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101.
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J. Shepherd R. Morley G. Adshead G. Gillett M. A. Knight 《BMJ (Clinical research ed.)》1995,311(7020):1617-1621
Currently the management of adult victims of violence by general practitioners and accident and emergency departments is reactive, concerned almost exclusively with the management of physical injuries. Professor Jonathan Shepherd outlines some ideas for a more proactive approach on the part of doctors to improve the protection and support of vulnerable people; to deal with psychological sequelae; to take the responsibility of making an official complaint to the police away from seriously injured people, who are unable to give or withhold consent to disclosure; and to prevent assailants inflicting further injuries. We asked a sociologist, a psychiatrist, a moral philosopher, and a police surgeon for their comments. 相似文献
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Normal human monocyte-derived macrophages maintained in medium containing whole serum exhibited saturable degradation of low-density lipoprotein (LDL) that was mediated by LDL receptors. This degradation required a higher concentration of LDL to achieve one-half saturation than that in cells preincubated with lipoprotein-deficient serum (LPDS). Studies of short-term uptake and of heparin-releasable binding of LDL showed that binding to the surface receptors was the limiting factor for degradation under both conditions and that the LDL receptors expressed by cells in whole serum had a significantly lower affinity for LDL than those in cells pre-incubated in LPDS. LDL receptors in monocyte-macrophages could mediate the uptake and degradation of complexes between apolipoprotein E (apoE) and phospholipid. The receptors in cells pre-incubated in LPDS bound the complexes and LDL with apparently the same affinity and in approximately the same molar ratio. Receptors in cells maintained with whole serum did not have a lower affinity for the complexes than cells pre-incubated in LPDS, although the molar ratio of maximum degradation of LDL to that of complexes was greater. 相似文献
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Anthropogenic CO2 emissions are projected to lower the pH of the ocean 0.3 units by 2100. Previous studies suggested that Prochlorococcus and Synechococcus, the numerically dominant phytoplankton in the oceans, have different responses to elevated CO2 that may result in a dramatic shift in their relative abundances in future oceans. Here we showed that the exponential growth rates of these two genera respond to future CO2 conditions in a manner similar to other cyanobacteria, but Prochlorococcus strains had significantly lower realized growth rates under elevated CO2 regimes due to poor survival after exposure to fresh culture media. Despite this, a Synechococcus strain was unable to outcompete a Prochlorococcus strain in co-culture at elevated CO2. Under these conditions, Prochlorococcus' poor response to elevated CO2 disappeared, and Prochlorococcus' relative fitness showed negative frequency dependence, with both competitors having significant fitness advantages when initially rare. These experiments suggested that the two strains should be able to coexist indefinitely in co-culture despite sharing nearly identical nutritional requirements. We speculate that negative frequency dependence exists due to reductive Black Queen evolution that has resulted in a passively mutualistic relationship analogous to that connecting Prochlorococcus with the ‘helper’ heterotrophic microbes in its environment. 相似文献
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Michele Preti Alan Lee Knight María Valentina Mujica Esteban Basoalto Sebastian Larsson Herrera Marco Tasin Sergio Angeli 《Journal of Applied Entomology》2021,145(8):822-830
Nineteen host plant volatiles (HPVs) were screened for attractivity to adult codling moth Cydia pomonella (L.) as a fourth component of core blends (3K) including (E,Z)-2,4-ethyl decadienoate, (E)-4,8-dimethyl-1,3,7-nonatriene and acetic acid. Each new quaternary combination was compared with a previously reported attractive bisexual lure (4K), consisting of the 3K blend plus 6-ethenyl-2,2,6-trimethyloxan-3-ol (pyranoid linalool oxide, pyrLOX). All lure evaluations were conducted in apple, Malus domestica (Borkhausen). Several compounds were found to significantly lower total and/or female catches when added to the 3K blend, including (Z)-3-hexenol, (E)-2-hexanal and hexyl butanoate (female and total moths), and (Z)-3-hexenyl acetate and linalool (female moths). Other compounds when added to the 3K blend did not increase or decrease moth catches, including methyl salicylate, (E)-β-ocimene, limonene, β-caryophyllene, butyl hexanoate, farnesol, terpineol, terpinen-4-ol and α-pinene. A few added compounds significantly increased moth catches compared with the 3K blend, including β-pinene (male moths), (Z)-jasmone (male and total moths), (E)-β-farnesene and β-myrcene (female and total moths), and (E,E)-α-farnesene (male, female, and total moths). In addition, each of these five compounds when added to the 3K core blend performed similarly to the 4K lure (male, females, and total moths). Further studies should expand these results through tests of these and other new blends with a range of component ratios and total loading amounts. Field trials should also be replicated within all host crops of codling moth and across major geographical production regions. 相似文献