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991.
《Endocrine practice》2023,29(8):606-611
ObjectiveDespite increased awareness, osteoporosis screening rates remain low. The objective of this survey study was to identify physician-reported barriers to osteoporosis screening.MethodsWe conducted a survey of 600 physician members of the Endocrine Society, American Academy of Family Practice, and American Geriatrics Society. The respondents were asked to rate barriers to osteoporosis screening in their patients. We performed multivariable logistic regression analyses to determine correlates with the most commonly reported barriers.ResultsOf 566 response-eligible physicians, 359 completed the survey (response rate, 63%). The most commonly reported barriers to osteoporosis screening included patient nonadherence (63%), physician concern about cost (56%), clinic visit time constraints (51%), low on the priority list (45%), and patient concern about cost (43%). Patient nonadherence as a barrier was correlated with physicians in academic tertiary centers (odds ratio [OR], 2.34; 95% confidence interval [CI], 1.06-5.13), whereas clinic visit time constraints were correlated with physicians in both community-based academic affiliates and academic tertiary care ([OR, 1.96; 95% CI, 1.10-3.50] and [OR, 2.48; 95% CI, 1.22-5.07], respectively). Geriatricians (OR, 0.40; 95% CI, 0.21-0.76) and physicians with >10 years in practice were less likely to report clinic visit time constraints as a barrier (11-20 years: OR, 0.41; 95% CI, 0.20-0.85; >20 years: OR, 0.32; 95% CI, 0.16-0.65). Physicians with more patient-facing time (3-5 compared with 0.5-2 d/wk) were more likely to place screening low on the priority list (OR, 2.66; 95% CI, 1.34-5.29).ConclusionUnderstanding barriers to osteoporosis screening is vital in developing strategies to improve osteoporosis care. 相似文献
992.
A recent increase in the abundance of cattails (Typha spp.) in North American wetlands has been anecdotally linked with hybridization between Typha latifolia and Typha angustifolia. In this study, we used molecular genetic markers (microsatellites) to investigate whether the hybrid lineage (Typha × glauca) is restricted to The Great Lakes region, or exists across a much broader spatial scale. We also investigated the possibility of backcrossing and genetic introgression in natural populations. Parental species could be distinguished from one another based on the distribution of alleles at six microsatellite loci. Species identification based on genetic data corresponded well with species identifications based on leaf width, a key morphological trait that can distinguish the two parental species. We found that hybrids occur in Ontario, Quebec, New Brunswick, and Nova Scotia, but we did not detect hybrids in Maine. F1s are more abundant than backcrossed or intercrossed hybrids, although we also found evidence of backcrossing, particularly in Ontario. This indicates that hybrids are fertile, and are therefore potential conduits of gene flow between the parental species. Further work is needed to determine whether T. × glauca is particularly successful in the Great Lakes region relative to other areas in which the two parental species co-exist, and to assess whether introgression may lead to increased invasiveness in the species complex. 相似文献
993.
994.
Y. X. Cui G. W. Xu C. W. Magill K. F. Schertz G. E. Hart 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,89(1):64-69
A sorghum genomic DNA clone that hybridized on Southern blots in simple but different patterns to fragments produced by digestion of DNA from the parents of an F2 mapping population was hybridized to EcoRV-digested DNA from 53 accessions. Forty-six different fragment patterns were observed, each comprised of from one to ten bands. Much less variability was detected in EcoRI than EcoRV digests of a selected subset of the accessions. Base-sequence analysis of the clone did not reveal a functional identity for the sequence and the clone does not contain repeated sequences often associated with hypervariable loci. Clones such as this will be especially useful in evaluating germplasm diversity and in identifying the potential parentage of hybrids. 相似文献
995.
996.
John M. Webster 《Journal of nematology》2012,44(2):107-114
Nathan Cobb, as the father figure of the Society of Nematologists, set an example to later generations of nematologists in his studies of nematode biology. In the 50 years of the Society’s existence nematological research has greatly expanded that knowledge base. Opportunities over the next 50 years are boundless in view of advancing technologies and emerging challenges, and this leads to speculation as to what future nematological research advances will enhance peoples’ quality of life. 相似文献
997.
