclusion in the manual, and the many issues that were the focus of heated debates. 相似文献
915.
David de Wied Jan M. van Ree 《European archives of psychiatry and clinical neuroscience》1989,238(5-6):323-331
Summary Animal studies have demonstrated that neuropeptides modulate nervous system functions. It has been postulated that disturbances in neuropeptide systems may be aetiological factors in psychiatric and neurological disorders. Neuropeptides related to ACTH/MSH, including ORG 2766, increase motivation and attention and facilitate recovery processes after nerve damage. These peptides may be effective during the early stage of dementia. Vasopressin and related peptides improve memory processes in animals and humans. In addition, these peptides influence social behaviour, mood and addictive behaviour. The non-opioid -type endorphins have neurolepticlike activities in animals and antipsychotic effects in a category of schizophrenic patients. Peptides related to CCK have also been found to be effective in these patients. Some neuropeptides, e.g. TRH and PLG, have been reported to exert antidepressant effects. Further research may eventually produce neuropeptides with therapeutic action in psychiatric and neurological diseases.Parts of this article were presented on the occasion of the inauguration ceremony of the Department of Psychiatry of the University of Mainz on April 2 and 3, 1987 相似文献
916.
V Vilgrain J Frija C Yana L J Couderc M David J P Clauvel M Laval-Jeantet 《Journal de radiologie》1989,70(3):167-173
Three patients with lymphoid interstitial pneumonia (two HIV 1+ patients with chronic lymphadenopathic syndromes and one with a not-characterized autoimmune disease) have been studied with high-resolution computed tomography (HR-CT). This technique reveals septal lines, small reticulonodular opacities, polyhedral micronodular opacities, "ground-glass" opacities and a dense, subpleural, curved broken line in one patient. The lesions dominate in the bases of the lungs. They are not characteristic for lymphoid interstitial pneumonia. If a patient present with a chronic lymphadenopathic syndrome, the diagnosis of an opportunistic infection should not be automatically made, since the syndrome can be caused by lymphoid interstitial pneumonia. 相似文献
917.
A sacral ulcer is described where ischaemia due to a vascular "steal" syndrome in the gluteal angiotome was the cause of persistent failure of flap reconstruction. Thrombotic obliteration of the abdominal aorta had resulted in the development of collaterals which, paradoxically, deprived the flaps based on standard angiotomes of their major source of blood supply, as they became the major source of perfusion for the legs. Healing of the ulcer was successfully achieved only after aorto-iliac reconstruction. Two other cases of ischaemic sacral ulceration, associated with aortic occlusion, are described. 相似文献
918.
Mario Feola Jan Simoni David Fishman Rue Tran Peter C. Canizaro 《Artificial organs》1989,13(3):209-215
Hemoglobin (Hb) solutions can cause vasoconstriction and activation of intravascular coagulation. Because the endothelium plays a major role in the regulation of vascular tone and hemostasis, a study was conducted of human umbilical vein endothelial cells (EC) incubated with various Hbs. Cell injury was evaluated by electron microscopy and the release of lactic dehydrogenase, H2O2, and procoagulant "tissue factor." Cell reaction was assessed by the measurement of 6-keto-prostaglandin F (PGF)1 alpha (metabolite of prostacyclin) and thromboxane B2 (metabolite of thromboxane A2). Incubation with unmodified bovine hemoglobin for 24 h caused no cell injury and a reaction characterized by 48.4 +/- 8.2% increase in 6-keto-PGF1 alpha production, accompanied by 40.2 +/- 9.4% reduction in thromboxane (Tx)B2 (compared with a control group of EC incubated with saline solution). Incubation with a nonpure Hb solution (Hb plus red blood cell membrane aminophospholipids; a-PLs) caused cell injury with significant release of tissue factor, plus a reaction characterized by 97.5 +/- 12.5% increase in TxB2 production accompanied by 25.3 +/- 3% reduction in 6-keto-PGF1 alpha. A second nonpure Hb [Hb plus bacterial environmental endotoxin (E)] caused cell injury, the release of tissue factor, and increased production of both prostaglandins, with greater release of TxB2 (197 +/- 17%) than of 6-keto-PGF1 alpha (112 +/- 8.3%). These data indicate that the endothelium reacts differently to pure and nonpure hemoglobins. The biocompatibility of Hb solutions, with regard to vasoconstriction and activation of intravascular coagulation, depends on the absence of stromal a-PLs and bacterial E. 相似文献
919.
This is a retrospective study of the outcome of surgical procedures in patients who were Jehovah's Witnesses. Over a 75-month period, 58 Jehovah's Witness patients had 78 surgical procedures at the Vancouver General Hospital. Three patients had preexisting anaemia of less than 100 g.L-1 haemoglobin. Postoperative haemoglobin concentration decreased below 50 g.L-1 in three patients. One patient had a postoperative haemoglobin of 34 g.L-1 (haematocrit 10.1 per cent) and survived. One patient died from uncontrollable postoperative haemorrhage. Perioperative morbidity was not uncommon, including significant hypotension (eight cases), cardiac arrhythmias (six), myocardial ischaemia (three), excessive bleeding (four), postoperative nausea or syncope (four), and wound or urinary tract infection (four). 相似文献
920.
The Susan Britton Wills Unit at the Bristol General Hospital is a small and busy multidisciplinary psychiatric unit, providing a wide range of in-patient, out-patient and day-patient services for the residents of Bristol Health District.