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31.
Winnepenninckx B Errijgers V Hayez-Delatte F Reyniers E Frank Kooy R 《Human mutation》2002,20(4):249-252
Mutations in the methyl-CpG-binding protein 2 (MECP2) cause Rett syndrome, a severe neurodevelopmental disorder occurring predominantly in females. Male patients with Rett syndrome are extremely rare, as the Rett-causing mutations in the MECP2 gene are usually lethal in hemizygous males. However, different mutations in the same gene were reported to cause mental retardation, both in sporadic non-syndromic males as well as in syndromic families with disease manifestation in carrier females. The majority of the reported MECP2 mutations in mentally retarded patients cause amino acid substitutions and, especially in isolated cases, discrimination between a disease-causing mutation and a rare polymorphism is not obvious and the significance of each individual variation should be verified. We mapped a new non-syndromic X-linked family (MRX79) to the chromosomal region Xq27.3-Xq28 and identified an A140V mutation in the MEPC2 gene in all patients with the disease haplotype. In addition to data published by others, this suggests that A140V is a recurrent mutation (and not a polymorphism) found in patients with X-linked mental retardation. 相似文献
32.
A functional hippocampus is required for trace fear conditioning, which involves learning the association of a tone and shock that are separated over time. Young and aged rats received 10 trace conditioning trials. Twenty-four hours later, rats were tested for fear to the tone in a novel chamber by measuring freezing. The results showed significantly lower levels of freezing in aged rats as compared with young rats, which provides evidence of age-related memory impairments. Pseudorandom conditioning groups showed low levels of freezing, indicative of no associative memory. Age-related memory deficits were not found with delay conditioning, which suggests no age-related sensory-motor deficits. These data suggest that aging hinders the ability of the hippocampus to process information separated over time. 相似文献
33.
Bernard Fisher Edwin R. Fisher Carol Redmond Ann Brown Contributing NSABP Investigators 《Breast cancer research and treatment》1986,7(3):147-160
Summary Previous reports by us have shown that the outcome of breast cancer patients who have received systemic adjuvant therapy is influenced by tumor estrogen or progesterone receptor (ER or PR) content or by nuclear grade. This publication provides information regarding the relative merit of those three markers. Findings from patients receiving L-PAM plus 5-FU (PF) or PF plus tamoxifen (PFT) indicate that the disease-free survival and survival within each regimen was almost identical when related to either ER, PR, or nuclear grade. Those having tumors with either of the receptors 10 fmol or a good nuclear grade had a better outcome through five postoperative years than did those with ER or PR 0–9 fmol or poor nuclear grade. The magnitude of the difference was similar for each of the three discriminants. Since they were found to be of equal predictive value, one marker might well serve as a substitute for another. Cox regression analyses, however, clearly indicate that ER, PR, and nuclear grade have an independent influence on outcome and that a more accurate assessment of outcome is obtained when more than one marker is employed. Thus, information should be obtained on as many markers as possible. This conclusion is supported by observations presented which indicate that nuclear grade in combination with either or both of the receptors is a better predictor than either marker alone and that, as indicated by life table probability values and relative odds ratios, an increasing number of favorable tumor prognostic indicators results in a better patient outcome particularly in PFT-treated patients. A possible explanation is considered for why the separation of receptor/nuclear grade categories is more orderly and pronounced in PF-treated patients receiving tamoxifen than in those given PF alone.
See Appendix I 相似文献
34.
Chun Pong Daniel Kwok Siu Yan Bess Tsui Kin Wai Edwin Chan 《Journal of pediatric surgery》2021,56(7):1145-1149
Objective: Through historical comparison with our previous study published 10 years ago, this paper aims to provide latest analysis of local bacteriology of acute complicated appendicitis and evaluate the effects of early escalation of potent antibiotics on course of postoperative recovery.Methods: A 5-year retrospective review of all children receiving emergency laparoscopic appendicectomies for acute appendicitis from December 2014 to November 2019 was conducted.Results: 257 cases of acute appendicitis were included, 126 were complicated appendicitis (38 gangrenous, 88 ruptured). 96 had positive peritoneal swab culture, 53 (42.1%) grew resistant bacterial strains, including extended spectrum beta-lactamase producing E. coli (ESBL E. coli), Pseudomonas aeruginosa, against traditional empirical triple antibiotics. The prevalence had significantly increased over the past decade (p = 0.008). In our patients, piperacillin/tazobactam, ertapenem, gentamicin provided coverage of 69.8%, 45.3% and 45.3% respectively. For patients with early escalation of postoperative antibiotics, no statistical significance was identified in terms of postoperative complications (p = 0.883), or duration of antibiotics (p = 0.0615).Conclusion: Growing prevalence of resistant strains were observed over the decade. Piperacillin/tazobactam provided the best coverage (69.8%) against resistant bacterial strains in our patients. Early escalation of antibiotics failed to reduce postoperative complications and antibiotics duration.Type of Study: Clinical Research, Retrospective Historical Comparative StudyLevel of Evidence: Level III 相似文献
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37.
