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131.
N Kolehmainen G Maclennan L Ternent EA Duncan EM Duncan SB Ryan L McKee JJ Francis 《Implementation science : IS》2012,7(1):76
ABSTRACT: BACKGROUND: Access and equity in children's therapy services may be improved by directing clinicians' use of resources toward specific goals that are important to patients. A practice-change intervention (titled 'Good Goals') was designed to achieve this. This study investigated uptake, adoption, and possible effects of at intervention in children's occupational therapy services. METHODS: Mixed methods case studies (n = 3 services, including 46 therapists and 558 children) were conducted. The intervention was delivered over 25 weeks through face-to-face training, team workbooks, and 'tools for change'. Data were collected before, during, and after the intervention on a range of factors using interviews, a focus group, case note analysis, routine data, document analysis, and researchers' observations. RESULTS: Factors related to uptake and adoptions were: mode of intervention delivery, competing demands on therapists' time, and leadership by service manager. Service managers and therapists reported that the intervention: helped therapists establish a shared rationale for clinical decisions; increased clarity in service provision; and improved interactions with families and schools. During the study period, therapists' behaviours changed: identifying goals, odds ratio 2.4 (95% CI 1.5 to 3.8); agreeing goals, 3.5 (2.4 to 5.1); evaluating progress, 2.0 (1.1 to 3.5). Children's LoT decreased by two months [95% CI [MINUS SIGN]8 to +4 months] across the services. Cost per therapist trained ranged from [POUND SIGN]1,003 to [POUND SIGN]1,277, depending upon service size and therapists' salary bands. CONCLUSIONS: Good Goals is a promising quality improvement intervention that can be delivered and adopted in practice and may have benefits. Further research is required to evaluate its: (i) impact on patient outcomes, effectiveness, cost-effectiveness, and (ii) transferability to other clinical contexts. 相似文献
132.
Changes in noradrenergic vesicle markers of rabbit oviducts during progesterone treatment 总被引:1,自引:0,他引:1
The effect of progesterone (P) on norepinephrine (NE), [3H] norepinephrine ([3H]NE) and dopamine beta-hydroxylase (DBH) in noradrenergic vesicles from rabbit oviducts was studied after daily injections of the hormone during different periods (4, 7 and 15 days). Progesterone induced a concomitant increase in NE and DBH activity and [3H]NE uptake. To study the mechanism involved in such effects, 4 tissue fractions were obtained by differential centrifugation of the oviducts of which the vesicular fraction was applied over continuous sucrose gradients (0.3-2 M). The changes induced by P in markers of tissue and gradient fractions showed an increase of the NE storage capacity which could be ascribed to an increase in the number of storage vesicles, and/or to a higher extravesicular storage capacity. The occurrence of these mechanisms during pregnancy or after P treatment could account for the (long-lasting) high levels of NE observed in such instances. 相似文献
133.
Jeffrey T. Lell Michael D. Brown Theodore G. Schurr R. I. Sukernik Yelena B. Starikovskaya Antonio Torroni Lorna G. Moore Gary M. Troup D. C. Wallace 《Human genetics》1997,100(5-6):536-543
We have initiated a study of ancient male migrations from Siberia to the Americas using Y chromosome polymorphisms. The first
polymorphism examined, a C→T transition at nucleotide position 181 of the DYS199 locus, was previously reported only in Native
American populations. To investigate the origin of this DYS199 polymorphism, we screened Y chromosomes from a number of Siberian,
Asian, and Native American populations for this and other markers. This survey detected the T allele in all five Native American
populations studied at an average frequency of 61%, and in two of nine native Siberian populations, the Siberian Eskimo (21%)
and the Chukchi (17%). This finding suggested that the DYS199 T allele may have originated in Beringia and was then spread
throughout the New World by the founding populations of the major subgroups of modern Native Americans. We further characterized
Native American Y chromosome variation by analyzing two additional Y chromosome polymorphisms, the DYS287 Y Alu polymorphic (YAP) element insertion and a YAP-associated A→G transition at DYS271, both commonly found in Africans. We found
neither African allele associated with the DYS199 T allele in any of the Native American or native Siberian populations. However,
we did find DYS287 YAP+ individuals who harbored the DYS199 C allele in one Native American population, the Mixe, and in one
Asian group, the Tibetans. A correlation of these Y chromosome alleles in Native Americans with those of the DYS1 locus, as
detected by the p49a/p49f (p49a,f) probes on TaqI-digested genomic DNA, revealed a complete association of DYS1 alleles (p49a,f haplotypes) 13, 18, 66, 67 and 69 with the
DYS199 T allele, while DYS1 alleles 8 and 63 were associated with both the DYS199 C and T allele.
Received: 18 November 1996 / Accepted: 19 May 1997 相似文献
134.
135.
