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991.
992.
Blair T. Crewther Neil Potts Liam P. Kilduff Scott Drawer Christian J. Cook 《Journal of Science and Medicine in Sport》2018,21(3):312-316
Objectives
Evidence suggests that stress-induced changes in testosterone and cortisol are related to future competitive behaviours and team-sport outcomes. Therefore, we examined whether salivary testosterone and cortisol reactivity to a mid-week stress test can discriminate a match outcome in international rugby union competition.Design
Single group, quasi-experimental design with repeated measures.Method
Thirty-three male rugby players completed a standardised stress test three or four days before seven international matches. Stress testing involved seven minutes of shuttle runs (2 × 20 m), dispersed across one-minute stages with increasing speeds. Salivary testosterone and cortisol were measured in the morning, along with delta changes from morning to pre-test (Morn-PreΔ) and pre-test to post-test (Pre-PostΔ). Data were compared across wins (n = 3) and losses (n = 4).Results
The Morn-PreΔ in cortisol increased before winning and decreased prior to losing (p < 0.001), with a large effect size difference (d = 1.6, 90% CI 1.3–1.9). Testosterone decreased significantly across the same period, irrespective of the match outcome. The Morn-PreΔ in testosterone and cortisol, plus the Pre-PostΔ in testosterone, all predicted a match outcome (p ≤ 0.01). The final model showed good diagnostic accuracy (72%) with cortisol as the main contributor.Conclusions
The salivary testosterone and cortisol responses to mid-week testing showed an ability to discriminate a rugby match outcome over a limited number of games. The Morn-PreΔ in cortisol was the strongest diagnostic biomarker. This model may provide a unique format to assess team readiness or recovery between competitions, especially with the emergence of rapid hormonal testing. 相似文献993.
Blair T. Crewther David Hamilton Liam P. Kilduff Scott Drawer Christian J. Cook 《Journal of Science and Medicine in Sport》2018,21(5):453-456
Objectives
To investigate the effect of oral contraceptive (OC) use on salivary testosterone (sal-T) concentrations and performance-related statistics in international field hockey matches.Design
A cohort observational study with repeated measures.Methods
Twenty-three elite female athletes were monitored across four international field hockey matches over a nine-day period. Salivary T was assessed 45 min before each match and several match performance statistics were collated; load (i.e. ratings of perceived exertion × playing time), video-derived positive actions (PA) and negative actions (NA), plus coach and player ratings of performance. The sal-T and match performance profiles of OC (n = 7) and Non-OC (n = 16) players were compared and predictive relationships tested.Results
Pre-match sal-T concentrations were 35% higher in the Non-OC than the OC group (p = 0.001), representing a large effect size (ES) difference of 0.96. The OC and Non-OC groups did not differ on any performance statistic (p ≥ 0.348) with ES differences from ?0.22 to 0.11. Salivary T was positively related to the number of PA during match play (p = 0.017). Additional linkage between sal-T and NA emerged, but with opposing slopes (p = 0.008) in the OC (B = ?1.783, p = 0.030) and Non-OC (B = 0.692, p = 0.127) groups.Conclusions
OC usage by elite women athletes was accompanied by lower sal-T concentrations, but the performance outputs of the OC and Non-OC groups were similar. This suggests that the T differences had no impact on match performance. On an individual (population-averaged) level, sal-T was associated with PA and NA during these matches, though the response curves predicting NA differed for OC and Non-OC athletes. 相似文献994.
995.
