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911.
912.
913.
Lisa M. Puchalski Ritchie Monique van Lettow Austine Makwakwa Adrienne K. Chan Jemila S. Hamid Harry Kawonga Alexandra L. C. Martiniuk Michael J. Schull Vanessa van Schoor Merrick Zwarenstein Jan Barnsley Sharon E. Straus 《Trials》2016,17(1)
BackgroundDespite availability of effective treatment, tuberculosis (TB) remains an important cause of morbidity and mortality globally, with low- and middle-income countries most affected. In many such settings, including Malawi, the high burden of disease and severe shortage of skilled healthcare workers has led to task-shifting of outpatient TB care to lay health workers (LHWs). LHWs improve access to healthcare and some outcomes, including TB completion rates, but lack of training and supervision limit their impact. The goals of this study are to improve TB care provided by LHWs in Malawi by refining, implementing, and evaluating a knowledge translation strategy designed to address a recognized gap in LHWs’ TB and job-specific knowledge and, through this, to improve patient outcomes.Methods/designWe are employing a mixed-methods design that includes a pragmatic cluster randomized controlled trial and a process evaluation using qualitative methods. Trial participants will include all health centers providing TB care in four districts in the South East Zone of Malawi. The intervention employs educational outreach, a point-of-care reminder tool, and a peer support network. The primary outcome is proportion of treatment successes, defined as the total of TB patients cured or completing treatment, with outcomes taken from Ministry of Health treatment records. With an alpha of 0.05, power of 0.80, a baseline treatment success of 0.80, intraclass correlation coefficient of 0.1 based on our pilot study, and an estimated 100 clusters (health centers providing TB care), a minimum of 6 patients per cluster is required to detect a clinically significant 0.10 increase in the proportion of treatment successes. Our process evaluation will include interviews with LHWs and patients, and a document analysis of LHW training logs, quarterly peer trainer meetings, and mentorship meeting notes. An estimated 10–15 LHWs and 10–15 patients will be required to reach saturation in each of 2 planned interview periods, for a total of 40–60 interview participants.DiscussionThis study will directly inform the efforts of knowledge users within TB care and, through extension of the approach, other areas of care provided by LHWs in Malawi and other low- and middle-income countries.
Trial registration
ClinicalTrials.gov . Registered 20 August 2015. Protocol Date/Version 29 May 2016/Version 2. NCT02533089Electronic supplementary material
The online version of this article (doi:10.1186/s13063-016-1563-2) contains supplementary material, which is available to authorized users. 相似文献914.
915.
Cerium-based methods have been used for the demonstration of seve phatases at alkaline, acid and neutral pH in low temperature acetone-fixed, plastic-e sections. At alkaline pH calcium is used as capturing agent and the precipitated phosphate converted to cerium phosphate. At neutral and acid pH cerium is used d capturing agent. Cerium phosphate is subsequently visualized using the H2C2DAB n: comparison has been made with conventional calcium-cobalt and lead methods. It; that calcium-cobalt methods are more susceptible to improvement than lead methods 相似文献
916.
M L Hutchinson D S Schultz R A Stephenson K L Wong T Harry D J Zahniser 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》1989,11(2):105-110
Computerized image analysis was employed to analyze fine needle aspiration smears of the prostate and breast using both high-resolution images of individual cells and medium-resolution images of scenes and clusters (contextual analysis). A linear discriminant analysis was used to demonstrate the computer's ability to discriminate between benign and malignant categories for both types of tissue. Correct classification as benign or malignant using contextual analysis was achieved in 22 of 26 prostatic aspirates and in 15 of 18 breast aspirates, as determined by comparison with histology. The addition of high-resolution single-cell analysis resulted in correct classification of 24 of 26 prostatic aspirates and all breast aspirates. For virtually all features, the distinction between benign and malignant was more subtle for prostatic than for breast tissue. The data indicate that contextual analysis may be less effective as an adjunct to high-resolution single-cell microscopy of prostatic specimens than it is for breast specimens. 相似文献
917.
