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51.
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   
52.
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   
53.
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   
54.
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   
55.
56.
Between 1953 and 1989 eighty cases of non-traumatic brain abscess were treated in our department. We have re-examined the clinical and neuroradiological features of this pathological process and present our therapeutic approach and results. We believe that the optimal treatment for brain abscess consists of surgical removal.The prognosis for these lesions has undergone a marked improvement over the last two decades in response to neuroradiological, microbiological and surgical advances. The most influential prognostic factor seems to be preoperative clinical status.  相似文献   
57.
This article describes the acute and long-term clinical outcomes of 310 consecutive patients who underwent directional coronary atherectomy (DCA) for treatment of coronary artery disease. An overall procedural success rate of 95% was noted with a total major complication rate of 5%. Analyses of minimal luminal diameter (MLD) were performed pre- and post-procedure for 160 patients. Clinical follow-up including treadmill testing and/or clinical symptoms was obtained on 293 patients. Results of angiographic analyses corresponded with the Kuntz model suggesting that larger MLDs are associated with lower restenosis rates. The overall target vessel revascularization rate was 27.6%, with a mean post-procedure percent diameter stenosis of 16%. These results indicate that DCA is associated with acceptable clinical restenosis rates, complications and long-term outcome.  相似文献   
58.
Summary We report a case of association of a brain tumor with multiple colorectal polyposis and offer an analysis of the relevant literature with a view to revising the classification of the syndrome in relation to familial multiple polyposis and Gardner's syndrome. Differences emerged, depending on the brain tumor type, which suggests that this association may be classified as two distinct syndromes.  相似文献   
59.
In this study, the prevalence of Toxocara spp. was evaluated in the soil of 22 public playgrounds of Ancona (Italy). The public playgrounds were selected according to the different areal distribution (centre, low-lying areas centre, hilly areas suburbs) within the urban area of Ancona, central Italy. In six playgrounds there were signs restricting access for dogs; all of them were frequented by children. Parasites were found in the soil samples from 21 out of 22 playgrounds (95.5%). The most prevalent helminth found was Toxocara canis, the common roundworm of dogs. It was detected in the soil samples from 12 (54.5%) playgrounds. This study showed a low frequency of the other parasites. Our data highlight the need for improved knowledge of the relationship between humans and stray animals. Indeed several zooparasites have a role in the etiopathogenesis of common human diseases. The high environmental contamination frequency found underlines the necessity of prompt preventive public health measures, such as control of stray animals, treatment of infected pets and hygiene education of the population to increase awareness of potential zoonotic hazards.  相似文献   
60.
Spinal neurinomas and meningiomas in children   总被引:3,自引:0,他引:3  
Summary The literature on spinal neurinomas (N) and meningiomas (M) in children is reviewed, and five personal cases of N are added (one in the context of Recklinghausen's disease). The cases of N totalled 151, and of M 69, accounting respectively for 10.9% and 4.3% of childhood spinal tumours and 2.6% and 1.3% of spinal N and M of all ages. Sixty-one cases of N (16 in the context of Recklinghausen's disease) and 26 cases of M (5 in the context of Recklinghausen's disease) are analyzed in detail. N occurs chiefly between ages 9 and 15 years, the sex ratio is 3 2, all levels of the spinal canal are equally affected, and extradural N or conditions with an extradural component (48%) are more frequent than in adults (26.9%). M occurs chiefly between 12 and 15 years, the sex ratio is 3 2, the prevalence of the thoracic segment (47.8%) is less marked than in adults (81%), and the frequency of the extradural site (10.6%) is close to the sum of the extradural and dumb-bell lesions in adults (11.1%). In children vertebral signs,i.e., spinal rigidity and tenderness, and spasm of paravertebral muscles, are more intense, earlier, and more frequent than in adults, and the clinical history is shorter. The chances of recovery from neurological deficits are greater, as are those of malignant degeneration.  相似文献   
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