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41.
42.
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
43.
The characteristic features of hamartoma in terms of discrepancies in mammographic and sonographic shapes of the mass were evaluated. We reviewed 16 pathologically proven breast hamartomas, which had undergone preoperative mammography and ultrasonography. All masses were analyzed according to ACR-BIRADS on mammography. On sonography, each mass was analyzed for size, shape, margin, internal echogenicity, and posterior acoustic enhancement. We also analyzed the echogenicity of halo, and compared the characteristic changes in the shape of hamartomas attributable to compression in mammograms and sonograms. The most common sites were at 12 o'clock in the right breast and 2 o'clock in the left. The most common mammographic findings of the hamartomas were a round shape (11/16), a circumscribed margin (13/16), internal fat densities (D4)(16/16) and radiolucent halos (14/16). The most common sonographic findings of the hamartomas were an oval shape (16/16), circumscribed margins (10/16), heterogeneous internal echogenicity (14/16), echogenic (7/16) or echolucent halos (5/16), and posterior enhancements (12/16). The characteristic feature of hamartomas was a change of the mammographic round shape mass into an elongated oval shape mass by sonography (11/11), suggesting the compressibility of hamartomas. Three of the hamartomas contained a pathologically proven internal calcification. The presence of a hamartoma was suggested by a change in a mammographic round mass with a radiolucent halo into an oval heterogeneous mass surrounded by an echogenic or echolucent halo on the sonogram. This characteristic difference between the mammographic and sonographic findings was attributed to the hamartoma compressibility, and was associated with the over-proliferation of fat containing mature normal breast tissue. 相似文献
44.
Deepika D'Cunha Burkardt Anna Zachariou Chey Loveday Clare L. Allen David J. Amor Anna Ardissone Siddharth Banka Alexia Bourgois Christine Coubes Cheryl Cytrynbaum Laurence Faivre Gerard Marion Rachel Horton Dieter Kotzot Guillermo Lay‐Son Melissa Lees Karen Low Ho‐Ming Luk Paul Mark Allyn McConkie‐Rosell Marie McDonald John Pappas Christophe Phillipe Deborah Shears Brian Skotko Fiona Stewart Helen Stewart I Karen. Temple Frederic T. Mau‐Them Ricardo A. Verdugo Rosanna Weksberg Yuri A. Zarate John M. Graham Katrina Tatton‐Brown 《American journal of medical genetics. Part A》2019,179(10):2049-2055
45.
Kim Y Kim CK Cho BH Son HH Um CM Kim OY 《Journal of biomedical materials research. Part B, Applied biomaterials》2004,70(1):82-90
The applications of dental restorative composite resins containing 2,2 bis [4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane (Bis-GMA), as a base resin, and triethylene glycol dimethacrylate (TEGDMA), as a diluent, are often limited in dentistry due to the relatively large amount of volumetric shrinkage that occurs during the curing reaction. In this study, various new resin matrices were examined for use as dental composites in order to reduce the amount of volumetric shrinkage that occurs in dental composites as a result of curing. Bis-GMA derivatives were synthesized by substituting methyl groups for hydrogen on the phenyl ring. The derivatives of TEGDMA with different chain lengths or reactive groups were also examined. The molecular structural changes in the TEGDMA derivatives were not effective in reducing the level of volumetric shrinkage. The resin matrix containing a Bis-GMA derivative and TEGDMA showed a reduced amount of volumetric shrinkage in proportion to the number of methyl groups on the phenyl rings. Polymerization with a mixture of Bis-GMA, its derivatives and a diluent is a promising strategy for obtaining a polymer with a low amount of volumetric shrinkage. A comparison of the volumetric shrinkage of dental composites containing Bis-GMA, TMBis-GMA (2,2-bis[3,5-dimethyl, 4-(2-hydroxy-3-methacryloyloxy propoxy) phenyl] propane)), and TEGDMA with that prepared from a Bis-GMA and TEGDMA mixture showed that the volumetric shrinkage reduction in the new resin was approximately 50%. Furthermore, the mechanical strength of the former was higher than that of the latter. 相似文献
46.
Immunological factors in endometriosis-associated reproductive failure: studies in fertile and infertile women with and without endometriosis 总被引:7,自引:4,他引:7
Martinez-Roman S; Balasch J; Creus M; Fabregues F; Carmona F; Vilella R; Vanrell JA 《Human reproduction (Oxford, England)》1997,12(8):1794-1799
Immunopathophysiological mechanisms in endometriosis-associated
reproductive failure were studied in appropriate populations: infertile and
fertile women with and without endometriosis. The incidence of sera
positive for any of the autoantibodies tested among infertile women with
endometriosis (n = 25) was similar to that observed in the three control
groups [unexplained infertility patients (n = 25) and fertile women with (n
= 10) and without (n = 25) endometriosis]. The mean volume of peritoneal
fluid was significantly elevated in women with endometriosis (both fertile
and infertile) as compared with patients without endometriosis (fertile or
infertile). The concentration of peritoneal fluid leukocytes and the
percentage of cells positive for macrophage markers were significantly
increased and the percentage of T lymphocytes significantly decreased in
infertile women with endometriosis but not in patients with unexplained
infertility and fertile women with endometriosis, as compared with fertile
controls without endometriosis. Macrophages from infertile patients with
endometriosis had higher sperm phagocytosis than did those from infertile
women without endometriosis or fertile subjects with or without
endometriosis. Incidences of serum and peritoneal fluid samples embryotoxic
to the in-vitro development of 2-cell mouse embryos were significantly
higher in infertile patients with endometriosis than in unexplained
infertility patients and fertile women with or without endometriosis. It is
concluded that immunological mechanisms of endometriosis-associated
infertility exist but that these peritoneal immunological factors in
infertile women with endometriosis are related to their subfertility rather
than to the presence of ectopic endometrial implants. This is supported by
the lack of immunological abnormalities observed among fertile women with
endometriosis. These immunological abnormalities are lacking in patients
with unexplained infertility.