C. W. Pinson W. C. Chapman J. K. Wright E. B. Hunter J. A. Awad D. S. Raiford J. L. Payne S. Geevarghese T. K. Blair D. H. Van Buren 《Transplant international》1998,11(1):S278-S283
We compared results using Neoral versus Sandimmune, each in combination with steroid and azathioprine immunosuppression, in primary liver transplantation recipients. There were 15 patients in each group with similar demographic distributions. Intravenous cyclosporine was stopped at 4.3 ± 1.9 days in the Neoral group vs 7.8 ± 4.9 days in the Sandimmune group (P < 0.025). Cyclosporine levels in the first 10 days were higher (mean 306 ng/ml vs 231 ng/ml) in the Neoral group than the Sandimmune group (P < 0.05). The Neoral dose was less than the Sandimmune dose (mean 5.5 ng/kg per day vs 7.9 ng/kg per day) to achieve these levels in that time period (P < 0.05). Two patients (13 %) experienced three episodes of biopsy-proven rejection in the Neoral group compared to nine patients (60 %) with 12 episodes of rejection in the Sandimmune group (P < 0.025). Incidences of neurological and renal complications were similar between the groups. Infections requiring treatment were also similar. Liver function, renal function, and marrow function, evaluated at days 7, 14, 21, 28, and 2, 4, 6, and 12 months post-transplant, were not different between the groups. In summary, shorter use of intravenous cyclosporine and quicker stabilization of trough cyclosporine levels was achieved with Neoral than with Sandimmune. In the early posttransplant period, higher levels with lower doses were achieved with Neoral than with Sandimmune. In our experience, the incidence of rejection was lower with Neoral than with Sandimmune. There were similar lengths of hospitalization, mortality, adverse events, retransplantation, and similar liver, renal, and marrow function up to 1 year posttransplantation. Because of this experience, we continued to use Neoral in a total of 59 primary liver transplant recipients. We have not used intravenous cyclosporine in the last 44 patients. Follow-up was a mean of 11.4 months, ranging from 1 to 27 months. The incidence of rejection was 24 % in these 59 patients compared to our historical experience of 70 % using Sandimmune. 相似文献
996.
997.
E L Blair E R Grund J D Reed D J Sanders G Sanger B Shaw 《The Journal of physiology》1975,253(2):493-504
Chloralose anaesthetized cats were prepared with fundic and antral pouches. Fundic mucosal blood flow was measured by the amidopyrine technique and serum gastrin was measured by radioimmunoassay. 2. Meat extract suspension in the pyloric antrum produced a highly significant sixfold increase in arterial serum gastrin concentration (P less than 0-001). 3. The mean ratio of the fundic mucosal blood flow to acid secretory responses (deltaMBF/deltaH+ ratio) of 0-142 +/- 0-026 (25) ml./muequiv H+, is very similar to the values previously published for exogenous gastrin stimulation. 4. Splanchnic nerve stimulation, during responses to meat extract stimulation, produced significant reductions in gastric acid secretion (P less than 0-025), fundic mucosal blood flow (P less than 0-02), Arterial serum gastrin concentration (P less than 0-01) And gastrin delivered to the mucosa (P less than 0-001). 5. In the 30 min period following the end of splanchnic nerve stimulation only arterial serum gastrin concentration remained significantly reduced. 相似文献
998.
Towards high resolution maps of the mouse and human genomes--a facility for ordering markers to 0.1 cM resolution 总被引:9,自引:7,他引:9
Breen Maria; Deakln Lisa; Macdonald Bernard; Miller Steve; Sibson Ross; Tarttelln Emma; Avner Philip; Bourgade Franck; Guenet Jean-Louis; Montagutelli Xavler; Polrier Christophe; Simon Dominique; Tailor Dillp; Bishop Martin; Kelly Maria; Rysavy Francis; Rastan Sohaila; Norris Dominic; Shepherd David; Abbott Cathy; Pllz Alison; Hodge Sarah; Jackson Ian; Boyd Yvonne; Blair Helen; Maslen Gareth; A.Todd John; W.Reed Peter; Stoye Jonathan; Ashworth Alan; McCarthy Linda; Cox Roger; Schalkwyk Leo; Lehrach Hans; Klose Joachim; Gangadharan Uma; Brown Steve 《Human molecular genetics》1994,3(4):621-627
982 progeny produced by a mouse Interspecific backcross betweenC57BL/6 and Mus spretus have been scored for at least 3 markerson each chromosome, completing an anchor map of 78 loci acrossthe mouse genome. The anchor mapping identifies all the availablerecomblnants in each interanchor Interval allowing access topanels of mice that can be used for the high resolution mappingof any chromosome region. The large number of progeny recoveredand scored from the Interspecific backcross allows us to resolvegenetically markers that lie on average 200 kb apart on mousechromosomes and within the cloning capacity of currently availableYAC libraries. EUCIB provides the first genetic mapping resourcespecifically designed for the high resolution mapping of allregions of the mouse genome and will underpin the global physicalmapping of the mouse genome. In addition, with the use of conservedsequences the facility is applicable to the high resolutioncomparative mapping of the mouse and human genomes. A new databasehas been implemented to support the computation of high resolutionand ordered genetic maps. 相似文献
999.
