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Ades AE, Walker J, Botting B, Parker S, Cubitt D, Jones R. Effect of the worldwide epidemic on HIV prevalence in the United Kingdom: record linkage in anonymous neonatal seroprevalence surveys. AIDS 1999; 13:2437-43. [PMID: 10597786 DOI: 10.1097/00002030-199912030-00016] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE To assess the impact of the worldwide HIV/AIDS epidemic on the prevalence of HIV in women in the United Kingdom (UK), particularly in the large immigrant and ethnic minority communities. METHOD Unlinked anonymous neonatal seroprevalence survey with electronic record linkage of data from child health computers (maternal age and ethnic status) and birth registration (parent's country of birth). RESULTS Of a total 137456 samples collected in 1997-1998, 188 (0.14%) were anti-HIV-1 seropositive. Seroprevalence was highest in women born in East Africa (2.3%) and Central Africa (1.9%). 76.4% of seropositive newborns were delivered to mothers born in sub-Saharan Africa; a further 6.0% had fathers from sub-Saharan Africa. However, there was little evidence of HIV in women born in Southern Asia [prevalence 0.0081%; 95% confidence interval (CI) 0-0.04], and none within UK-born Asian communities. Prevalence among the UK-born Black African community was low (0.14%; 95% CI 0-0.6). Among infants with both parents known to be born in the UK, seroprevalence was 0.023% (95% CI 0.01-0.04) in London, and zero (95% CI 0-0.007) in non-Metropolitan areas. Irrespective of mother's region of birth, seroprevalence was 4.2 times higher (95% CI 3.0-5.8) in newborns whose father's details were not recorded at birth registration, a marker for single unsupported mothers. CONCLUSION The risk of HIV among pregnant women from sub-Saharan Africa has been recognized. However, in southern England, HIV is very rare in women from Southern Asia and in UK-born women in ethnic minority communities, in spite of cultural and travel ties to high-prevalence countries. Data linkage in anonymous surveys assists in monitoring the impact of the worldwide epidemic on prevalence and incidence locally.
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Cohen MB, Giannella RA, Losonsky GA, Lang DR, Parker S, Hawkins JA, Gunther C, Schiff GA. Validation and characterization of a human volunteer challenge model for cholera by using frozen bacteria of the new Vibrio cholerae epidemic serotype, O139. Infect Immun 1999; 67:6346-9. [PMID: 10569748 PMCID: PMC97040 DOI: 10.1128/iai.67.12.6346-6349.1999] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Until recently, all epidemic strains of Vibrio cholerae were of the O1 serotype. Current epidemics have also been caused by a new serotype, Vibrio cholerae O139. Although the pathogenesis and clinical features of O139 cholera are similar to those of O1 cholera, immunity to serotype O1 does not confer immunity to serotype O139. Therefore, prior to beginning vaccine efficacy studies, we sought to validate the use of a large standardized frozen inoculum of virulent V. cholerae O139 4260B for use in a human volunteer challenge model. Healthy volunteers (n = 25) were recruited for an Internal Review Board-approved inpatient dose-escalation challenge. Our goal was to identify a dose at which the cholera attack rate and the geometric mean purge were sufficient for determining vaccine efficacy against moderate and severe disease. At a dose of 10(5) CFU, 8 of 10 volunteers experienced purging and had a positive stool culture for V. cholerae. However, at this dose, the geometric mean stool volume of 2,175 g was insufficient by study criteria. At a dose of 10(6) CFU, 14 of 15 volunteers experienced purging, with a geometric mean stool volume of 5,621 g. Disease severity was significantly greater in volunteers with blood group O than those with non-O blood types (10,353 g versus 3,555 g, P < 0.001). Following challenge, all volunteers demonstrated a significant rise in antitoxin antibodies but the serum vibriocidal titer was attenuated compared to that seen after challenge with an O1 strain. This model provides a reproducible illness of sufficient severity for testing the efficacies of new O139 or combined O1-O139 vaccines.
