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81.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
82.
Canfield MC; Tamarappoo BK; Moses AM; Verkman AS; Holtzman EJ 《Human molecular genetics》1997,6(11):1865-1871
Congenital nephrogenic diabetes insipidus (NDI) is a rare disease caused
most often by mutations in the vasopressin V2 receptor (AVPR2). We studied
a family which included a female patient with NDI with symptoms dating from
infancy. The patient responded to large doses of desmopressin (dDAVP) which
decreased urine volume from 10 to 4 I/day. Neither the parents nor the
three sisters were polyuric. The patient was found to be a compound
heterozygote for two novel recessive point mutations in the aquaporin-2
(AQP2) gene: L22V in exon 1 and C181W in exon 3. Residue Cys181 in AQP2 is
the site for inhibition of water permeation by mercurial compounds and is
located near to the NPA motif conserved in all aquaporins. Osmotic water
permeability (Pf) in Xenopus oocytes injected with cRNA encoding C181W-AQP2
was not increased over water control, while expression of L22V cRNA
increased the Pf to approximately 60% of that for wild-type AQP2.
Co-injection of the mutant cRNAs with the wild-type cRNA did not affect the
function of the wild-type AQP2. Immunolocalization of AQP2-transfected CHO
cells showed that the C181W mutant had an endoplasmic reticulum-like
intracellular distribution, whereas L22V and wild-type AQP2 showed endosome
and plasma membrane staining. Water permeability assays showed a high Pf in
cells expressing wild-type and L22V AQP2. This study indicates that AQP2
mutations can confer partially responsive NDI.
相似文献
83.
Debelenko LV; Brambilla E; Agarwal SK; Swalwell JI; Kester MB; Lubensky IA; Zhuang Z; Guru SC; Manickam P; Olufemi SE; Chandrasekharappa SC; Crabtree JS; Kim YS; Heppner C; Burns AL; Spiegel AM; Marx SJ; Liotta LA; Collins FS; Travis WD; Emmert-Buck MR 《Human molecular genetics》1997,6(13):2285-2290
Lung carcinoids occur sporadically and rarely in association with multiple
endocrine neoplasia type 1 (MEN1). There are no well defined genetic
abnormalities known to occur in these tumors. We studied 11 sporadic lung
carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene
on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy
fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was
studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene
were inactivated. All four tumors showed the presence of a MEN1 gene
mutation and loss of the other allele. Observed mutations included a 1 bp
insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide
substitution affecting a donor splice site. Each mutation predicts
truncation or potentially complete loss of menin. The remaining seven
tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH.
The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a
complex germline MEN1 gene mutation. The data implicate the MEN1 gene in
the pathogenesis of sporadic lung carcinoids, representing the first
defined genetic alteration in these tumors.
相似文献
84.
Maša Davidović Nadine Zielonke Iris Lansdorp-Vogelaar Nereo Segnan Harry J. de Koning Eveline AM. Heijnsdijk 《Value in health》2021,24(3):353-360
ObjectivesTo quantify the impact of mammography-based screening on the quality of life, disability-adjusted life years (DALYs) averted or quality-adjusted life years (QALYs) gained can be used. We aimed to assess whether the use of DALYs averted or QALYs gained will lead to different cost-effective screening strategies.MethodsUsing the microsimulation model MISCAN, we simulated different breast cancer screening strategies varying in starting age (starting at 45, 47, and 50 years), stopping age (stopping at 69, 72, and 74 years), and frequency (annual [A], biennial [B], combination of both [A + B], and triennial [T]). In total, we defined 24 different breast cancer screening strategies, including no screening as a reference strategy. We calculated incremental cost-effectiveness ratios (ICERs) and compared which strategies were on the efficiency frontiers for DALYs and QALYs.ResultsBreast cancer screening averted between 46.00 and 105.58 DALYs and gained between 28.69 and 64.50 QALYs per 1000 women. For DALYs there were 5 strategies on the efficiency frontier (T50-69, T50-74, T45-74, B45-74, and A45-74). The same strategies plus one (B45-72) were on the efficiency frontier for QALYs.ConclusionsUsing DALYs averted instead of QALYs gained to assess the effects on quality of life from breast cancer screening in the Dutch population yields differences in ICERs, but almost the same strategies were on the efficiency frontiers. Whether the choice in outcome measure leads to a difference in optimal policy depends on the cost-effectiveness threshold. 相似文献
85.