Serum aluminum levels and erythrocyte dihydropteridine reductase activity in patients on hemodialysis 总被引:1,自引:0,他引:1
P Altmann F Al-Salihi K Butter P Cutler J Blair R Leeming J Cunningham F Marsh 《The New England journal of medicine》1987,317(2):80-84
Aluminum intoxication due to aluminum-containing antacids or dialysate can cause encephalopathy in patients undergoing hemodialysis, but the biochemical mechanism has not been defined. The enzyme dihydropteridine reductase (DHPR) is essential for the maintenance of normal brain concentrations of tetrahydrobiopterin, which is itself required for the synthesis of specific neurotransmitters. This enzyme is also present in erythrocytes. We measured erythrocyte DHPR activity and concentrations of the biopterin derivatives of its substrate and of aluminum in 38 patients on hemodialysis who had no clinical evidence of encephalopathy. Serum aluminum levels ranged from 15 to 190 micrograms per liter (mean, 67.6 +/- 7.7) as compared with 4.9 +/- 0.99 micrograms per liter in normal subjects. DHPR activity was inversely related to the serum aluminum concentration (r = -0.61, P less than 0.001) and was less than the activity predicted from the hemoglobin concentration in these patients. Serum concentrations of biopterin derivatives were markedly elevated. Eighteen patients were given the aluminum-chelating agent deferoxamine in a single dose, after which DHPR activity doubled. These studies suggest that aluminum inhibits DHPR activity in erythrocytes and that aluminum chelation reverses this effect. Although we did not directly measure DHPR activity in the brains of dialysis patients without encephalopathy, we propose that the reduction in activity in erythrocytes may reflect a similar reduction in the brain. Our findings could help to explain the encephalopathy associated with aluminum intoxication. 相似文献
1000.
D C Blair 《Clinical microbiology reviews》1997,10(4):650-673
International travel has increased enormously in recent years. With the greater movement of people have come increased encounters with a wide variety of diseases: malaria, dengue, cholera, typhoid fever, Ebola virus, and many more. The need for greater scope, consistency, and knowledgeability in pretravel health care to meet these challenges has been met by the emergence of the discipline of travel medicine. Travelers are well advised to become informed of the risks they face and to take steps to minimize those risks. After reviewing a traveler's medical history and a detailed itinerary, a travel medicine practitioner can offer expert advice on behavioral modifications, immunizations, and chemoprophylaxis regimens which will increase the traveler's margin of safety. The issues most frequently addressed in a travel clinic include treatment of traveler's diarrhea, malaria chemoprophylaxis, and immunizations, for hepatitis A, typhoid fever, tetanus/diphtheria, influenza, pneumococcus, hepatitis B, polio, meningococcus, measles, mumps, rubella, varicella, and rabies. Pretravel consultation must consider the age and underlying health problems of the traveler, the nature of the trip (wilderness, jungle, rural, urban, resort, or cruise), the duration of travel, and the latest available information on the site in terms of disease outbreaks, terrorism, and natural calamities. 相似文献