相似文献
47.
The ileoanal J pouch: radiographic evaluation 总被引:1,自引:0,他引:1
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through. 相似文献
48.
The available data on the association between micronutrients in the blood and non-alcoholic fatty liver disease (NAFLD) are limited. To investigate the clinical implications of this relationship, we sought to identify the difference in the serum levels of vitamins A and E according to NAFLD status using data from the seventh Korea National Health and Nutrition Examination Survey. In this cross-sectional study of the Korean population, NAFLD and its severity were defined using prediction models. Differences in the prevalence and severity of NAFLD were analyzed according to serum retinol (vitamin A) and alpha (α)-tocopherol (vitamin E) levels. Serum levels of retinol and α-tocopherol were positively correlated with the prevalence of NAFLD. In most prediction models of the NAFLD subjects, serum retinol deficiency was significantly correlated with advanced fibrosis, while serum α-tocopherol levels did not differ between individuals with or without advanced fibrosis. Similar trends were also noted with cholesterol-adjusted levels of α-tocopherol. In summary, while circulating concentrations of retinol and α-tocopherol were positively associated with the presence of NAFLD, advanced liver fibrosis was only correlated with serum retinol levels. Our findings could provide insight into NAFLD patient care at a micronutrient level. 相似文献
49.
Nguyen Minh Hai Nguyen Dang Dung Dinh Cong Pho Vu Tung Son Vu Ngoc Hoan Phan Tan Dan Bui Dang The Anh La Huong Giang Pham Ngoc Hung 《Vaccine》2021,39(7):1140-1147
BackgroundROTAVAC® is derived from human 116E rotavirus (RV) neonatal strain. In this study, we evaluated the immunogenicity, safety and reactogenicity of ROTAVAC® in Vietnam.MethodWe conducted a phase IV clinical trial in healthy infants aged 6–8 weeks using the complete regimen of ROTAVAC® with three doses. Serum anti-RV IgA was measured by enzyme-linked immunosorbent assay to assess the geometric mean concentration in infants who received the complete regimen of the vaccine.ResultsA total of 360 participants were enrolled in this clinical trial. The mean age ± standard deviation at enrollment was 6.9 ± 0.6 weeks. The anti-RV IgA titer was 4.01 ± 3.74 mg/ml pre-vaccination and substantially increased to 29.27 ± 80.64 mg/ml post-vaccination. The value of logIgA significantly increased (p = 0.003) from 0.28 ± 0.79 to 1.03 ± 0.54. The proportion of participants with equal to and greater than 3-fold and 4-fold shifts in pre- to post-vaccination antibody titer (IgA) were 55.4% and 48.3%, respectively. No adverse events or serious adverse events were recorded immediately within 30 min after the administration of each dose. The most common adverse events within 14 days after each visit were fever, unusual crying and irritability. Other adverse events occurred at a low rate, and no case of intussusception was noted.ConclusionsThe complete regimen of ROTAVAC® demonstrated an immunological response with clinically acceptable safety profile. Post-completion of this study, ROTAVAC® is now a WHO-prequalified vaccine and available in Vietnam. 相似文献
50.
Biomechanical assessment with electromyography of post-stroke ankle plantar flexor spasticity 总被引:1,自引:0,他引:1
Spasticity has been defined as a motor disorder characterized by a velocity-dependent increase in tonic stretch reflex (muscle tone). Muscle tone consists of mechanical-elastic characteristics, reflex muscle contraction and other elements. The aims of this study were to determine whether to assess spasticity quantitatively, and to characterize biomechanical and electromyographic spasticity assessment parameters. These assessment parameters were described by investigating the correlation between clinical measures and the response to passive sinusoidal movement with consecutive velocity increments. Twenty post-stroke hemiplegic patients and twenty normal healthy volunteers were included in the study. Five consecutive sinusoidal passive movements of the ankle were performed at specific velocities (60, 120, 180, and 240 degrees/ sec). We recorded the peak torque, work, and threshold angle using a computerized isokinetic dynamometer, and simultaneously measured the rectified integrated electromyographic activity. We compared these parameters both between groups and between different velocities. The peak torque, threshold angle, work, and rectified integrated electromyographic activity were significantly higher in the post-stroke spastic group at all angular velocities than in the normal control group. The threshold angle and integrated electromyographic activity increased significantly and linearly as angular velocity increased, but the peak torque and work were not increased in the post-stroke spastic group. Peak torque, work, and threshold angle were significantly correlated to the Modified Ashworth scale, but the integrated electromyographic activity was not. The biomechanical and electromyographic approach may be useful to quantitatively assess spasticity. However, it may also be very important to consider the different characteristics of each biomechanical parameter. 相似文献