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Abstract
BACKGROUND Cytomegalovirus (CMV) is the most frequent known cause of congenital viral infections in humans. Cytomegalovirus is endemic throughout the world, affecting most of the population where the seroprevalence of CMV IgG is known to vary among countries. METHODS The present study was designed to show the prevalence of CMV antibodies among children aged 1 day to 15 years and women of child-bearing age in Ankara, Turkey. Antibodies to CMV were analyzed in serum samples of 318 children and 745 women using a passive particle-agglutination test. RESULTS The overall prevalence of CMV antibodies was 90.6% among children and 99% among women aged 15-49 years. The difference between stratified age groups was not statistically significant (chi 2 = 4.92, P = 0.177) in either children or females. CONCLUSIONS Our findings confirm that CMV is very prevalent in Turkey and is at the higher end of worldwide ranges. Using the results of the present study, the transmission mode of CMV infection and the risk for congenital CMV infection are discussed. We have come to the conclusion that the risk of fetal infection in Turkey cannot be predicted; however, most CMV infections in the first year of life are transmitted from mother to infant and this is the main source of infection in Turkey.
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Parker S. Nurses have an important role in consent issues. BRITISH JOURNAL OF NURSING (MARK ALLEN PUBLISHING) 1999; 8:1048. [PMID: 10711039 DOI: 10.12968/bjon.1999.8.16.6508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Autonomy is the fundamental principle underlying consent to treatment. It gives every competent adult the right to decide what may and may not be done to him/her. Any treatment, investigation or deliberate touching carried out without consent may amount to an assault or battery. This could potentially result in a legal action for damages, a criminal charge or allegations of professional misconduct.
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Zellner DA, Garriga-Trillo A, Rohm E, Centeno S, Parker S. Food liking and craving: A cross-cultural approach. Appetite 1999; 33:61-70. [PMID: 10447980 DOI: 10.1006/appe.1999.0234] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Spanish and American participants rated how much they liked three common sweets and three common beverages listed on a questionnaire. They also named the food or drink for which they had the strongest craving. Cross-cultural comparisons in liking were almost always consistent with cross-cultural comparisons in rates of exposure. In both cultures, among subjects whose cravings could be so classified more females (about 5/8) craved sweet foods than savories and more males (about 5/8) craved savories than sweets. Among sweet cravers, chocolate craving was much more frequent for American females (44.6%) than for American males (17.4%), but no such gender difference occurred for the Spaniards (28.6 and 22.2%). The results argue for a possible physiological basis for the gender differences in sweet/savory craving but against a physiological basis for chocolate craving.
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Parker S, Campbell J, Ribble C, Gajadhar A. Comparison of two sampling tools for diagnosis of Tritrichomonas foetus in bulls and clinical interpretation of culture results. J Am Vet Med Assoc 1999; 215:231-5. [PMID: 10416478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
OBJECTIVE To compare sensitivity for diagnosing Tritrichomonas foetus infection in bulls using 2 sampling tools and to calculate negative predictive values for infection. DESIGN Randomized clinical trial. ANIMALS 30 Bos taurus bulls naturally or experimentally infected with T foetus. PROCEDURE Preputial scrapings were obtained once/wk for 6 weeks using an artificial insemination pipette and a metal brush; which tool was used first for each bull was randomly determined. Samples were collected first from the left side of the prepuce and then from the right side and placed in commercially available transport media chi 2 Values and confidence limits were adjusted for effect of clustering of results by bull. RESULTS Significant differences in sensitivity of results were not found between samples collected using the brush or pipette. Using the pipette, sensitivity was estimated to be 91.6% (95% confidence interval, 84.3 to 95.7%); negative predictive values ranged from 41 to 99% for prevalence of infection of 90 to 5%, respectively. Sensitivity was 88.8% for first sample obtained and 96.1% for second sample obtained. CONCLUSIONS AND CLINICAL RELEVANCE Collection of preputial scrapings with an artificial insemination pipette or a metal brush and use of a commercially available culture system can provide a sensitive diagnostic test for T foetus infection in bulls. Calculated negative predictive values indicated that 1 or 2 tests would suffice in most clinical situations. For bulls from herds in which T foetus is endemic, 2 to 4 tests/bull may be required to ensure that each bull is not infected.
