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排序方式: 共有112条查询结果,搜索用时 18 毫秒
1.
2.
Papantoniou E Hammond EW Tsiami AA Scriven F Gordon MH Schofield JD 《Journal of agricultural and food chemistry》2003,51(4):1057-1063
Fractionation and reconstitution techniques were used to study the contribution of endogenous flour lipids to the quality of semisweet (Rich Tea-type) biscuits. Biscuit flour was defatted with chloroform and baked with bakery fat but without endogenous lipid addition. Semisweet biscuits baked from defatted flour were flatter, denser, and harder and showed collapse of gas cells during baking when compared with control biscuits. Defatted flour semisweet doughs exhibited a different rheological behavior from the control samples showing higher storage and loss moduli (G' and G' ' values), that is, high viscoelasticity. Functionality was restored when total nonstarch flour lipids were added back to defatted flour. Both the polar and nonpolar lipid fractions had positive effects in restoring flour quality, but the polar lipid fraction was of greatest benefit. Both fractions were needed for complete restoration of both biscuit quality and dough rheological characteristics. 相似文献
3.
Equine anaesthesia is associated with a high risk of perioperative morbidity and mortality, particularly in the recovery period. Cardiovascular collapse and cardiopulmonary arrest (CPA) have been reported to account for one-third of anaesthesia-related perioperative deaths in the horse. This case report describes the successful cardiopulmonary resuscitation of a healthy adult Thoroughbred mare that developed cardiovascular collapse and subsequent CPA following positioning in the recovery box after general anaesthesia in the Trendelenburg position. Cardiopulmonary resuscitation (CPR) was instigated and included thoracic compressions, intermittent positive pressure ventilation and adrenaline administered via the intravenous and intra-tracheal routes. Return of spontaneous circulation (ROSC) was detected 5 min and 50 s after the start of CPR. A stable stance was achieved approximately 100 min after ROSC. The mare was discharged from the hospital 3 days later with no known complications. To the authors’ knowledge, this is the first case report documenting CPA following general anaesthesia in the Trendelenburg position in a horse, with subsequent successful CPR. The precise cause of the CPA is unknown but a number of plausible hypothesis are discussed including hypoventilation and a Bezold-Jarisch reflex. 相似文献
4.
- Tracking of juvenile sea turtles is a research priority to inform the protection of relevant habitats and ensure sustainable rates of recruitment into adult populations. Based on satellite tracking, mixed stock analysis, and mark–recapture studies, Drini Bay in the South Adriatic Sea, Central Mediterranean, has been confirmed as an important foraging site used by loggerhead turtles from all major rookeries in the Mediterranean subpopulation.
- Three juvenile loggerhead turtles (Caretta caretta) from Drini Bay were tracked for 763, 364, and 211 days respectively. All turtles exhibited different movement patterns.
- The two smaller turtles ranged widely beyond the bay. One of these (69.5 cm curved‐carapace length; CCL) used the coldest region of the Mediterranean during the first winter of tracking where mean weekly temperatures dipped below 12°C but moved southwards to warmer waters during the second winter. In comparison, the other (66 cm CCL) individual moved south to winter in warmer waters from the outset. Both individuals returned to Drini Bay during summer, demonstrating fidelity to the study site. The third turtle, which was larger (76 cm CCL), remained in Drini Bay for the duration of tracking. These results support the findings of other mark–recapture studies at Drini Bay, which have suggested that the foraging site is being used in a transient way by immature turtles.
- All three turtles preferentially used the shallow waters (<30 m) in the south of Drini Bay. The study demonstrates a high degree of overlap between the habitat use of the three tracked turtles and that of adult turtles tracked from nesting sites, and although based on a small sample size, contributes to a growing knowledge base regarding the wider habitat use of the Mediterranean loggerhead population.
5.
Eileen K. Schofield 《Biological conservation》1973,5(1):48-51
A wide variety of cultivated plants has been introduced to the Galápagos Islands since settlements were first established there in the 1830s. Through poor management, many of these plants have escaped to the wild and are taking over extensive areas of native forest. Two endemic species, Scalesia pedunculata Hook.f. and Miconia robinsoniana Cogn., are especially endangered by farming practices. Some measures for the control and use of cultivated plants must be enforced to save the Galápagos flora from further damage. 相似文献
6.
