计算机X线摄影适宜照射线量的探讨

目的以噪声的频率特性评价计算机X线摄影系统(computed radiography, CR)的适宜曝光量.方法在相同摄影条件下获得中速 CaWO4屏-Fuji片组合照片和CR照片,以此为基础,改变mAs,获得不同照射剂量下的CR影像,经相同的后处理条件输出它们的CR照片.用显微密度计依次对这些照片进行扫描,每张获得10万个密度值,作为离散随机信号来处理,用快速傅立叶变换计算威纳频谱(Wiener spectrum, WS),测试CR照片噪声的WS与中速CaWO4屏-Fuji片组合的照片噪声WS值相等的曝光量值.结果 (1)在照射剂量均为5.61μGy、照片密度均为1.0的情况下,在空间频率(ω)=0.1 LP/mm处,CR系统的WS值为 23.1×10 -6 mm2,屏-片系统的为20.1×10 -6 mm2;在ω=0.5 LP/mm处,CR系统的WS值为 9.73×10 -6 mm2,屏-片系统的为8.41×10 -6 mm2 .(2)当ω=0.1 LP/mm时,照射剂量为5.61μGy的CR照片的WS值分别是照射剂量为1.40、2.80、8.76、13.67、21.11μGy CR片的0.53、0.75、1.14、1.44、1.80倍;当空间频率为0.5 LP/mm时,照射剂量为5.61μGy的CR片的WS值分别是照射剂量为1.40、2.80、8.76、13.67、21.11μGy CR片的0.40、0.58、1.26、1.47、2.16倍.(3)在ω=0.5 LP/mm时,与照射剂量为5.61μGy的屏-片组合有相当的噪声水平的CR照片照射剂量大致为7.70 μGy左右.结论相同摄影条件下CR照片的噪声要比中速 CaWO4屏-Fuji片组合的大;随着照射量的增加CR系统总WS将减小,噪声下降;如想获得和屏-片相同噪声的影像,应适当增大CR系统的照射量.     

QCT骨密度测量的质量控制及意义

目的目前国内对QCT骨密度测量的质量控制研究较少，本文介绍了QCT骨密度测量的准确度、精密度试验方法和意义。方法使用东芝CT机自带体模和软件为测量工具，测量四川大学华西骨质疏松研究中心等研制的QCT骨体模（称四川体模）的骨密度值。四川体模固定于15cm深的水浴中模拟人体腰椎，东芝体模置于水浴容器与扫描床面之间，按照人腰椎QCT骨密度测量相同的条件和方法进行操作，每日1次对测量体模连续测量25日，计算SD和CV，分别以25次测量125d25次测量／1d基线作3m的shewhart图。结果测量四川体模从小到大三管骨密度分别的准确度误差为-60．4％、-39．1％和-13．6％，其分别的校正系数为2．69、1．64、1．15，相关系数为0．9966，回归方程Y=35．6＋0．958X（X为测量骨密度，Y为校正后骨密度）。本型QCT机骨密度测量的25次／1d及25次，25d精密度误差分别为1．25～5．54％和1．98～7．87％。25次125d的精密度误差要大于25次，d，显示机器一日内精密度误差变化小，随时间延长其变化增大。以25次125d的结果为基线绘制的shewhart图优于25次/d。结论一切QCT骨密度测量都应进行质量控制，准确度必须予以校正，精密度试验应在此基础上进行。这样结果才真实、科学、可靠并具有可比性。     

The AmRo study: pregnancy outcome in HIV-1-infected women under effective highly active antiretroviral therapy and a policy of vaginal delivery

OBJECTIVE: To explore pregnancy outcome in HIV-1-positive and HIV-negative women, and mother-to-child transmission (MTCT) according to mode of delivery under effective highly active antiretroviral therapy (HAART). DESIGN: Cohort of 143 pregnant HIV-1-infected women including a matched case-control study in a 2:1 ratio of controls to cases (n=98). SETTING: Academic Medical Center in Amsterdam and Erasmus Medical Center in Rotterdam, the Netherlands. POPULATION: Consecutive referred HIV-1 infected pregnant women treated with HAART and matched control not infected pregnant women. MAIN OUTCOME MEASURES: MTCT, preterm delivery, low birthweight, pre-eclampsia. RESULTS: MTCT was 0% (95% CI 0-2.1%). Seventy-eight percent of HIV-1-infected women commenced and 62% completed vaginal delivery. The calculated number of caesarean sections needed to prevent a single MTCT was 131 or more. Preterm delivery rates were 18% (95% CI 11-27) in women infected with HIV-1 and 9% (95% CI 5-13) in controls (P=0.03). HAART used at <13 weeks of gestation was associated with a 44% preterm delivery rate compared with 21% when HAART was started at or after 13 weeks and 14% in controls. (Very) low birthweight and incidence of pre-eclampsia were not different between HIV-1 and controls. CONCLUSIONS: We have not demonstrated any MTCT after vaginal delivery in women effectively treated by HAART. The HAART-associated increase in preterm delivery rate is mainly seen after first trimester HAART use.     

