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131.
OBJECTIVES--To examine current targets for glycated haemoglobin as a marker for metabolic control in diabetes mellitus in relation to datasets from several areas, and to consider whether target setting could be improved. DESIGN--Data collected from enhanced care records of general practices for a representative community based sample of people with diabetes. SETTING AND SUBJECTS--3022 people with diabetes on the lists of 37 general practices (total list size 222,550) in South Glamorgan in 1992; samples of glycated haemoglobin had been processed at two laboratories with different methodologies and reference ranges. MAIN OUTCOME MEASURES--Last glycated haemoglobin level measured in subjects for 1992 and published data from other studies considered in relation to existing goals and standards for the metabolic control of diabetes. RESULTS--An ascertainment rate for people with diabetes of 1.36% was obtained. The rate of data capture for haemoglobin A1 was 75.7%, and the mean level for study samples was 10.5% at one laboratory and 10.0% at the other (similar values to those of comparable studies). These mean levels of haemoglobin A1 in representative populations of people with diabetes are poor or very poor according to published standards, including those of the British Diabetic Association. These findings are set in the context of the psychology of goal setting and performance in complex clinical situations. CONCLUSION--Targets for clinical care that are set in the absence of normative data and local feasibility assessments should be treated with caution. Targets are more likely to enhance health care if target setters recognise the importance of psychological aspects of goal setting and motivation. 相似文献
132.
Oligogalacturonic acids (OGAs), derived from plant cell wall pectin, have
been implicated in a number of signal transduction pathways involved in
growth, development and defense responses of higher plants. This study
investigates the size range of OGAs capable of inducing ethylene synthesis
in tomato plants, and demonstrates that in contrast with many other
effects, only short chain OGAs are active. Oligomers across a range of DP
from 2-15 were separated and purified to homogeneity by QAE-Sephadex anion
exchange chromatography using a novel elution system. The OGAs were applied
to tomato plants and assayed for their ability to induce ethylene gas
release and changes in steady state levels of mRNA encoding the ethylene
forming enzyme aminocyclopropane-1-carboxylic acid oxidase (ACO). The study
demonstrated that only OGAs in the size range of DP4-6 were active both in
eliciting ACO expression and in the production of ethylene.
相似文献
133.
Christopher C Butler Stephen Rollnick Roisin Pill Frances Maggs-Rapport Nigel Stott 《BMJ (Clinical research ed.)》1998,317(7159):637-642
Objectives: To better understand reasons for antibiotics being prescribed for sore throats despite well known evidence that they are generally of little help. Design: Qualitative study with semi-structured interviews. Setting: General practices in South Wales. Subjects: 21 general practitioners and 17 of their patients who had recently consulted for a sore throat or upper respiratory tract infection. Main outcome measures: Subjects’ experience of management of the illness, patients’ expectations, beliefs about antibiotic treatment for sore throats, and ideas for reducing prescribing. Results: Doctors knew of the evidence for marginal effectiveness yet often prescribed for good relationships with patients. Possible patient benefit outweighed theoretical community risk from resistant bacteria. Most doctors found prescribing “against the evidence” uncomfortable and realised this probably increased workload. Explanations of the distinction between virus and bacterium often led to perceived confusion. Clinicians were divided on the value of leaflets and national campaigns, but several favoured patient empowerment for self care by other members of the primary care team. Patient expectations were seldom made explicit, and many were not met. A third of patients had a clear expectation for antibiotics, and mothers were more likely to accept non-antibiotic treatment for their children than for themselves. Satisfaction was not necessarily related to receiving antibiotics, with many seeking reassurance, further information, and pain relief. Conclusions: This prescribing decision is greatly influenced by considerations of the doctor-patient relationship. Consulting strategies that make patient expectations explicit without damaging relationships might reduce unwanted antibiotics. Repeating evidence for lack of effectiveness is unlikely to change doctors’ prescribing, but information about risk to individual patients might. Emphasising positive aspects of non-antibiotic treatment and lack of efficacy in general might be helpful.
Key messages
- Doctors know that antibiotics do not help most sore throat sufferers but try not to jeopardise relationships with patients over this issue
- Patients’ expectations are seldom explicit, and satisfaction is not necessarily related to receiving an antibiotic: information and reassurance are sometimes more important
- Consulting techniques that make expectations explicit, preserve relationships, and facilitate acceptable management are important
- Opportunities for empowering patients who are not acutely ill could be better used, and emphasising positive aspects of non-antibiotic treatment, especially in children, could be fruitful
- Risks to individuals from unnecessary antibiotics (rather than trial evidence for marginal benefit) should be emphasised
134.
135.
The thoracic appendicular skeletal development of five common marmosets was monitored radiographically at weekly intervals from 1 day to 94 weeks of age and the times of appearance and fusion of 47 ossification centers were recorded. A range and average age for the appearance and fusion of each ossification center were calculated and compared to data available for the rhesus monkey and man. 相似文献
136.
137.