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Bazzucchi A, Hans MG, Nelson S, Powers M, Parker S. Evidence of correction of open bite malocclusion using active vertical corrector treatment. Semin Orthod 1999; 5:110-20. [PMID: 10530284 DOI: 10.1016/s1073-8746(99)80030-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
This study used a cephalometric analysis that isolated tipping and bodily tooth movements of the upper and the lower incisors and measured vertical skeletal changes in the anterior region of the maxilla and mandible to evaluate the outcome of two-phase nonextraction treatment for open bite malocclusion. Twenty-nine subjects treated with an active vertical corrector (AVC) followed by fixed 022 orthodontic appliances were selected by one orthodontist from his private practice. All subjects lacked vertical incisor contact at the start of treatment and had adequate initial, end of phase 1, and deband lateral cephalograms. Each subject in the treated group was matched by age and sex with an untreated subject from the Broadbent Bolton Collection, Cleveland, OH. Data were collected for three time intervals; phase 1 treatment with the AVC (T1 to T2), phase 2 fixed-appliance treatment (T2 to T3), and over the total treatment period (T1 to T3). Analysis of the data showed no statistically significant (P < or = .002) changes between treated subjects and controls for any variables during the phase 1 (T1 to T2) or phase 2 (T2 to T3) treatment intervals. However, overbite was significantly improved compared with controls (P < or = .002) during the T1 to T3 time interval. It was concluded that two-phase treatment with the AVC followed by fixed orthodontic appliance treatment results in a statistically significant increase in incisor overbite. The observed increase in overbite was the result of small but clinically significant changes in relative mandibular vertical growth, bodily incisor movement toward the occlusal plane, and lingual tipping of the lower incisors.
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Cook RC, Tupper JK, Parker S, Kingsbury K, Frohlich JJ, Abel JG, Gao M, Ignaszewski AP. Effect of immunosuppressive therapy, serum creatinine, and time after transplant on plasma total homocysteine in patients following heart transplantation. J Heart Lung Transplant 1999; 18:420-4. [PMID: 10363685 DOI: 10.1016/s1053-2498(99)00013-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVES To determine the prevalence of hyperhomocysteinemia in heart transplant recipients, and to assess the effect of renal function and immunosuppressive medication on total plasma homocysteine (tHcy) levels. BACKGROUND Elevated plasma tHcy levels have been associated with increased risk of mortality in patients with established coronary artery disease. Graft coronary disease is the major cause of morbidity and mortality in long-term survivors of heart transplantation. The tHcy has been found to be elevated in heart and kidney transplant patients, however, the etiologic factors have not been clearly delineated. METHODS The study group consisted of 70 heart transplant recipients (56 males, 14 females, mean age 53+/-13 years [range 17 to 69 years]). The parameters evaluated were fasting tHcy level, cumulative cyclosporine (CyA) dose, cumulative prednisone dose, serum creatinine, and time from transplantation. RESULTS The mean fasting tHcy level was 20.5+/-10.2 micromol/L (range 5.2 to 59.0 micromol/L). Sixty-one (87%) had fasting tHcy levels greater than the seventy-fifth percentile of the general population (>12.2 micromol/L in males, and >10.1 micromol/L in females). There was no difference in mean post-transplant tHcy level between patients with and without coronary artery disease before transplantation (21.0+/-11.4 vs. 19.3+/-6.7 micromol/L, p = NS). There were significant relationships between the tHcy level and the serum creatinine (r = 0.76, p<0.001), and cumulative exposure to CyA (r = 0.31, p<0.01). There were no significant relationships between tHcy levels and cumulative prednisone dose, or time from transplantation. CONCLUSIONS Fasting tHcy levels are markedly elevated in the majority of patients following heart transplantation, and are correlated to serum creatinine. Further studies are needed to determine other etiologic factors of elevated tHcy following heart transplantation, and to examine the impact of elevated tHcy on clinical outcomes.