Resilience in Families with Children and Adult Members with Intellectual Disabilities: Tracing Elements of A Psycho‐Social Model

Aim This paper seeks to illumine how families with children and adult members with intellectual disabilities manage to manifest a buoyant and durable capacity over time. It is therefore concerned centrally with the idea of resilience. Method Drawing from diverse theoretical literatures from child development and protection and gerontology, the paper begins with a review of constructions of resilience. In an attempt to assess where there seems to be support for resilience in families, the core of the paper tests empirical evidence about positive experiences of families supporting children and adults with intellectual disabilities against the theoretical literature on resilience. Result and Conclusions The findings are used to suggest conditions under which resilience is produced and maintained, and to identify emergent elements of a psycho‐social model of resilience in families with children and adult members with intellectual disabilities.     

In vitro growth of epithelial cells from mucosa derived from different regions of the gastrointestinal tract

Attempts have been made to culture the mucosa from various parts of the gastrointestinal tract. In this study, using an explant culture method, epithelial cells have been successfully cultured from all major regions of the gastrointestinal tract. The success rate, as judged by outgrowth of epithelial cells for at least 4 weeks, varied with the tissue studied with 19/50 colonic biopsies, 5/11 small intestinal biopsies, 9/12 stomach biopsies and 42/47 gallbladder biopsies yielding outgrowth of epithelial cells. Differentiation of the epithelial cells along the mucus cell pathway could be demonstrated on the monolayer cultures using Periodic acid Schiff or Alcian blue staining. Because the cultures were very heterogeneous and many morphological cell types were present in most cultures, differentiation along the other known differentiation pathways of the gastrointestinal mucosa, such as development of absorptive cells and endocrine cells, could not be excluded.
The problem of bacterial contamination, which has hindered previous studies on tissue from these sites, was overcome by decontaminating the biopsy by soaking in dilute sodium hypochlorite (0.04%).     

优选前后精子顶体酶活性与IVF受精率相关性的研究

目的探讨优选处理前和处理后精子顶体酶活性的变化,及与体外受精(IVF)受精率的相关性。方法采用分光光度比色法,对接受IVF治疗的53例不育夫妇男方精液,分别测定优选处理前和处理后精子顶体酶活性,分析其与IVF受精率的相关性。结果优选处理后精子顶体酶活性与优选前比较有显著性差异(P<0.05);达到常规IVF标准并选择常规IVF治疗者,优选后的精子顶体酶活性与IVF受精率有相关性,精子顶体酶活性降低与IVF受精率降低有关。结论精子顶体酶活性与IVF受精率有相关性,并且通过精子顶体酶活性可以预测IVF受精率。     

计算机X射线摄影新旧成像板的比较

目的 通过体模检测和病例检查的对照研究,比较计算机X射线摄影(computed radiography,CR)新旧两种不同成像板(IP)对影像质量和病人辐射的影响,探讨新旧IP的使用原则。方法 对新旧IP进行常规暗噪声、均匀性和一致性、擦除完全性检测;根据阈值对比度-细节检测能力(TCDD)技术,75 kV时新旧IP对体模TO.16进行摄影,请3位观察者采用双盲法对所得影像进行观察评分,计算阈值检测指数H_T(A);结合临床用相同曝光条件,不同的IP分别对膝关节、胸部、腰椎进行投照,请3位放射专家进行双盲阅片,评价影像质量。结果 新旧IP在物理指标上基本相同,在相同曝光条件下,新IP的检测能力高于旧IP,当旧IP提高20%的辐射剂量后,旧IP检测能力接近新IP。结论 随着IP使用次数的增加,需逐步提高曝光剂量才能保证影像质量;若保持原有剂量不变,IP的检测能力就会下降,将影响疾病的诊断。     

