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1.
The structure and evolution of the spider monkey delta-globin gene   总被引:1,自引:0,他引:1  
We have isolated the delta-globin gene of the New-World spider monkey, Ateles geoffroyi, and compared its nucleotide sequence with those of other primate delta- and beta-globin genes. Among primate delta-globin genes, the rate of nonsynonymous substitutions is much less than the rate of synonymous substitutions. This suggests that primate delta- globin genes may remain under evolutionary conservation, perhaps because hemoglobin A2 has an as yet unknown physiological importance.   相似文献   
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gamma-L-Glutaminyl-[3,5-3H]4-hydroxybenzene was synthesized in order to study the kinetics of its hydroxylation by tyrosinase purified from Agaricus bisporus and to explore its role in the induction of the dormant state in the spores of this species. It was found to be unique among the monophenolic substrates for tyrosinase in that the lag period for the hydroxylation reaction decreased with increasing substrate concentration. Unlike previously studied compounds, this phenol appeared to function as an electron donor, allowing it to act as its own co-substrate in the hydroxylation reaction. Its catechol product, gamma-L-glutaminyl-3,4-dihydroxybenzene, was found to be a superior co-substrate, yielding its electrons more readily (oxidation peak potential +0.18 V as compared with +0.65 V for the phenol). In situ periodate oxidation of gamma-L-glutaminyl-3,4-dihydroxybenzene to gamma-L-glutaminyl-3,4-benzoquinone confirmed the co-substrate role of the catechol in the hydroxylation reaction. The tyrosinase-mediated oxidation of gamma-L-glutaminyl-3,4-dihydroxybenzene to gamma-L-glutaminyl-3,4-benzoquinone occurred with an apparent Km = 1.54 mM and Vmax = 0.36 mmol/min/mg of enzyme. gamma-L-Glutaminyl-4-hydroxybenzene acted as an inhibitor of the oxidation reaction.  相似文献   
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The efficient seeding of juvenile mussels is critical to the sustainability and profitability of mussel aquaculture. However, seeding mussels is highly inefficient, with many juveniles being lost in the following few months. One possible cause of these losses could be the development of biofouling assemblages. Therefore, the relationships between biofouling accumulation and losses of juveniles were assessed. Losses of juvenile mussels were initially high (42.9–49.1% over approximately one to two weeks), with lower rates of loss over the following four to five months. Biofouling development followed a successional pattern beginning with colonisation by amphipods, subsequent establishment of macroalgae, and the formation of an assemblage dominated by mussels and sessile invertebrates. However, biofouling development did not play a major role in the loss of juveniles. Rather, large-scale losses of mussels occurred shortly after seeding when biofouling was scant, suggesting alternative causes of loss were in operation.  相似文献   
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The larval life of the spiny lobster Jasus edwardsii is one of the longest and most complex of any marine organism and is poorly understood due to the difficulty of studying cryptic, pelagic organisms. Hence, the capacity for active swimming in the phyllosoma, puerulus and juvenile stages and the use of possible metabolic fuel reserves was inferred from a number of enzyme activities, including citrate synthase, lactate dehydrogenase, and HOAD. High activities of CS and LDH in abdominal tissues of Stage 11 phyllosoma and pueruli are consistent with a capacity to commence active on-shore movement. The activities of LDH and HOAD showed positive allometry while CS was independent of body mass. The body mass dependence of LDH activity may reflect the developing ability of the lobster to initiate brief escape manoeuvres, and the scaling of HOAD reflects an increased use of lipid fuel reserves. Aerobic enzyme activities were higher in abdominal tissues than in cephalic tissues of pelagic pueruli, but high activities appear in the cephalic tissues of juveniles. These changes mirror a developmental shift in activity from pelagic oceanic swimming to a benthic existence on the seabed of the near shore. The low LDH activity in pueruli confirmed previous findings that they have limited feeding capacity, with carbohydrate contributing little towards the major energy reserves. The highest LDH activities occur in the abdominal muscles of juveniles and correlate with rapid tail-flicking escape behaviour. The activities of HOAD increased throughout development, and in the abdominal tissues of juveniles, may reflect lipid transformation and accumulation as an energy reserve. Enzyme activities, therefore, provide useful information concerning migratory behaviour that is presently unavailable from ecological studies.  相似文献   
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Background  

Autonomic neuropathy is a common and serious complication of diabetes. Early detection is essential to enable appropriate interventional therapy and management. Dynamic pupillometry has been proposed as a simpler and more sensitive tool to detect subclinical autonomic dysfunction. The aim of this study was to investigate pupil responsiveness in diabetic subjects with and without cardiovascular autonomic neuropathy (CAN) using dynamic pupillometry in two sets of experiments.  相似文献   
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The global loss of marine ecosystem engineers has caused an unprecedented decline in biodiversity. Although wild shellfish habitats have been shown to support biodiverse ecosystems, little is known about how biodiversity is altered by restored shellfish habitats, particularly mussels. To explore the biodiversity response to restored mussel habitats we deposited mussels on the seafloor in 1.5?×?1.5 m plots across a gradient of benthic environments. To understand a holistic community response, this study looks at the response of three faunal classifications over 1 year: infauna, epifauna, and pelagic fauna, compared with adjacent control plots (no mussels). The restored mussel habitats recorded 42 times more demersal fish than control areas, while macroalgae and mobile benthic invertebrates had over a twofold increase in abundance. Overall, the addition of mussels to the seafloor resulted in a general reduction of infaunal abundance and biodiversity, but an increase in epifaunal and pelagic faunal abundances, specifically from those species that benefit from benthic habitat complexity and an increase in food availability. From a management perspective, we highlight location-specific differences to consider for future restoration efforts, including environmental conditions and potential observed factors such as nearby sources of species, particularly predators, and relevant demersal fish ranges. Ultimately, measuring biodiversity responses in small-scale studies will serve as a valuable guide for larger scale restoration efforts and this study recommends considerations to enhance biodiversity outcomes in restored mussel habitats.

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Auditory information is widely used throughout the animal kingdom in both terrestrial and aquatic environments. Some marine species are dependent on reefs for adult survival and reproduction, and are known to use reef noise to guide orientation towards suitable habitat. Many others that forage in food-rich inshore waters would, however, benefit from avoiding the high density of predators resident on reefs, but nothing is known about whether acoustic cues are used in this context. By analysing a sample of nearly 700,000 crustaceans, caught during experimental playbacks in light traps in the Great Barrier Reef lagoon, we demonstrate an auditory capability in a broad suite of previously neglected taxa, and provide the first evidence in any marine organisms that reef noise can act as a deterrent. In contrast to the larvae of species that require reef habitat for future success, which showed an attraction to broadcasted reef noise, taxa with a pelagic or nocturnally emergent lifestyle actively avoided it. Our results suggest that a far greater range of invertebrate taxa than previously thought can respond to acoustic cues, emphasising yet further the potential negative impact of globally increasing levels of underwater anthropogenic noise.  相似文献   
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