Michael P. Challen Timothy J. Elliott Ursula Kües Lorna A. Casselton 《Molecular & general genetics : MGG》1993,241(3-4):474-478
The A mating factor of Coprinus cinereus determines compatibility in mating by regulating part of a developmental sequence that leads to dikaryon formation. The A genes that trigger development encode two different classes of homeodomain proteins, and for a successful mating, a protein of one class, HD 1, must interact with a protein of the other class, HD 2. In this report we show that C. cinereus A genes that encode HD 2 proteins, a2-1 and b2-1, can elicit A-regulated development in the heterologous host C. bilanatus. Transformation rates were very low, suggesting that the genes were poorly transcribed. The fact that the HD 2 genes are functionally expressed implies successful heteromultimeric association of putative DNA-binding proteins coded by the two Coprinus species. This interaction was sufficient to satisfy the need for different A factors in the formation of a fertile C. bilanatus dikaryon, but fertile dikaryons were more readily produced in matings with the a2-1 gene transformants. The C. cinereus A genes, b1-1 and d1-1, which encode HD1 proteins, were either not expressed or their proteins were non-functional in C. bilanatus. These experiments raise some interesting questions regarding HD1–HD2 protein interactions. 相似文献
136.
137.
Formation of strand breaks in the DNA ofγ-irradiated chromatin 总被引:1,自引:0,他引:1
Summary Strand breaks have been determined by sedimentation on sucrose gradients in the DNA of chromatin irradiated after isolation from Chinese hamster lung fibroblasts. The yields of double-strand and single-strand breaks are similar to those found in the DNA of irradiated mammalian cells. Irradiation of isolated chromatin in the presence of the radical scavenger tertiary butanol indicates that at least 65% of single-strand breaks and 56% of double-strand breaks can be attributed to the action of hydroxyl radicals. The results indicate the influence of chromosomal proteins in modifying radiation damage to DNA and suggest that the mechanisms for the induction of strand breaks in the DNA of isolated chromatin may be comparable to those operating in the intact cell. 相似文献
138.
Miletti-González KE Murphy K Kumaran MN Ravindranath AK Wernyj RP Kaur S Miles GD Lim E Chan R Chekmareva M Heller DS Foran D Chen W Reiss M Bandera EV Scotto K Rodríguez-Rodríguez L 《The Journal of biological chemistry》2012,287(23):18995-19007
CD44 is a multifunctional cell receptor that conveys a cancer phenotype, regulates macrophage inflammatory gene expression and vascular gene activation in proatherogenic environments, and is also a marker of many cancer stem cells. CD44 undergoes sequential proteolytic cleavages that produce an intracytoplasmic domain called CD44-ICD. However, the role of CD44-ICD in cell function is unknown. We take a major step toward the elucidation of the CD44-ICD function by using a CD44-ICD-specific antibody, a modification of a ChIP assay to detect small molecules, and extensive computational analysis. We show that CD44-ICD translocates into the nucleus, where it then binds to a novel DNA consensus sequence in the promoter region of the MMP-9 gene to regulate its expression. We also show that the expression of many other genes that contain this novel response element in their promoters is up- or down-regulated by CD44-ICD. Furthermore, hypoxia-inducible factor-1α (Hif1α)-responsive genes also have the CD44-ICD consensus sequence and respond to CD44-ICD induction under normoxic conditions and therefore independent of Hif1α expression. Additionally, CD44-ICD early responsive genes encode for critical enzymes in the glycolytic pathway, revealing how CD44 could be a gatekeeper of the Warburg effect (aerobic glycolysis) in cancer cells and possibly cancer stem cells. The link of CD44 to metabolism is novel and opens a new area of research not previously considered, particularly in the study of obesity and cancer. In summary, our results finally give a function to the CD44-ICD and will accelerate the study of the regulation of many CD44-dependent genes. 相似文献
139.
Microbial community structure in soils with decomposing residues from plants with genetic modifications to lignin biosynthesis 总被引:2,自引:0,他引:2
Lignin is a major determinant of the decomposition of plant materials in soils. Advances in transgenic technology have led to the possibility of modifying lignin to improve the pulping properties of plant materials for papermaking. Previous studies have shown that lignin modifications also affect the rate of plant material decay in soil. The aim of this work was to investigate short-term changes in soil microbial community structures when tobacco residues with reduced activity of enzymes in the monolignol pathway decompose. The residues from lignin-modified plants all decomposed faster than unmodified plant materials. The relative proportions of some of the structural groups of microbial phospholipid fatty acids were affected by genetic modifications, especially the proportion of double unsaturated chain fatty acids, indicative of fungi. 相似文献
140.
Conformational changes due to externally applied physiochemical parameters, including pH, temperature, solvent composition, and mechanical forces, have been extensively reported for numerous proteins. However, investigations on the effect of fluid shear flow on protein conformation remain inconclusive despite its importance not only in the research of protein dynamics but also for biotechnology applications where processes such as pumping, filtration, and mixing may expose protein solutions to changes in protein structure. By combining particle image velocimetry and Raman spectroscopy, we have successfully monitored reversible, shear-induced structural changes of lysozyme in well-characterized flows. Shearing of lysozyme in water altered the protein's backbone structure, whereas similar shear rates in glycerol solution affected the solvent exposure of side-chain residues located toward the exterior of the lysozyme α-domain. The results demonstrate the importance of measuring conformational changes in situ and of quantifying fluid stresses by the three-dimensional shear tensor to establish reversible unfolding or misfolding transitions occurring due to flow exposure. 相似文献