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41.
摘要 目的:探讨胸部CT结合AI诊断系统对疑似肺结节患者的诊断及对结节类型的评估价值。方法:选取2019年12月-2020年12月在我院进行CT检查的358例疑似肺结节患者,将其按照随机数字表法分为两组:对照组(放射科医生根据CT扫描结果,通过人工阅片分析记录检出结节数量和影像特征),观察组(将CT扫描结果导入AI辅助诊断系统,经AI运算得到结节检出数量和影像特征)。AI辅助系统IMsight用于肺结节的图像分析和自动检测。通过组织病理学确定结节的良恶性。绘制受试者工作特征曲线(ROC)曲线以评估AI和CT结合图像的诊断价值。结果:病理结果最后确诊结节数量736个,恶性结节139个(18.89 %),良性结节597个(81.11 %)。观察组诊断结节数量717个,检出率97.42%,对照组诊断出结节数量603个,检出率81.93 %。观察组较对照组的结节检出率、阳性检出率升高(P<0.05),漏检率和假阴性率均显著降低(P<0.05)。当结节小于10 mm时,观察组较对照组的检出率升高(P<0.05),观察组较对照组对磨玻璃密度结节和实性结节检出率升高(P<0.05),观察组较对照组位于胸膜结节检出率升高(P<0.05)。观察组较对照组AUC(P<0.05),表明AI系统下的结节检出准确率高。ROC曲线显示观察组的敏感性和特异性分别为88.39%和89.68 %,对照组的敏感性和特异性分别为75.24 %和82.34 %,观察组较对照组的ROC曲线敏感性和特异性升高(P<0.05)。结论:AI辅助诊断系统可有效提高肺结节的检出率,减少误检率及漏检率,值得在肺结节CT检测中应用推广。  相似文献   
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43.
目的:探讨常规腹部立位平片漏诊膈下游离气体的原因及技术改进。方法:15例疑有气腹但腹部立位平片阴性者加拍胸部正位片,观察有无膈下游离气体。结果:15例中12例胸片可显示膈下少量游离气体。结论:X线投照中心线位置不同会影响膈下游离气体的显示,胸片较腹部立位平片更容易显示少量气腹。  相似文献   
44.
目的:评估重症监护室的重症感染或者脓毒性休克患者尿常规检查和胸部X线检查的准确性。方法:回顾性分析我院进入重症监护室的确诊为重症感染或者脓毒性休克的患者,收集所有入组患者的个人情况,进入监护室以后的尿液检查结果、胸部X线检查结果,以及体液细菌学培养的结果,分析上述数据与诊断泌尿系感染或者肺部感染之间关系。结果:我们回顾了400例患者,其中70例患者确诊为重症感染或者脓毒性休克,其中13例患者确诊为泌尿系感染(尿常规,白细胞>10/高倍镜视野),敏感性和特异性分别为81%(95%CI 0.67-0.92)和65%(95%CI 0.51-0.75);36例患者确诊为肺部感染,胸部X线检查诊断肺部感染的的敏感性和特异性分别为57%(95%CI 0.45-0.69)和92%(95%CI 0.82-0.93)。结论:对于脓毒血症或者脓毒性休克的患者,胸部X线检查敏感性较低,这可能与肺部X线检查干扰因素较多,并且肺部感染发生到出现影像学变化有一定的时间间隔;而尿液分析敏感性较高,但是也可能由于尿液中上皮细胞的存在而干扰诊断。  相似文献   
45.
虽然胸部创伤的处理方法复杂多样,但随着多层螺旋CT的应用以及低侵入性诊断手段如电视辅助胸腔镜和血管内修复技术的发展,胸部创伤的诊断与治疗正变得相对快捷和详尽。近年来,体外膜肺氧合(ECMO)疗法进一步降低了胸部创伤患者的死亡率。本文将就不同胸部创伤及对机体的影响、相关诊断与处理的临床研究进展进行综述。  相似文献   
46.
The respiratory muscles constitute the respiratory pump, which determines the efficacy of ventilation. Any functional disorder in their performance may cause insufficient ventilation. This study was designed to quantitatively explore the relative contribution of major groups of respiratory muscles to global lung ventilation throughout a range of maneuvers in healthy subjects. A computerized experimental system was developed for simultaneous noninvasive measurement of inspired/expired airflow, mouth pressure and up to 8 channels of EMG surface signals from major respiratory muscles which are located near the skin (e.g., sternomastoid, external intercostal, rectus abdominis and external oblique) during various respiratory maneuvers. Lung volumes values were calculated by integration of airflow data. Hill's muscle model was utilized to calculate the forces generated by the muscles from the acquired EMG data. Analysis of EMG measurements and respiratory muscles forces revealed the following characteristics: (a) muscle activity increased with increased breathing effort, (b) inspiratory muscles contributed to inspiration even at relatively low flow rates, while expiratory muscles are recruited at higher flow rates, (c) the forces generated by the muscle depended on the muscle properties as well as on their EMG performance and (d) the pattern of the muscle's force curves varied between subjects, but were generally consistent for the same subject regardless of breathing effort.  相似文献   
47.
