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排序方式: 共有385条查询结果,搜索用时 31 毫秒
81.
Bread wheat varieties as influenced by different nitrogen levels 总被引:4,自引:2,他引:2
INTRODUCTION Dera Ismail Khan lies in Pakistan’s arid zone (71.07° longitude, 31.57° latitude and 500 m above sea level). This zone is in the extreme south of (NWFP) Pakistan at the bank of the River Indus. Dera Ismail Khan is bounded by Sulaiman Range to the West, the Indus River on the East, Marwat and Bhit- tani Ranges on the North and Vehowa Nala (Punjab) on the South. Besides certain local variability the area is comprised of four basic divisions viz mountains, a series … 相似文献
82.
Kasum M Oreskovic S Zec I Jezek D Tomic V Gall V Adzic G 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2012,22(2):171-179
Hypersecretion of prolactin by lactotroph cells of the anterior pituitary may lead to hyperprolactinemia in physiological, pathological and idiopathic conditions. Most patients with idiopathic hyperprolactinemia may have radiologically undetected microprolactinomas, but some may present other causes of hyperprolactinemia described as macroprolactinemia. This condition corresponds to the predominance of higher molecular mass prolactin forms (big-big prolactin, MW > 150 kDa), that have been postulated to represent prolactin monomer complexed with anti-prolactin immunoglobulins or autoantibodies. The prevalence of macroprolactinemia in hyperprolactinemic populations between 15-46% has been reported. In the pathophysiology of macroprolactinemia it seems that pituitary prolactin has antigenicity, leading to the production of anti-prolactin autoantibodies, and these antibodies reduce prolactin bioactivity and delay prolactin clearance. Antibody-bound prolactin is big enough to be confined to vascular spaces, and therefore macroprolactinemia develops due to the delayed clearance of prolactin rather than increased production. Although the clinical symptoms are less frequent in macroprolactinemic patients, they could not be differentiated from true hyperprolactinemic patients, on the basis of clinical features alone. Although gel filtration chromatography (GFC) is known to be the gold standard for detecting macroprolactin, the polyethylene glycol precipitation (PEG) method has offered a simple, cheap, and highly suitable alternative. In conclusion, macroprolactinemia can be considered a benign condition with low incidence of clinical symptoms and therefore hormonal and imaging investigations as well as medical or surgical treatment and prolonged follow-up are not necessary. 相似文献
83.
Headrick J Davids K Renshaw I Araújo D Passos P Fernandes O 《Journal of sports sciences》2012,30(3):247-253
The aim of this study was to determine whether spatiotemporal interactions between footballers and the ball in 1 vs. 1 sub-phases are influenced by their proximity to the goal area. Twelve participants (age 15.3 ± 0.5 years) performed as attackers and defenders in 1 vs. 1 dyads across three field positions: (a) attacking the goal, (b) in midfield, and (c) advancing away from the goal area. In each position, the dribbler was required to move beyond an immediate defender with the ball towards the opposition goal. Interactions of attacker-defender dyads were filmed with player and ball displacement trajectories digitized using manual tracking software. One-way repeated measures analysis of variance was used to examine differences in mean defender-to-ball distance after this value had stabilized. Maximum attacker-to-ball distance was also compared as a function of proximity-to-goal. Significant differences were observed for defender-to-ball distance between locations (a) and (c) at the moment when the defender-to-ball distance had stabilized (a: 1.69 ± 0.64 m; c: 1.15 ± 0.59 m; P < 0.05). Findings indicate that proximity-to-goal influenced the performance of players, particularly when attacking or advancing away from goal areas, providing implications for training design in football. In this study, the task constraints of football revealed subtly different player interactions than observed in previous studies of dyadic systems in basketball and rugby union. 相似文献
84.
Scafoglieri A Tresignie J Provyn S Marfell-Jones M Reilly T Bautmans I Clarys JP 《Journal of sports sciences》2012,30(8):777-785
The aim of the present study was to develop and cross-validate anthropometrical prediction equations for segmental lean tissue mass (SLM). One hundred and seventeen young healthy Caucasians (67 men and 50 women; mean age: 31.9 ± 10.0 years; Body Mass Index: 24.3 ± 3.2 kg · m(-2)) were included. Body mass (BM), stretch stature (SS), 14 circumferences (CC), 13 skinfolds (SF) and 4 bone breadths (BB) were used as anthropometric measurements. Segmental lean mass of both arms, trunk and both legs were measured by dual energy X-ray absorptiometry as the criterion method. Three prediction equations for SLM were developed as follows: arms = 40.394(BM) + 169.836(CCarm-tensed) + 399.162(CCwrist) - 85.414(SFtriceps) - 39.790(SFbiceps) - 7289.190, where Adj.R (2) = 0.97, P < 0.001, and standard error of estimate (SEE) = 355 g;trunk = 181.530(BM) + 155.037(SS) + 534.818(CCneck) + 175.638(CCchest) - 88.359(SFchest) - 147.232(SFsupraspinale) - 46522.165, where Adj.R(2) = 0.97, P < 0.001, and SEE = 1077g; and legs = 55.838(BM) + 88.356(SS) + 235.579(CCmid-thigh) + 278.595(CCcalf) + 288.984(CCankle) - 84.954(SFfront-thigh) - 53.009(SFmedial calf) - 28522.241, where Adj.R (2) = 0.96, P < 0.001, and SEE = 724 g. Cross-validation statistics showed no significant differences (P < 0.05) between observed and predicted SLM. Root mean squared errors were smallest for arms (362 g), followed by legs (820 g) and trunk (1477 g). These new prediction equations allow an accurate estimation of segmental lean mass in groups of young adults, but estimation errors of 8 to 14% can occur in certain individuals. 相似文献
85.
