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111.
Autopsy findings of missed diagnoses that would probably have changed management or prognosis occur in up to 29% of cases in general hospitals. Such proportions may be higher in subsets of patients with complex diseases. We reviewed 2908 consecutive autopsies performed over a period of 29 months in a large-volume hospital, analyzing 118 autopsies of patients with hematological malignancies or severe aplastic anemia. A review of macroscopic reports as well as microscopic examination of tissue samples was performed. Medical records were reviewed for clinical diagnoses. Discordances between clinical and autopsy diagnoses were classified using Goldmans criteria. Additionally, we searched for clinical parameters correlated with occurrence of class-I discrepancy using a multivariate method. Median age was 46.5 years, and 25.4% had received a hematopoietic stem-cell transplant. Overall, 11.9% (6.6–19.1%) of patients died before conclusion of the hematological diagnosis and 33% (24.6–42.3%) died with no active hematological disease. We found class-I discrepancy in 31.3% (23.1–40.5 %) of cases. The most common among these diagnoses were hematological disease, pneumonia and gastrointestinal bleeding. In a univariate analysis, being elderly (P=0.04) was positively correlated with the finding of class-I discrepancies; while, having received previous specific hematological treatment (P=0.0005) or hematopoietic stem-cell transplants (P=0.013), or being admitted to a specialized hematology unit (P=0.0006) were negatively correlated to the occurrence of such discrepancies. Multivariate analysis showed that care in a specialized hematology unit (OR 0.34, 0.12–0.93) was independently associated with lower occurrence of discrepancies. We concluded that critical diagnoses are often missed in highly complex hematological patients especially in the absence of admission to specialized hematology units.  相似文献   
112.
The autopsy is in decline, despite the fact that accurate mortality statistics remain essential for public health and health service planning. The falling autopsy rate combined with the Coroners Review and Human Tissue Act have contributed to this decline, and to a falling use of autopsy histology, with potential impact on clinical audit and mortality statistics. At a time when the need for reform and improvement in the death certification process is so prominent, we felt it important to assess the value of the autopsy and autopsy histology. We carried out a meta-analysis of discrepancies between clinical and autopsy diagnoses and the contribution of autopsy histology. There has been little improvement in the overall rate of discrepancies between the 1960s and the present. At least a third of death certificates are likely to be incorrect and 50% of autopsies produce findings unsuspected before death. In addition, the cases which give rise to discrepancies cannot be identified prior to autopsy. Over 20% of clinically unexpected autopsy findings, including 5% of major findings, can be correctly diagnosed only by histological examination. Although the autopsy and particularly autopsy histology are being undermined, they are still the most accurate method of determining the cause of death and auditing accuracy of clinical diagnosis, diagnostic tests and death certification.  相似文献   
113.
目的:应用串联质谱(tandem mass spectrometry, MS/MS)技术进行遗传代谢病(IEM)高危儿筛查,初步了解我国 IEM 的发病种类和阳性率,为其有效防治提供科学依据。方法:利用MS/MS技术对在河北省石家庄市8所省、市级医院就医的552例可疑 IEM 患儿的血液样本进行 IEM 筛查。结果:发现阳性患儿64例,阳性率为11.6%。其中甲基丙二酸血症或丙酸血症33例,苯丙酮尿症2例,肉碱棕榈酰转移酶缺乏Ⅰ型3例,长链酰基辅酶 A 脱氢酶缺乏症1例,中链酰基辅酶A脱氢酶缺乏症2例,枫糖尿症6例,短链酰基辅酶A脱氢酶缺乏症2例,戊二酸血症Ⅰ型2例,异戊酸血症2例,同型胱氨酸尿症2例,肉碱缺乏症4例,酪氨酸血症1例,精氨酸琥珀酸尿症1例,瓜氨酸血症2例,精氨酸血症1例。结论:MS/MS技术是筛查诊断IEM的有效工具。  相似文献   
114.
115.
目的分析在兆伏级电子计算机断层扫描(MVCT)图像引导下采用螺旋断层调强放疗技术治疗胰腺癌患者的摆位误差,并计算计划靶区(PTV)的边界(margin)外放。方法行MVCT图像扫描,将扫描获取的MVCT图像与计划CT图像进行配准,记录左右(X)、头脚(Y)、腹背(Z)轴方向和横断面旋转(roll)方向的误差值,并对误差值进行分析计算。结果共行592次MVCT扫描。X、Y、Z和roll方向摆位误差值分别为(-0.5±2.8)mm、(-1.1±6.4)mm、(6.0±4.4)mm和(-0.2±0.7)°。X、Y和Z 3个方向上的平均误差小于5 mm,所占比例分别为97.13%(575/592)、88.01%(521/592)和37.84%(224/592),roll方向旋转误差小于1°,所占比例为93.92%(556/592)。根据公式得出在X、Y和Z 3个方向PTV的边界外放间距值分别为5.2、9.9和7.5 mm。结论对MVCT图像引导下行螺旋断层放射治疗胰腺癌患者的摆位误差数据分析,为提高放射治疗精度及疗效,推荐胰腺癌放疗在X、Y和Z三维方向上CTV到PTV的margin外放值分别为5、10和8 mm。  相似文献   
116.
