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1.
The Capricorn silvereye (Zosterops lateralis chlorocephalus) is ideally suited to investigating the genetic basis of body size evolution. We have isolated and characterized a set of microsatellite markers for this species. Seven out of 11 loci were polymorphic. The number of alleles detected ranged from two to five and observed heterozygosities between 0.12 and 0.67. One locus, ZL49, was found to be sex‐linked. This moderate level of diversity is consistent with that expected in an isolated, island population.  相似文献   
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Pulmonary clearance (PCl) of inhaled aerosolized 99mTc-diethylenetriamine pentaacetic acid (DTPA) across the alveolocapillary membrane is diffusion limited. Therefore, if the mixing of the 99mTc-DTPA in the aqueous hypophase underlying surfactant is slow or incomplete or if there were no hypophase, an increase in the alveolar surface area occupied by 99mTc-DTPA particles would increase the absorption rate. The aim of this study was to examine whether there is an effect on PCl of changing the number of inhaled particles. The change in particle number was accomplished by a setup of four parallel jet nebulizers feeding a central delivery chamber of 400 cm3. We performed two kinds of experiments in eight healthy nonsmokers between 28 and 52 yr of age. In the first experiment, 99mTc-DTPA in saline was nebulized in one nebulizer, while saline was nebulized in the other three. In the second experiment the number of inhaled particles containing 99mTc-DTPA was increased by a factor of four by nebulizing 99mTc-DTPA in saline in all four nebulizers simultaneously. Increasing the number of inhaled 99mTc-DTPA particles caused an increase in PCl of 24.2% (P less than 0.01). We conclude that there is a slight but significant effect of changing the number of DTPA particles on PCl and that this is probably due to an uneven mixing of the 99mTc-DTPA in the aqueous hypophase underlying the surfactant lining and the alveoli.  相似文献   
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Delivery was induced by an intravenous infusion of prostaglandin F2alpha (PGF2alpha) in gradually increasing doses in 30 consecutive cases of fetal death in utero after the 28th week of gestation. Twenty patients delivered during the first day of prostaglandin administration, 9 on the second day, and 1 patient not until the third day of infusion. It is concluded, that intravenous PGF2alpha appears to be superior to oxytocin in termination of pregnancy under these conditions.  相似文献   
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Infectivity and effects on host of a long-term stored aqueous suspension of Paranosema locustae on juveniles of Dichroplus maculipennis, a pest grasshopper in parts of the Pampas and Patagonia, were evaluated. Infections developed in 90–97.8% of treated individuals. Mortality increased with time, reaching highest values at 30–40 days post-inoculation (79.5–100%). Infected nymphs showed significantly slower development.  相似文献   
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This clinical study is a first attempt to use autofluorescence for recurrence diagnosis of skin cancer in postoperative scars. The proposed diagnostic parameter is based on a reduction in scar autofluorescence, evaluated in the green spectral channel. The validity of the method has been tested on 110 postoperative scars from 56 patients suspected of non‐melanoma skin cancer, with eight patients (13 scars) available for the repeated examination. The recurrence diagnosis within a scar has been made after two subsequent autofluorescence check‐ups, representing the temporal difference between the scar autofluorescence amplitudes as a vector. The recognition of recurrence has been discussed to represent the significant deviations from the value of vector angle θ. This new autofluorescence‐based method can be easily integrated into the postoperative monitoring of surgical scars and can help diagnose the recurrence of skin cancer from the early stage of scar development.  相似文献   
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The ability of epithelia to migrate and cover wounds is essential to maintaining their functions as physical barriers. Wounding induces many cues that may affect the transition to motility, including the immediate mechanical perturbation, release of material from broken cells, new interactions with adjacent extracellular matrix, and breakdown of physical separation of ligands from their receptors. Depending on the exact nature of wounds, some cues may be present only transiently or insignificantly. In many epithelia, activation of the epidermal growth factor receptor (EGFR) is a central event in induction of motility, and we find that its continuous activation is required for progression of healing of wounds in sheets of corneal epithelial cells. Here, we examine the hypothesis that edges, which are universally and continuously present in wounds, are a cue. Using a novel culture model we find that their presence is sufficient to cause activation of the EGFR and increased motility of cells in the absence of other cues. Edges that are bordered by agarose do not induce activation of the EGFR, indicating that activation is not due to loss of any specific type of cell–cell interaction but rather due to loss of physical constraints.  相似文献   
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Human placentas of different stages of development were histochemically analyzed for expression of endogenous sugar-binding proteins using a panel of biotin-conjugated, chemically glycosylated probes with specificity for beta-galactosides, alpha-galactosides, alpha-mannosides, alpha-fucosides and alpha-glucosides. Temporal differences in the expression of sugar-binding proteins and different patterns of staining of the component cell types of human placenta were discerned, especially pronounced for alpha-fucoside-specific binding in the trophoblast and alpha-glucoside-specific binding in fetal and maternal macrophages. Fractionation of salt and detergent extracts from human placentas by affinity chromatography on columns with immobilized carbohydrates or glycoproteins substantiated the histochemically detectable temporal changes on the basis of alterations in the pattern of individual sugar-binding proteins, as determined by gel electrophoresis under denaturing conditions. Analysis of the trophoblastic layer primarily disclosed the presence of several additional sugar-binding proteins (lectins) in comparison to full-term placenta. The presence and developmental changes of such endogenous sugar receptors may lead to specific carbohydrate-protein interactions of physiological significance with similarly developmentally regulated carbohydrated portions of glyco-conjugates, already detected in human placenta by plant lectins.  相似文献   
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