Tellurium-Induced Neuropathy: Metabolic Alterations Associated with Demyelination and Remyelination in Rat Sciatic Nerve 总被引:3,自引:2,他引:1
G. J. Harry J. F. Goodrum† T. W. Bouldin† M. Wagner-Recio‡ A. D. Toews‡ P. Morell‡ 《Journal of neurochemistry》1989,52(3):938-945
Rats fed a diet containing 1.25% elemental tellurium initiated on postnatal day 20 undergo a transient neuropathy characterized by synchronous demyelination of peripheral nerves. In sciatic nerve, the extent of demyelination was maximal after 5 days of tellurium exposure; there was a loss of 25% of the myelin, as assayed by concentration of myelin-specific P0 protein. Tellurium-induced alterations in the metabolic capacity of Schwann cells were examined by measuring the synthesis of myelin lipids in vitro in isolated sciatic nerve segments. Exposure to tellurium resulted in an early marked decrease of approximately 50% in overall incorporation of [14C]acetate into lipids, with a preferential depression in synthesis of cerebrosides, cholesterol, and ethanolamine plasmalogens (components enriched in myelin). Most dramatically, within 1 day of initiation of tellurium exposure, there was a profound increase in [14C]acetate-derived radioactivity in squalene; 23% of incorporated label was in this intermediate of cholesterol biosynthesis, compared to less than 0.5% in controls. In association with the remyelinating phase seen after 5 days of tellurium exposure, synthesis of myelin components gradually returned to normal levels. After 30 days, metabolic and morphologic alterations were no longer apparent. We suggest that the sequence of metabolic events in sciatic nerve following tellurium treatment initially involves inhibition of the conversion of squalene to 2,3-epoxysqualene, and that this block in the cholesterol biosynthesis pathway results, either directly or indirectly, in the inhibition of the synthesis of myelin components and breakdown of myelin. 相似文献
918.
919.
Harry Cuppens Eric egius Pablo Cabello Peter Marynen Chris De Boeck Ronny Decorte Jean-Pierre Fryns Ephraim Eggermont Herman Van den Berghe Jean-Jacques Cassiman 《Human genetics》1990,85(4):402-403
Summary Using Southern blotting and the polymerase chain reaction, the prevalence of the haplotypes for XV2c, CS7, KM19 and D9 on
CF and on normal chromosomes could be determined in 35 Belgian families. A set of primers complementary to the DNA sequence
of the CF gene around the ΔF508 deletion was used to amplify this particular segment of the gene. In a total of 57 families,
deletion screening showed that 69 out of 116 CF chromosomes (59.5%) carried the ΔF508 deletion. Both the ΔF508 deletion and
another mutation(s) showed strong association with the haplotype 1-2-2-2. 相似文献
920.
J. Gregory McKinnon Shelley K. Hoover Thomas H. Inge Harry D. Bear 《Cancer immunology, immunotherapy : CII》1990,32(1):38-44
Summary Large numbers of cytotoxic T lymphocytes (CTL) could be generated from tumor-draining lymph nodes (DLN) from mice bearing PHS-5 tumor by culturing at low density with autologous tumor cell stimulators and 20 U/ml recombinant interleukin-2 (IL-2). Outgrowth of metastatic tumor cells in culture was prevented by use of this hypoxanthine/aminopterin/thymidine-sensitive mutant of P815, PHS-5. After 9 days in culture, lymphoid cells demonstrated specific cytotoxicity against autologous tumor target cells. Lymph node cells could be expanded continuously in culture with repeated tumor stimulation with up to 7500-fold increase in cell number by 6 weeks; although CTL could be activated from tumor-bearing host spleen cells in short-term culture, they showed no significant growth in long-term cultures. Phenotypically, DLN cells were a mixture of CD8+ and CD4+ cells immediately after harvest but after 2 weeks in culture they were predominantly CD8+ CD4–. CTL could be generated from tumor-bearing mice 10–14 days after i.d. tumor inoculation into the abdominal wall, but the immune response declined both in spleen and DLN by 21 days. Much greater CTL activity could be generated from axillary DLN that contained metastases than from non-draining popliteal nodes that were free of metastatic tumor cells. Some CTL activity could be generated from DLN with the addition of IL-2 alone but was further increased by the addition of more tumor cells as stimulators. When adoptively transferred to a host with 3-day P815 liver metastases, lymphocytes from DLN activated in vitro were able to reduce or eliminate metastases with very little or no IL-2 administered concomitantly. As few as 106 cells were therapeutically effective, and in vivo efficacy was tumor-specific, since L5178Y liver metastases were not affected.This work was supported in part by grants CA42443, CA48075 and T32-CA09210 from the National Cancer Institute, Department of Health and Human ServicesRecipient of the Canadian Cancer Society McEachern Fellowship. 相似文献