Grannum R. Sant M.D. Angelo A. Ucci Jr. M.D. PH.D. Edwin M. Meares Jr. M.D. 《Urology》1983,21(6):632-634
A renal tumor developing in a patient receiving cyclophosphamide (Cytoxan) therapy for Wegener granulomatosis is reported. The tumor was similar histologically to the "immunoblastic" sarcoma that develops in renal allograft recipients as a complication of immunosuppressive therapy. This case report strengthens the cause and effect relationship between immunosuppressive drug usage and the subsequent development of neoplasia. 相似文献
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39.
Anthony T C Chan Brigette B Y Ma Y M Dennis Lo S F Leung W H Kwan Edwin P Hui Tony S K Mok Michael Kam Lisa S Chan Samuel K W Chiu K H Yu K Y Cheung Karen Lai Maria Lai Frankie Mo Winnie Yeo Ann King Philip J Johnson Peter M L Teo Benny Zee 《Journal of clinical oncology》2004,22(15):3053-3060
PURPOSE: To assess the efficacy of neoadjuvant paclitaxel and carboplatin (TC) followed by concurrent cisplatin and radiotherapy (RT) in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) and to monitor treatment response with plasma Epstein-Barr virus (EBV) DNA. PATIENTS AND METHODS: Thirty-one patients with International Union Against Cancer stages III and IV undifferentiated NPC had two cycles of paclitaxel (70 mg/m2 on days 1, 8, and 15) and carboplatin (area under the curve 6 mg/mL/min on day 1) on a 3-weekly cycle, followed by 6 to 8 weeks of cisplatin (40 mg/m2 weekly) and RT at 66 Gy in 2-Gy fractions. Plasma EBV DNA was measured serially using the real-time quantitative polymerase chain reaction method. Results All patients completed planned treatment. Response to neoadjuvant TC was as follows: 12 patients (39%) achieved partial response (PR) and 18 achieved (58%) complete response (CR) in regional nodes; five patients (16%) achieved PR and no patients achieved CR in nasopharynx. At 6 weeks after RT, one patient (3%) achieved PR and 30 patients (97%) achieved CR in regional nodes, and 31 patients (100%) achieved CR in nasopharynx; 29 patients (93%) had EBV DNA level of less than 500 copies/mL. Neoadjuvant TC was well tolerated, and the most common acute toxicity of cisplatin plus RT was grade 3 mucositis (55%). At median follow-up of 33.7 months (range, 7 to 39.3 months), six distant and three locoregional failures occurred. Plasma EBV DNA level increased significantly in eight of nine patients who experienced treatment failure but did not increase in those who did not. The 2-year overall and progression-free survival rates were 91.8% and 78.5%, respectively. CONCLUSION This strategy was feasible and resulted in excellent local tumor control. Serial plasma EBV DNA provides a noninvasive method of monitoring response in NPC. 相似文献
40.
Bradley R Pieters Augustinus A M Hart Nicola S Russell Edwin P M Jansen Johannes L Peterse Jacques Borger Emiel J Th Rutgers 《Radiotherapy and oncology》2003,67(2):159-164
BACKGROUND AND PURPOSE: Interstitial implants for brachytherapy boost in the breast conserving therapy of breast cancer can be performed in two ways; implants during the tumor excision (per-operative implants) or after the external beam therapy (delayed interstitial implants). Differences in cosmetic outcome were investigated. PATIENTS AND METHODS: Cosmetic results in 47 patients having a per-operative implant were compared to 123 patients having a delayed interstitial implant in a matched case-control study. Cosmesis was scored on a four-point-scale varying from 0 (excellent) to 3 (poor). RESULTS: After mean follow-up of 63 months, three observers found no difference in cosmetic outcome between the two groups after adjustment for variables found to be related with cosmesis (difference in mean score 0.50, P=0.26). Implant volume at 100% isodose was not found to differ (P=0.084) between the per-operative group (mean 102 cm3, S.D. 34 cm3) and the delayed group (mean 93 cm3, S.D. 29 cm3). CONCLUSIONS: Performing per-operative implants has not led to smaller implants. The method of performing brachytherapy does not result in marked differences in cosmetic outcome. 相似文献