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71.
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
72.
Lipocalin-type prostaglandin D synthase (L-PGDS) is dominantly expressed in the leptomeninges surrounding the brain and secreted into the cerebrospinal fluid as β-trace, a major cerebrospinal fluid protein. To examine the interaction between the leptomeninges and the brain parenchyma, we co-cultured rat leptomeningeal cells with cells dissociated from the neonatal rat cortex and found that the production of L-PGDS was remarkably increased after the co-cultivation. A similar increase in L-PGDS production was observed by the co-culturing of the leptomeningeal cells with cells dissociated from astrocyte-rich cultures or with 1321-N1 astrocytoma cells. When a crude membrane fraction prepared from 1321-N1 cells was added to leptomeningeal cell cultures, L-PGDS gene expression was slowly increased up to 48 h after the addition. These results indicate that leptomeningeal cells enhance their L-PGDS production by a slow activation of L-PGDS gene expression through their contact with astrocytes. 相似文献
73.
Ko JM Yau WL Chan PL Lung HL Yang L Lo PH Tang JC Srivastava G Stanbridge EJ Lung ML 《Genes, chromosomes & cancer》2005,43(3):284-293
Despite the abundant evidence of high allelic loss of chromosome arm 14q in human cancers, tumor-suppressor genes mapped to this chromosome have yet to be identified. To narrow the search for candidate genes, we performed monochromosome transfer of chromosome 14 into an esophageal carcinoma cell line, SLMT-1 S1. Statistically significant suppression of the tumorigenic potential of microcell hybrids containing the transferred chromosome 14 provided functional evidence that tumor-suppressive regions of chromosome 14 are essential for esophageal cancer. Tumor segregants emerging in nude mice during the tumorigenicity assay were analyzed by detailed PCR-microsatellite typing to identify critical nonrandomly eliminated regions (CRs). A 680-kb CR mapped to 14q32.13 and an approximately 2.2-Mb CR mapped to 14q32.33 were delineated. Dual-color BAC FISH analysis of microcell hybrids and tumor segregants verified the selective loss of the 14q32.13 region. In contrast, similar transfers of an intact chromosome 11 into SLMT-1 S1 did not significantly suppress tumor formation. These functional complementation studies showing the correlation of tumorigenic potential with critical regions of chromosome 14 validated the importance of the 14q32 region in tumor suppression in esophageal cancer. The present study also paved the path for further identification of novel tumor-suppressor genes that are relevant to the molecular pathogenesis of esophageal cancer. 相似文献
74.
Toshiaki Maruyama Ichiro Saito Sachiko Miyake Hiroshi Hashimoto Kazuto Sato Hideo Yagita Ko Okumura Nobuyuki Miyasaka 《European journal of immunology》1993,23(9):2059-2065
Synovial T cells play a crucial role in the pathogenesis of rheumatoid arthritis (RA) synovitis. We have quantitatively analyzed the T cell receptor (TcR) variable (V) region gene repertoire of freshly isolated synovial fluid (SF) T cells, comparing it with that of peripheral blood (PB) T cells in RA. The TcR V gene repertoire of PB and SF T cells in RA and osteoarthritis was heterogeneous. In contrast, Vail in SF was expressed to a greater degree in three of five RA patients, and increased levels of Vp6, 1-3 were found in the SF of four of six RA, compared with paired PB. Of note, Vβ6, 1–3 was universally used in four RA patients with a disease duration of less than 10 years, irrespective of their HLA-DR types. This was in contrast to two other RA patients, suffering for more than 20 years, who showed different Vα and Vβ usages. β-chain sequence analysis in RA patients with a preference for Vβ6, 1–3 has shown that a few clones dominated in SF, whereas polyclonality was observed in PB. These findings suggest oligoclonal expansion of T cells in response to specific antigen(s) in the SF of these patients with RA of relatively short duration. Concomitant use of two hydrophobic amino acids, leucine and valine, in the Dβ region was noticeable among the predominant SF clones. These two amino acids might directly contact a peptide specific for the induction of synovitis in RA patients. TcR-directed therapy may, therefore, be useful for the treatment of early RA synovitis. 相似文献
75.
The polyhedrin gene inBombyx morinucleopolyhedrovirus (BmNPV) was replaced with the granulin gene ofTrichoplusia nigranulovirus (TnGV). The substitution was verified by Southern hybridization, and expression of granulin by the mutant virus, BmGran, was demonstrated by sodium dodecyl sulfate–polyacrylamide gel electrophoresis and by amino acid sequencing of the predominant protein of BmGran inclusion bodies (IBs). Light and electron microscopy examination of BmGran-infectedB. moriand BmN cells revealed large, cuboidal, polyhedron-like IBs in the nucleus and cytoplasm, but granules were not seen. IBs contained small, parallel, electron-dense streaks, which defined the geometric pattern of crystallization. Geometric patterns of nuclear IBs were frequently disrupted by occlusion of polyhedron envelope fragments, resulting in IB instability and fracturing. Virions were not embedded in most of the polyhedron-like IBs, but accumulated with polyhedron envelope fragments. Some virions were coated with matrix protein and were partially wrapped by polyhedron envelope. These results suggested that (1) the amino acid sequence of granulin is insufficient for determining IB morphology in TnGV-infected cells, and TnGV may have genes, not present in BmNPV, that control granule formation, and (2) interactions among the virion, the IB envelope, and the matrix protein may be important in virion occlusion and IB morphology and stability. 相似文献
76.
