温针灸治疗儿童遗尿症的随机对照观察

目的:观察温针灸对非洲小儿遗尿的疗效。方法:将72例遗尿患儿随机分为温针灸组(41例)、对照组31例,分别进行温针和针刺治疗,按国家中医药管理局《中医病证诊断疗效标准》中判效标准评定疗效。结果:温针灸组患儿痊愈平均治疗次数与对照组差异有统计学意义,两组疗效比较差异有统计学意义。结论:温针灸对改善非洲小儿遗尿证有明显作用,其机制需要进一步探讨。     

早期胰腺癌诊断的影像学对比

胰腺癌因其位置隐秘,临床症状不典型,难以早期诊断,临床医生应重视胰腺癌的一些早期症状;上腹隐痛、持续腰背痛、不明原因的食欲减低等.利用彩超、CT、螺旋CT等无创检查,协助诊断或鉴别诊断.目前CT开展较普及,又为无创检查,因此认为CT是诊断胰腺癌较好的手段.螺旋CT则更优于一般CT,有报道：螺旋CT因尾影少、成像质量高、速度快、增强后动脉相显示更清楚,其判断胰腺癌血管侵犯的敏感性和特异性都达到100%.螺旋CT与彩超一样可作为诊断胰腺癌的一线检查手段.当影像学检查难以确定时,可行EUS检查,它是目前诊断胰腺癌敏感性、特异性最高的影像学方法之一,由于其不受肠道气体的干扰,而且探头离胰腺更近,显示也更清晰,对早期胰腺癌的诊断价值极高,可以准确地测定肿瘤大小并定位.但减少误诊及漏诊的关键,是临床医生不能忽视胰腺癌的一些非特异性表现,及时利用影像学检查作出诊断,达到早期治疗的目的.     

Iron absorption in the iron-deficient rat

Summary Iron absorption in the iron-deficient rat was compared with that in the normal rat to better understand the regulation of this dynamic process. It was found that: Iron uptake by the iron-deficient intestinal mucosa was prolonged as a result of slower gastric release, particularly when larger doses of iron were employed. The increased mucosal uptake of ionized iron was not the result of increased adsorption, but instead appeared related to a metabolically active uptake process, whereas the increased mucosal uptake of transferrin iron was associated with increased numbers of mucosal cell membrane transferrin receptors. Mucosal ferritin acted as an iron storage protein, but its iron uptake did not explain the lower iron absorption in the normal rat. Iron loading the mucosal cell (by presenting a large iron dose to the intestinal lumen) decreased absorption for 3 to 4 days. Iron loading of the mucosal cell from circulating plasma transferrin was proportionate to the plasma iron concentration. Mucosal iron content was the composite of iron loading from the lumen and loading from plasma transferrin versus release of iron into the body. These studies imply that an enhanced uptake-throughput mechanism causes the increased iron absorption in the iron-deficient rat. Results were consistent with the existence of a regulating mechanism for iron absorption that responds to change in mucosal cell iron, which is best reflected by mucosal ferritin.This work was supported by NIH Grant HL 06242. This work is in part a publication of the USDA/ARS Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston, Texas. This project has been funded in part with federal funds from the US Department of Agriculture, Agricultural Research Service under Cooperative Agreement number 58-7MN1-6-100. The contents of this publication do not necessarily reflect the views or policies of the US Department of Agriculture, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government     

超声造影剂联合高强度聚焦超声损伤兔肝VX2移植瘤的可行性研究

目的研究超声造影剂作为一种增效剂,增强高强度聚焦超声的生物学效应,损伤兔肝VX2移植瘤的可行性.方法 30只荷瘤兔随机分为二组,单纯高强度聚焦超声辐照组和联合辐照组,超声造影剂剂量为0.05 ml/kg.结果联合辐照组的辐照时间明显缩短（P＜0.05）,损伤肿瘤体积大大增加（P＜0.01）,损伤效率高于单纯高强度聚焦超声辐照组（P＜0.01）.结论超声造影剂可以提高高强度聚焦超声损伤效率,靶区组织的声学特性、组织结构或者功能状态可以影响高强度聚焦超声治疗剂量.     

超声和微泡造影剂介导细胞基因转染的实验研究

目的 探讨低频超声对细胞基因转染的作用。方法 超声治疗仪频率1MHz，脉冲重复频率100Hz，占空系数20％。质粒DNA为含编码绿荧光蛋白的pEGFP。应用荧光显微镜和流式细胞仪评价细胞基因转染率，台盼蓝染色计算细胞成活率。选用C2C12、3T3-MDEI和CHO3种细胞系为研究对象，加入DNA后辐照不同声强、时间或加入超声造影剂，观察各条件下的细胞基因转染率和成活率。结果 ①超声介导的基因转染与声强和辐射时间有关，最佳剂量为1w／cm^2 20s；②同样超声剂量，较高的声强较早达到最大基因转染率；③较低剂量时，微泡造影剂可使超声介导的基因转染提高2～3倍并可显著提高最高基因转染率。结论 低频超声可介导细胞基因转染，基因转染率不但与超声辐射剂量有关，而且同样剂量时，高声强较早达到最大基因转染率，最佳剂量是1w／cm^2 20s。同时，微泡造影剂可提高超声介导基因转染的最高转染率。     

