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211.
The importance of lymphatic vessels in a myriad of human diseases is rapidly gaining recognition; lymphatic vessel dysfunction is a feature of disorders including congenital lymphatic anomalies, primary lymphoedema and obesity, while improved lymphatic vessel function increases the efficacy of immunotherapy for cancer and neurological disease and promotes cardiac repair following myocardial infarction. Understanding how the growth and function of lymphatic vessels is precisely regulated therefore stands to inform the development of novel therapeutics applicable to a wide range of human diseases. Lymphatic vascular development is initiated during embryogenesis following establishment of the major blood vessels and the onset of blood flow. Lymphatic endothelial progenitor cells arise from a combination of venous and non-venous sources to generate the initial lymphatic vascular structures in the vertebrate embryo, which are then further ramified and remodelled to elaborate an extensive lymphatic vascular network. Signalling mediated via vascular endothelial growth factor (VEGF) family members and vascular endothelial growth factor receptor (VEGFR) tyrosine kinases is crucial for development of both the blood and lymphatic vascular networks, though distinct components are utilised to different degrees in each vascular compartment. Although much is known about the regulation of VEGFA/VEGFR2 signalling in the blood vasculature, less is understood regarding the mechanisms by which VEGFC/VEGFD/VEGFR3 signalling is regulated during lymphatic vascular development. This review will focus on recent advances in our understanding of the cellular and molecular mechanisms regulating VEGFA-, VEGFC- and VEGFD-mediated signalling via VEGFRs which are important for driving the construction of lymphatic vessels during development and disease. 相似文献
212.
Basso Michael R.; Lowery Natasha; Neel Jackie; Purdie Rod; Bornstein Robert A. 《Canadian Metallurgical Quarterly》2002,16(1):84
Previous research has demonstrated broad neurobehavioral abnormalities in bipolar affective disorder (cf. G. Cassens, L. Wolfe, & M. Zola, 1990). However, there have been no comparisons of neuropsychological function across patients with manic, depressed, or mixed subtypes. In the present study, 37 manic, 24 mixed-episode, and 25 depressed bipolar I inpatients and 34 control subjects were administered a brief battery of neuropsychological tests. The multivariate and univariate effects of participant group on the neuropsychological measures were uniformly significant (p 相似文献
213.
Macklin Michael L.; Metzger Linda J.; Litz Brett T.; McNally Richard J.; Lasko Natasha B.; Orr Scott P.; Pitman Roger K. 《Canadian Metallurgical Quarterly》1998,66(2):323
The authors examined the relation between intelligence and posttraumatic stress disorder (PTSD) by studying the association among precombat intelligence, current intelligence, and self-reported PTSD symptoms. Military aptitude test results were obtained in 59 PTSD and 31 non-PTSD Vietnam combat veterans who had undergone a psychodiagnostic interview and current intelligence testing. People with lower precombat intelligence were more likely to develop PTSD symptoms as assessed by the Clinician-Administered PTSD Scale even after adjustment for extent of combat exposure. The association between current intelligence and PTSD was no longer significant after adjusting for precombat intelligence. These results suggest that lower pretrauma intelligence increases risk for developing PTSD symptoms, not that PTSD lowers performance on intelligence tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
214.
215.
Metzger Linda J.; Paige Stephen R.; Carson Margaret A.; Lasko Natasha B.; Paulus Lynn A.; Pitman Roger K.; Orr Scott P. 《Canadian Metallurgical Quarterly》2004,113(2):324
Researchers have proposed that depression and particular types of anxiety are associated with unique patterns of regional brain activation. The authors examined the relationship among posttraumatic stress disorder (PTSD), anxiety, and depressive symptoms and frontal, temporal, and parietal EEG alpha asymmetry in female Vietnam War nurse veterans. The results indicate that PTSD arousal symptoms are associated with increased right-sided parietal activation. However, the combination of arousal, depression, and their interaction explain more than twice the variance in parietal asymmetry compared with arousal alone. The results support the contention that the association between anxiety and right-sided posterior activation is specific to the anxious arousal subtype. These findings underscore the importance of isolating, both theoretically and statistically, emotional subcomponents in studies of regional brain activation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
216.
Ewa Tocha Holger Schönherr G. Julius Vancso Natasha Siebelt 《Journal of the American Ceramic Society》2005,88(9):2498-2503
The nanotribological properties of nanostructured thin films of tetragonal ZrO2 on oxidized Si (100) were studied as a function of grain size and relative humidity (RH) by atomic force microscopy. The nanostructured ZrO2 showed a 50% decrease in friction coefficient μ compared with oxidized Si (100) in dry nitrogen atmosphere and 40% RH. A maximum of μ was observed at ca. 40% RH for both samples, while there were insignificant differences in μ for ZrO2 samples with grain sizes between 12 and 30 nm. The good tribological properties open the possibility for nanostructured zirconia to be applied as wear-resistant, low friction coatings on various materials. 相似文献
217.
