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991.
《Journal of pediatric surgery》2023,58(5):856-861
Background/PurposeA small number of Hirschsprung disease (HD) patients develop inflammatory bowel disease (IBD)-like symptoms after pullthrough surgery. The etiology and pathophysiology of Hirschsprung-associated IBD (HD-IBD) remains unknown. This study aims to further characterize HD-IBD, to identify potential risk factors and to evaluate response to treatment in a large group of patients.MethodsRetrospective study of patients diagnosed with IBD after pullthrough surgery between 2000 and 2021 at 17 institutions. Data regarding clinical presentation and course of HD and IBD were reviewed. Effectiveness of medical therapy for IBD was recorded using a Likert scale.ResultsThere were 55 patients (78% male). 50% (n = 28) had long segment disease. Hirschsprung-associated enterocolitis (HAEC) was reported in 68% (n = 36). Ten patients (18%) had Trisomy 21. IBD was diagnosed after age 5 in 63% (n = 34). IBD presentation consisted of colonic or small bowel inflammation resembling IBD in 69% (n = 38), unexplained or persistent fistula in 18% (n = 10) and unexplained HAEC >5 years old or unresponsive to standard treatment in 13% (n = 7). Biological agents were the most effective (80%) medications. A third of patients required a surgical procedure for IBD.ConclusionMore than half of the patients were diagnosed with HD-IBD after 5 years old. Long segment disease, HAEC after pull through operation and trisomy 21 may represent risk factors for this condition. Investigation for possible IBD should be considered in children with unexplained fistulae, HAEC beyond the age of 5 or unresponsive to standard therapy, and symptoms suggestive of IBD. Biological agents were the most effective medical treatment.Level of EvidenceLevel 4 相似文献
992.
目的:根据镍钛记忆合金的特性,设计一款操作简便,支撑力强的股骨头支撑器,用以治疗成人股骨头缺血性坏死。方法:采用记忆合金板材通过线切割、毛坯光整、热成型、热处理等工艺流程制成股骨头支撑器,并生产相应的手术器械。然后对股骨头支撑器进行有限元静态和载荷分析。结果:静态应力分析结果显示,最大应力为1500 MPa。位移变形分析显示,最大位移为1.75mm。结论:根据有限元分析,伞状记忆合金股骨头支撑器微创治疗股骨头坏死,符合股骨头的生物力学优势,可起到预防股骨头塌陷的作用。 相似文献
993.
腰椎间盘退变引起的下腰痛是影响人们健康的重要原因,MRI 技术是诊断腰椎间盘退变的主要手段,特别是MR扩散加权成像、T2 mapping成像、T1ρ加权成像、钠MRI、软骨延迟钆增强MRI 和MR 波谱成像等新技术能够通过对蛋白聚糖、水等椎间盘细胞外基质成分进行检测,从而达到早期诊断腰椎间盘退行性变的目的。从上述几个方面综合论述MRI技术用于定量分析研究早期腰椎间盘退变的新进展,并就各自的优缺点进行比较。 相似文献
994.
目的:通过回顾性分析11例不典型肾上腺腺瘤的C T影像特征及误诊原因,以提高诊断准确率。方法收集近几年经手术病理确诊的不典型肾上腺腺瘤11例,均行C T平扫及三期增强扫描,结合临床资料进行回顾性分析。结果11例肾上腺腺瘤中,高强化腺瘤2例,肿块最大径>4cm的大腺瘤8例,双侧腺瘤1例。高强化腺瘤在C T增强表现为快进快退;大腺瘤中囊性密度和强化较低的2例,肿瘤内出血的无功能肾上腺瘤1例,CT增强表现为快进快退伴偏心囊变的5例,双侧高强化的肾上腺腺瘤1例。结论详细分析不典型肾上腺腺瘤的CT特征,密切联系临床病史、实验室结果和M RI检查,可提高不典型肾上腺腺瘤的诊断准确率。 相似文献
995.
杨海帆 《航空航天医学杂志》2014,(7):906-907
目的研究α1肾上腺素能受体阻滞剂萘哌地尔在NBP(慢性非细菌性前列腺炎)的临床治疗上是否安全有效。方法采取多中心、开放的临床研究方法,选取110例NBP患者并对其治疗四个星期。治疗所获得的各项指标均按照EPS(美国国立卫生院前列腺液)WBC计数及最大尿流量、NIH-CPSI(慢性前列腺炎症状评分)作为参考指标,对该药物的安全性以及有效性进行测评。结果在四周的治疗之后,110例患者中有109例可进行评价。全组患者治疗前后的生活质量评分平均降低4.1分,症状评分平均降低了7.9分,NIH-CPSI总评分平均降低了12.0分。治疗前后的MFR分别为(19.24-4.8)、(22.74-4.9)mL/s。EPS中治疗前及治疗后的WBC计数分别为(15.24-15.1)、(9.54-12.0)个/HP。若评价标准为病人的症状改善情况,则17例患者治疗无效约占总体的15.6%,56例患者治疗有效约占总体51.4%,33例患者治疗显效约占总体30.3%,3例患者治愈约占总体的2.7%。治疗的总有效率为84.4%。在治疗过程中有2两例患者出现食欲不振,4例患者出现轻度头晕的症状,总体不良事件发生率为3.81%。结论可见萘哌地尔在临床治疗慢性非细菌性前列腺炎上有效、安全。 相似文献
996.
