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1.
J T Johnson R L Wagner D E Schuller J Gluckman J Y Suen N L Snyderman 《Archives of otolaryngology--head & neck surgery》1992,118(5):488-490
The leading cause of postoperative morbidity in patients undergoing major head and neck surgical procedures is postoperative infection. This prospective randomized multi-institutional clinical trial was designed to compare the effectiveness of clindamycin phosphate and high-dose cefazolin sodium therapy in preventing postoperative wound sepsis in patients undergoing contaminated head and neck surgical procedures in which flap reconstruction was required. Either clindamycin phosphate (900 mg) or cefazolin sodium (2 g) therapy was instituted intravenously prior to surgery and continued every 8 hours, for a total of 24 hours. The patients received postoperative follow-up, and the wounds were graded according to the worst condition observed. One hundred cases were evaluated. Fifty-one patients received clindamycin and 49 patients received high doses of cefazolin; wound infection developed in 10 patients (19.6%) and 11 patients (21.6%), respectively. This difference was not statistically significant. The average duration of surgery was approximately 8 hours for both the infected and the noninfected groups of patients. High-dose cefazolin and clindamycin have similar efficacy when administered prophylactically under these circumstances. Reconstruction with free vascularized tissue may aid in reducing postoperative wound infection. 相似文献
2.
E. W. Brien Joseph M. Mirra Steven Kessler M. Suen J. K. S. Ho W. T. Yang 《Skeletal radiology》1997,26(4):246-255
It is not uncommon for sarcomatous transformation of giant cell tumor (GCT) of bone to occur after radiation, but rarely
does malignant transformation occur spontaneously, with less than 15 cases reported up to 1995. Only four of these cases have
been documented in detail. We report two additional cases of GCT of bone spontaneously transforming or ”dedifferentiating”
into osteosarcoma without radiation therapy. The first case is absolutely unique and most interesting in that the dedifferentiation
process occurred in one of multiple GCT lung metastases 6 years after successful eradication of a primary tibial tumor. The
right lung was resected due to development of a large tumor, and at pathologic examination, demonstrated several small nodules
of conventional GCT and a much larger, 14-cm mass composed of a mixture of GCT and high-grade osteosarcoma. The second case
involved a physician, who had a large tumor in the sacrum with vague symptoms for 8 years. Open biopsy revealed conventional,
benign GCT of bone with a secondary aneurysmal bone cyst. Complete curettage 2 weeks later revealed, in addition to areas
of conventional, benign GCT a second component of very high grade osteosarcoma. Both patients died less than 1.5 years from
diagnosis. This report of osteosarcomatous transformation of a conventional GCT of bone strengthens the theory that there
is a mesenchymal cell line in GCT that may spontaneously tansform to sarcoma. 相似文献
3.
DNA错配修复基因甲基化在肝细胞癌发生发展中的作用 总被引:5,自引:1,他引:5
目的探讨DNA错配修复基因(MMR)hMLH1,hMSH2和hMSH3甲基化在肝细胞癌(HCC)发生发展中的作用。方法采用甲基化特异性聚合酶链反应(MSP)法对38例新鲜HCC组织,相应非肿瘤肝组织,2例正常的捐肝组织及6种肝癌细胞系的hMLH1,hMSH2和hMSH3基因启动子CpG岛甲基化进行检测;培养6种肝癌细胞系,MSP法检测加入5-aza-2‘-deoxycytidine前后hMSH2基因在HCC中的甲基化状态改变;逆转录.聚合酶链反应(RT-PCR)方法检测加入5-aza-2’-deoxycytidine前后hMSH2在肝癌细胞株中的mRNA表达改变。结果HCC标本中13.2%(5/38)发生了hMLH1启动子甲基化,68.4%(26/38)发生了hMSH2启动子甲基化;相应的非肿瘤肝组织中hMLH1,hMSH2启动子甲基化阳性率分别为2.6%(1/38),55.3%(21/38);2例正常肝组织中未发现甲基化;6株肝癌细胞系中有5株发生了hMSH2启动子甲基化,而未发现有MLH1启动子甲基化。所有标本中均未发现有hMSH3启动子甲基化。5-aza-2‘-deoxycytidine处理细胞株后,可部分或完全逆转hMSH2启动子甲基化,各细胞株的mRNA均有不同程度的表达增加。结论hMSH3基因启动子CpG岛甲基化与HCC的发生发展关系不大。hMSH2基因甲基化与mRNA表达密切相关,是基因表达调节的一种重要方式。hMLH1和hMSH2基因启动子CpG岛的高甲基化在HCC中是一个常见的基因改变,DNA错配修复基因尤其是hMSH2基因启动子甲基化在HCC的发生中起了重要作用,是早期事件,其可能为临床诊断HCC提供新的检测指标。 相似文献
4.
