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991.
Mary Carver Nico Blüthgen Judy F Grimshaw Glenn A Bellis 《Australian Journal of Entomology》2003,42(2):109-113
Abstract Aphis clerodendri Matsumura is newly recorded from Australia and is known from the Northern Territory, on islands in Torres Strait, and in rainforest in northern Queensland and New South Wales. It induces the formation of leaf pseudogalls on native species of Clerodendrum and is commonly attended by ants, which penetrate and may polydomously nest in the galls. Previously known only from eastern Asia, A. clerodendri can now be classified as native to Australia and Australasian in natural distribution. The species is also newly recorded from Papua New Guinea and Vietnam. 相似文献
992.
John F LaDisa Douglas A Hettrick Lars E Olson Ismail Guler Eric R Gross Tobias T Kress Judy R Kersten David C Warltier Paul S Pagel 《Journal of applied physiology》2002,93(6):1939-1946
Coronary stents improve resting blood flow and flow reserve in the presence of stenoses, but the impact of these devices on fluid dynamics during profound vasodilation is largely unknown. We tested the hypothesis that stent implantation affects adenosine-induced alterations in coronary hemodynamics and wall shear stress in anesthetized dogs (n = 6) instrumented for measurement of left anterior descending coronary artery (LAD) blood flow, velocity, diameter, and radius of curvature. Indexes of fluid dynamics and shear stress were determined before and after placement of a slotted-tube stent in the absence and presence of an adenosine infusion (1.0 mg/min). Adenosine increased blood flow, Reynolds (Re) and Dean numbers (De), and regional and oscillatory shear stress concomitant with reductions in LAD vascular resistance and segmental compliance before stent implantation. Increases in LAD blood flow, Re, De, and indexes of shear stress were observed after stent deployment (P < 0.05). Stent implantation reduced LAD segmental compliance to zero and potentiated increases in segmental and coronary vascular resistance during adenosine. Adenosine-induced increases in coronary blood flow and reserve, Re, De, and regional and oscillatory shear stress were attenuated after the stent was implanted. The results indicate that stent implantation blunts alterations in fluid dynamics during coronary vasodilation in vivo. 相似文献
993.
Judy A. Sullivan R. Jack Schultz 《Evolution; international journal of organic evolution》1986,40(1):152-158
Skewed sex ratios are common among several species of Poeciliopsis, a viviparous fish from northwestern Mexico. Since previous, unrelated studies from this laboratory (Angus and Schultz, 1983) suggested that deviation from a 1:1 sex ratio might be influenced by temperature, two inbred strains of P. lucida were tested for temperature-dependent sex determination by comparing sex ratios of offspring from pregnant females held at different water temperatures. Different sex ratios were produced by the two strains at the same temperature: one strain produced almost all-male offspring at 30°C and female-biased sex ratios at 24°C, while the other strain produced a 1:1 sex ratio at both temperatures. At intermediate temperatures, the labile strain produced sequentially fewer males with decreasing temperatures. The other strain produced a consistent sex ratio regardless of temperature. Poeciliopsis lucida apparently has a genetic polymorphism for temperature-influenced sex determination. An hypothesis is offered for the evolutionary origin of environmental sex determination. 相似文献
994.
Models are presented showing that, under certain conditions, when multiple offspring are reared simultaneously, the magnitude of offspring selfishness is independent of offspring-offspring genetic relatedness. When the cost (θ) of the selfish offspring's behavior approaches zero, alleles causing offspring selfishness spread as long as is positive.In general, simultaneous offspring are predicted to behave more selfishly than sequential offspring.Stable equilibria between alleles for selfish and non-selfish behavior are predicted for certain selfish alleles. 相似文献
995.
Abstract The first Australian records of mango shield scale ( Milviscutulus mangiferae ) from north Queensland and additional records from parts of Papua New Guinea are presented. The majority of specimens were collected from mango leaves ( Mangifera indica ). A summary of its known distribution, other hosts, identification and damage levels is also presented. Also, the detection of rice mealybug ( Brevennia rehi ) in far north Queensland is reported for the first time. This pest is known to occur in the Northern Territory. The north Queensland detections are from native grasses. The records presented here, for both species, are regarded as new detections, rather than new incursions. 相似文献
996.
In animals that produce few offspring during their lifetime, the ability to raise high-quality offspring through the provision of parental care is particularly important for individual fitness. In this paper, we use repeatability analysis of data from two separate time-periods, in the 1970s and the 1990s, to examine parental and environmental effects on chick growth and food provisioning in a long-lived seabird, the Manx shearwater Puffinus puffinus . We test the hypothesis that asymptotic body masses of chicks are most strongly influenced by an individual's genotype, with growth rates intermediate and food provisioning rates most strongly affected by environmental conditions during growth. Peak body masses of chicks raised by the same parents showed significant repeatability in both samples, whereas mass growth rates up to the attainment of peak mass showed significant repeatability only in the 1970s. Several different measures of food provisioning by parents showed no individual consistency in either time-period, in keeping with our predictions. Food provisioning rate was a major determinant of annual variation in chick growth, and so it may seem surprising that Manx shearwaters showed repeatable patterns of chick growth but not of food provisioning, and several possible explanations for this pattern are discussed. 相似文献
997.
Fibroblast lines derived from normal skin and spontaneous or experimentally induced fibropapillomas of green turtles (Chelonia mydas) were established and propagated in medium composed of a combination of Dulbecco's minimal essential with F12 medium plus 10% fetal bovine serum at 30 degrees C. Fibropapilloma-derived fibroblasts were indistinguishable from normal skin fibroblasts in vitro. Tumor lines did not exhibit loss of contact inhibition, anchorage independence, or reduced serum requirements. Inoculation of primary and early-passage tumor cells into the medial margin of the pinna of C57BL/6J-nu/nu, C.B17-scid/scid, or NOD-scid/scid mice, however, resulted in fibroma formation, whereas inoculation of normal skin fibroblasts did not. Tumor-derived cells inoculated into the flanks of mice did not form tumors. The turtle origin of fibroblasts in tumors from mouse ears was confirmed by immunohistochemical and karyotype analysis. Fibroblast lines that were established from mouse ear fibromas had the normal karyotype (modal 2N = 55) of C. mydas. The cooler anatomic sites (ears) of immunodeficient mice are useful for confirming the tumorigenic (transformed) phenotype of green turtle fibropapillomatosis-derived fibroblasts. This mouse ear tumorigenicity test should facilitate studies of mechanisms of cellular transformation in green turtle fibropapillomatosis and other neoplastic diseases of poikilothermic vertebrates. 相似文献
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