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41.
42.
Objectives
Efforts to scale-up maternal and child health services in lower and middle income countries will fail if services delivered are not of good quality. Although there is evidence of strategies to increase the quality of health services, less is known about the way these strategies affect health system goals and outcomes. We conducted a systematic review of the literature to examine this relationship.Methods
We undertook a search of MEDLINE, SCOPUS and CINAHL databases, limiting the results to studies including strategies specifically aimed at improving quality that also reported a measure of quality and at least one indicator related to health system outcomes. Variation in study methodologies prevented further quantitative analysis; instead we present a narrative review of the evidence.Findings
Methodologically, the quality of evidence was poor, and dominated by studies of individual facilities. Studies relied heavily on service utilisation as a measure of strategy success, which did not always correspond to improved quality. The majority of studies targeted the competency of staff and adequacy of facilities. No strategies addressed distribution systems, public-private partnership or equity. Key themes identified were the conflict between perceptions of patients and clinical measures of quality and the need for holistic approaches to health system interventions.Conclusion
Existing evidence linking quality improvement strategies to improved MNCH outcomes is extremely limited. Future research would benefit from the inclusion of more appropriate indicators and additional focus on non-facility determinants of health service quality such as health policy, supply distribution, community acceptability and equity of care. 相似文献43.
CCL18 has been reported to be present constitutively at high levels in the circulation, and is further elevated during inflammatory diseases. Since it is a rather poor chemoattractant, we wondered if it may have a regulatory role. CCL18 has been reported to inhibit cellular recruitment mediated by CCR3, and we have shown that whilst it is a competitive functional antagonist as assessed by Schild plot analysis, it only binds to a subset of CCR3 receptor populations. We have extended this inhibitory activity to other receptors and have shown that CCL18 is able to inhibit CCR1, CCR2, CCR4 and CCR5 mediated chemotaxis, but has no effect on CCR7 and CCR9, nor the CXC receptors that we have tested. Whilst CCL18 is able to bind to CCR3, it does not bind to the other receptors that it inhibits. We therefore tested the hypothesis that it may displace glycosaminoglycan (GAG) chemokines bound either in cis- on the leukocyte, or in trans-presentation on the endothelial surface, thereby inhibiting the recruitment of leukocytes into the site of inflammation. We show that CCL18 selectivity displaces heparin bound chemokines, and that chemokines from all four chemokine sub-classes displace cell bound CCL18. We propose that CCL18 has regulatory properties inhibiting chemokine function when GAG-mediated presentation plays a role in receptor activation. 相似文献
44.
Jenny McLeish Rob A. Briers Jennifer A. Dodd Sonja Rueckert 《Journal of fish biology》2020,96(3):617-630
The European bullhead (Cottus gobio) is widely distributed across Europe, and within the UK is native to England and Wales, where it is protected under the Habitats Directive. In Scotland, however, the species is considered invasive and thriving populations are recorded in the Forth and Clyde river catchments, and the Ale Water in the Scottish Borders. The genetic identity of the Scottish populations has not been established. There is also debate about the status of the European bullhead and its validity as single species, a species complex with several unresolved species, or distinct different species in its European distribution range. There is therefore a need to determine the taxonomy and likely source of the novel Scottish populations. Genetic analyses using cytochrome oxidase 1 (COI) mitochondrial DNA sequences were undertaken on specimens from the Forth and Clyde catchments, and combined with the results of morphological characteristics to provide a comprehensive assessment of the taxonomic classification for Scottish bullheads. There was considerable variation in morphological characteristics between populations within Scotland and a wider range of variability than previously recorded for English populations. Genetically the Scottish populations were very closely related to English specimens, supporting the hypothesis of introduction directly from England to Scotland. In terms of broader relationships, Scottish specimens are genetically more closely related to the ostensible species Chabot fluviatile Cottus perifretum, which has been suggested as one of a complex of species across Europe. Morphologically they exhibit characteristics on the spectrum between C. perifretum and C. gobio. There is an urgent need for the clarification of the taxonomy of Cottus sp(p). to avoid confusion in future publications, legislation and management practices relating to bullheads throughout the UK and Europe. 相似文献
45.
46.
Barbara Cheney Paul M. Thompson Simon N. Ingram Philip S. Hammond Peter T. Stevick John W. Durban Ross M. Culloch Simon H. Elwen Laura Mandleberg Vincent M. Janik Nicola J. Quick Valentina ISLAS‐Villanueva Kevin P. Robinson Marina Costa Sonja M. Eisfeld Alice Walters Charlie Phillips Caroline R. Weir Peter G.H. Evans Pia Anderwald Robert J. Reid James B. Reid Ben Wilson 《Mammal Review》2013,43(1):71-88
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47.