Two unusual benign lesions of the neck masquerading as malignancy on fine-needle aspiration cytology
Kristy E. Dundas Maria P. Wong Kenneth C. Suen James L. Finley 《Diagnostic cytopathology》1995,12(3):272-278
Two cases of unusual benign tumors of the neck are described, both of which were initially misdiagnosed on cytology as carcinomas. Fine-needle aspiration findings in each case demonstrated a pleomorphic population of cells including bizarre multi-nucleated giant cells, the latter raising the false impression of malignancy. However, on review the cytological appearances of the tumors, a pleomorphic lipoma and a carotid body tumor, were characteristic. the correct diagnosis in each case would have been made or suggested if the pathologist had been familiar with the cytologic features characteristic of the lesion and the differential diagnosis of the head and neck tumors. in addition, the point is made that adequate clinical information is essential for the pathologist if all relevant conditions are not to be missed in the differential diagnosis. 相似文献
5.
The randomized response survey technique appears to be suitable for studies of sensitive sexual behaviors, particularly in AIDS-related research. However, existing methods provide only estimates of group statistics, not of individual information. Additionally, the popular "unrelated question" approach requires the knowledge of the parameters of the unrelated question. In this article, a variation of the unrelated-question method is suggested for use. Specifically, it is suggested that the unrelated question be one to which the response is known to be "yes." Through this "controlled" approach, the raw data become a direct linear transformation of the response to the sensitive question, and thus can be used directly in regression and other analyses at the individual score level. The estimation of the parameters for the unrelated question is not necessary and the hesitation to provide a "yes" response found in the "forced choice" method is minimized. 相似文献
6.
BACKGROUND: The purpose of this article is to define the outcome of intracranial extension of inverted papilloma and outline a rationale for management of this rare clinical presentation. METHODS: A review of patients with intracranial extension of inverted papilloma reported in the literature (18 patients), or treated in our institution (3 patients ) was performed. The data of these 21 patients were consolidated with regard to clinical presentation, treatment, and outcome. Nine patients, including 1 of our cases, had coexisting squamous cell carcinoma and therefore were excluded from the analysis. Twelve patients with "pure" inverted papilloma formed the basis of this study. RESULTS: The majority of patients (83%) with intracranial inverted papilloma had recurrent disease. Patients with extradural disease had a survival rate of 86% with an average follow-up of 4.4 years. Eighty-six percent of these survivors were treated with craniofacial resection. In contrast, 75% of patients with intradural inverted papilloma were dead of disease with an average follow-up of 9.3 months regardless of the treatment modality. CONCLUSIONS: Intracranial extension of inverted papilloma is mostly associated with recurrent disease. Intracranial extradural inverted papilloma can be effectively controlled with craniofacial resection. Intracranial intradural involvement of inverted papilloma has a poor prognosis regardless of treatment. Aggressive treatment of intranasal inverted papilloma may be the most important factor in preventing intracranial presentation. 相似文献
7.
Flávia Giolo De Carvalho Flávia Troncon Rosa Vivian Marques Miguel Suen Ellen Cristini Freitas Gilberto José Padovan Julio Sérgio Marchini 《Nutrition (Burbank, Los Angeles County, Calif.)》2012,28(11-12):1127-1131
ObjectiveThe aim of this study was to assess the nutritional zinc (Zn) status of elite swimmers during different training periods.MethodsA longitudinal paired study was performed at the University of Sao Paulo in eight male swimmers 18 to 25 y old who had been swimming competitively at the state and national levels for at least 5 y. The swimmers were evaluated over a total period of 14 wk: before the basic and specific preparatory period (BSPP-baseline), at the end of the basic and specific preparatory period (post-BSPP), and at the end of the polishing period (PP). Levels of Zn were determined in the plasma, erythrocyte, urine, and saliva by atomic absorption spectrophotometry. Anthropometric measurements and a 3-d food record were also evaluated.ResultsThe median plasma Zn concentration was below the reference value in all training periods (BSPP-baseline 59 μg/dL, post-BSPP 55.9 μg/dL, after PP 58.8 μg/dL, P > 0.05), as were threshold values for erythrocytes (BSPP-baseline 36.5 μg of Zn/g of hemoglobin, post-BSPP 42 μg of Zn/g of hemoglobin, after PP 40.7 μg of Zn/g of hemoglobin, P > 0.05), urinary Zn (BSPP-baseline 280 μg/24 h, post-BSPP 337 μg/24 h, after PP 284 μg/24 h, P > 0.05), and salivary Zn (BSPP-baseline 66.1 μg/L, post-BSPP 54.1 μg/L, after PP 79.7 μg/L, P > 0.05). Salivary Zn did not correlate with plasma and erythrocyte Zn levels.ConclusionThe results suggest that the elite swimmers studied presented a possible Zn deficiency and that salivary Zn was not adequate to evaluate the Zn nutritional status. 相似文献
8.