An important consequence of acidification is the mobilization of Al from the edaphic to the aquatic environment. Elevated Al levels in acidic waters may be toxic to fish. Eggs, larvae, and postlarvae of white suckers (Catostomus commersoni) and brook trout (Salvelinus fontinalis) were exposed in laboratory bioassays to pH levels 4.2 to 5.6 and inorganic Al concentrations of 0 to 0.5 mg l?1. Aluminum toxicity varied with both pH and life history stage. At low pH levels (4.2 to 4.8), the presence of Al (up 0.2 mg l?1 for white suckers; 0.5 mg l?1 for brook trout) was beneficial to egg survival through the eyed stage. In contrast, Al concentrations of 0.1 mg l?1 (for white suckers) or 0.2 mg l?1 (for brook trout) and greater resulted in measurable reductions in survival and growth of larvae and postlarvae at all pH levels (4.2 to 5.6). Aluminum was most toxic in over-saturated solutions at pH levels 5.2 to 5.4. The simultaneous increase in Al concentration with elevated acidity must be considered to accurately assess the potential effect of acidification of surface waters on survival of fish populations. 相似文献
7.
Jason?J.?Z.?LiaoEmail author Timothy?L.?Schofield Philip?S.?Bennett 《Journal of Agricultural, Biological & Environmental Statistics》2005,10(2):148-157
A house standard lot is tested along with experimental samples in a variable TCID50 assay in order to monitor and control assay performance. Instead of being simply a control, it is proposed to use this lot
as a calibration standard to reduce the systematic variability in the assay caused by acknowledged sources of variability
such as the age of the cells used in the assay and interlaboratory differences. Because of this new proposal, the consistency
of the relationship between the test sample and the house standard is assessed within the acceptance range of the house standard.
A linear mixed-effects measurement error model is proposed for the data. The slope curve is then used to assess the dynamic
relationship between the sample and the house standard within the house standard range. It is shown with these analyses that
the sample and the house standard have uniformly good agreement within the house standard range. 相似文献
8.
Formation of virus-like particles by bone cells in mice with a high incidence of spontaneous leukemia 总被引:2,自引:0,他引:2
B H Schofield C P Barrett S B Doty F H Figge R A Robinson 《Science (New York, N.Y.)》1970,168(931):588-589
Bone samples from potentially leukemic and leukemic mice revealed numerous 90-to 110-nanometer particles morphologically identical to murine leukemia virus. Particles were observed budding from plasma membranes of osteocytes and osteoblasts but were most numerous in osteocyte lacunae. Particles were not observed in bone samples from mice which rarely develop leukemia. 相似文献
9.
Taylor FW Diner DJ Elson LS McCleese DJ Martonchik JV Delderfield J Bradley SP Schofield JT Gille JC Coffey MT 《Science (New York, N.Y.)》1979,205(4401):65-67
Further results from the Venus orbiter radiometric temperature experiment (VORTEX) on the Pioneer orbiter are presented. These are used to characterize the three-dimensional temperature field, the cloud structure, and the dynamics of the 60-to 130-kilometer altitude region of the Venus atmosphere. One of the new discoveries is a "dipole" structure at high latitudes, with two hot spots rotating around the pole, surrounded by banks of cold cloud. 相似文献
10.
Pham KN Puertas AM Bergenholtz J Egelhaaf SU Moussaïd A Pusey PN Schofield AB Cates ME Fuchs M Poon WC 《Science (New York, N.Y.)》2002,296(5565):104-106
Experiments, theory, and simulation were used to study glass formation in a simple model system composed of hard spheres with short-range attraction ("sticky hard spheres"). The experiments, using well-characterized colloids, revealed a reentrant glass transition line. Mode-coupling theory calculations and molecular dynamics simulations suggest that the reentrance is due to the existence of two qualitatively different glassy states: one dominated by repulsion (with structural arrest due to caging) and the other by attraction (with structural arrest due to bonding). This picture is consistent with a study of the particle dynamics in the colloid using dynamic light scattering. 相似文献