Seunggyun Ha Hongyoon Choi Gi Jeong Cheon Keon Wook Kang June-Key Chung Euishin Edmund Kim Dong Soo Lee 《Nuclear Medicine and Molecular Imaging》2014,48(4):278-286
Purpose
Texture analysis on 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) scan is a relatively new imaging analysis tool to evaluate metabolic heterogeneity. We analyzed the difference in textural characteristics between non-small cell lung carcinoma (NSCLC) subtypes, namely adenocarcinoma (ADC) and squamous cell carcinoma (SqCC).Methods
Diagnostic 18F-FDG PET/computed tomography (CT) scans of 30y patients (median age, 67; range, 42-88) with NSCLC (17 ADC and 13 SqCC) were retrospectively analyzed. Regions of interest were manually determined on selected transverse image containing the highest SUV value in tumors. Texture parameters were extracted by histogram-based algorithms, absolute gradient-based algorithms, run-length matrix-based algorithms, co-occurrence matrix-based algorithms, and autoregressive model-based algorithms. Twenty-four out of hundreds of texture features were selected by three algorithms: Fisher coefficient, minimization of both classification error probability and average correlation, and mutual information. Automated clustering of tumors was based on the most discriminating feature calculated by linear discriminant analysis (LDA). Each tumor subtype was determined by histopathologic examination after biopsy and surgery.Results
Fifteen texture features had significant different values between ADC and SqCC. LDA with 24 automate-selected texture features accurately clustered between ADC and SqCC with 0.90 linear separability. There was no high correlation between SUVmax and texture parameters (|r| ≤ 0.62).Conclusion
Each subtype of NSCLC tumor has different metabolic heterogeneity. The results of this study support the potential of textural parameters on FDG PET as an imaging biomarker. 相似文献997.
该文尝试揭示军事医学人才评价系统的本质特征和运动规律,分析了军事医学环境、人才竞争环境、政策制度环境对评价系统的影响,探讨了评价主体、评价客体、评价活动组成的系统结构及相互关系,阐述了评价的价值评估与判断功能、选择功能、导向功能、调控功能、监督功能以及功能间的自洽机制,讨论了评价系统特征和系统演化规律。 相似文献
998.
The influence of premedication on heart rate variability 总被引:7,自引:0,他引:7
D. Michaloudis G. Kochiadakis G. Georgopoulou O. Fraidakis G. Chlouverakis A. Petrou & B. J. Pollard 《Anaesthesia》1998,53(5):446-453
Analysis of heart rate variability has been used to study the effects of midazolam, morphine and clonidine on the autonomic nervous system, when administered to patients for premedication. Ninety-five patients were studied 60 min before and 60 min after premedication. Normal saline ( n = 25), midazolam 0.08 mgkg−1 ( n = 24), morphine 0.15 mgkg−1 ( n = 23), or clonidine 2 μgkg−1 ( n = 23) were administered intramuscularly by random allocation. A Holter device was connected to the patient during the study period. Using power spectral analysis the low-frequency and high-frequency components were calculated from the Holter recordings. These are markers for sympathetic and parasympathetic activity respectively; the low- to high-frequency ratio was also calculated, a ratio of >1 signifying sympathetic dominance. A significant reduction was noticed in both low-frequency and high-frequency power in the three premedicated groups, whereas no changes were observed in the normal saline group. In the case of midazolam, both the low and high frequencies were decreased but the low- to high-frequency ratio did not change significantly. Morphine and clonidine depressed the low-frequency component more than the high-frequency component and the low- to high-frequency ratio was decreased, suggesting parasympathetic dominance. We conclude that heart rate variability may be a useful tool for investigating the effect of drugs on the autonomic nervous system. 相似文献
999.
Two numerical techniques for solving optimal periodic control problems with a free period are developed. The first method uses shooting techniques for solving an appropriate boundary value problem associated with the necessary conditions of the minimum principle. A convenient form of the transversality condition for the free period is incorporated. The second method is a direct optimization method that applies non-linear programming techniques to a discretized version of the control problem. Both numerical methods are illustrated in detail by a non-convex economic production planning problem. In this model, the π-test reveals that the steady-state operation is not optimal. The optimal periodic control is computed such that a complete set of necessary conditions is verified. The solution techniques are extended to obtain the optimal periodic control under various state constraints. A sensitivity analysis of the optimal solution is performed with respect to a specific parameter in the model. © 1998 John Wiley & Sons, Ltd. 相似文献
1000.
Organ transplantations are among the most expensive surgical treatments performed today, but estimates of the costs of organ transplantations vary widely between settings. The aim of this study is to estimate the costs of renal, liver and heart transplantation in a university hospital, adopting a similar costing methodology for all the three kinds of transplantation. Resource use data were collected from 803 patients transplanted between January 1995 and August 2001. Data about the time physicians and other hospital employees spent per transplantation were based on interviews. All costs from pretransplantation screening up to 3 years post-transplantation were taken into account and divided into costs of patient care and programme-related costs. Mean cost of renal transplantation varied from 70,723 Euros for cadaveric donor transplantations to 76,577 Euros for living donor transplantations. Mean costs of liver transplantation were 141,510 Euros and the mean costs of heart transplantation were 17, 828 Euros. Direct costs of patient care contributed to 79%, 87% and 92% of the costs of renal, liver and heart transplantation respectively. Inpatient hospital days were the largest contributor to the costs of patient care. The mean number of inpatient hospital days from pretransplantation screening to 3 years post-transplantation varied from 46 days for renal transplantation from a living donor to 58 days for renal transplantation from cadaveric donors, 83 days for heart transplantation and 108 days for liver transplantation. In conclusion, costs of liver and heart transplantation were approximately 2.0 and 2.5 times higher than the cost of renal transplantation. Length of inpatient hospital stay for transplantation did not change substantially over time between 1995 and 2001. 相似文献