PurposeThe evaluation of clinical image quality (IQ) is important to optimize CT protocols and to keep patient doses as low as reasonably achievable. Considering the significant amount of effort needed for human observer studies, automatic IQ tools are a promising alternative. The purpose of this study was to evaluate automatic IQ assessment in chest CT using Thiel embalmed cadavers.MethodsChest CT’s of Thiel embalmed cadavers were acquired at different exposures. Clinical IQ was determined by performing a visual grading analysis. Physical-technical IQ (noise, contrast-to-noise and contrast-detail) was assessed in a Catphan phantom. Soft and sharp reconstructions were made with filtered back projection and two strengths of iterative reconstruction. In addition to the classical IQ metrics, an automatic algorithm was used to calculate image quality scores (IQs). To be able to compare datasets reconstructed with different kernels, the IQs values were normalized.ResultsGood correlations were found between IQs and the measured physical-technical image quality: noise (ρ = −1.00), contrast-to-noise (ρ = 1.00) and contrast-detail (ρ = 0.96). The correlation coefficients between IQs and the observed clinical image quality of soft and sharp reconstructions were 0.88 and 0.93, respectively.ConclusionsThe automatic scoring algorithm is a promising tool for the evaluation of thoracic CT scans in daily clinical practice. It allows monitoring of the image quality of a chest protocol over time, without human intervention. Different reconstruction kernels can be compared after normalization of the IQs.  相似文献   
48.
本文分析了济南、青岛1962—2000年7—18岁儿童少年生长发育的长期变化趋势。38年间,济南市7—18岁男女生身高平均增长15 48cm(男)、12 09cm(女),体重平均增长15 76kg(男)、10 01kg(女),胸围平均增长7 88cm(男)、4 10cm(女);青岛市7—18岁男女生身高平均增长17 12cm(男)、13 19cm(女),体重平均增长16 98kg(男)、10 46kg(女),胸围平均增长6 72cm(男)、3 05cm(女)。青岛市男女生身高的增长幅度显著大于济南。  相似文献   
49.
This study combined surface electromyography with panoramic ultrasound imaging to investigate whether non-uniform excitation could lead to acute localized variations in cross-sectional area and muscle thickness of the clavicular and sternocostal heads of pectoralis major (PM). Bipolar surface electromyograms (EMGs) were acquired from both PM heads, while 13 men performed four sets of the flat and 45° inclined bench press exercises. Before and immediately after exercise, panoramic ultrasound images were collected transversely to the fibers. Normalized root mean square (RMS) amplitude and variations in the cross-sectional area and muscle thickness were calculated separately for each PM head. For all sets of the inclined bench press, the normalized RMS amplitude was greater for the clavicular head than the sternocostal head (P < 0.001), and the opposite was observed during the flat bench press (P < 0.001). Similarly, while greater increases in cross-sectional area were observed in the clavicular than in the sternocostal head after the inclined bench press (P < 0.001), greater increases were quantified in the sternocostal than in the clavicular head after the flat bench press exercise (P = 0.046). Therefore, our results suggest that the PM regional excitation induced by changes in bench press inclination leads to acute, uneven responses of muscle architecture following the exercise.  相似文献   
50.
Sujiang pigs are a synthetic breed derived from Jiangquhai, Fengjing, and Duroc pigs. In this study, we sequenced the genome of 62 pigs with a coverage depth of 10× to 20×, including 27 Sujiang and 35 founder breed pigs, and we collected 360 global pigs’ genome sequence data from public databases including 39 Duroc pigs. We obtained a high-quality variant dataset of 365 Sujiang pigs by imputing the porcine 80 K single nucleotide polymorphism (SNP) Beadchip to the whole-genome scale with a total of 422 pigs as a reference panel. A dataset of 365 imputated Sujiang pigs was used to perform single-trait genome-wide association study (GWAS) and meta-analyses for growth and fatness traits. Single-trait GWAS identified 1 907, 18, and 14 SNPs surpassing the suggestively significant threshold for backfat thickness, chest circumference, and chest width, respectively. Meta-analyses identified 2 400 genome-wide significant SNPs and 520 suggestively significant SNPs for backfat thickness and chest circumference, and 719 genome-wide significant SNPs and 1 225 suggestively significant SNPs for all seven traits. According to the meta-analysis of backfat thickness and chest circumference, a remarkable region of 2.69 Mb on Sus scrofa chromosome 4 containing FAM110B, IMPAD1, LYN, MOS, PENK, PLAG1, SDR16C5 and XKR4 was identified as a candidate region. The haplotype heat map of the 2.69 Mb region verified that Sujiang pigs were derived from Duroc and Chinese indigenous pigs, especially Jiangquhai pigs. The Kruskal-Wallis test showed that haplotypes of the 2.69 Mb region significantly affected backfat thickness and chest circumference traits. We then focused on PLAG1, an important growth-related gene, and identified two synonymous SNPs with obvious differences among different breeds in the PLAG1 gene. We then performed genotyping of 365 Sujiang, 150 Duroc, 95 Jiangquhai, and 100 Fengjing pigs to confirm the above result and verified that the two variants significantly affected phenotypes of growth and fatness traits. Our findings not only provide insights into the genetic architecture of porcine growth and fatness traits but also provide potential markers for selective breeding of these traits in Sujiang pigs.  相似文献   
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