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Parker S, Tatnell J, Austin S, Leyden M. Fluid requirements and practices of AFL football players. J Sci Med Sport 1999. [DOI: 10.1016/s1440-2440(99)80149-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Murphy E, Dingwall R, Greatbatch D, Parker S, Watson P. Qualitative research methods in health technology assessment: a review of the literature. Health Technol Assess 1999; 2:iii-ix, 1-274. [PMID: 9919458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
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212
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Parker S, Armitage M. Experience with transdermal testosterone replacement therapy for hypogonadal men. Climacteric 1999. [DOI: 10.3109/13697139909038075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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213
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Klavinskis LS, Barnfield C, Gao L, Parker S. Intranasal immunization with plasmid DNA-lipid complexes elicits mucosal immunity in the female genital and rectal tracts. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1999; 162:254-62. [PMID: 9886393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
The development of vaccines against pathogens transmitted across the genito-rectal mucosa that effectively stimulate both secretory IgA Abs and cytotoxic T lymphocytes in the genital tract and CTL in the draining lymph nodes (LN) has proven a major challenge. Here we report a novel, noninvasive approach of genetic vaccination via the intranasal route. Such vaccination elicits immune responses in the genital and rectal mucosa, draining LNs, and central lymphoid system. Intranasal immunization with plasmid DNA-lipid complexes encoding the model Ag firefly luciferase resulted in dissemination of the DNA and the encoded transcript throughout the respiratory and gastrointestinal tracts, draining LNs, and spleen. Complexing the plasmid DNA with the lipid DMRIE/DOPE enhanced expression of the encoded protein in the respiratory tract, increased specific secretory IgA Ab in the vaginal and rectal tracts, and increased the circulating levels of specific IgA and IgG. In addition, intranasal DNA immunization resulted in generation of Ag-specific CTL that were localized in the genital and cervical LNs and spleen. These results suggest that intranasal immunization with plasmid DNA-lipid complexes may represent a generic immunization strategy against pathogens transmitted across the genito-rectal and other mucosal surfaces.
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MESH Headings
- Administration, Intranasal
- Animals
- Body Fluids/enzymology
- Body Fluids/immunology
- Cytotoxicity, Immunologic
- Epithelium/enzymology
- Epithelium/immunology
- Female
- Genitalia, Female/immunology
- Immunity, Mucosal/immunology
- Immunoglobulin A, Secretory/biosynthesis
- Immunoglobulin G/biosynthesis
- Luciferases/biosynthesis
- Luciferases/genetics
- Luciferases/immunology
- Lymph Nodes/cytology
- Lymph Nodes/enzymology
- Lymph Nodes/immunology
- Mice
- Mice, Inbred BALB C
- Nasal Mucosa/enzymology
- Nasal Mucosa/immunology
- Phosphatidylethanolamines/administration & dosage
- Phosphatidylethanolamines/immunology
- Plasmids/immunology
- Plasmids/metabolism
- RNA, Messenger/metabolism
- Rectum/immunology
- Spleen/cytology
- Spleen/enzymology
- Spleen/immunology
- T-Lymphocytes, Cytotoxic/enzymology
- T-Lymphocytes, Cytotoxic/immunology
- Time Factors
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/immunology
- Vagina/enzymology
- Vagina/immunology
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Parker S. From the slums to the suburbs: Labour Party policy, the LCC, and the Woodberry Down estate, Stoke Newington, 1934-1961. THE LONDON JOURNAL 1999; 24:51-69. [PMID: 22007363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
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215
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Parker S, Martin D, Braden M. Soft acrylic resin materials containing a polymerisable plasticiser II: water absorption characteristics. Biomaterials 1999; 20:55-60. [PMID: 9916771 DOI: 10.1016/s0142-9612(98)00134-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The main disadvantage of soft acrylic resin denture lining materials is the loss of plasticiser leading to gradual hardening. One possible solution to this problem is the use of a polymerisable plasticiser. A material based on such a plasticiser failed in clinical trials due to a combination of prolonged water uptake and low strength. Similar materials with improved strength have been developed and it is the aim of this study to investigate their water uptake characteristics. Water uptake from distilled water, an artificial saliva and 0.9 M saline has been determined for three experimental materials and 'Supersoft', a commercial plasticised acrylic resin denture lining material. Solubilities were determined after 6 months and diffusion coefficients calculated where appropriate. All the experimental materials had a lower uptake and solubility than 'Supersoft' in all solutions. For each material uptake was lower from solution than from distilled water. All diffusion coefficients were in the range expected for this type of material. The water uptake of the experimental materials was influenced by the relative hydrophilicity of the monomer used.