Sorin Pirau Brandon Liberi Natasha Barbely Narayanan Komerath 《Journal of Mechanical Science and Technology》2016,30(9):3961-3967
Bluff bodies may assume arbitrary attitudes in a flow, causing aerodynamic loads that are sensitive to attitude. The Continuous rotation technique obtains 6-component loads on bluff bodies with 1-degree azimuth resolution about selected axes at a rate of 1 revolution per minute. The load coefficient variation is Fourier transformed and the resulting complex series is truncated in order to obtain rapidly computable, analytical formulae. The method is applied to bluff body shapes including cylinders, a cuboid, a flat plate and a porous box. A cylinder whose length is equal to its diameter, is used to show that rate effects, hysteresis, vortex shedding and other unsteady aerodynamic phenomena are negligible below 10 revolutions per minute. Approaches to generalize the aerodynamic loads on yawed finite cylinders of various aspect ratio are studied. The reasons for differences in aerodynamic load behavior between 2 cylinder models, are analyzed. To complement experiments, the ROTCFD unsteady Navier Stokes code is used to perform diagnostic computations. Methods to generalize the predictions are explored. Maps of the leading coefficients of the Fourier series of each load component over the aspect ratios space, are interpolated. The interpolation varies sharply for aspect ratios between 0.5 to 1. The variation is more gradual beyond aspect ratio 2. By aspect ratio 4, a ‘high aspect ratio’ limit appears to be reached. 相似文献
218.
The common brushtail possum (Trichosurus vulpecula) is a generalist herbivore whose diet includes Eucalyptus leaves that are well defended by plant secondary metabolites (PSM) such as the terpene 1,8-cineole (cineole). We accustomed
possums to a terpene-free diet, then challenged them with the addition of 2% cineole to the diet. Initially, there was a 50%
reduction in total overnight food consumption associated with a marked decrease in the mass of the major feeding bout. After
nine nights, however, cineole tolerance had developed as total food consumption had returned to the control amount. Compared
to the control diet, the cineole diet was eaten in a larger number of smaller bouts, which were also eaten at a slower rate.
The experiment was repeated with animals that had been accustomed to day-time feeding to take blood samples during feeding
sessions. Feeding variables and blood concentration data for cineole were compared on the first and seventh day of the cineole
diet. Although the total food consumed increased 2.5-fold after 7 days of the cineole diet, there was no increase in average
blood cineole concentration, measured as the area under the concentration–time curve. This indicates that induction of liver
enzymes resulted in greater pre-systemic metabolism of cineole and reduced bioavailability. The maximum tolerated blood concentration
of cineole also increased, suggesting some adaptation of the central nervous system to the cineole aversive effects. This
appears to be the first report in a vertebrate herbivore that consumption of a dietary PSM leads to metabolism induction and
that this contributes to development of tolerance to the PSM. Overall, herbivores adapt to newly encountered dietary PSMs
by immediate changes in feeding behavior followed by development of increased metabolism of PSM and probably diminished cellular
responsiveness to effects. 相似文献
219.
Cabrera Natasha J.; Ryan Rebecca M.; Mitchell Stephanie J.; Shannon Jacqueline D.; Tamis-LeMonda Catherine S. 《Canadian Metallurgical Quarterly》2008,22(4):643
Using data from a racially and ethnically diverse sample of low-income mothers of 2-year-old children participating in the Early Head Start Research and Evaluation Project (N = 883), the authors examined fathers' education and employment, mother-father relationship, and mothers' relationships with kin in the household to explain variation in nonresident father involvement across racial and ethnic groups. Nonresident White fathers were less involved with their children than were African American and Latino fathers. This difference was explained by the status of mother-father relationships. White nonresident fathers were less likely than minority nonresident fathers to maintain romantic relationships with their child's mother. Mothers in the White father group were also more likely to re-partner, which negatively related to biological fathers' involvement. These findings suggest that approaches to strengthen nonresident father involvement in children's lives need to consider how father ethnicity and mother-father relations are associated with differential patterns of father involvement. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
220.
Spencer Larkin Natasha Kyprianou 《International journal of molecular sciences》2013,14(9):18421-18436
Urologic tumors continue to represent a huge fraction of cancer cases in the United States, with over 376,310 estimated new diagnoses in 2013. As with many types of tumors, urologic tumors vary greatly in their phenotype, ranging from minimally invasive to malignancies possessing great metastatic potential. The increasing need for more efficient and less invasive methods of cancer detection, as well as the ability to predict severity of the disease phenotype is readily evident—yet reliable methods remain elusive in a clinical setting today. Comprehensive panels of gene clusters are being developed toward the generation of molecular signatures in order to better diagnose urologic malignancies, and identify effective treatment strategies in the emerging era of personalized medicine. In this review, we discuss the current literature on the credibility and biomarker value of such molecular signatures in the context of clinical significance relating to the pathological aggressiveness of urologic tumors (prostate, bladder and renal cancer)—also exploiting their predictive potential in the response to treatment. 相似文献