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471.
Abstract. The strategy of flowering available to monoecious fig-trees ( Ficus spp., Moraceae) is restricted by the obligate mutualistic relationship they have with their pollinating wasps (Hymenoptera, Agaonidae). Flowering should be synchronous within a tree, asynchronous between trees, random in the yearly cycle, and irregular from year to year. Exceptions have been predicted to occur in a population that inhabits both seasonally dry and adjacent riparian habitats. Ficus thonningii B1 meets these criteria in Harare, Zimbabwe. The vegetative and reproductive phenologies of twenty-five mature trees growing close together but in three habitats (watered, non-watered and intermediate) were studied over 32 months. Trees were generally deciduous between April and August in all habitats. In contrast fruiting phenology was habitat dependant. Watered trees conformed to the general model, but half the trees in the seasonally dry habitat flowered synchronously in the cool dry season. This strategy may result in these trees having relatively superior female reproductive function. 相似文献
472.
Robin M. Murray Mitch Dowsett Mark E. Cooper Terri J. Allen Peter Lawson Harold Story Rodney Syme 《Steroids》1987,50(4-6):647-648
Fourteen men with benign prostatic hypertrophy were treated with the aromatase inhibitor aminoglutethimide for periods of up to 3 months. LH, FSH and testosterone levels rose within one week and remained elevated, while estradiol levels decreased. Despite significant changes in these hormones there was no change in urine flow rates or prostatic size over the study period. 相似文献
473.
474.
Terri J. Cleary Roger B. J. Benson Patricia A. Holroyd Paul M. Barrett 《Palaeontology》2020,63(5):753-774
Turtles are key components of modern vertebrate faunas and their diversity and distributions are likely to be affected by anthropogenic climate change. However, there is limited baseline data on turtle taxonomic richness through time or assessment of their past responses to global environmental change. We used the extensive Triassic–Palaeogene (252–223 Ma) fossil record of terrestrial and freshwater turtles to investigate diversity patterns, finding substantial variation in richness through time and between continents. Globally, turtle richness was low from their Triassic origin until the Late Jurassic. There is strong evidence for high richness in the earliest Cretaceous of Europe, becoming especially high following the Cretaceous Thermal Maximum and declining in all continents by the end-Cretaceous. At the K–Pg boundary, South American richness levels changed little while North American richness increased, becoming very high during the earliest Palaeogene (Danian). Informative data are lacking elsewhere for this time period. However, the Selandian–Thanetian interval, approximately 5 myr after the K–Pg mass extinction, shows low turtle richness in Asia, Europe and South America, suggesting that the occurrence of exceptional turtle richness in the post-extinction Paleocene fauna of North America is not globally representative. Richness decreased over the Eocene–Oligocene boundary in North America but increased to its greatest known level for Europe, implying very different responses to dramatic climatic shifts. Time series regressions suggest number of formations sampled and palaeotemperature are the primary influencers of face-value richness counts, but additional factors not tested here may also be involved. 相似文献
475.
Ifeanyi Michael Amadi Vishal Agrawal Terri Christianson Cameron Bardliving Parviz Shamlou Jonathan H. LeBowitz 《Biotechnology progress》2020,36(3):e2974
Difficult-to-express (DTE) recombinant proteins such as multi-specific proteins, DTE monoclonal antibodies, and lysosomal enzymes have seen difficulties in manufacturability using Chinese hamster ovary (CHO) cells or other mammalian cells as production platforms. CHO cells are preferably used for recombinant protein production for their ability to secrete human-like recombinant proteins with posttranslational modification, resistance to viral infection, and familiarity with drug regulators. However, despite huge progress made in engineering CHO cells for high volumetric productivity, DTE proteins like recombinant lysosomal sulfatase represent one of the poorly understood proteins. Furthermore, there is growing interest in the use of microRNA (miRNA) to engineer CHO cells expressing DTE proteins to improve cell performance of relevant bioprocess phenotypes. To our knowledge, no research has been done to improve CHO cell production of DTE recombinant lysosomal sulfatase using miRNA. We identified miR-23a and miR-377 as miRNAs predicted to target SUMF1, an activator of sulfatases, using in silico prediction tools. Transient inhibition of CHO endogenous miR-23a/miR-377 significantly enhanced recombinant sulfatase enzyme-specific activity by ~15–21% compared to scramble without affecting cell growth. Though inhibition of miR-23a/miR-377 had no significant effect on the mRNA and protein levels of SUMF1, overexpression of miR-23a/377 caused ~30% and ~27–29% significant reduction in endogenous SUMF1 protein and mRNA expression levels, respectively. In summary, our data demonstrate the importance of using miRNA to optimize the CHO cell line secreting DTE recombinant lysosomal sulfatase. 相似文献
476.
Terri L. Zucker Kristin W. Samuelson Frederick Muench Melanie A. Greenberg Richard N. Gevirtz 《Applied psychophysiology and biofeedback》2009,34(2):135-143
Recent studies have found a significant association between PTSD and low heart rate variability (HRV), a biomarker of autonomic
dysregulation. Research indicates that respiratory sinus arrhythmia (RSA) biofeedback increases HRV while reducing related
pathological symptoms. This controlled pilot study compared RSA biofeedback to progressive muscle relaxation (PMR) as adjunctive
interventions for 38 persons with PTSD symptoms in a residential treatment facility for a substance use disorder. Both groups
were assessed at pre-intervention and 4-week post-intervention. Group × time interactions revealed significantly greater reductions
in depressive symptoms and increases in HRV indices for the RSA group. Both groups significantly reduced PTSD and insomnia
symptoms and a statistical trend was observed for reduced substance craving for the RSA group. Increases in HRV were significantly
associated with PTSD symptom reduction. Overall, these results provide preliminary support for the efficacy of RSA biofeedback
in improving physiological and psychological health for individuals with PTSD. 相似文献
477.
Terri P. Freemantle Tim Wacher John Newby Nathalie Pettorelli 《African Journal of Ecology》2013,51(3):482-492
Habitat evaluation is considered an essential step for assessing the potential for an area to support a viable reintroduced population. Remote sensing techniques can support such investigations, by greatly enhancing the temporal and spatial coverage of habitat assessments. This study makes use of freely available earth observation data to evaluate the suitability of the Ouadi Rimé–Ouadi Achim Game Reserve in central Chad for the reintroduction of the Scimitar‐horned Oryx. The reserve was the last stronghold of the species within its historical range, prior to extinction in the wild in the 1980s, providing a basis for reintroduction. Results show that since the 1980s, there has been a steady increase in average annual precipitation and satellite‐derived estimates of primary production. The spatial downscaling of the average trend in primary production showed that the north of the protected area exhibited a drying trend over the period 1982–2008, while the south was associated with intense greening. As a result, the subdesert transition zone preferred by oryx is currently narrowing. If this is correct, this implies a potential reduction of favourable habitat for the oryx, which could have detrimental effects on the success of establishing a self‐sustaining reintroduced population. 相似文献
478.