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61.
Bob Mash Di Powell Felicity du Plessis Unita van Vuuren Margaret Michalowska Naomi Levitt 《Suid-Afrikaanse tydskrif vir geneeskunde》2007,97(12):1284-1288
BACKGROUND AND AIMS: In South Africa diabetes makes a significant contribution to the burden of disease. Diabetic retinopathy is a leading cause of adult blindness, and screening can reduce the incidence. This project aimed to implement and evaluate a new service for retinal screening that uses a non-mydriatic mobile fundal camera in primary care. This is the first time such a service has been evaluated in an African primary care context. METHODS: The service was implemented as an operational research study at three community health centres and data were collected to evaluate the operational issues, screening, reporting and referral of patients. RESULTS: Out of 400 patients screened 84% had a significantly reduced visual acuity, 63% had retinopathy (22% severe nonproliferative, 6% proliferative and 15% maculopathy), 2% of eyes could not be screened and 14% of patients required dilatation. Referral was necessary in 27% of cases for cataracts, in 7% for laser treatment and in 4% for other specialist services. Repeat photography was needed in 8% and urgent follow-up in 12%. A SWOT analysis of the pilot project was completed and recommendations were made on how to integrate it into the district health system. CONCLUSION: Screening with a fundal camera improved the quality of care for diabetic patients and is feasible in the South African public sector, primary care setting. A single technician should be able to photograph almost 10,000 patients a year. 相似文献
62.
Novel C3 nephritic factor activity in the glomerulonephritis of staphylococcal endocarditis 总被引:1,自引:0,他引:1
C F Craddock N P Richards R J Powell A G Morgan 《The Quarterly journal of medicine》1987,65(247):895-898
A case of glomerulonephritis complicating staphylococcal endocarditis is presented. Hypocomplementaemia and a C3-activating factor in the serum suggested that the patient might have mesangiocapillary glomerulonephritis in association with C3-nephritic factor. Renal biopsy showed that this was not so and further examination of the serum factor showed that it differed from classical C3-nephritic factor because it was not an immunoglobulin. It is postulated that complement activation and glomerulonephritis in staphylococcal endocarditis may be the direct result of a bacterial product. A substance in the serum which activates C3 should be confirmed to be an immunoglobulin before the presence of classical C3-nephritic factor is assumed. 相似文献
63.
64.
Conway F. Saylor PhD Cynthia Cupit Swenson Ph.D. Paige Powell Ph.D. 《Child psychiatry and human development》1992,22(3):139-149
This article reports highlights from over 200 parents' observations of their preschoolers' play and verbalizations in the year following Hurricane Hugo. Commonly reported activities included reenactment and discussion of the event in multiple mediums, personification of Hugo, and expression of fears related to storms. Precocious concern for others, insight, and vocabulary were also noted. In these intact, relatively high functioning families, parents seemed able to facilitate their youngsters' adjustment without outside intervention.Portions of this report were presented in earlier form at the 1991 Society for Research in Child Development meeting in Seattle, Washington. 相似文献
65.
66.
