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181.
OBJECTIVE: To assess the prevalence of zinc inadequacy based on dietary intakes and plasma zinc concentrations and, simultaneously, the prevalence of inadequate intakes of energy, protein, calcium and iron. DESIGN: A cross-sectional study of a convenience sample of subsistence farming households in Sidama, Southern Ethiopia. SUBJECTS: Dietary intakes were calculated from 1-day weighed food records and 40 repeats from 99 pregnant women in the third trimester using analysed values of major staple foods for zinc, iron, calcium and phytate. The distribution of observed intakes was adjusted for usual intakes and the prevalence of inadequacy estimated using the estimated average requirement (EAR) cutpoint method. Prevalence of inadequacy for zinc, protein and iron intakes were compared with those based on biochemical measures. RESULTS: Prevalence of zinc inadequacy was very high: 99% for US FNB EAR and 100% for IZiNCG EAR compared to 72% based on low plasma zinc concentrations. Corresponding prevalence estimates for iron were much lower: 4% for inadequate intakes based on US FNB EAR vs. 8.7% for iron deficiency anaemia (haemoglobin < 110 g l-1; ferritin < 12 microg l-1) and 32.3% for low storage iron. Prevalence of inadequacy for protein was 100% for adjusted intakes and 91% for serum albumin < 32 g l-1. For calcium, 74% were at risk for inadequate intakes. CONCLUSION: The high prevalence of inadequate intakes of zinc and protein was reasonably consistent with those based on biochemical measures. Such dietary deficits could be overcome by regular consumption of cellular animal protein. In contrast, both dietary and biochemical measures of iron inadequacy were low.  相似文献   
182.
文章作者详细分析工程量清单计价的意义、概念、作用及基本特征,并提出应注意的问题。  相似文献   
183.
184.
The National Aeronautics and Space Administration Goddard Space Flight Center-University of Delaware Bartol Research Institute magnetic field experiment on the Voyager 2 spacecraft discovered a strong and complex intrinsic magnetic field of Neptune and an associated magnetosphere and magnetic tail. The detached bow shock wave in the supersonic solar wind flow was detected upstream at 34.9 Neptune radii (R(N)), and the magnetopause boundary was tentatively identified at 26.5 R(N) near the planet-sun line (1 R(N) = 24,765 kilometers). A maximum magnetic field of nearly 10,000 nanoteslas (1 nanotesla = 10(-5) gauss) was observed near closest approach, at a distance of 1.18 R(N). The planetary magnetic field between 4 and 15 R(N) can be well represented by an offset tilted magnetic dipole (OTD), displaced from the center of Neptune by the surprisingly large amount of 0.55 R(N) and inclined by 47 degrees with respect to the rotation axis. The OTD dipole moment is 0.133 gauss-R(N)(3). Within 4 R(N), the magnetic field representation must include localized sources or higher order magnetic multipoles, or both, which are not yet well determined. The obliquity of Neptune and the phase of its rotation at encounter combined serendipitously so that the spacecraft entered the magnetosphere at a time when the polar cusp region was directed almost precisely sunward. As the spacecraft exited the magnetosphere, the magnetic tail appeared to be monopolar, and no crossings of an imbedded magnetic field reversal or plasma neutral sheet were observed. The auroral zones are most likely located far from the rotation poles and may have a complicated geometry. The rings and all the known moons of Neptune are imbedded deep inside the magnetosphere, except for Nereid, which is outside when sunward of the planet. The radiation belts will have a complex structure owing to the absorption of energetic particles by the moons and rings of Neptune and losses associated with the significant changes in the diurnally varying magnetosphere configuration. In an astrophysical context, the magnetic field of Neptune, like that of Uranus, may be described as that of an "oblique" rotator.  相似文献   
185.
介绍了利用各种栽培架和新型栽培基质,进行菜秧、小株型青菜无土栽培技术要点,以为苏南地区小白菜的多样栽培提供参考。  相似文献   
186.
An in vitro model of the feline blood-brain barrier was developed using primary cultures of brain capillary endothelial cells derived from adult cats. They were grown in the presence of astrocytes obtained from newborn kittens. Feline endothelial cell cultures were characterised by uptake of DiI-acetylated low-density lipoprotein (DiI-Ac-LDL) and expression of von Willebrand factor. Astrocytes were characterised based on their expression of glial fibrillary acidic protein (GFAP). Electron microscopy revealed junctional specialisation between endothelial cells. Occludin and ZO-1 expression by the endothelial cell cultures was detected by Western blot analysis. Barrier function of co-cultured endothelial cells and astrocytes was confirmed by a transendothelial electrical resistance (TEER) value of 30-35 Omegacm2 and apparent permeability coefficients (Papp) for FD-40 (FITC-dextran, 40 kDa) of 4x10(-6) cm/s and for FD-4 (4kDa) of 1.92x10(-5) cm/s. In endothelial cell monolayers grown with astrocyte-conditioned medium, the TEER value was lower (20-25 Omegacm2), and Papp of FD-40 and FD-4 was higher at 6.27x10(-6) and 3.96x10(-5) cm/s, respectively. This model should have useful applications in the examination of events occurring at the BBB early in FIV infection, and may provide knowledge applicable to HIV infection.  相似文献   
187.
