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81.
C Badenas J To-Figueras JD Phillips CA Warby C Muñoz and C Herrero 《Clinical genetics》2009,75(4):346-353
Porphyria cutanea tarda (PCT) arises from decreased hepatic activity of uroporphyrinogen decarboxylase (UROD). Both genetic and environmental factors interplay in the precipitation of clinically overt PCT, but these factors may vary between different geographic areas. Decreased activity of UROD in erythrocytes was used to identify patients with UROD mutations among a group of 130 Spanish PCT patients. Nineteen patients (14.6%) were found to harbor a mutation in the UROD gene. Eight mutations were novel: M1I, 5del10, A22V, D79N, F84I, Q116X, T141I and Y182C. Five others were previously described: F46L, V134Q, R142Q, P150L and E218G. The new missense mutations and P150L were expressed in Escherichia coli. D79N and P150L resulted in proteins that were localized to inclusion bodies. The other mutations produced recombinant proteins that were purified and showed reduced activity (range: 2.3–73.2% of wild type). These single amino acid changes were predicted to produce complex structural alterations and/or reduced stability of the enzyme. Screening of relatives of the probands showed that 37.5% of mutation carriers demonstrated increased urinary porphyrins. This study emphasizes the role of UROD mutations as a strong risk factor for PCT even in areas where environmental factors (hepatitis C virus) have been shown to be highly associated with the disease. 相似文献
82.
The effectiveness of beta-carotene (betaC) as a vitamin A (VA) precursor may be influenced by the proportions of cis isomers of betaC consumed in the diet. Although the metabolic fates of cis isomers of betaC are poorly understood, their retinol equivalency has been assigned a value 50% that of all-trans (at) betaC. A dose-response design was used to estimate the relative VA value (VAV) of atbetaC, 9-cis (9c) betaC and 13-cis (13c) betaC in gerbils using total liver retinol as a measure of VAV. Ten groups of gerbils received a daily dose of oil with or without betaC isomer by gavage for 7 d. Nine groups (n = 5) were divided equally among the three betaC dosing treatments with each isomer provided at 141, 275 and 418 nmol/d. Total liver VA (171-259 nmol) in gerbils administered atbetaC was higher than total liver betaC (25-53 nmol). Stores of VA and betaC in livers from gerbils administered atbetaC were higher than stores of VA and betaC in livers from those given 9cbetaC or 13cbetaC. The relative VAV of cis betaC isomers was estimated by comparing slopes of dose-response lines of all three betaC isomers using atbetaC as a reference. Total liver VA and betaC increased linearly (P < 0.05) with increasing betaC intake in gerbils gavaged with all three betaC isomer oils. The relative VAV of 9cbetaC was less (38%) and 13cbetaC was more (62%) than the assigned value of 50% that of atbetaC. Thus, the proportions of cis isomers of betaC contained in a food could negatively affect the vitamin A value of the diet. 相似文献
83.
Euhus DM Peters GN Leitch AM Saboorian H Mathews D Erdman W Anglin B Huth J 《Journal of surgical oncology》2002,79(4):209-215
BACKGROUND AND OBJECTIVES: The mammary sentinel lymph node (SLN) procedure has the potential to improve the accuracy and lower the morbidity of axillary staging in breast cancer patients, but results are closely linked to experience and can vary widely between institutions. Standardized performance measures need to be established in order to optimize the transition to SLN biopsy only. METHODS: Performance data were prospectively collected for the first 156 mammary SLN procedures performed by three surgeons in our institution. RESULTS: Seventy-five cases were required to achieve an SLN visualization rate of > 80% on preoperative lymphoscintigraphy. The SLN visualization rate was 90% for the last 52 cases. Two surgeons required 25 cases before consistently achieving a > or = 90% SLN identification rate in the operating room and one required 15 cases. The metastasis detection rate increased from 22% for the first 52 cases to 31% for the last 52 cases. The false negative rate for the procedure was 5%. CONCLUSIONS: The following performance criteria and benchmarks are suggested for validating the performance of the SLN team: (1) SLN visualization rate on preoperative lymphoscintigraphy > or = 80%, (2) SLN identification rate in the operating room > or = 90%, (3) False negative rate for the procedure 5%. Thirty procedures per surgeon were sufficient to achieve these benchmarks in our group. 相似文献
84.
目的 对比分析下肢骨肉瘤的X线与MRI表现,探讨MRI对骨肉瘤的诊断价值。方法 收集经手术或病理穿刺活检证实的下肢骨肉瘤15例,男11例,女4例,均行MRI平扫及增强扫描(4例行CT扫描),并摄有X线平片,对其MRI征象与X线征象作逐一对比。结果 MRI及X线平片对下肢骨肉瘤的诊断准确率均为100%,MRI在显示病变范围、放射状骨针、Codman三角两层结构以及跳跃病灶等方面明显优于X线平片检查。结论 X线平片是诊断骨肉瘤最简便而实用的方法,但MRI可以更好的显示病变的范围,发现早期病变。 相似文献
85.
