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31.
John Cosh 《BMJ (Clinical research ed.)》2000,320(7227):123
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The dopaminergic agonist apomorphine produces dose-related hypothermia in naive rats as does L-DOPA in carbidopa-pretreated rats. The hypothermic responses to these two dopaminergic drugs were significantly more pronounced and prolonged in the spontaneously hypertensive rat than in normotensive Wistar control rats. The greater sensitivity of the SHR to these drugs was reflected as a leftward shift of the dose-response curves for apomorphine- and L-DOPA-induced hypothermias. 相似文献
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Methods for production of containerized seedlings ofAlnus species were developed which permit nitrogen-fixing nodules to form on the root systems prior to outplanting, in order to provide an early nitrogen input during seedling establishment. The methods are based on procedures for inoculating root systems with suspensions ofFrankia (Actinomycetales), applied either directly in the container cell as a soil drench at the time of seeding, or as a root dip for seedlings transplanted into the containers. Germination of dried, stored seed was enhanced by light and by presoaking for 16 h in water. Pretreatments to overcome seed dormancy or to eliminate fungal pathogens did not further enhance germination. Some loss of seedlings was recorded in the early stages of growth shortly after germination, which is a factor in calculating projected seedling yield. Nodulation and seedling growth were evaluated in terms of growth media characteristics. Seedlings performed well in peat-vermiculite, at soil pH between 5.5 and 8.0. 相似文献
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Amanda Tetlock Christopher K. Yost John Stavrinides Richard G. Manzon 《Applied and environmental microbiology》2012,78(21):7638-7644
Vertebrate metamorphosis is often marked by dramatic morphological and physiological changes of the alimentary tract, along with major shifts in diet following development from larva to adult. Little is known about how these developmental changes impact the gut microbiome of the host organism. The metamorphosis of the sea lamprey (Petromyzon marinus) from a sedentary filter-feeding larva to a free-swimming sanguivorous parasite is characterized by major physiological and morphological changes to all organ systems. The transformation of the alimentary canal includes closure of the larval esophagus and the physical isolation of the pharynx from the remainder of the gut, which results in a nonfeeding period that can last up to 8 months. To determine how the gut microbiome is affected by metamorphosis, the microbial communities of feeding and nonfeeding larval and parasitic sea lamprey were surveyed using both culture-dependent and -independent methods. Our results show that the gut of the filter-feeding larva contains a greater diversity of bacteria than that of the blood-feeding parasite, with the parasite gut being dominated by Aeromonas and, to a lesser extent, Citrobacter and Shewanella. Phylogenetic analysis of the culturable Aeromonas from both the larval and parasitic gut revealed that at least five distinct species were represented. Phenotypic characterization of these isolates revealed that over half were capable of sheep red blood cell hemolysis, but all were capable of trout red blood cell hemolysis. This suggests that the enrichment of Aeromonas that accompanies metamorphosis is likely related to the sanguivorous lifestyle of the parasitic sea lamprey. 相似文献
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John A. Schneider Rakhi Dandona Shravani Pasupneti Vemu Lakshmi Chuanhong Liao Vijay Yeldandi Kenneth H. Mayer 《PloS one》2010,5(7)
Studies of HIV prevention interventions such as pre-exposure prophylaxis (PREP) and circumcision in India are limited. The present study sought to investigate Indian truck-drivers initial commitment to PREP and circumcision utilizing the AIDS Risk Reduction Model. Ninety truck-drivers completed an in-depth qualitative interview and provided a blood sample for HIV and HSV-2 testing. Truck-drivers exhibited low levels of initial commitment towards PREP and even lower for circumcision. However, potential leverage points for increasing commitment were realized in fear of infecting family rather than self, self-perceptions of risk, and for PREP focusing on cultural beliefs towards medication and physicians. Cost was a major barrier to both HIV prevention interventions. Despite these barriers, our findings suggest that the ARRM may be useful in identifying several leverage points that may be used by peers, health care providers and public health field workers to enhance initial commitment to novel HIV prevention interventions in India. 相似文献
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A recent literature review of commentaries and ‘state of the art’ articles from researchers in psychiatric genetics (PMG)
offers a consensus about progress in the science of genetics, disappointments in the discovery of new and effective treatments,
and a general optimism about the future of the field. I argue that optimism for the field of psychiatric molecular genetics
(PMG) is overwrought, and consider progress in the field in reference to a sample estimate of US National Institute of Mental
Health funding for this paradigm for the years 2008 and 2009. I conclude that the amounts of financial investment in PMG is
questionable from an ethical perspective, given other research and clinical needs in the USA. 相似文献