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排序方式: 共有195条查询结果,搜索用时 11 毫秒
81.
Barwick RB Tillman MD Stopka CB Dipnarine K Delisle A Sayedul Huq M 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(6):1638-1643
Individuals with an intellectual disability (ID) have higher rates of obesity, lower rates of physical activity, cardiorespiratory fitness, and muscular endurance than do typically developed individuals (TDI) and are twice as likely to develop chronic disease, living half as long as TDIs do. The purpose of this study was to examine the improvements in physical capacity and functional ability in Special Olympic Athletes (SOAs) aged 19-22 years after participating in a functional training (FT) program and compare these scores with those of the SOAs in a resistance weight training (WT) program. Twenty SOAs (13 men, 7 women with mild to moderate ID) participated in a 1-hour FT program, twice a week, for 10 weeks, compared with 22 same-aged SOAs (14 men, 8 women) participating in a 1-hour WT program (2× week for 8 weeks). Prefitness and postfitness tests consisting of heart rate (HR) for the 3-minute step test, static plank, body weight squats, static bar hang, and knee push-ups were conducted. Two-tailed, paired sample t-tests (p < 0.05) were used to evaluate the differences in the FT group. Change scores were used to compare FTG with the WT group. The HR decreased by 31.8 b·min?1 pre-post in the FTG (p < 0.001). Static plank duration improved by 22.4 seconds in the FTG (p = 0.016); static plank change scores improved (p = 0.037) for the FTG (26.5 ± 32.1 seconds compared with that for the WT group (4.6 ± 22 seconds). Height and weight values were unchanged in both the groups. The results of this study demonstrate the value of FT programs for this population, because weight equipment is not always available in many settings. 相似文献
82.
Axillary clearance provides important prognostic information but is associated with significant morbidity. Sentinel node biopsy can provide staging .141 patients with node negative early breast cancers-tumour size less than 1.5 cm measured clinically or by imaging had guided axillary sampling (sentinel lymph node biopsy in combination with axillary sampling). Four node axillary sampling improved the detection rate of axillary node metastases by 13.6% as compared to blue dye sentinel node biopsy alone. Positive sampled nodes strongly indicated the likelihood of further metastatic being revealed by axillary dissection (67%). Negative sampled nodes in combination with a positive sentinel node biopsy were associated with a much lower rate of further nodal involvement in the axillary clearance (8%). 相似文献
83.
O-glycosylation is a post-translational protein modification that occurs in all eukaryotes. Yeasts have received increasing attention as a host for therapeutic protein production because of their ability to secrete high levels of recombinant protein. Because yeasts such as Pichia pastoris have been shown to O-glycosylate some proteins with varying effects on protein function, it is important to elucidate the nature of this modification. Methods that characterize O-glycosylation on a qualitative and quantitative basis are thus important when considering yeast as a host for therapeutic protein production. This protocol describes the release of O-glycans from a protein sample by -elimination under alkaline conditions using sodium borohydride and sodium hydroxide. The released O-linked oligosaccharides are subsequently processed and then separated by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD). An estimation of O-glycan molar occupancy and average O-mannose chain length is ultimately derived. This protocol requires approximately 3 d for completion. This method provides an assessment of O-glycosylation and allows one to correlate the effect of O-glycosylation on protein properties. 相似文献
84.
Intraspecific host discrimination and larval competition were studied forMicroplitis croceipes (Cresson),Microplitis demolitor Wilkinson,Cotesia kazak (Telenga), andHyposoter didymator (Thunberg), solitary endoparasitoids of the tobacco budworm,Heliothis virescens (F.). In ovipositional choice tests between unparasitized and parasitized hosts, the mean number of ovipositions for unparasitized
hosts was significantly higher than the mean number of ovipositions for hosts parasitized once by a conspecific female forC. kazak andH. didymator, demonstrating that females of these 2 species discriminate against hosts recently (within a few seconds) parasitized by
a conspecific female. No significant difference in oviposition occurred between these 2 kinds of hosts forM. croceipes andM. demolitor. Mean percent parasitization by a 2nd conspecific female was determined at 24, 48, and 72-h delays in time between the 1rst and 2nd female attack, and with no delay. Except for the 0 h time delay forC. kazak andH. didymator, percent parasitization by a 2nd conspecific female generally decreased as the delay in time between the 1rst and 2nd female attack increased. When the 2nd parasitization immediately followed the 1rst, one parasitoid larva always eliminated the other by physical combat. With a 24 or 48 h delay between the 1rst and 2nd parasitization, the younger larva was the victor over the older larva forM. croceipes, M. demolitor andC. kazak in at least 50% of the cases. Elimination of older larvae by younger larvae was by physical attack. However, forH. didymator, the older instar was the victor, and elimination of younger larvae by older larvae was probably through physiological processes.
