女贞子的X射线衍射Fourier指纹图谱鉴定

目的:建立中药材女贞子新鉴定分析方法。方法:以乙醇、氯仿为提取溶剂提取中药材女贞子,采用X射线衍射Fourier谱鉴定法。结果:通过对四个中药材女贞子的乙醇、氯仿提取物实验分析比较,获得中药材女贞子的标准X射线衍射Fourier图谱及特征标记峰值。结论:X射线衍射Fourier谱鉴定法可用于中药材女贞子的分析鉴定。     

Grain size,crystalline phase and fracture toughness of the monolithic zirconia

PURPOSEThis study evaluated the relationship among translucency, crystalline phase, grain size, and fracture toughness of zirconia.MATERIALS AND METHODSFour commercial zirconia - Prettau^®Anterior^® (PA), Prettau^® (P), InCorisZI (ZI), and InCorisTZI (TZI)- were selected for this study. The bar specimens were prepared to determine fracture toughness by using chevron notched beam method with four-point bending test. The grain size was evaluated by a mean linear intercept method using a scanning electron microscope. X-ray diffraction and Rietveld refinement were performed to evaluate the amount of tetragonal and cubic phases of zirconia. Contrast ratio (CR) was measured to investigate the level of translucency.RESULTSPA had the lowest fracture toughness among other groups (P < .05). In addition, the mean fracture toughness of P was significantly less than that of ZI, but there was no difference compared with TZI. Regarding grain size measurement, PA had the largest average grain size among the groups. P obtained larger grain size than ZI and TZI (P < .05). However, there was no significant difference between ZI and TZI. Moreover, PA had the lowest CR value compared with the other groups (P < .05). This means PA was the most translucent material in this study. Rietveld refinement found that PA presented the greatest percentage of cubic phase, followed by TZI, ZI, and P, respectively.CONCLUSIONThe different approaches are used by manufacturers to fabricate various types of translucent zirconia with different levels of translucency and mechanical properties, which should be concerned for material selection for successful clinical outcome.     

深度学习重建算法在腹部CT成像中应用的体模研究

目的 探讨不同辐射剂量下深度学习图像重建算法（DLIR）相对于常规迭代重建算法（ASIR-V）对腹部体模CT图像质量的改善价值。方法 根据管电压设置100 kV组与120 kV组,每组按照容积剂量指数（CTDI_vol）不同（2、4、6、8、10、15 mGy）分为6组进行常规扫描,获得基于滤波反投影（FBP）算法的CT图像,并使用不同权重迭代重建算法（ASIR-V 50%、80%、100%）及不同等级深度学习重建算法（DLIR-L、DLIR-M、DLIR-H）进行图像重建,共获得84组图像。对比分析不同重建方式下各CTDI_vol组图像各部位CT值、噪声、信噪比（SNR）、对比噪声比（CNR）及主观评分的变化规律。图像质量主观评分比较采用Kruskal-Wallis H检验,客观指标和辐射剂量比较采用单因素方差分析及配对样本t检验。结果 同一管电压下,各CTDI_vol组不同重建条件下各部位的噪声、SNR、CNR差异均有统计学意义（F=415.39、315.30,P<0.001）,且ASIR-V 50%与DLIR-L图像的噪声、SNR、CNR差异无统计学意义（P>0.05）;主观评分之间差异均有统计学意义（100 kV组：H=13.47,P=0.036;120 kV组：H=12.99,P=0.043）,且两名医师的主观评分一致性较高（Kappa>0.70）,其中DLIR-H图像质量评分最高,DLIR-M与ASIR-V 50%图像质量主观评分基本一致;100 kV组图像质量主观评分整体较120 kV略高。以CTDI_vol为15 mGy组ASIR-V 50%图像作为参照,在满足诊断需求的前提下,低中高等级的DLIR可以分别降低辐射剂量超过30%、70%、85%。结论 DLIR算法不仅能够显著降低图像噪声、提高图像质量,而且可以在满足诊断需求的前提下有效降低辐射剂量;推荐临床应用100 kV结合中、高等级DLIR行腹部低剂量CT扫描。     