本文探讨琥珀酸半醛脱氢酶(succinic semialdehyde dehydrogenase,SSADH)缺陷病各尿液标志物的气相色谱-质谱法(Gas Chromatography-Mass Spectrometry,GC-MS)分析特征。收集SSADH患儿的尿液标本,经去尿素、加内标(正十七酸)、除蛋白、真空干燥处理,残余物进行三甲基硅烷化衍生后进样行GC-MS法分析。尿液中可检测到明显的4-羟基丁酸、2,4-二羟基丁酸、3,4-二羟基丁酸和4,5-二羟基己酸信号。在TIC图上,其绝对保留时间(相对保留时间)分别是6.32min(0.434),7.80min(0.536),7.94min(0.546),8.80min,8.90min(0.605,0.612)。在质谱图上,其特征离子(m/z,TMS)分别是M-15(233,2),M-15(321,3),M-15(321,3),M-15(349,3)。GC-MS法分离鉴定尿液代谢成分,可作为诊断该病的一种可靠手段。  相似文献   
117.
目的:研究采用电子射野系统评价头颈部肿瘤患者摆位误差时的观察者间变异和观察者自身变异。方法:两队研究小组,分别由四名医师和四名技师组成,两组分别对6名头颈部肿瘤的患者,采用电子射野影像仪(electronic portal imaging device,EPID)拍摄验证片(electronic portal images,EPIs),在EPIs上勾画骨性标志,以放疗计划生成的数字重建图像(digitally reconstructed radiographs,DRRs)做为参考图像,定量分析不同观察研究人员之间和研究人员自身采用EPID确定头颈部肿瘤患者的射野摆位误差(field placement errors,FPEs)的差异性。结果:在前/后位射野图像上.不同医师之间、医师自身及技师自身对摆位误差的判断无明显差异,但在技师之间出现了明显的自身差异性.医师组和技师组在前/后射野图像上的均方根(root-mean—square,RMS)分别为2.52±0.46和3.43±0.43,两者具有明显差异;在侧位野图像上,医师自身对摆位误差的判断有较好的稳定性,但部分不同医师之间在腹背、头足方向上部分患者中出现差异,而不同的技师之间存在明显差异性,医师组和技师组在侧位射野图像上的RMS分别为2.72±0.16和2.62±0.22.两者无明显差异。结论:医师和技师组在采用电子射野系统对头颈部摆位误差进行判断时存在人员之间的误差,应对所有人员进行统一训练才能减少射野摆位误差,从而提高IMRT治疗效果。  相似文献   
118.
The dynamic and distributed work environment in critical care requires a high level of collaboration among clinical team members and a sophisticated task coordination system to deliver safe, timely and effective care. A complex cognitive system underlies the decision-making process in such cooperative workplaces. This methodological review paper addresses the issues of translating cognitive research to clinical practice with a specific focus on decision-making in critical care, and the role of information and communication technology to aid in such decisions. Examples are drawn from studies of critical care in our own research laboratories. Critical care, in this paper, includes both intensive (inpatient) and emergency (outpatient) care. We define translational cognition as the research on basic and applied cognitive issues that contribute to our understanding of how information is stored, retrieved and used for problem-solving and decision-making. The methods and findings are discussed in the context of constraints on decision-making in real-world complex environments and implications for supporting the design and evaluation of decision support tools for critical care health providers.  相似文献   
119.
120.
胰腺癌患者螺旋断层放疗摆位误差分析   总被引:1,自引:0,他引:1  
目的:通过兆伏级CT(MVCT)在线测量校正胰腺癌患者螺旋断层放疗的摆位误差,确定临床靶区CTV和计划靶区PTV之间的外放距离。方法:2012年5月至12月,21例接受TomoTherapy治疗的胰腺癌患者,每次治疗前均行靶区部位MVCT扫描。并将扫描后的MVCT图像与定位时千伏级CT(kVCT)图像进行配准,分别记录患者左右x、头脚y、腹背z和横断面旋转Roll四个方向的偏差数值,对其误差值进行统计分析。结果:21例患者共行358次MVCT扫描,其摆位误差值在x、y、z和Roll方向分别为:(-0.14±0.60)mm、(-1.21±0.44)mm、(0.69±0.93)mm和(0.02±0.26)。x、y、z方向CTV和PTV之间的外放距离分别为:5.5mm、7.4mm和3.9mm。结论:胰腺癌患者治疗摆位误差较大,Tomotherapy通过在线摆位校正能有效减小摆位误差。临床上建议胰腺癌患者在x、y、z方向上CTV和PTV之间可分别外扩5mm、7mm和4mm,为精确照射提供必要的质量保证。  相似文献   
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