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991.
The objective of the study was to examine salivary biomarker response to fluid consumption in exercising athletes. Exercise induces stress on the body and salivary alpha amylase (sAA) and salivary cortisol are useful biomarkers for activity in the sympathoadrenal medullary system and the hypothalamic pituitary adrenal axis which are involved in the stress response. Fifteen college students were given 150 ml and 500 ml of water on different days and blinded to fluid condition. The exercise protocol was identical for both fluid conditions using absolute exercise intensities ranging from moderate to high. Saliva was collected prior to exercise, post moderate and post high intensities and analyzed by Salimetrics assays. Exercise was significant for sAA with values different between pre-exercise (85 ± 10 U · ml−1) and high intensity (284 ± 30 U · ml−1) as well as between moderate intensity (204 ± 32 U · ml−1) and high intensity. There was no difference in sAA values between fluid conditions at either intensity. Exercise intensity and fluid condition were each significant for cortisol. Cortisol values were different between pre-exercise (0.30 ± 0.03 ug · dL−1) and high intensity (0.45 ± 0.05 ug · dL−1) as well as between moderate intensity (0.33 ± 0.04 ug · dL−1) and high intensity. Moderate exercise intensity cortisol was lower in the 500 ml condition (0.33 ± 0.03 ug · dL−1) compared with the 150 ml condition (0.38 ± 0.03 ug · dL−1). This altered physiological response due to fluid consumption could influence sport performance and should be considered. In addition, future sport and exercise studies should control for fluid consumption.  相似文献   
992.
Based on their activity in patients with advanced stage chronic lymphocytic leukemia (CLL), a phase I/II study was designed to evaluate the feasibility, safety, and efficacy of autologous vaccines made from oxidized tumor cells in patients with earlier stage CLL, and to determine an optimal schedule of injections. Eighteen patients (at risk for disease progression and with white blood cell counts between 15 and 100×106 cells/ml) were injected intramuscularly with 10 ml of oxidized autologous blood (composed mainly of CLL cells) either 12 times over 6 weeks (group 1), 12 times over 16 days (group 2), or 4 times over 6 weeks (group 3). Fourteen out of eighteen patients had Rai stage 0–II disease, while 4/18 had stage III–IV disease but did not require conventional treatment. Partial clinical responses, associated with enhanced anti-tumor T cell activity in vitro, were observed in 5/18 patients of whom three were in group 2. Stable disease was observed in six patients while disease progression appeared not to be affected in the remaining patients. Toxicity was minimal. Vaccination with oxidized autologous tumor cells appears worthy of further investigation and may be a potential alternative to a watch and wait strategy for selected CLL patients.  相似文献   
993.
Many models of sex-biased dispersal predict that the direction of sex-bias depends upon a species' mating system. In agreement with this, almost all polygynous mammals show male-biased dispersal whereas largely monogamous birds show female-biased dispersal (FBD). The hamadryas baboon (Papio hamadryas hamadryas) is polygynous and so dispersal is predicted to be male biased, as is found in all other baboon subspecies, but there are conflicting field data showing both female and male dispersal. Using 19 autosomal genetic markers genotyped in baboons from four Saudi Arabian populations, we found strong evidence for FBD in post-dispersal adults but not, as expected, in pre-dispersal infants and young juveniles, when we compared male and female: population structure (F(st)), inbreeding (F(is)), relatedness (r), and the mean assignment index (mAIc). Furthermore, we found evidence for female-biased gene flow as population genetic structure (F(st)), was about four times higher for the paternally inherited Y, than for either autosomal markers or for maternally inherited mtDNA. These results contradict the direction of sex-bias predicted by the mating system and show that FBD has evolved recently from an ancestral state of male-biased dispersal. We suggest that the cost-benefit balance of dispersal to males and females is tightly linked to the unique hierarchical social structure of hamadryas baboons and that dispersal and social organization have coevolved.  相似文献   
994.
Enzyme-linked immunosorbent assays for acetylcholinesterase (AChE) and for butyrylcholinesterase (BuChE) were markedly more specific than conventional assays using selective enzyme inhibitors. The new assays were used with blood and brain samples containing traces of one enzyme dominated by large amounts of the other. The results showed that human plasma does contain AChE (8 ng/ml), even though its major cholinesterase is BuChE (3,300 ng/ml). BuChE immunoreactivity was not detected in human red blood cells but occurred in all brain regions. The cerebellum was the richest region tested (540 ng of BuChE/g of tissue), whereas the cerebral cortex was the poorest (240 ng of BuChE/g). However, because of the small local AChE content (99 ng/g), BuChE was the major cortical cholinesterase. The picture was reversed in the putamen, where BuChE immunoreactivity (340 ng/g) was far outweighed by that of AChE (6,100 ng/g).  相似文献   
995.
The inner ear of adult agnathan vertebrates is relatively symmetric about the anteroposterior axis, with only two semicircular canals and a single sensory macula. This contrasts with the highly asymmetric gnathostome arrangement of three canals and several separate maculae. Symmetric ears can be obtained experimentally in gnathostomes in several ways, including by manipulation of zebrafish Hedgehog signalling, and it has been suggested that these phenotypes might represent an atavistic condition. We have found, however, that the symmetry of the adult lamprey inner ear is not reflected in its early development; the lamprey otic vesicle is highly asymmetric about the anteroposterior axis, both morphologically and molecularly, and bears a striking resemblance to the zebrafish otic vesicle. The single sensory macula originates as two foci of hair cells, and later shows regions of homology to the zebrafish utricular and saccular maculae. It is likely, therefore, that the last common ancestor of lampreys and gnathostomes already had well-defined otic anteroposterior asymmetries. Both lamprey and zebrafish otic vesicles express a target of Hedgehog signalling, patched, indicating that both are responsive to Hedgehog signalling. One significant distinction between agnathans and gnathostomes, however, is the acquisition of otic Otx1 expression in the gnathostome lineage. We show that Otx1 knockdown in zebrafish, as in Otx1(-/-) mice, gives rise to lamprey-like inner ears. The role of Otx1 in the gnathostome ear is therefore highly conserved; otic Otx1 expression is likely to account not only for the gain of a third semicircular canal and crista in gnathostomes, but also for the separation of the zones of the single macula into distinct regions.  相似文献   
996.
Due to the abnormal vasculature of solid tumors, tumor cell oxygenation can change rapidly with the opening and closing of blood vessels, leading to the activation of both hypoxic response pathways and oxidative stress pathways upon reoxygenation. Here, we report that ataxia telangiectasia mutated-dependent phosphorylation and activation of Chk2 occur in the absence of DNA damage during hypoxia and are maintained during reoxygenation in response to DNA damage. Our studies involving oxidative damage show that Chk2 is required for G2 arrest. Following exposure to both hypoxia and reoxygenation, Chk2-/- cells exhibit an attenuated G2 arrest, increased apoptosis, reduced clonogenic survival, and deficient phosphorylation of downstream targets. These studies indicate that the combination of hypoxia and reoxygenation results in a G2 checkpoint response that is dependent on the tumor suppressor Chk2 and that this checkpoint response is essential for tumor cell adaptation to changes that result from the cycling nature of hypoxia and reoxygenation found in solid tumors.  相似文献   
997.
998.
The development of 2-phenylbenzoxazoles as inhibitors of cholesteryl ester transfer protein (CETP) is described. Initial efforts aimed at engineering replacements for the aniline substructures in the benchmark molecule. Reversing the connectivity of the central aniline lead to a new class of 2-(4-carbonylphenyl)benzoxazoles. Structure-activity studies at the C-7 and terminal pyridine ring allowed for the optimization of potency and HDLc-raising efficacy in this new class of inhibitors. These efforts lead to the discovery of benzoxazole 11v, which raised HDLc by 24 mg/dl in our transgenic mouse PD model.  相似文献   
999.
1000.