Saadat P. Cesnorek S. Ram R. 《世界核心医学期刊文摘》2006,2(8):47-48
神经节细胞瘤是一种神经内分泌肿瘤,其发生与自主神经系统的交感或副交感神经节有关。罕见发生于膀胱、前列腺和子宫。本文作者报道1例发生于儿童头皮的原发性皮肤神经节细胞瘤。对此肿瘤进行了组织学、免疫组化和超微结构研究。该病例可能代表神经嵴细胞向鳃弓发育过程中的一种异常迁移。此外,研究结果还强调在胚胎发育过程中神经嵴和鳃弓/裂之间有复杂的相互作用。 相似文献
86.
Lymphatic mapping and sentinel node identification in patients with cervix cancer undergoing radical hysterectomy and pelvic lymphadenectomy. 总被引:37,自引:0,他引:37
Charles Levenback Robert L Coleman Thomas W Burke W Michael Lin William Erdman Michael Deavers Ebrahim S Delpassand 《Journal of clinical oncology》2002,20(3):688-693
PURPOSE: The purpose of this study was to determine the feasibility of sentinel node identification in patients with invasive cervix cancer undergoing radical hysterectomy and pelvic lymphadenectomy using preoperative and intraoperative lymphatic mapping. PATIENTS AND METHODS: Thirty-nine patients at two institutions were enrolled onto this institutional review board-approved study. All underwent preoperative lymphoscintigraphy and intraoperative lymphatic mapping with blue dye and a handheld gamma probe. Radical hysterectomy was aborted in four patients because metastatic disease was discovered on frozen section analysis of the sentinel node. RESULTS: Preoperative lymphoscintigraphy revealed at least one sentinel node in 33 patients (85%), including 21 (55%) with bilateral sentinel nodes. All 39 patients had at least one sentinel node identified intraoperatively. Eighty percent of sentinel nodes were in three pelvic locations: iliac, obturator, and parametrial (in descending order of frequency). The remaining sentinel nodes were in the common iliac and para-aortic nodal basins. A total of 132 nodes were identified clinically as sentinel nodes; 65 (49%) were both blue and hot, 35 (27%) were blue only, and 32 (24%) were hot only. Eight patients (21%) had metastatic disease. In five of these patients, sentinel nodes were the only positive lymph nodes. One patient had false-negative sentinel nodes. She had four microscopically positive parametrial nodes that were resected in continuity with the uterus. The sensitivity of the sentinel node was 87.5% and the negative predictive value was 97%. CONCLUSION: Preoperative lymphoscintigraphy and intraoperative lymphatic mapping were highly successful at identifying sentinel nodes in patients undergoing radical hysterectomy. 相似文献
87.
van Domburg RT Scmidt Pedersen S van den Brand MJ Erdman RA 《Journal of psychosomatic research》2001,51(3):469-477
OBJECTIVE: To examine the independent prognostic value of the four subscales of the Heart Patients Psychological Questionnaire (HPPQ) on mortality in male and female patients 10 years following percutaneous transluminal coronary angioplasty (PTCA). METHODS: The HPPQ, which measures well-being, feelings of being disabled, despondency, and social inhibition, was administered to 356 patients (23% women) post-PTCA. The patients were followed for a median of 10 years. Clinical and demographic variables were sampled from medical records. RESULTS: During the follow-up period, 104 patients (29%) had died. Women scored significantly worse on all psychological subscales compared with men. Fifty-nine (72%) women and 92 (34%) men had a score indicating at least mild to moderate feelings of being disabled. Men scoring high on feelings of being disabled were at increased risk of mortality compared with men having a low score, adjusted for other cardiac risk factors (chi(2)=7; P=.008). No differences were found between women with low or high scores on feelings of being disabled (relative risk (RR): 1.2; 95% confidence interval (CI): 0.5-3.3). None of the other HPPQ subscales were related to mortality. CONCLUSION: Feelings of being disabled measured at least 1 year after hospital discharge is a significant predictor of mortality in men 10 years post-PTCA, but not in women. This finding adds to the increasing knowledge that psychosocial variables influence morbidity and mortality in cardiac patients. 相似文献
88.
89.
90.
一例AML中一种新的TCRδ基因重排及其分析方法 总被引:5,自引:0,他引:5
T细胞抗原受体(TCR)功能的表达有赖于该基因在正常T淋巴细胞发育过程中的重排。近年来,已发现一些肿瘤及白血病中出现该基因的异常重排。我们采用聚合链反应(PCR)、“磁珠”固相纯化方法和PCR产物直接测序等方法,从一例AML中发现了一种在白血病中未报道过的TCRδ基因重排,该重排是一种新报道的Dδ区DδX片段的重排,为DδXDδDδJδ不完全重排。在研究白血病TCR基因重排中,采用本文所报道的方法 相似文献