C. R. Kumana I. J. Lauder M. Chan W. Ko H. J. Lin 《European journal of clinical pharmacology》1987,32(2):211-215
Summary We have compared diazepam pharmacokinetics in 16 Chinese and 18 white Caucasian healthy male volunteers, resident in Hong Kong and have correlated them with physical attributes. Serum concentrations of diazepam and desmethyldiazepam were measured in venous blood by an enzyme-linked immunoassay (0–3 h samples) and HPLC (3–72 h samples). Pharmacokinetic parameters were derived assuming a two compartment model, distribution phase <6 h, and 100% oral systemic availability. Compared with the Chinese the white Caucasians were older, heavier, taller, and fatter, as judged by skin fold thickness (SFT) and total body weight to Ideal body weight (TBW/IBW) ratio; respective mean differences being 16%, 27%, 4%, 26%, and 15% (p<0.05). Mean diazepam apparent volume of distribution (V) and V/IBW were larger in the white Caucasians (52% & 39% respectively, p=0.002). SFT and TBW/IBW ratio yielded the best correlations with V, V/TBW and V/IBW (0.50–0.75, p<0.05). Obesity indices contributed most to the overall regressions (R2 up to 0.52), and for V there was a further small effect (2%, partial F test) due to ethnic group, possibly reflecting stature. Mean peak diazepam concentration (Cmax) was similar in both ethnic groups. Time to Cmax (tmax) was more often prolonged in the Chinese (X
2 test, p=0.01). Body fat and stature may thus account for these inter-ethnic differences in the apparent volume of distribution of diazepam, a highly lipid-soluble drug. 相似文献
77.
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
78.
79.
Keun Ho Park Dong Hwi Kim Se Woong Jang Je Hong Ryu Kang Yeol Ko 《Clinics in Orthopedic Surgery》2021,13(2):152
BackgroudRecurrent hemarthrosis following total knee arthroplasty (TKA) is a rare complication. Its pathophysiology and standard treatments have not yet been established. In this study, we report 7 cases of recurrent hemarthrosis after TKA in which failure of the initial conservative treatment was followed by angiographic embolization; in 1 of the 7 cases, arthroscopic electrocauterization was also performed after treatment failure with selective embolization.MethodsFrom January 2015 to May 2018, 7 patients visited our hospital due to recurrent hemarthrosis after TKA. Their medical records and serologic test results were reviewed to check for the presence of any bleeding disorder and history of anticoagulant use. Implant malalignment and instability were checked using X-ray. In all cases, the conservative treatment failed, so interventional angiography with selective embolization was performed, which was also followed by arthroscopic electrocauterization if the outcome was unsatisfactory.ResultsThe interval between TKA and the onset of hemarthrosis ranged from 3 to 76 months (average, 34.1 months). There was no coagulopathy and instability. All patients underwent conservative treatment at an interval of 4.3 months and the rate of relapse was 3.1 on average. On the interventional angiography, 6 cases showed vascular blush, and 1 case had pulsatile bleeding. The average duration for interventional angiography was 90.9 minutes. The average length of follow-up was 38.8 months. Embolization was successfully performed in 4 cases. In 2 of 3 failed cases, the symptoms improved without further treatment. In the remaining 1 failed case, the patient had a relapse of hemarthrosis, so an arthroscopic procedure was performed, which led to identification of the suspicious bleeding point by using preoperative angiographic findings. Electrocauterization was performed and active bleeding was stopped. All cases with recurrent hemarthrosis achieved improvement.ConclusionsInterventional angiography was used to aid in the diagnosis of recurrent hemarthrosis, and therapeutic selective embolization provided satisfactory clinical results. Even if selective embolization fails, interventional angiography may be helpful for further surgical procedures because it reveals vascular blush of a bleeding site. Therefore, interventional angiography and selective embolization should be considered to be a useful treatment for recurrent hemarthrosis after TKA. 相似文献
80.
Wen MC Wei CH Hu ZQ Srivastava K Ko J Xi ST Mu DZ Du JB Li GH Wallenstein S Sampson H Kattan M Li XM 《The Journal of allergy and clinical immunology》2005,116(3):517-524
BACKGROUND: Chinese herbal medicine has a long history of human use. A novel herbal formula, anti-asthma herbal medicine intervention (ASHMI), has been shown to be an effective therapy in a murine model of allergic asthma. OBJECTIVE: This study was undertaken to compare the efficacy, safety, and immunomodulatory effects of ASHMI treatment in patients with moderate-severe, persistent asthma with prednisone therapy. METHODS: In a double-blind trial, 91 subjects underwent randomization. Forty-five subjects received oral ASHMI capsules and prednisone placebo tablets (ASHMI group) and 46 subjects received oral prednisone tablets and ASHMI placebo capsules (prednisone group) for 4 weeks. Spirometry measurements; symptom scores; side effects; and serum cortisol, cytokine, and IgE levels were evaluated before and after treatment. RESULTS: Posttreatment lung function was significantly improved in both groups as shown by increased FEV(1) and peak expiratory flow findings (P<.001). The improvement was slightly but significantly greater in the prednisone group (P<.05). Clinical symptom scores, use of beta(2)-bronchodilators, and serum IgE levels were reduced significantly, and to a similar degree in both groups (P<.001). T(H)2 cytokine levels were significantly reduced in both treated groups (P<.001) and were lower in the prednisone-treated group (P<.05). Serum IFN-gamma and cortisol levels were significantly decreased in the prednisone group (P<.001) but significantly increased in the ASHMI group (P<.001). No severe side effects were observed in either group. CONCLUSION: Anti-asthma herbal medicine intervention appears to be a safe and effective alternative medicine for treating asthma. In contrast with prednisone, ASHMI had no adverse effect on adrenal function and had a beneficial effect on T(H)1 and T(H)2 balance. 相似文献