86.
The purpose of this study was twofold: (a) to examine the stressors experienced by injured athletes during three phases of their recovery from sport injury, and (b) to explore the differences in the stressors experienced by team as compared to individual-sport athletes. Participants comprised previously injured high-level rugby union players (n = 5) and golfers (n = 5). Semi-structured interviews were used to explore the stressors participants experienced during three phases of injury (onset, rehabilitation and return to competitive sport). Within- and cross-case analyses showed that athletes experienced sport, medical/physical, social and financial stressors. There were a number of differences in the stressors experienced across the three phases and between team and individual-sport athletes. Findings have important implications for the design and implementation of interventions aimed at managing the potentially stressful sport injury experience and facilitating injured athletes' return to competitive sport. 相似文献
87.
88.
In December 2006, the Australian Parliament liberalized regulation governing stem cell research. This decision and preceding legislative review generated considerable public debate, which centred on objections to the deliberate creation and destruction of human embryos for research purposes. This paper draws on qualitative research conducted on the public debate surrounding this policy episode. The aim of this research was to examine how science and scientific knowledge are mobilized by participants in these debates to support their arguments. Data were collected from 109 newspaper opinion editorials as well as 23 in-depth interviews and examined using qualitative content and thematic analysis. Results of this analysis depict science as a rhetorical, moral and political resource that provides opportunities for participants to gain legitimacy, negotiate meaning and assert authority in the public domain. The mobilization of science in public discourse is discussed along with suggestions that are aimed at encouraging greater transparency and inclusiveness in public debates around contested science and emergent technologies. 相似文献
89.
Storbeck C Martin D Parkin I Magongwa L Druchen BP Batchelor M McIlroy G De Villiers D Captieux-Bhana N Rasebopye L Rasebopye D Krige-Henderson S Krige F Louw A Surtees T Smit AL Cox R Henderson M 《American annals of the deaf》2010,155(4):488-518
In a special section of the american Annals of the Deaf, Deaf education and the Deaf community in South Africa are discussed. The special section is organized into 7 segments: a historical overview to establish context, the educational context, educators and learners, postgraduate education and employment, perspectives of Deaf children and their parents, sport and the arts, and spiritual lives and mental health. Throughout the entire section, however, the central focus is on the overall foundation (or lack thereof) of education for Deaf learners in South Africa. 相似文献
90.
Acute impact of submaximal resistance exercise on immunological and hormonal parameters in young men 总被引:2,自引:0,他引:2
In this study, we examined the acute effects of submaximal resistance exercise on immunological and hormonal parameters in 7 resistance-trained and 10 non-resistance-trained males. The participants, who were aged 29.5 +/- 7.1 years (mean +/- s), performed submaximal resistance exercise at 75% of their one-repetition maximum. Blood samples were taken before, during, immediately after, and 30, 60 and 120 min after exercise and analysed for leukocyte subpopulations and stress hormones. Total leukocytes, neutrophils and monocytes increased during exercise, reaching their maximum 2 h after exercise. Lymphocytes increased during exercise, T-helper cells returned to resting values after exercise, and natural killer cells and T-suppressor cells decreased below resting values. The CD4/CD8 ratio decreased during exercise but increased during recovery. The resistance-trained participants tended to have lower T-helper cell counts before, during and immediately after exercise and a lower CD4/CD8 ratio during recovery than the non-resistance-trained participants. Plasma cortisol correlated positively with leukocytes during exercise (r = 0.572, P < 0.05), but negatively with T-helper cells 30 and 60 min after exercise (r = -0.573, P < 0.05; r = -0.642, P < 0.01, respectively). Our results indicate that resistance exercise leads to acute changes in leukocyte counts, despite moderate hormonal changes, independent of training status. Regular resistance exercise might lead to decreased T-helper cell counts and a lower CD4/CD8 ratio, which could increase susceptibility to infections. 相似文献