Seroprevalence of and risk factors for HIV-1 infection in injection drug users in Montreal and Toronto: a collaborative study. 总被引:1,自引:1,他引:0
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F Lamothe J Bruneau R Coates J G Rankin J Soto R Arshinoff M Brabant J Vincelette M Fauvel 《Canadian Medical Association journal》1993,149(7):945-951
OBJECTIVE: To determine the prevalence of antibodies to HIV-1 and risk factors for HIV-1 infection among injection drug users. DESIGN: Questionnaire survey. A venous blood sample was taken for HIV-1 antibody testing. SETTING: Montreal and Toronto. PARTICIPANTS: A total of 810 subjects who had used injection drugs in the previous 6 months recruited mainly from treatment centres and from the street in Montreal (425 subjects) and from treatment centres in Toronto (385 subjects) between September 1988 and September 1990. The overall participation rate was 82%. OUTCOME MEASURES: HIV-1 seropositivity, sociodemographic and behavioural risk factors for HIV-1 infection. RESULTS: The overall seroprevalence rate of HIV-1 infection was 4.8% (95% confidence limits [CL] 3.5 and 6.5). In Montreal the rate was 8.2% (95% CL 6.0 and 11.2), and in Toronto 1.0% (95% CL 0.4 and 2.6) (p < 0.001). Seropositive subjects were significantly older (p = 0.041) and were more likely to have a history of imprisonment (p = 0.006) than seronegative subjects. In univariate analysis seropositivity was associated with the following behaviours: more frequent cocaine use (p < 0.001), injecting drugs in "shooting galleries" (p = 0.002), sharing equipment with a person known to be HIV-1 seropositive (p = 0.006), "booting" fresh blood (p = 0.004), homosexual or bisexual orientation (p = 0.006), engaging in prostitution (p < 0.001) and, for men, number of male sexual partners in the previous 6 months (p = 0.007). In multivariate analysis the determinants of HIV-1 seropositivity were Montreal as the city of recruitment (odds ratio [OR] 6.7, 95% CL 2.32 and 19.42), engaging in prostitution (OR 2.13, 95% CL 1.01 and 4.75), a history of imprisonment (OR 3.51, 95% CL 1.33 and 9.29) and sharing equipment with a person known to be HIV-1 seropositive (OR 4.43, 95% CL 1.43 and 13.74). CONCLUSIONS: Our findings show that HIV-1 is circulating among injection drug users in Montreal and Toronto and that both drug use and sexual behaviours are implicated in the transmission of infection in the populations studied. Adapted preventive programs should be developed to prevent further spread of HIV-1 infection in this population. 相似文献
86.
Dentists, while recognising the need to be more marketing orientated, still have some way to go to improve the perception of themselves and their services in the eyes of the public. Nigel Coates and John Willans suggest some ways to address the barriers to visiting dentists. 相似文献
87.
A. Goldhirsch R. D. Gelber M. Castiglione A. O'Neill B. Thürlimann C.-M. Rudenstam J. Lindtner J. Collins J. Forbes D. Crivellari A. Coates F. Cavalli E. Simoncini M. F. Fey O. Pagani K. Price H.-J. Senn 《Annals of oncology》1997,8(8):751-756
Purpose: It has been postulated that breast cancer surgery performedduring the follicular phase of the menstrual cycle is associated with pooreroutcome.Patients and methods: We tested this hypothesis by evaluatingdisease-free survival (DFS) for 1033 premenopausal patients who receiveddefinitive surgery either during the follicular phase (n = 358) or theluteal phase (n = 675). All patients were enrolled in a randomized trialconducted between July 1986 and April 1993. All had node positive breastcancer and randomization was stratified by estrogen receptor (ER) status.All patients received at least three cycles of adjuvant cyclophosphamide,methotrexate, and 5-fluorouracil (CMF). The median follow-up was 60 months.Results: Patients who underwent definitive surgery for breast cancer inthe follicular phase had a slightly worse disease-free survival than thoseoperated on during the luteal phase (five-year DFS percentage: 53%versus 58%; hazard ratio, 1.13; 95% confidence interval (CI),0.94–1.38; P = 0.20). The effect was significantly greater for thesubpopulation of 300 patients with ER-negative primaries (P = 0.02interaction effect; five-year DFS percentages 42% vs. 59%;hazard ratio 1.60; 95% CI, 1.12–2.25; P = 0.008). The effect oftiming of surgery diminished for analyses based on lesser surgicalprocedures, e.g., excisional biopsies. In particular, no effect of timingwas observed for fine needle aspiration procedures.Conclusions: Surgical procedures which are more extensive than a fineneedle aspiration biopsy might be associated with worse prognosis if conductedduring the follicular phase of the menstrual cycle. This phenomenon was seenpredominantly for high risk breast cancer with low levels or no estrogenreceptors in the primary tumor. 相似文献
88.
