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41.
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
42.
43.
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
44.
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
45.
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
46.
Bode C Kohler B Moser M Schmittner M Smalling RW Strasser RH 《Expert opinion on investigational drugs》1997,6(8):1099-1104
Reteplase (r-PA) is a genetically engineered deletion mutant of wild-type tissue-type plasminogen activator. The structural differences lead to different functional properties, such as a prolonged half-life. The compound demonstrated good thrombolytic efficacy in in vitro as well as in animal studies. In angiographically controlled patency studies (GRECO, GRECO-2 RAPID-1, RAPID-2), the double-bolus application scheme was established, and a superior patency profile for reteplase in comparison to alteplase was demonstrated. Mortality studies established reteplase as a safe drug with a 30-day mortality at least equivalent to streptokinase (INJECT) and very similar to alteplase (GUSTO-3). A possible advantage may be the double-bolus application without a need for weight adjustment, especially in a prehospital setting. Thus, reteplase can be regarded as an excellent alternative to streptokinase or alteplase for thrombolytic therapy in acute myocardial infarction. 相似文献
47.
Presence of antibodies reacting with porcine circovirus in sera of humans,mice, and cattle 总被引:20,自引:0,他引:20
I. Tischer L. Bode J. Apodaca H. Timm D. Peters R. Rasch S. Pociuli E. Gerike 《Archives of virology》1995,140(8):1427-1439
Summary Antibodies reacting with porcine circovirus (PCV) were found in sera of humans, mice, and cattle by means of an indirect immunofluorescence assay (IFA) and an ELISA. In man, the highest seroprevalence (23.9% in IFA and 30.2% in ELISA) was found among hospitalized patients with fever of partially unclear etiology. Non-hospitalized healthy persons of the former German Democratic Republic showed a significantly higher number of positive sera (IFA=20%) than blood donors from Berlin-West (IFA=8.6%). Murine sera reacted positive with PCV in IFA between 12 to 69% in different breeding groups and about 35% of cattle sera were found reactive with PCV in IFA. Double-staining IFAs, immuno-electron microscopy and immunoblotting showed that non-porcine antibodies reacted with PCV structural antigen. Mathematical analysis releaved that in ELISA, non-porcine antibodies reacted specifically with PCV. Loss of binding specificity of non-porcine antibodies in ELISA after storage of sera and lower maximal optical densities obtained at equal titers in ELISA with non-porcine than with porcine sera suggest that antibodies in man, mice and cattle are caused by related species specific viruses sharing antigenic epitopes with PCV. 相似文献
48.
49.
Chen D Apple DF Hudson LM Bode R 《Archives of physical medicine and rehabilitation》1999,80(11):1397-1401
OBJECTIVES: To examine the frequency of common secondary medical complications during acute rehabilitation in persons with new spinal cord injury (SCI). DESIGN: Survey and analysis of data in the National SCI Statistical Center (NSCISC) database. SETTING: Eighteen Model System SCI Centers located in urban, public medical centers around the United States. SUBJECTS: A total of 1,649 persons with new SCI entered into the NSCISC database between 1996 and mid-1998. RESULTS: Since 1992, the number of days from injury to admission to rehabilitation has steadily decreased, resulting in the increased potential to develop common secondary medical complications during rehabilitation hospitalization. Pressure ulcers occur with high frequency and were found to have developed in 23.7% of patients during rehabilitation. In addition, autonomic dysreflexia and atelectasis/pneumonia also occur with relative frequency during rehabilitation. Conversely, deep vein thrombosis and pulmonary embolism have decreased, most likely because of greater awareness of their potential to develop, as well as improved methods of prophylaxis. Cardiopulmonary arrest and gastrointestinal hemorrhage occur with relatively small frequency. The frequency of renal complications is difficult to gauge because of the decreasing number of patients who have any renal testing performed during rehabilitation hospitalization. CONCLUSION: The continued declining lengths of acute care hospitalization after SCI have resulted in the occurrence in the rehabilitation setting of medical complications that were previously seen in acute care. Greater awareness and attention to these conditions are necessary to reduce their occurrence, so that obstacles to recovery and functional improvement after SCI are minimized. 相似文献
50.
In acute myocardial infarction rapid, complete, and sustained reperfusion of the infarct-related coronary artery is the most important therapeutic principle. Lanoteplase or n-PA, a third-generation plasminogen activator consisting of a deletion and point mutant of tissue-type plasminogen activator (t-PA), is a promising agent to approach this therapeutic goal. The molecule exhibits an increased plasma half-life allowing single-bolus administration. In this article, after characterizing the n-PA molecule, the currently available pharmacokinetic and pharmacodynamic data including the results of the InTIME study are reviewed. 相似文献