手助腹腔镜与开腹肝切除术的临床对照研究

目的：探讨手助腹腔镜肝切除术的可行性及微创性。方法：随机将60例肝切除患者分为两组,30例行手助腹腔镜肝切除术,30例行开腹肝切除术,比较两组的手术时间、术中出血量、切口长度、术后肛门排气时间、术后住院时间、术后并发症、术前及术后第1、4、7天C反应蛋白（CRP）及中性粒细胞的动态变化。结果：手助腹腔镜组与开腹组的平均手术时间（114.3minvs.105.8min）和切缘距肿瘤边缘（3.22cmvs.3.33cm）差异无统计学意义（P〉0.05）。手助腹腔镜组术中平均出血量明显少于开腹组（212mlvs.376.5ml,P〈0.05）,切口长度差异有统计学意义（6.95cmvs.22cm,P〈0.01）。手助腹腔镜组术后胃肠功能恢复时间明显早于开腹组（术后肛门排气时间2.34dvs.3.48d,P〈0.05）。手助腹腔镜组住院时间明显短于开腹组（8.35dvs.10.8d,P〈0.01）。手助腹腔镜组与开腹组均无严重并发症发生。两组术后第7天CRP值比较有显著差异（23.23vs.63.35,P〈0.05）。两组于术后第4天中性粒细胞值比较有显著差异（6.45vs.9.51,P〈0.05）。结论：手助腹腔镜肝切除安全可行,并且具有创伤小、术后康复快等特点,是值得选择的微创肝切除方式。     

PET/CT图像采集时间对图像质量和病灶检出率的影响

目的探讨在不影响图像质量和病灶检出率前提下缩短PET／CT图像采集时间的可行性。方法18例接受PET／CT检查的患者，在CT扫描后按1、2、3min／床位依次进行3次PET扫描，共得到54帧图像。患者按体重分为以下3组：（1）45～60kg（7例），（2）61～75kg（7例），（3）76～90k（4例）。由2位有经验的医师共同阅片确定每例患者病变的位置和数目，图像质量由2位医师独立判断。结果3min／床位PET／CT图像上共检出127个病灶，其中最小的病灶直径约为3mm，除1min／床位图像漏检3个病灶外，其他所有病灶均能被1min／床位、2min／床位的图像识别。（1）～（3）组患者在3min／床位采集图像上识别的病灶数分别为71、41、15个，第1组患者的所有病灶在3种不同采集时间图像上均能被识别，第2组患者1min／床位采集图像遗漏了3个病灶，而2min／床位图像识别出的病灶数与3min／床位图像相同。第3组患者的所有病灶在3种采集图像上也均能被识别。1、2min／床位的PET图像质量均较3min／床位图像差，1min／床位图像质量最差，主要表现为图像本底噪声高、对比度差。3组患者中，第3组患者图像质量最差。结论对体重低于60瞻患者，1～3min的采集时间，病变的检出率无明显差异；而对体重60k以上患者，建议选择2～3min／床位的采集时间，对病情较重或不合作患者，根据需要可考虑选择1min／床位的采集时间。     

腹腔镜卵巢子宫内膜异位囊肿剔除术对卵巢控制性超促排卵的影响

目的探讨腹腔镜卵巢子宫内膜异位囊肿剔除术对卵巢控制性超促排卵(controlled ovarian hyperstimulation, COH)的影响.方法对161例(172周期)既往开腹或腹腔镜确诊的子宫内膜异位症合并不育患者行体外受精-胚胎移植术COH和助孕结局进行回顾性分析.其中42例(43周期)未行卵巢子宫内膜异位囊肿剔除术,为非囊肿剔除组;55例(59周期)曾行开腹卵巢子宫内膜异位囊肿剔除术,为开腹组;64例(70周期)曾行腹腔镜卵巢子宫内膜异位囊肿剔除术,为腹腔镜组.结果 3组间年龄、卵泡数、获卵数、受精率、优质胚胎数、移植胚胎数无显著性差异(P>0.05).非囊肿剔除组临床妊娠率41.5%(17/41),腹腔镜组33.3%(23/69),开腹组25.5%(14/55),差异无显著性(χ2=2.754,P=0.252).86例(90周期)行单侧卵巢子宫内膜异位囊肿剔除术,其中开腹组(37周期)手术侧卵巢的主导卵泡数(4.41±4.02)低于对侧卵巢(6.14±4.37)(t=-2.364,P=0.024).腹腔镜组(53周期)手术侧卵巢主导卵泡数(3.33±3.50)明显低于对侧卵巢(6.40±3.61)(t=-5.358,P=0.000).结论腹腔镜和开腹卵巢子宫内膜异位囊肿剔除术均可影响卵巢COH.