症状、CT和鼻声反射在慢性鼻窦炎组织重构诊断中的意义

目的探讨鼻塞症状、CT扫描Lund-Mackay评分和鼻声反射测量鼻黏膜充血指数与慢性鼻及鼻窦炎(chronic rhinosinusitis,CRS)组织重构程度之间的相关性,探讨三者在CRS组织重构诊断中的意义。方法选取CRS患者43例,应用视觉模拟评分(visual analogous scale,VAS)系统评价鼻塞症状;Lund- Mackay平分系统评价鼻窦CT扫描结果;鼻声反射测量获取鼻黏膜充血指数;钩突黏膜组织标本行鼻黏膜纤维化程度评分。应用统计学方法对其相关性进行分析。结果鼻塞症状严重程度与鼻黏膜纤维化程度之间无明显相关性(r=-0.046,P=0.77);CT评分与黏膜组织纤维化评分之间无相关性(r=0.132,P=0.40);鼻黏膜纤维化程度与鼻黏膜充血指数之间呈负相关(r=-0.348, P=0.022)。结论鼻黏膜充血指数能够反映病变黏膜的组织重构程度,辅助症状与CT检查指导CRS治疗策略。     

不同体位超声检查在先天性肛门直肠畸形诊断中的临床应用价值

目的 探讨抱立位、仰卧位超声检查在先天性肛门直肠畸形（CARM）术前诊断中的临床价值。方法 收集我院临床诊断为CARM患儿122例,根据Wingspread分型标准分为低位组71例和中高位组51例,术前均行抱立位超声、仰卧位超声及倒立位X线检查,测量并比较两组患儿直肠盲端至肛门隐窝皮肤距离（P-Pe间距）。以手术测量结果为标准,绘制抱立位超声、仰卧位超声、倒立位X线检查诊断CARM的受试者工作特征（ROC）曲线并分析其诊断效能;采用Kappa检验分析超声、X线测得的P-Pe间距与手术测值的一致性。结果 低位组患儿仰卧位超声、倒立位X线测得的P-Pe间距均高于手术测值（均P<0.05）,抱立位超声与手术测得的P-Pe间距比较差异无统计学意义;中高位组患儿倒立位X线测得的P-Pe间距高于手术测值（均P<0.05）,抱立位超声、仰卧位超声与手术测得的P-Pe间距比较差异均无统计学意义。抱立位超声诊断CARM的敏感性、诊断符合率分别为97.18%、96.72%,均高于倒立位X线（77.64%、86.07%）,差异均有统计学意义（均P<0.05）,与仰卧位超声的敏感性、诊断符合...     

儿童发育性髋关节脱位三维CE角的测量及其意义

目的利用CT三维重建技术(3DCT)测量发育性髋关节脱位(DDH)中心边缘角(CE角)的三维变化,为其治疗提供帮助。方法2000年12月～2003年6月应用髂骨植骨髋臼成形术、Salter术、Chiari术治疗的DDH84例(96髋),均行3DCT检查。测量不同术式术后三维CE角,比较不同术式对三维CE角的影响。结果术后三维CE角的测量结果表明,SCE明显增大(P<0.01),而且较正常组SCE增大(P<0.01);ACE明显下降(P<0.01),但植骨术和Chiari术较正常组ACE增大(P<0.01);PCE虽均获明显下降(P<0.01),但仍然大于正常,而且三组中Salter术后PCE大于植骨术和Chiari术后的PCE(P<0.01)。结论三维CE角能够更好地反映头臼包容关系;不同术式对三维CE角的影响不同。     