BackgroundThe present study assesses the time intervals from symptom discovery to treatment start and describes the health service use experiences of uninsured patients with cancer of the breast, cervix uteri, testicle, and prostate before their arrival to the cancer hospital.MethodsThis cross-sectional study included 1468 patients who were diagnosed between June 2016 and May 2017 and received treatment for the selected cancers in two of the largest public cancer hospitals in Mexico City, financed through Seguro Popular. Data was collected through a survey administered via face-to-face interviews with patients and a review of their medical files.ResultsThe median time between detection (symptom discovery or first abnormal screening test) and treatment start was 6.6 months. For all types of cancer, the longest interval was the diagnostic interval –between the first use of healthcare services and the confirmation of cancer. Less than 20% cancer patients were diagnosed in the earliest stages that are associated with the best chances of long-term survival. The participants described a high use of private services for their first consultation, the use of several different types of health services and multiple consultations before arrival to the cancer centers, and 35% perceived being misdiagnosed by the first doctor they consulted.ConclusionsMost cancer patients treated in the two largest public institutions available for the uninsured faced long delays to get diagnosed and started treatment at advanced stages. Strengthening quality and access for effective early cancer diagnosis and treatment is key to improve patient outcomes in low and middle-income settings. 相似文献
998.
LAWRENCE R. HEANEY ROBERT M. TIMM 《Biological journal of the Linnean Society. Linnean Society of London》1985,25(4):301-317
A population of hybrid pocket gophers ( Geomys bursarius × G. lutescens ) exists 1–2 km west of Oakdale, Antelope County, Nebraska, U.S.A. The hybrids occur in soil that has characteristics intermediate between that occupied by G. lutescens (sand) and by G. bursarius (silt loam); the vegetation associations on the different soils are Sandhills Prairie and Tall-grass Prairie, respectively, with mixed prairie on the intermediate soils. Hybrids are identifiable on the basis of both qualitative and quantitative morphological characteristics, allozymes and karyology. Concordance between morphological, allozymic, karyotypic and ecological data sets is very high. Hybrids appear to reproduce normally and survive well; i.e. they suffer no obvious loss of fitness. Backcrossing to either parental type is apparently rare. The parental species each support obligate parasitic lice ( Geomydoecus : Trichodectidae) of different species; these species are not sister species. We suggest that hybrid zones resulting from primary and secondary contact may be distinguished by (1) concordance of clines in different character sets, (2) fossil and biogeographic data, and (3) parasite data. We conclude that this zone resulted from secondary contact, and that the zone is maintained either by selection against hybrids (less likely) or by hybrid superiority (more likely). 相似文献
999.
Extensive land clearing in many parts of the global tropics is a major threat to biodiversity, and strategies are urgently needed to reinstate forest. Tree planting is a commonly used strategy to rapidly restore forest to degraded landscapes. However, tree planting is expensive, and in most cases financial constraints prevent its use at a scale needed to address the ongoing legacy of land clearing. Here, we conduct a quantitative review of literature from the global tropics and evaluate outcomes of less intensive interventions (i.e. non‐planting) aimed at stimulating natural regeneration of forest. We focus specifically on overcoming barriers to native plant regeneration that predominate in the earliest stages of succession. Common interventions include varied strategies to suppress herbaceous vegetation (e.g. cutting or herbicide treatment), and measures to bolster propagule supply (e.g. direct seeding and artificial bird perches). There was an apparent trend among pair‐wise comparisons of effect sizes to suggest that combined interventions to simultaneously suppress herbaceous vegetation and increase propagule supply resulted in the most consistent outcomes in terms of promoting progress toward restoring forest structure. Despite an obvious demand for lower cost interventions, a paucity of information means that it is still premature to generalize outcomes of specific interventions and their overall cost relative to active tree planting. Nevertheless, we report an increase in research effort in this area, and suggest promising directions to accelerate progress that will improve capacity to select optimal, cost effective strategies that achieve long‐term restoration objectives with a particular level of certainty . 相似文献
1000.
A detailed method is presented tor the creation of head-to-tail multimers of short blunt restriction fragments, ligaled into
a plasmid vector in a singletube: reaction. Random priming of the concatemer insert readily yields hybridization probes of
high specificity, unattainable from the short monomer fragments. 相似文献