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Abstract
BACKGROUND None of the existing options for long-term testosterone replacement therapy (TRT) for hypogonadal men are ideal. Depot replacement at frequent intervals and implants are effective but invasive and inconvenient for the patient. Oral therapy results in poor hormone levels. Both are associated with undesirable metabolic changes. A transdermal formulation therefore represents a potential therapeutic advance for testosterone replacement. OBJECTIVE To carry out a clinical audit of the acceptability and efficacy as a treatment for hypogonadism of the first transdermal testosterone therapy available in the UK (Andropatch, SmithKline Beecham) compared with existing androgen replacement options. PATIENTS AND MEASUREMENTS Serum testosterone and questionnaire data on treatment efficacy, side-effects, therapy preference, sexual dysfunction and partner's attitudes to therapy were obtained from 50 hypogonadal men prescribed long-term testosterone replacement. RESULTS Eighty per cent of the men returned analysable questionnaires. Eighty-four per cent experienced adverse effects with transdermal therapy, most commonly dermatological problems; 22% of the sample elected to continue with transdermal therapy, 72% returned to depot and 5% returned to oral therapy. The reservoir patches were judged to be too large, uncomfortable, visually obtrusive and noisy. Testosterone levels were comparable to those obtained with depot replacement with the added advantage of a more physiological pharmacokinetic profile. Men taking oral preparations were consistently under-replaced. CONCLUSIONS Adverse events were substantially higher than reported from clinical trials but in keeping with the spectrum of yellow card reports received by the Committee on Safety of Medicines. The pharmacokinetic advantages are thus largely outweighed by low patient acceptability. In its present form transdermal therapy remains an expensive option for those who cannot tolerate depot testosterone replacement.
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Kashio N, Matsumoto W, Parker S, Rothstein DM. The second domain of the CD45 protein tyrosine phosphatase is critical for interleukin-2 secretion and substrate recruitment of TCR-zeta in vivo. J Biol Chem 1998; 273:33856-63. [PMID: 9837977 DOI: 10.1074/jbc.273.50.33856] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The CD45 protein tyrosine phosphatase (PTPase) has been shown to regulate the activity of Lck and Fyn protein tyrosine kinases in T cells. However, it is not clear that these constitute the only CD45 substrates. Moreover, the manner by which PTPase activity and substrate recruitment are regulated, is poorly understood. Previous in vitro studies suggest that the first cytoplasmic PTPase domain (D1) of CD45 is the active PTPase, which may be regulated by an enzymatically inactive second PTPase domain (D2). However, the function of CD45 D2 in vivo is unknown. In this study, reconstitution of CD45(-) T cells with specific CD45 PTPase mutants allowed demonstration of a critical role for D2 in TCR-mediated interleukin (IL)-2 production. Specifically, replacement of CD45 D2 with that of the LAR PTPase to form a CD45/LAR:D2 chimera, abrogates CD45-dependent IL-2 production. This effect cannot be accounted for by loss of PTPase activity per se. The expression of D1 substrate-trapping mutants reveals an in vivo interaction between CD45 and TCR-zeta that is dependent on CD45 D2. Thus, cells expressing CD45 lacking D2 exhibit abnormal TCR-mediated signaling characterized by hyperphosphorylation of zeta and deficient ZAP-70 phosphorylation. These data suggest an essential role for CD45 D2 in TCR-regulated IL-2 production through substrate recruitment of the zeta chain.
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Crews J, Ehlen KJ, Goodwin P, Guy A, Morrison G, Parker S, Peddie E. Yes. No. Maybe. That's about as firm as the guidance gets over launching a provider-sponsored health plan. Strategy roundtable. HOSPITALS & HEALTH NETWORKS 1998; 72:42, 44, 46-8. [PMID: 9871417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Few participants in our roundtable on provider-sponsored health plans see them the same way. Some are gearing up new products, others are scaling back or getting out. Yet they agreed on one thing: The financial risks are tremendous.