A change in twist of actin provides the force for the extension of the acrosomal process in limulus sperm: the false-discharge reaction 总被引:6,自引:5,他引:1
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One of the most spectacular motions is the generation of the acrosomal process in the limulus sperm. On contact with the egg, the sperm generates a 60-mum-long process that literally drills its way through the jelly surrounding the egg. This irresversible reaction takes only a few seconds. We suggested earlier that this motion is driven by a change in twist of the actin filaments comprising the acrosomal process. In this paper we analyze the so-called false discharge, a reversible reaction, in which the acrosomal filament bundle extends laterally from the base of the sperm and not anteriorly from the apex. Unlike the true discharge, which is straight, the false discharge is helical. Before extension, the filament bundle is coiled about the base of the sperm. In the coil, the bundle is not smoothly bent but consists of arms (straight segments) and elbows (corners) so that the coil looks like a 14-sided polygon. The extension of the false discharge works as follows: starting at the base of the bundle, the filaments change their twist which concomitantly changes the orientations of the elbows relative to each other; that is, in the coil, the elbows all like in a common plane, but after the change in twist, the plane of each elbow is rotated to be perpendicular to that of its neighbors. This change transforms the bundle from a compact coil into an extended left- handed helix. Because the basal end of the bundle is unconstrained, the extension is lateral. The true discharge works the same way but starts at the apical end of the bundle. The apical end, however, is constrained by its passage through the nuclear canal, which directs the extention anteriorly. Unlike the false discharge, during the true discharge the elbows are melted out, making the reaction irreversible. This study shows that rapid movement can be regenerated by actin without myosin and gives us insight into the molecular mechanism. 相似文献
138.
The increasing use of wastewater for crop irrigation in arid and semi-arid zones means that wastewater parasitology is becoming on important research area. The World Health Organization's (WHO) current guideline states that only treated wastewater containing no more than one human intestinal nematode egg per litre should be used for irrigation. This guideline was based on very limited epidemiological evidence. In this article Rachel Ayres, Rebecca Stott, Duncan Mara and Donald Lee describe their recent work in Yorkshire and northeast Brazil and suggest that their results may be the first evidence for relaxing the WHO guideline for restricted irrigation to no more than ten intestinal nematode eggs per litre. 相似文献
139.
Burek KA Gulland FM Sheffield G Beckmen KB Keyes E Spraker TR Smith AW Skilling DE Evermann JF Stott JL Saliki JT Trites AW 《Journal of wildlife diseases》2005,41(3):512-524
Serologic data were examined to determine whether infectious disease may have played a role in the decline of Steller sea lions (Eumetopias jubatus) in the Gulf of Alaska and Aleutian Islands, USA. Available published data, unpublished data, and recent collections (1997-2000) were compared and reviewed. Data were stratified by geography to compare the declining western Alaskan population in the Aleutian Islands through eastern Prince William Sound to the increasing population in southeastern Alaska. Prevalences of antibodies from the 1970s to the early 1990s were noted for Leptospira interrogans, Chlamydophila psittaci, Brucella spp., phocid herpesvirus-1, and calciviruses. Serum samples collected from 1997-2000 were tested for antibodies to these agents as well as to marine mammal morbilliviruses, canine parvovirus, and canine adenovirus-1 and -2. Conclusions could not be drawn about changes in antibody prevalence to these agents during the decline of Steller sea lions, however, because data were incomplete or not comparable as a result of inconsistencies in testing techniques. Despite these shortcomings, results provided no convincing evidence of significant exposure of Steller sea lions to morbilliviruses, Brucella spp., canine parvovirus, or L. interrogans. Steller sea lions have been exposed to phocid herpesviruses, caliciviruses, canine adenovirus, and C. psittaci or to cross-reactive organisms in regions of both increasing and decreasing sea lion abundance. Based on similar antibody prevalence estimates from the increasing and decreasing populations, these agents are unlikely to have been the primary cause of the population decline. They may have contributed to the decline or impeded population recovery, however, because of undetected mortality and morbidity or reductions of fecundity and body condition in animals under other stresses. Systematic monitoring for disease agents and their effects is needed to determine whether infectious disease currently plays a role in the decline and lack of recovery of Steller sea lions. 相似文献
140.
Warren R Hsiao WW Kudo H Myhre M Dosanjh M Petrescu A Kobayashi H Shimizu S Miyauchi K Masai E Yang G Stott JM Schein JE Shin H Khattra J Smailus D Butterfield YS Siddiqui A Holt R Marra MA Jones SJ Mohn WW Brinkman FS Fukuda M Davies J Eltis LD 《Journal of bacteriology》2004,186(22):7783-7795
Rhodococcus sp. strain RHA1, a potent polychlorinated-biphenyl (PCB)-degrading strain, contains three linear plasmids ranging in size from 330 to 1,100 kb. As part of a genome sequencing project, we report here the complete sequence and characterization of the smallest and least-well-characterized of the RHA1 plasmids, pRHL3. The plasmid is an actinomycete invertron, containing large terminal inverted repeats with a tightly associated protein and a predicted open reading frame (ORF) that is similar to that of a mycobacterial rep gene. The pRHL3 plasmid has 300 putative genes, almost 21% of which are predicted to have a catabolic function. Most of these are organized into three clusters. One of the catabolic clusters was predicted to include limonene degradation genes. Consistent with this prediction, RHA1 grew on limonene, carveol, or carvone as the sole carbon source. The plasmid carries three cytochrome P450-encoding (CYP) genes, a finding consistent with the high number of CYP genes found in other actinomycetes. Two of the CYP genes appear to belong to novel families; the third belongs to CYP family 116 but appears to belong to a novel class based on the predicted domain structure of its reductase. Analyses indicate that pRHL3 also contains four putative "genomic islands" (likely to have been acquired by horizontal transfer), insertion sequence elements, 19 transposase genes, and a duplication that spans two ORFs. One of the genomic islands appears to encode resistance to heavy metals. The plasmid does not appear to contain any housekeeping genes. However, each of the three catabolic clusters contains related genes that appear to be involved in glucose metabolism. 相似文献