Vassilios I. Avramis William C. Powell Robert A. Mecum 《Cancer chemotherapy and pharmacology》1989,25(1):19-24
Summary 1--d-arabinosyl-5-azacytosine (ara-AC) is a relatively new antitumor agent under clinical investigation, which has the 2- arabinosyl configuration found in the tumoricidal drug ara-C and the nitrogen substitution in the 5-position of the pyrimidine ring found in 5-azacytidine (5-aza-C). The present study examined the cellular metabolism and the effect on DNA methylation of ara-AC in human CCRF/CEM cells sensitive and resistant to ara-C. The triphosphate anabolite of the drug, ara-ACTP, was the major anabolite in the CEM cellular extracts, peaking at 50.6±23 M 4 h after incubation with IC50 concentrations (0.25 M) of [3H]ara-AC. The mono- and diphosphate anabolites accumulated 10-fold lower cellular concentrations than ara-ACTP. The nucleoside triphosphate (NTP) pools and, especially, cellular ATP declined significantly by 9 h after the initiation of drug treatment and remained depleted for the 24-h treatment. The drug anabolite was gradually incorporated into both RNA and DNA, peaking in CEM/0 at 3.44 and 0.14 nmol/107 cells, respectively. The DNA methylation levels in these cells declined rapidly after treatment with ara-AC, attaining a nadir plateau at 29% of control methylation value. The deoxycytidine kinase (dCk) mutant CEM cell line [CEM/dCk(–)] neither activated ara-AC at appreciable levels nor induced DNA hypomethylation at low concentrations (0.25–1 M). However, the drug was activated at 0.2–1 M extracellular concentrations of ara-AC, probably by an as yet unknown nucleoside kinase at approximately 10% of the amount in CEM/0 cells. Ara-AC appears to mediate its cytotoxic action through the accumulation of its triphosphate anabolite, ara-ACTP, and the subsequent incorporation into nucleic acids. DNA methylation may also contribute to its cytotoxicity.Abbreviations 5-aza-C
5-azacytidine
- ara-AC
1--d-arabinofuranosyl-5-azacytosine
- ara-ACTP
1--d-arabinofuranosyl-5-azacytosine 5-triphosphate
- dCk
deoxycytidine kinase
- PCA
perchloric acid
- SAX
strong anion exchange
- PBS
phosphate-buffered saline
Supported by research grant CA 38905 from the National Institute of Health, NCI, and the T. J. Martell Foundation for Leukemia and Cancer Research, The Neil Bogart Memorial Laboratories 相似文献
67.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
68.
69.
70.
R Whitley A Arvin C Prober S Burchett L Corey D Powell S Plotkin S Starr C Alford J Connor 《The New England journal of medicine》1991,324(7):444-449
BACKGROUND. Despite the use of vidarabine, herpes simplex virus (HSV) infection in neonates continues to be a disease of high morbidity and mortality. We undertook a controlled trial comparing vidarabine with acyclovir for the treatment of neonatal HSV infection. METHODS. Babies less than one month of age with virologically confirmed HSV infection were randomly and blindly assigned to receive either intravenous vidarabine (30 mg per kilogram of body weight per day; n = 95) or acyclovir (30 mg per kilogram per day; n = 107) for 10 days. Actuarial rates of mortality and morbidity among the survivors after one year were compared overall and according to the extent of the disease at entry into the study (infection confined to the skin, eyes, or mouth; encephalitis; or disseminated disease). RESULTS. After adjustment for differences between groups in the extent of disease, there was no difference between vidarabine and acyclovir in either morbidity (P = 0.83) or mortality (P = 0.27). None of the 85 babies with disease confined to the skin, eyes, or mouth died. Of the 31 babies in this group who were treated with vidarabine and followed for a year, 88 percent (22 of 25) were judged to be developing normally after one year, as compared with 98 percent (45 of 46) of the 54 treated with acyclovir (95 percent confidence interval for the difference, -4 to 24). For the 71 babies with encephalitis, mortality was 14 percent with vidarabine (5 of 36) and with acyclovir (5 of 35); of the survivors, 43 percent (13 of 30) and 29 percent (8 of 28), respectively, were developing normally after one year (95 percent confidence interval for the difference, -11 to 39). For the 46 babies with disseminated disease, mortality was 50 percent (14 of 28) with vidarabine and 61 percent (11 of 18) with acyclovir (95 percent confidence interval for the difference, -20 to 40); of the survivors, 58 percent (7 of 12) and 60 percent (3 of 5), respectively, were judged to be developing normally after one year (95 percent confidence interval for the difference, -40 to 50). Both medications were without serious toxic effects. CONCLUSIONS. In this multicenter, randomized, blinded study there were no differences in outcome between vidarabine and acyclovir in the treatment of neonatal HSV infection. The study lacked statistical power to determine whether there were sizable differences within the subgroups of those with localized HSV, encephalitis, or disseminated disease. 相似文献