ObjectiveTo explore, in rabbits, the minimum infusion rates (MIR) required and recovery time from long duration (≤8 hours) continuous infusion of fospropofol disodium, a novel water-soluble prodrug of propofol, and compare it with propofol.Study designProspective, randomized, blinded experimental trial.AnimalsNinety-six adult laboratory rabbits, mean ± SD weight 2.20 ± 0.15 kg.MethodsStage 1. 16 rabbits were assigned to receive fospropofol disodium or propofol to measure MIR, using an up-and-down method with response to tail-clamping stimulus (TCS). Stage 2. Eighty rabbits were allocated to group F (fospropofol disodium) or group P (propofol), and further subdivided (n = 10 in each subgroup) according to infusion time (2, 4, 6 or 8 hours), to groups F2h, F4h, F6h, F8h and P2h, P4h, P6h, P8h. Fospropofol or propofol were infused, and tail clamping applied to maintain the same depth of anaesthesia until infusion was completed. Times to recover righting reflex (RR), to respond to TCS, and total recovery to different durations of continuous infusion of two anaesthetic drugs were noted. Respiratory and pulse rates and oxygen saturation were analyzed. The plasma concentrations of fospropofol disodium, the active metabolite propofol (propofolF) and propofol emulsion were measured with respect to loss and recovery of RR and TCS.ResultsMIR of fospropofol disodium was 2.0 mg kg?1 minute?1, and MIR of propofol was 0.9 mg kg?1 minute?1. Times in minutes to total recovery from anaesthesia in groups F and P were as follows, F2h 15 ± 3; F4h 26 ± 4; F6h 52 ± 6; F8h 84 ± 10; and P2h 10 ± 1; P4h 19 ± 7; P6h 36 ± 7; P8h 48 ± 5.Conclusions and clinical relevanceAfter continuous intravenous infusion in rabbits (≤8 hours), fospropofol disodium and propofol both show an extension of recovery time with increasing infusion time, fospropofol disodium showing a significantly greater prolongation compared to propofol emulsion when infusion time increases to 6 and 8 hours.  相似文献   
188.
Efficacy of ammonium tetrathiomolybdate (3.4 mg/kg LW, TTM(3.4)) was monitored in nine, specific pathogen-free sheep with mild-to-severe, prehaemolytic copper poisoning (pre-HCP). Five sheep were given three subcutaneous injections over seven days and four began a shorter, five-day course four days later. Plasma bile acid (BA) and glutamate dehydrogenase (GDH) had fallen significantly after six days but BA briefly rose again between days 10 to 18. Aspartate aminotransferase (AST), δ-glutamyl transferase (GGT) were later to decline but presented little evidence of hepatotoxicity by day 45. Erythrocyte superoxide dismutase (ESOD) was rapidly inhibited, activities falling by 65 per cent within three days and taking 25 days to recover. Trichloroacetic (TCA)-insoluble copper increased by 6 to 8 μmol/l after three days but had largely disappeared by day 18. Six lambs had become hypercupraemic by day 18 due to a rise in TCA-soluble Cu. ESOD activity fell again by 188±29.5 U/gHb between days 25 and 45 but had largely recovered by day 62. TTM(3.4) gave better control of hepatotoxicity than TTM(1.7) had done in more severely affects cohorts but at the expense of greater inhibition of ESOD. Treatment of pre-HCuP should rely more on reducing copper absorption until more is known of the side effects of TTM on cuproenzymes.  相似文献   
189.
Recreational hunting of indigenous wild artiodactyls has been one of the most lucrative and rapidly growing industries in Western Spain over the last five years. In the absence of careful ecological management, one consequence of the commercial exploitation of this natural resource has been the appearance of outbreaks of infectious disease; most notably bovine tuberculosis. From the outset of the study in 1997, we have observed a steady increase in prevalence of Mycobacterium bovis (M. bovis) in both species reaching 1.74 (+/-0.17) in deer in 2002 and 2.32 (+/-0.24) in wild boar. The latter species seems to be most severely affected with pulmonary lesions appearing more chronic than those observed in deer. In this study, we describe the epidemiology of M. bovis in European wild boar (Sus scrofa) and Iberian red deer (Cervus elaphus hispanicus) in Extremadura (W. Spain); a region where there are large areas of natural habitat for these species.  相似文献   
190.
The aim of this study was to investigate veterinary surgeons' perceptions, knowledge and use of animal physiotherapy in the Republic of Ireland. A questionnaire was developed and sent to 200 veterinary surgeons, of which 97 were returned. Results indicated that 77 (79%) of respondents were aware of animal physiotherapists. Common sources of information included veterinary colleagues, owners and professional journals, with physiotherapists themselves and undergraduate training being less commonly cited. Awareness of animal physiotherapy was greatest amongst those working in equine practice (χ2 = 5.7, df 1, p = 0.017); they were more knowledgeable about its techniques (t = 2.806, df 75, p = 0.006) and more likely to refer (χ2 = 48.36, df 1, p = 0.0001). Seventy-four respondents (96%) thought that more research was necessary to increase the evidence base for animal physiotherapy. If this branch of physiotherapy is to develop, there needs to be increased interaction and co-operation between veterinary surgeons and chartered animal physiotherapists.  相似文献   
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