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McLearn KT, Zuckerman BS, Parker S, Yellowitz M, Kaplan-Sanoff M. Child development and pediatrics for the 21st century: the healthy steps approach. J Urban Health 1998; 75:704-23. [PMID: 9854235 PMCID: PMC3456019 DOI: 10.1007/bf02344501] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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220
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Parker S. Lasers in dentistry. BRITISH DENTAL NURSES' JOURNAL (FLEETWOOD, ENGLAND : 1994) 1998; 57:7-9. [PMID: 9790010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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221
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Parker S, Martin D, Braden M. Soft acrylic resin materials containing a polymerisable plasticiser I: mechanical properties. Biomaterials 1998; 19:1695-701. [PMID: 9840005 DOI: 10.1016/s0142-9612(98)00077-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Conventional soft acrylic resin materials depend on the use of plasticisers for their compliance. In aqueous environments the plasticisers leach out causing the material to harden. Use of a polymerisable plasticiser has been shown to solve this problem. One such material was developed but failed mechanically during clinical trial. The aim of this study was to reformulate to produce a material with improved strength. Three different methacrylate monomers were used with two different levels of plasticiser, each monomer mix was used with the same copolymer powder at three powder/liquid ratios. Tensile strength, tear energy and hardness were measured and results compared with 'Supersoft', a proprietary plasticised acrylic resin soft lining material. All the experimental materials had a higher tensile strength than the original Parker/Braden material. The 30% plasticiser materials with the higher powder/liquid level had strength, tear energy and hardness values in the same range as 'Supersoft'. Materials of improved strength have been produced.
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Dingwall R, Murphy E, Watson P, Greatbatch D, Parker S. Catching goldfish: quality in qualitative research. J Health Serv Res Policy 1998; 3:167-72. [PMID: 10185376 DOI: 10.1177/135581969800300308] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This paper reviews the contribution of qualitative methods to health services research (HSR) and discusses some of the issues involved in recognizing quality in such work. The place of qualitative work is first defined by reference to Archie Cochrane's agenda for HSR and the limitations of the recent focus on randomized trials as the standard method. Health care practice involves large elements of improvisation which cannot be captured by evidence-based approaches. Qualitative methods offer ways of understanding this improvisation and of identifying more efficient and effective practices, as well as considering the traditional topics of equity and humanity. The methodological procedures of qualitative work reflect a long-established inductive tradition in scientific practice. The logic of grounded theory provides a contemporary specification. In its application, it is quite different from the methodological anarchy of postmodernism. The use of qualitative research and the theoretically stated generalizations which arise from it inform reflective work by health service managers, planners and clinicians.
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Parker S. Lasers in dentistry. BRITISH DENTAL NURSES' JOURNAL (FLEETWOOD, ENGLAND : 1994) 1998; 56:14-6 contd. [PMID: 9564081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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225
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Wright PS, Young KA, Riggs PD, Parker S, Kalachandra S. Evaluating the effect of soft lining materials on the growth of yeast. J Prosthet Dent 1998; 79:404-9. [PMID: 9576314 DOI: 10.1016/s0022-3913(98)70153-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
STATEMENT OF PROBLEM Soft lining materials continue to have a place in clinical removable prosthodontics. However, there is an increased probability of yeast colonization on soft lining materials. PURPOSE This study (1) assessed a method of evaluating the effect of long-term soft lining materials on the growth of yeast and (2) investigated the effect five soft lining materials had on the growth of three species of yeast. MATERIAL AND METHODS Coe Supersoft, Novus, and three experimental soft lining materials were investigated together with Candida albicans, Candida tropicalis, and Issatchenkia orientalis (formerly Candida krusei) yeasts. Strips of soft lining material incubated on blood agar plates were examined for inhibition of the growth of yeast. Soft lining materials soaked in sterile trypticase soya broth or water were inoculated with yeast and incubated. The change in colony forming units per milliliter from the initial load of yeast at 3 days was measured. Statistical analysis was performed with an independent paired Student t test. RESULTS Inhibition of yeast growth occurred for two soft lining materials. Despite the presence of sufficient viable organisms, differences between the initial load of yeast and the 3-day results were mostly small, both for the test and control groups, suggesting that the material does not support the growth of the tested yeast during this period. CONCLUSIONS The often described increased prevalence of yeast associated with soft lining materials in the oral environment is likely related to readily available nutrients in the mouth and the difficulty in maintaining and cleaning these materials.
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