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101.
孤立性蝶窦病变的诊断与治疗   总被引:1,自引:1,他引:0  
目的;提高孤立性蝶窦病变的诊断和治疗率。方法;总结使用鼻窦内窥镜诊治孤立性蝶窦病变12例的全过程。结果:12例孤立性蝶窦病变的患者的均获准确诊断,使用鼻窦镜行经鼻腔蝶窦手术,有效率为83.3%,随访6 ̄24个月,10例无复发,复发2例二次手术后治愈;结论:孤立性蝶窦病变患者可用鼻窦内窥镜诊断与治疗。  相似文献   
102.
京剧嗓音的声学分析及音域特征   总被引:3,自引:0,他引:3  
OBJECTIVE: To get the objective acoustic parameters of the voice of Beijing Opera actors and set a foundation for the training and protection of the special professional voice. METHODS: Seventy-three (age 16-57 years) professional actors and students were asked to produce sustained comfortable vowels /a/ and /i/, and to sing two pieces of songs which were in the category of Xipi and Erhuang respectively. Dr. Speech for windows version 3.0 was used to get the acoustic parameters of the vowels and the songs. RESULTS: F0 of the vowels /a/ and /i/ of different Hangdangs were Chou (272.6 +/- 42.0) Hz (mean +/- s), (304.2 +/- 22.1) Hz; Xiaosheng (499.3 +/- 34.0) Hz, (485.4 +/- 18.7) Hz; Laosheng (335.6 +/- 60.0) Hz, (317.9 +/- 45.1) Hz; Hualian (319.0 +/- 61.3) Hz, (340.1 +/- 68.8) Hz; Laodan (427.6 +/- 47.2) Hz, (437.7 +/- 45.8) Hz; Huadan (535.8 +/- 48.8) Hz, (561.6 +/- 29.2) Hz; Qingyi (548.0 +/- 69.5) Hz, (543.5 +/- 79.3) Hz; these and other acoustic parameters of vowels such as Jitter, Shimmer and NNE were all within the normal range given by the software. The vocal range of Beijing Opera actors was from 1.7 to 2.8 oct, and most of the highest and the lowest pitches were higher than that of tenor or soprano. CONCLUSIONS: These findings may help to provide insight regarding the acoustic characteristics of the voice of Beijing Opera actors.  相似文献   
103.
目的 :测定类风湿性关节炎病人足底压 ,评价足底板的生物力学效应。方法 :12名女性类风湿性关节炎病人和 8名健康女性进行年龄和体重匹配。用 F- Scan系统进行动态足底压测量 ,Kistler床反力平台用以校正测量精确性。测量足底峰压和垂直分力 ,评价足底板的生物力学表现。结果 :类风湿性关节炎病人中足底压明显高于健康人。使用足底板后 ,足底总的峰压明显降低 ,前足、后足峰压减低 ,中足峰压增高。而垂直分力改变不大。结论 :足底板能显著降低足底压力 ,使足底压力重分布 ,减轻类风湿足痛。特殊设计的足底板对类风湿足痛的治疗能起重要的作用  相似文献   
104.
H Wu  S Qu  Y Zhang  J Deng  J Li  J Zhou 《华西医科大学学报》2000,31(3):373-375
This investigation was made with reference to the changes of serum angiotensin converting enzyme (SACE) activity in type 2 diabetes and its vascular complications. SACE activity was studied in 127 type 2 diabetic patients and 90 healthy persons by using a spectrophotometric assay. The results showed SACE activity was obviously higher in diabetic patients (459.51 +/- 175.85 U) than in healthy persons (321.14 +/- 121.27 U); SACE activity was significantly higher in type 2 diabetic patients with diabetic nephropathy (548.27 +/- 166.60 U) than in patients without diabetic nephropathy (383.2 +/- 139.00 U), but there was no difference between patients with microalbuminuria and macroalbuminuria; no statistical difference was detected in SACE activity between diabetic patients with diabetic retinopathy (465.64 +/- 178.93 U) and without retinopathy (449.07 +/- 170.04 U); SACE activity was not associated with the course of diabetes, blood pressure, blood lipid and blood glucose. These data suggest that raised SACE activity might only play a role in the initiation of type 2 diabetes and diabetic nephropathy, but not relate to the progress of diabetic nephropathy, the onset of diabetic retinopathy and hypertension.  相似文献   
105.
Urban-rural comparison of HBV and HCV infection prevalence in eastern China   总被引:6,自引:0,他引:6  
The present study was initiated to make and urban-rural comparison of the prevalence of cases positive to hepatitis B and C virus(HBV and HCV,respectively)infection markers in densely populated eastern half of China.For this purpose.10 survey sites were selected,i.e.,six sites in urban areas(the city group;Beijing,shangahi and four provincial capitals)and four sites in rural areas(the village group;one village each in Jilin and Shandong provinces,and two villages in Shaanxi Province),About 50 adult women per site volunteered to participate,from whom 494 valid bllod samples were collected.Positivities to HBsAg(HBsAg^ ),anti-HBs(anti-HBs^ )and antiHBc(anti-HBc^ )were examined by RIA methods.and that to anti-HCV(anti-HCV^ )by either EIA or RIA.Those positive to any one of the three HBV infection markers were taken as HBV infection-positive(HBV^ ).The prevalence of HBsAg^ ,HBV^ and anti-HBc^ was 8%,70%and 2.7% in the city group,and 8%,65% and 2.0%in the village group,and no significant difference was found between the two groups.The overall prevalence was 8% for HBsAg^ ,68% for HBV^ ,and 2.4% for anti-HVC^ ,The results were discussed in reference to some 20 papers each on HBV^ and anti-HCV^ prevalence in China published since(1991),The reviewing of these papers of anti-HCV was low(well below 5%),and that no substantial difference was found between the rural and urban populations.  相似文献   
106.
The geographic range of Zika virus (ZIKV) has expanded from Asia to the Americas, leading to the 2015–2016 pandemic with enhanced neurovirulence. At present, ZIKV is continuously circulating in many Southeast Asian countries. Unfortunately, the persistent evolution of ZIKV in Southeast Asia and its influence on the biological characteristics of the virus remain incompletely understood. In this study, the in vitro and in vivo properties of a new ZIKV isolate obtained from Cambodia in 2019 (CAM/2019) were characterized and compared with those of the Cambodian strain (CAM/2010). Compared with CAM/2010, the CAM/2019 virus showed similar plaque morphology and growth curves in cell cultures and induced comparable viremia and organ viral loads profiles in both BALB/c and A129 (IFNAR1−/−) mice upon intraperitoneal (i.p.) inoculation. Remarkably, the CAM/2019 virus exhibited enhanced neurovirulence in neonatal mice compared with CAM/2010, with a 74-fold reduction in the 50% lethal dose (LD50). Consistently, CAM/2019 produced higher viral loads in the brains of BALB/c neonatal mice than CAM/2010 did. Sequence alignment showed that the CAM/2019 virus has acquired 12 amino acid substitutions, several of which were found to be associated with neurovirulence. In particular, the CAM/2019 virus shared an A1204T substitution in NS2A with the Thai isolate SI-BKK02 that was isolated from a microcephaly case. Taken together, our results indicate that a ZIKV strain isolated with specific mutations has emerged in Cambodia, highlighting the need for extensive molecular and disease surveillance in Cambodia and other Asian countries.  相似文献   
107.
Compared with the nucleic acid amplification test (NATT), the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid antigen self-testing (RAST) has advantages in speed and convenience. However, little is known about people's acceptance and influencing factors for SARS-CoV-2 RAST. A cross-sectional study was conducted from April 21 to 30, 2022 in China. The χ2 test and multivariate logistic regressions were used to identify the influencing factors. The structural equation model was used to test the extended protective motivation theory (PMT) model hypotheses. Among the total of 5107 participants, 62.5% were willing to accept the SARS-CoV-2 RAST. There were significant differences in acceptance among different residences (p < 0.001), educational level (p < 0.001), occupation (p < 0.001), monthly income (p < 0.001), travel frequency (p < 0.05), and feelings about NATT (p < 0.001). Response efficacy (β = 0.05; p = 0.025) and self-efficacy (β = 0.84; p < 0.001) had a positive effect, while response cost showed a negative effect (β = −0.07; p < 0.001). The public's major concerns about SARS-CoV-2 RAST are its reliability, testing method, price, and authority. Overall, a moderate intention to use SARS-CoV-2 RAST was found among the Chinese population. The extended PMT can be used for the prediction of intention to accept the RAST. We need to take measures to increase people's acceptance of SARS-CoV-2 RAST.  相似文献   
108.
Fan  Chao  Lin  Hao  Qiu  Yingying 《Journal of digital imaging》2023,36(1):339-355
Journal of Digital Imaging - Although medical imaging is frequently used to diagnose diseases, in complex diagnostic situations, specialists typically need to look at different modalities of image...  相似文献   
109.
110.