Sonja Mertsch Patrick Oellers Michael Wendling Werner Stracke Solon Thanos 《Molecular neurobiology》2013,48(1):169-179
A hallmark of gliomas is the growth and migration of cells over long distances within the brain and proliferation within selected niches, indicating that the migrating cells navigate between complex substrates. We demonstrate in the present study a differential preference for migration that depends on Rho-associated coil kinase (ROCK) signaling, using the alternating Bonhoeffer stripe assay. Membrane fractions from nonmyelinated and myelinated brain areas from female rats, purified myelin also from female rats, and commercial extracellular matrix were used as substrates, with each substrate being tested against the others. The human tumor cell lines exhibited a clear preference for extracellular matrix over all other substrates and for myelinated over nonmyelinated tissue. ROCK signaling was different when cells were cultured on either substrate. The ROCK inhibitor Y27632 significantly attenuated and neutralized the preference for extracellular matrix and myelin, indicating that ROCK controls the substrate selectivity. The findings of this study pave the way for navigation-targeted therapeutics. 相似文献
48.
Sonja Langmesser 《Chronobiology international》2013,30(1-2):151-157
A functional circadian clock has long been considered a selective advantage. Accumulating evidence shows that the clock coordinates a variety of physiological processes in order to schedule them to the optimal time of day and thus to synchronize metabolism to changes in external conditions. In mitochondria, both metabolic and cellular defense mechanisms are carefully regulated. Abnormal clock function, might influence mitochondrial function, resulting in decreased fitness of an organism. 相似文献
49.
Jovana Milanovic Sonja Schiehser Predrag Milanovic Antje Potthast Mirjana Kostic 《Carbohydrate polymers》2013
The effects of TEMPO-mediated oxidation, performed with NaClO, a catalytic amount of NaBr, and 2,2′,6,6′-tetramethylpiperidine-1-oxy radical (TEMPO), were studied on lyocell fibers by means of GPC using multiple detection and group-selective fluorescence labeling according to the CCOA and FDAM methodology. The applied method determines functional group content as a sum parameter, as well as functional group profiles in relation to the molecular weight of the cellulose fibers. Both the CHO and COOH profiles, as well as molecular weight alterations, were analyzed. A significant decrease in the average molecular weight was obtained during the first hour of TEMPO-mediated oxidation, but prolonged oxidation time resulted in no strong additional chain scission. Significant amounts of COOH groups were introduced in the high molecular weight fractions by the oxidation with higher concentrations of NaClO (2.42–9.67 mmol NaClO/g fiber) after modification times of 1 h or longer. 相似文献
50.
Sonja Sucic Florian Koban Ali El-Kasaby Oliver Kudlacek Thomas Stockner Harald H. Sitte Michael Freissmuth 《The Journal of biological chemistry》2013,288(8):5330-5341
The serotonin transporter (SERT) maintains serotonergic neurotransmission via rapid reuptake of serotonin from the synaptic cleft. SERT relies exclusively on the coat protein complex II component SEC24C for endoplasmic reticulum (ER) export. The closely related transporters for noradrenaline and dopamine depend on SEC24D. Here, we show that discrimination between SEC24C and SEC24D is specified by the residue at position +2 downstream from the ER export motif (607RI608 in SERT). Substituting Lys610 with tyrosine, the corresponding residue found in the noradrenaline and dopamine transporters, switched the SEC24 isoform preference: SERT-K610Y relied solely on SEC24D to reach the cell surface. This analysis was extended to other SLC6 (solute carrier 6) transporter family members: siRNA-dependent depletion of SEC24C, but not of SEC24D, reduced surface levels of the glycine transporter-1a, the betaine/GABA transporter and the GABA transporter-4. Experiments with dominant negative versions of SEC24C and SEC24D recapitulated these findings. We also verified that the presence of two ER export motifs (in concatemers of SERT and GABA transporter-1) supported recruitment of both SEC24C and SEC24D. To the best of our knowledge, this is the first report to document a change in SEC24 specificity by mutation of a single residue in the client protein. Our observations allowed for deducing a rule for SLC6 family members: a hydrophobic residue (Tyr or Val) in the +2 position specifies interaction with SEC24D, and a hydrophilic residue (Lys, Asn, or Gln) recruits SEC24C. Variations in SEC24C are linked to neuropsychiatric disorders. The present findings provide a mechanistic explanation. Variations in SEC24C may translate into distinct surface levels of neurotransmitter transporters. 相似文献