9.
Krista Beth Highland Audrey Schoomaker Winifred Rojas Josh Suen Ambareen Ahmed Zhiwei Zhang Sarah Fink Carlin Christian E. Calilung Michael Kent Christin McDonough Chester C. Buckenmaier 《Archives of physical medicine and rehabilitation》2018,99(1):91-98
Objective
To examine the feasibility and preliminary effectiveness of an individualized yoga program.Design
Pilot randomized controlled trial.Setting
Military medical center.Participants
Patients (N=68) with chronic low back pain.Interventions
Restorative Exercise and Strength Training for Operational Resilience and Excellence (RESTORE) program (9–12 individual yoga sessions) or treatment as usual (control) for an 8-week period.Main Outcome Measures
The primary outcome was past 24-hour pain (Defense & Veterans Pain Rating Scale 2.0). Secondary outcomes included disability (Roland-Morris Disability Questionnaire) and physical functioning and symptom burden (Patient-Reported Outcomes Measurement Information System-29 subscales). Assessment occurred at baseline, week 4, week 8, 3-month follow-up, and 6-month follow-up. Exploratory outcomes included the proportion of participants in each group reporting clinically meaningful changes at 3- and 6-month follow-ups.Results
Generalized linear mixed models with sequential Bonferroni-adjusted pairwise significance tests and chi-square analyses examined longitudinal outcomes. Secondary outcome significance tests were Bonferroni adjusted for multiple outcomes. The RESTORE group reported improved pain compared with the control group. Secondary outcomes did not retain significance after Bonferroni adjustments for multiple outcomes, although a higher proportion of RESTORE participants reported clinically meaningfully changes in all outcomes at 3-month follow-up and in symptom burden at 6-month follow-up.Conclusions
RESTORE may be a viable nonpharmacological treatment for low back pain with minimal side effects, and research efforts are needed to compare the effectiveness of RESTORE delivery formats (eg, group vs individual) with that of other treatment modalities. 相似文献10.
Celecoxib versus diclofenac plus omeprazole in high-risk arthritis patients: results of a randomized double-blind trial 总被引:8,自引:0,他引:8
Chan FK Hung LC Suen BY Wong VW Hui AJ Wu JC Leung WK Lee YT To KF Chung SC Sung JJ 《Gastroenterology》2004,127(4):1038-1043
BACKGROUND & AIMS: The gastric safety of cyclooxgenase-2 inhibitors and prophylactic antisecretory therapy in high-risk arthritis patients is unclear. We studied the ulcer incidence and factors predicting ulcer recurrence in a prospective, double-blinded trial. METHODS: We studied patients who presented with nonsteroidal anti-inflammatory drug-associated ulcer bleeding. After ulcer healing, patients who were negative for Helicobacter pylori were randomly assigned to celecoxib 200 mg twice a day plus omeprazole placebo once daily or diclofenac 75 mg twice daily plus omeprazole 20 mg once daily for 6 months. Patients underwent endoscopy if they developed recurrent bleeding. Those without recurrent events underwent endoscopy at their last follow-up visit. RESULTS: Two hundred eighty-seven patients were enrolled; 24 had recurrent gastrointestinal complications. Among 259 patients without events, 222 underwent endoscopy (116 received celecoxib and 106 received diclofenac plus omeprazole). The probability of recurrent ulcers in 6 months was 18.7% in the celecoxib group and 25.6% in the diclofenac plus omeprazole group (difference, -6.7%; 95% CI: -17.8% to 3.9%) (P = 0.21). Combining bleeding and endoscopic ulcers, 24.1% in the celecoxib group and 32.3% in the diclofenac plus omeprazole group had recurrent ulcers in 6 months (difference, -8.2%; 95% CI: -19.5% to 2.9%) (P = 0.15). Treatment-induced significant dyspepsia (hazard ratio, 5.3; 95% CI: 2.6-10.8), age > or =75 (hazard ratio, 2.0; 95% CI: 1.1-3.5), and comorbidity (hazard ratio, 2.1; 95% CI: 1.2-3.7) independently predicted ulcer recurrence. CONCLUSIONS: Among patients with previous ulcer bleeding, neither celecoxib nor diclofenac plus omeprazole adequately prevents ulcer recurrence. Treatment-induced significant dyspepsia is an indication for endoscopic evaluation. 相似文献