《1986尘肺诊断标准》读片重复性的研究

为了验证《1986尘肺诊断标准》的读片重复性,作者用集体读片方式分析读片差异、分析原因。 两次该片诊断符合程度75％;小阴影形态70％;密集度75％;分布范围65％;大阴影、胸膜斑、小阴影聚集及弥漫胸膜增厚则完全相符。 影响诊断结果相符程度的主要因素是密集度判定差异。产生差异的原因可能与标准片对比方法、胸片示局部小阴影密集度较高及混合形态阴影对判定的影响等因素有关。     

Primary Large Cell Neuroendocrine Carcinoma of the Breast: Radiologic and Pathologic Findings

Some breast neoplasms are classified as primary neuroendocrine carcinomas because they are positive for neuroendocrine markers. Although neuroendocrine carcinomas can originate from various organs of the body, primary neuroendocrine carcinomas of the breast are extremely rare. The diagnosis of primary neuroendocrine carcinoma of the breast can only be made if nonmammary sites are confidently excluded or if an in situ component can be found. Here we report a primary large-cell neuroendocrine carcinoma (LCNL) involving the left breast. Breast ultrasonography revealed a lobulated, heterogeneous, low-echoic mass in the left breast, and the lesion ap-peared as a well-defined, highly-enhancing mass on a chest computed tomography scan. Ultrasound-guided core needle biopsy was performed on the mass, and primary LCNC was confirmed by histopathologic examination.     

Effects of loading rate on strength of the proximal femur

Results from previous quasi-static mechanical tests indicate that femurs from elderly subjects fail in vitro at forces 50% below those available in a fall from standing height. However, bone is a rate-dependent material, and it is not known whether this imbalance is present at rates of loading which occur in a fall. Based on recent data on time to peak force and body positions at impact during simulated falls, we designed a high rate test of the femur in a loading configuration meant to represent a fall on the hip. We used elderly (mean age 73.5±7.4 (SD) years) and younger adult (32.7±12.8 years) cadaveric femurs to investigate whether (1) the strength, stiffness, and energy absorption capacity of the femur increases under high rate loading conditions; (2) elderly femurs have reduced strength, stiffness, and energy absorption capacity compared with younger adult femurs at this loading rate; and (3) densitometric and geometric measures taken at the hip correlate with the measured fracture loads. Femurs were scanned using dual-energy X-ray absorptiometry (DXA) and then tested to failure in a fall loading configuration at a displacement rate of 100 mm/second. The fracture load in elderly and younger adult femurs increased by about 20% with a 50-fold increase in displacement rate. However, energy absorption did not increase with displacement rate because of a twofold increase in stiffness at the higher loading rate. Age-related differences in strength and energy absorption capacity were consistent with those found previously for a displacement rate of 2 mm/second. There were moderate to strong correlations between fracture load and DXA variables, with the best correlation provided by cross-sectional area (r²=0.77) and bone mineral density (BMD) (r²=0.72) at the femoral neck. Our results indicate that, even at rates of loading applied during a fall, the estimated impact force in a fall on the hip is 35% greater than the average fracture load of the elderly femur. Moreover, the relationship we found between femoral neck BMD and fracture load indicates that an increase in femoral neck BMD of more than 20% would be required to raise the strength of the femur to the level of the impact load. As clinical trials of pharmacologic interventions have demonstrated increases in BMD of only a few percent at best, our results emphasize the continuing need for intervention strategies that focus on fall prevention and on reducing the severity of those falls that do occur.     

门脉高压症静脉曲张的CT诊断

观察经临床证实30例门脉高压症的CT表现，包括食道静脉、食道周围静脉、小网膜静脉曲张，脐周静脉、脾静脉、奇静脉及半奇静脉扩张，以及肝硬化门脉高压症的其它伴随异常。CT在判定门脉高压和食道周围静脉、奇静脉、半奇静豚系统、小网膜及后腹膜是否存在静脉曲张和范围方面有肯定意义。同时对外科手术的选择有重要的指导意义。因此，CT是诊断门脉高压各侧支静脉曲张的重要方法。