Further, older larvae ofH. didymator apparently killed the eggs of the 2nd female by physiological processes.
相似文献
85.
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87.
Jeffrey Benovic Tommy Tillman Amelia Cudd Irwin Fridovich 《Archives of biochemistry and biophysics》1983,221(2):329-332
Both the iron-containing and the manganese-containing superoxide dismutases from Escherichia coli show diminished activity with increasing ionic strength, indicative of electrostatic facilitation of the catalyzed reaction. Since both enzymes bear a net negative charge at the assay pH, as does the substrate, this suggests a cationic locale in the active site region. Acetylation of the enzymes inverted their response to increasing ionic strength. It thus appears that lysine residues provide the observed electrostatic facilitation. A specific inhibition by large monovalent anions was observed with the iron-containing superoxide dismutase and was taken to indicate the presence of a cationic group, within a hydrophobic crevice, at the active site. 相似文献
88.
89.
V?Srinivasan GJM?Maestroni DP?Cardinali AI?Esquifino SR?Pandi?Perumal SC?MillerEmail author 《Immunity & ageing : I & A》2005,2(1):17
Aging is associated with a decline in immune function (immunosenescence), a situation known to correlate with increased incidence
of cancer, infectious and degenerative diseases. Innate, cellular and humoral immunity all exhibit increased deterioration
with age. A decrease in functional competence of individual natural killer (NK) cells is found with advancing age. Macrophages
and granulocytes show functional decline in aging as evidenced by their diminished phagocytic activity and impairment of superoxide
generation. There is also marked shift in cytokine profile as age advances, e.g., CD3+ and CD4+ cells decline in number whereas
CD8+ cells increase in elderly individuals. A decline in organ specific antibodies occurs causing reduced humoral responsiveness.
Circulating melatonin decreases with age and in recent years much interest has been focused on its immunomodulatory effect.
Melatonin stimulates the production of progenitor cells for granulocytes-macrophages. It also stimulates the production of
NK cells and CD4+ cells and inhibits CD8+ cells. The production and release of various cytokines from NK cells and T-helper
lymphocytes also are enhanced by melatonin. Melatonin presumably regulates immune function by acting on the immune-opioid
network, by affecting G protein-cAMP signal pathway and by regulating intracellular glutathione levels. Melatonin has the
potential therapeutic value to enhance immune function in aged individuals and in patients in an immunocompromised state. 相似文献
90.
MCWHINNIE MARY A.; CAHOON MARY ODILE SR.; JOHANNECK ROSEMARIE 《Integrative and comparative biology》1969,9(3):841-855
Cyclic shifts of calcium in the exoskeleton and soft tissues,as they are related to the intermolt cycle in crayfish, arereviewed. Regulatory factors, derived from the eyestalk, influencelevels of exoskeletal calcium; eyestalk extracts prepared fromanimals in premolt decrease shell calcium, while reciprocallyextracts from animals in intermolt increase it when these hormonalsources are injected into animals in the premolt stage (D0-D4). In addition, premolt eyestalk extract results in an increasein gastrolith calcium. In the exchange of calcium between theanimal and its environment there is evidence for differentialdepositionof recently available calcium in the exoskeleton. Further, intermoltand early premolt animals maintained in Ca45-labelled waterfor 15 days concentrate it 4 and 3fold in the exoskeletonand stomach, respectively. However, removal of a molt-inhibitingfactor through ablation of eyestalks results in a 20 and 40foldincrease in incorporation inthese same sites relative to environmentalconcentrations. Treatment with mammalian parathyroid extract mobilizes bothexoskeletal and gastric calciumand leads to a rise in bloodcalcium. However, there is little or no effect on levels ofexoskeletal citric acid. Further, citric acid is higher in thecrayfish carapace during stage C, the period of mineralization,than in stage D, the period of demineralization. There are both similarities and differences between the effectsof crustacean and mammalianregulating factors with respect tothe direction and extent of mineralization. Biochemical studiesshould elucidate the mechanisms regulated by these hormones. 相似文献