Objective

Children with Down syndrome, the most common genetic cause of intellectual disability, are prone to multiple and varied health-related problems. This study describes patterns of hospitalisations for children and young people with Down syndrome in Western Australia.

Methods

Birth records were linked to the Western Australian population-based Intellectual Disability database to identify all children born with Down syndrome in Western Australia between 1 January, 1983 and 31 December, 1999. These records were linked to the Hospital Morbidity Data System to provide information on all hospitalisations up to 31 December, 2004. Hospitalisation data, coded using ICD-9CM or ICD-10 (v0.5) were grouped into clinically relevant categories using the primary diagnosis. Rates of hospital admission for all and specific diagnoses were expressed in 1000-person-years at-risk and median age at first admission and length of stay were calculated.

Results

Of the 405 children, 395 had one or more hospital admissions, totalling 3786 admissions for all children and an estimated 39.5 person-years in hospital. On average, children were admitted 9.7 times, with an estimated rate of 757.2 admissions per 1000pyr (95% CI: 680, 843). A quarter of all admissions occurred in the first year of life. The average hospital length of stay was 3.8 days (95% CI: 3.7, 4.1). Upper respiratory tract conditions affected the most children (58.5%) and accounted for 12.1% of all admissions. Other disorders which affected a high percentage of children were ear/hearing conditions (50.6%), disorders of the oral cavity (38.0%) and lower respiratory tract conditions (37.5%). Overall, children with Down syndrome were hospitalised at a rate five times (95% CI = 4.3–6.2) that of the general population.

Conclusion

Children with Down syndrome are at increased risk of morbidity for varied causes underlining the importance of comprehensive and targeted primary care for this group.  相似文献   
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