Modeling of Melt Flow and Heat Transfer in Stationary Gas Tungsten Arc Welding with Vertical and Tilted Torches

A 3D numerical simulation was conducted to study the transient development of temperature distribution in stationary gas tungsten arc welding with filler wire. Heat transfer to the filler wire and the workpiece was investigated with vertical (90°) and titled (70°) torches. Heat flux, current flux, and gas drag force were calculated from the steady-state simulation of the arc. The temperature in the filler wire was determined at three different time intervals: 0.12 s, 0.24 s, and 0.36 s. The filler wire was assumed not to deform during this short time, and was therefore simulated as solid. The temperature in the workpiece was calculated at the same intervals using heat flux, current flux, gas drag force, Marangoni convection, and buoyancy. It should be noted that heat transfer to the filler wire was faster with the titled torch compared to the vertical torch. Heat flux to the workpiece was asymmetrical with both the vertical and tilted torches when the filler wire was fully inserted into the arc. It was found that the overall trends of temperature contours for both the arc and the workpiece were in good agreement. It was also observed that more heat was transferred to the filler wire with the 70° torch compared with the 90° torch. The melted volume of the filler wire (volume above 1750 °K) was 12 mm³ with the 70° torch, compared to 9.2 mm³ with the 90° torch.     

Splenic focal lesions as manifestation of sarcoidosis: Characterization with contrast-enhanced sonography

We report the case of a 74-year-old woman with elevated liver enzyme levels in whom abdominal sonographic examination revealed a diffusely heterogeneous liver parenchyma and multiple hypoechoic subcentimetric splenic nodules. Contrast-enhanced sonography (CEUS) revealed that the splenic focal lesions did not enhance. CT examination revealed a low-density, multinodular pattern both in the liver and in the spleen. Core biopsy of 1 hepatic nodule revealed noncaseating epithelioid cell granuloma, and the patient was diagnosed with systemic sarcoidosis. CEUS has shown to be useful in the diagnosis of focal hepatic lesions, but studies referring to splenic lesions are lacking.     

Effect of lesion boundary conditions on axial strain elastograms: a parametric study

Ultrasound elastography produces strain images of compliant tissues under quasi-static compression. When a material is compressed, there are several parameters that affect the stress-distribution and, hence, the strain distribution in the material. The state of bonding of an inclusion to the background material is a critical parameter. Heretofore, in the field of elastography, the inclusion was considered to be firmly bonded to the background material and analytical solutions were derived for the elasticity problem involving simple geometries like circular inclusion (for two dimensional [2D]) and spherical inclusion (three dimensional [3D]). Under these conditions, simple analytical expressions relating the strain contrast to the modulus contrast were derived. However, it is known that the state of bonding of some tumors to their surrounding tissues depends on the type of the lesion. For example, benign lesions of the breast are known to be loosely bonded to the surrounding tissue, while malignant breast lesions are firmly bonded. In this study, we perform a parametric study using finite element modeling (FEM) to investigate the validity of the analytical expression relating the strain contrast to the modulus contrast, when the state of bonding at the inclusion/background interface spans a large dynamic range. The results suggest that estimated modulus contrast using the analytical expression is sensitive to the region-of-interest within the inclusion that is considered in the computation of the strain contrast. By considering the inclusion region lying along the axis of lateral symmetry instead of whole region of the inclusion, the estimated modulus contrast (obtained using the analytical expression present in the literature) can be computed to within a systematic error of 10% of the actual modulus contrast. Additional estimation errors are expected to accrue in experimental and in vivo conditions.     

男性隐性梅毒患者体外受精——胚胎移植治疗的结局分析

目的 分析男性隐性梅毒患者体外受精—胚胎移植(IVF-ET)治疗的结局,为其行IVF-ET治疗知情选择提供帮助.方法 选择因女方输卵管因素不孕行IVF-ET治疗的患者45对,其中男方隐性梅毒15对(观察组),男方无梅毒感染30对(对照组),两组均行IVF-ET治疗,比较其受精率、卵裂率、优质胚胎率、临床妊娠率及胚胎种植率.结果 观察组受精率54.50％、卵裂率80.00％、优质胚胎率52.60％,明显低于对照组的83.43％、98.86％、75.60％(P均＜0.05),临床妊娠率(18.18％)及胚胎种植率(8.33％)分别低于对照组的46.67％、22.22％,但无统计学差异(P均＞0.05).结论 男性隐性梅毒患者行IVF-ET治疗时受精率降低,受精后形成胚胎、胚胎继续发育能力及种植潜能较低,故其行IVF-ET治疗前应充分知情同意.