Background

To assess the accuracy of rest and treadmill exercise first-pass radionuclide ventriculographic measurements of left ventricular ejection fraction (LVEF), 40 patients underwent treadmill exercise first-pass and bicycle exercise equilibrium radionuclide ventriculography. To determine the frequency of technically adequate treadmill exercise first-pass studies, an additional 128 consecutive patients undergoing treadmill exercise first-pass procedures during stress99mTc-labeled sestamibi myocardial perfusion studies were assessed.

Methods and Results

The treadmill exercise first-pass procedure used a multicrystal camera and an241Am point source to allow for correction of patient motion. Excellent correlations were observed between resting first-pass and resting equilibrium LVEF (r=0.91; standard error of the estimate=5.6). A high correlation was also observed between treadmill exercise first-pass and bicycle equilibrium exercise LVEF measurements (r=0.85, standard error of the estimate=7.6). Treadmill first-pass LVEF systematically underestimated the bicycle equilibrium LVEF. Intraobserver agreement for rest and exercise first-pass LVEF was high (r values of 0.98 and 0.94, respectively). Of the 168 consecutive treadmill exercise first-pass studies evaluated for technical adequacy, 21 (12.5%) were deemed technically inadequate, with most of the sources of error being avoidable. The frequency of technically adequate studies was as high (87%) in high levels of exercise (Bruce stages 3 and 4) as in lower levels (88%). The findings of this study validate the first-pass treadmill exercise LVEF measurement.

Conclusion

This procedure now provides the option for combining the information of peak treadmill exercise LVEF with measurements of exercise myocardial perfusion from the same injection of radioactivity.  相似文献   
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