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151.
152.
Crustacean and cheliceratan hemocyanins (oxygen-transport proteins) and
insect hexamerins (storage proteins) are homologous gene products, although
the latter do not bind oxygen and do not possess the copper- binding
histidines present in the hemocyanins. An alignment of 19 amino acid
sequences of hemocyanin subunits and insect hexamerins was made, based on
the conservation of elements of secondary structure observed in X-ray
structures of two hemocyanin subunits. The alignment was analyzed using
parsimony and neighbor-joining methods. Results provide strong indications
for grouping together the sequences of the 2 crustacean hemocyanin
subunits, the 5 cheliceratan hemocyanin subunits, and the 12 insect
hexamerins. Within the insect clade, four methionine- rich proteins, four
arylphorins, and two juvenile hormone-suppressible proteins from
Lepidoptera, as well as two dipteran proteins, form four separate groups.
In the absence of an outgroup sequence, it is not possible to present
information about the ancestral state from which these proteins are
derived. Although this family of proteins clearly consists of homologous
gene products, there remain striking differences in gene organization and
site of biosynthesis of the proteins within the cell. Because studies on
18S and 12S rRNA sequences indicate a rather close relationship between
insects and crustaceans, we propose that hemocyanin is the ancestral
arthropod protein and that insect hexamerins lost their copper-binding
capability after divergence of the insects from the crustaceans.
相似文献
153.
Carolee J Winstein Steven L Wolf Alexander W Dromerick Christianne J Lane Monica A Nelsen Rebecca Lewthwaite Sarah Blanton Charro Scott Aimee Reiss Steven Yong Cen Rahsaan Holley Stanley P Azen 《BMC neurology》2013,13(1):1-19
Background
Residual disability after stroke is substantial; 65% of patients at 6 months are unable to incorporate the impaired upper extremity into daily activities. Task-oriented training programs are rapidly being adopted into clinical practice. In the absence of any consensus on the essential elements or dose of task-specific training, an urgent need exists for a well-designed trial to determine the effectiveness of a specific multidimensional task-based program governed by a comprehensive set of evidence-based principles. The Interdisciplinary Comprehensive Arm Rehabilitation Evaluation (ICARE) Stroke Initiative is a parallel group, three-arm, single blind, superiority randomized controlled trial of a theoretically-defensible, upper extremity rehabilitation program provided in the outpatient setting. The primary objective of ICARE is to determine if there is a greater improvement in arm and hand recovery one year after randomization in participants receiving a structured training program termed Accelerated Skill Acquisition Program (ASAP), compared to participants receiving usual and customary therapy of an equivalent dose (DEUCC). Two secondary objectives are to compare ASAP to a true (active monitoring only) usual and customary (UCC) therapy group and to compare DEUCC and UCC.Methods/design
Following baseline assessment, participants are randomized by site, stratified for stroke duration and motor severity. 360 adults will be randomized, 14 to 106 days following ischemic or hemorrhagic stroke onset, with mild to moderate upper extremity impairment, recruited at sites in Atlanta, Los Angeles and Washington, D.C. The Wolf Motor Function Test (WMFT) time score is the primary outcome at 1 year post-randomization. The Stroke Impact Scale (SIS) hand domain is a secondary outcome measure. The design includes concealed allocation during recruitment, screening and baseline, blinded outcome assessment and intention to treat analyses. Our primary hypothesis is that the improvement in log-transformed WMFT time will be greater for the ASAP than the DEUCC group. This pre-planned hypothesis will be tested at a significance level of 0.05.Discussion
ICARE will test whether ASAP is superior to the same number of hours of usual therapy. Pre-specified secondary analyses will test whether 30 hours of usual therapy is superior to current usual and customary therapy not controlled for dose.Trial registration
http://www.ClinicalTrials.gov Identifier: NCT00871715 相似文献154.
155.
Ultimate tensile strength of fetal and adult human tendons 总被引:1,自引:0,他引:1
156.
This investigation was undertaken to determine the densities of fresh human compact and cancellous bone, with its marrow constituents intact, and compact and cancellous bone taken from embalmed cadavers. The density of 107 bone specimens was determined on the basis of the weight and volume of each specimen. Mean density results were: (1) fresh compact bone, 1.85; (2) fresh cancellous bone, 1.08; (3) embalmed compact bone, 1.85; and (4) embalmed cancellous bone, 1.09. Embalming did not appear to have altered the density of either compact or cancellous bone. It was observed also that the densities of several bone specimens taken from the same area of one bone varied greatly. 相似文献
157.
158.
Boundary elements or insulators subdivide eukaryotic chromosomes into a series of structurally and functionally autonomous domains. They ensure that the action of enhancers and silencers is restricted to the domain in which these regulatory elements reside. Three models, the roadblock, sink/decoy, and topological loop, have been proposed to explain the insulating activity of boundary elements. Strong predictions about how boundaries will function in different experimental contexts can be drawn from these models. In the studies reported here, we have designed assays that test these predictions. The results of our assays are inconsistent with the expectations of the roadblock and sink models. Instead, they support the topological loop model. 相似文献
159.
Introduction
Graphic warnings (GWs) on cigarette packs are widely used internationally and perhaps will be in the US but their impact is not well understood. This study tested support for competing hypotheses in different subgroups of young adults defined by their history of cigarette smoking and individual difference variables (e.g., psychological reactance). One hypothesis predicted adaptive responding (GWs would lower smoking-related intentions) and another predicted defensive responding (GWs would raise smoking-related intentions).Methods
Participants were an online sample of 1,169 Americans ages 18–24, who were randomly assigned either to view nine GWs designed by the FDA or to a no-label control. Both the intention to smoke in the future and the intention to quit smoking (among smokers) were assessed before and after message exposure.Results
GWs lowered intention to smoke in the future among those with a moderate lifetime smoking history (between 1 and 100 cigarettes), and they increased intention to quit smoking among those with a heavy lifetime smoking history (more than 100 cigarettes). Both effects were limited to individuals who had smoked in some but not all of the prior 30 days (i.e., occasional smokers). No evidence of defensive “boomerang effects” on intention was observed in any subgroup.Conclusion
Graphic warnings can reduce interest in smoking among occasional smokers, a finding that supports the adaptive-change hypothesis. GWs that target occasional smokers might be more effective at reducing cigarette smoking in young adults. 相似文献160.
Yasmeen B. Ross Mahbubul Hoque Jesse D. Blanton Erin D. Kennedy Md Sohel Rana Sanya Tahmina Sarah Bonaparte Jennifer R. Head Ryan M. Wallace 《PLoS neglected tropical diseases》2022,16(8)
Rabies is one of the most lethal infectious diseases, with those living in Asia and Africa having the highest risk of dying from rabies. We conducted a knowledge, attitudes and practices survey in urban and peri-urban areas of Bangladesh to describe canine bite rates, rabies knowledge, and healthcare seeking behaviors and barriers to human and dog vaccination. A bite risk assessment score (BRAS) and healthcare-seeking behavior score (HSBS) was calculated for each bite victim. Respondents were given two hypothetical situations to assess potential behaviors after a bite and willingness to pay for rabies vaccine and immunoglobulin. In total, 2,447 households participated in the survey and 85 bite victims were identified. The BRAS identified that 31% of bites posed no risk of rabies transmission. Multivariate analyses showed that living in Chittagong (β = 1.4; 95% CI: 0.1, 2.7) was associated with a higher HSBS. Findings presented here provide useful information regarding bite occurrences, healthcare-seeking behaviors, and a need for strategies to increase rabies awareness. 相似文献