Plant foods and colon cancer: an assessment of specific foods and their related nutrients (United States) 总被引:3,自引:0,他引:3
Martha L. Slattery John D. Potter Ashley Coates Khe-Ni Ma T. Dennis Berry Debra M. Duncan Bette J. Caan 《Cancer causes & control : CCC》1997,8(5):575-590
Plant foods have been associated inversely with colon cancer. Since amajor focus of this study was to identify components of plant foods whichmay account for their association with colon cancer, nutrients which arecommonly found in plant foods also were evaluated. A population-basedcase-control study was conducted in Northern California, Utah, and the TwinCities area of Minnesota (United States). Complete data were available frominterviewer-administered questionnaires on 1,993 cases and 2,410 controls.Higher intakes of vegetables (for highest relative to lowest quintile ofintake) were associated inversely with colon cancer risk: the odds ratio(OR) was 0.7 for both men (95 percent [CI] confidence interval = 0.5-0.9)and women (CI = 0.5-1.0). Associations were stronger among those withproximal tumors. Total fruit intake was not associated with colon cancerrisk although, among men, higher levels of whole grain intake wereassociated with a decreased risk (OR = 0.6, CI = 0.4-0.9 for older men);high intakes of refined grains were associated with an increased risk (OR =1.5, CI = 1.1-2.1). Dietary fiber intake was associated with a decreasedrisk of colon cancer: OR = 0.5 (CI = 0.3-0.9) for older men; OR = 0.7 (CI =0.4-1.2) for older women; OR = 0.6 (CI = 0.4-1.0) for men with proximaltumors; OR = 0.5 (CI = 0.3-0.9) for women with proximal tumors. Othernutrients, for which plant foods were the major contributor - such asvitamin B6, thiamin, and niacin (women only) - also were associatedinversely with colon cancer. Neither beta-carotene nor vitamin C wasprotective for colon cancer. Adjustment of plant foods for nutrients foundin plant foods or for supplement use did not appreciably alter the observedassociations between plant foods and colon cancer. 相似文献
89.
Drs Margaret McCredie Marylon Coates Andrew Grulich 《Cancer causes & control : CCC》1994,5(5):414-421
The incidence of cancer in migrants to New South Wales (NSW) from Cyprus, Egypt, Iran, Iraq, Israel, Lebanon, Syria, and Turkey has been compared with that in the Australian-born population using data from the NSW Central Cancer Registry for 1972–91. Age-standardized incidence rates showed overall cancer incidence to be less common in migrants from each Middle Eastern country than in the Australian-born. There was a clear pattern of generally low rates for cancers of the mouth and pharynx, esophagus, colon and rectum, lung (men only), ovary, prostate and testis, and melanoma. Cancers which tended to be more common in migrants were nasopharynx, stomach (women only), liver (men only), gallbladder (chiefly in women), bladder (men only), and thyroid. Breast cancer did not show a uniform pattern among migrant groups, rates being high in the Egyptian-born but low in Lebanese-born women. The overall low incidence of cancers related to tobacco and alcohol, and to a high fat, low fiber diet, emphasizes the potential role of preventable lifestyle factors in the burden of cancer in Australia. 相似文献
90.
R J Coates D J Bowen A R Kristal Z Feng A Oberman W D Hall V George C E Lewis M Kestin M Davis M Evans J E Grizzle C K Clifford 《American journal of epidemiology》1999,149(12):1104-1112
This randomized clinical trial examined the feasibility of low-fat dietary interventions among postmenopausal women of diverse backgrounds. During 1992-1994, 2,208 women aged 50-79 years, 28% of whom were black and 16% Hispanic, enrolled at clinics in Atlanta, Georgia, Birmingham, Alabama, and Miami, Florida. Intervention/support groups met periodically with a nutritionist to reduce fat intake to 20% of energy and to make other diet modifications. At 6 months postrandomization, the intervention group reduced fat intake from 39.7% of energy at baseline to 26.4%, a reduction of 13.3% of energy, compared with 2.3% among controls. Saturated fatty acid and cholesterol intakes were reduced, but intakes of fruits and vegetables, but not grain products, increased. Similar effects were observed at 12 and 18 months. Black and non-Hispanic white women had similar levels of reduction in fat, but the decrease in Hispanic women was less. Changes did not vary significantly by education. While bias in self-reported intakes may have resulted in somewhat overestimated changes in fat intake, the reported reduction was similar to the approximately 10% of energy decrease found in most trials and suggests that large changes in fat consumption can be attained in diverse study populations and in many subgroups. 相似文献