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1.
A 37-year-old woman receiving long-term hemodialysis was admitted to the hospital with a fever of unknown origin (6 weeks of unexplained, persistent, low-grade fever). Although she had received vancomycin hydrochloride 5 days before the onset of fever, the drug was not suspected as the cause because of the duration of fever, the administration of vancomycin on prior occasions without incident, and the lack of allergic stigmata. After hospitalization, vancomycin and gentamicin sulfate were administered empirically. Immediately thereafter, her temperature rose to 40 degrees C, and over the ensuing 24 hours, eosinophilia and a maculopapular rash developed that resolved entirely when antibiotic therapy was stopped and low-dose steroid therapy was instituted. The prolonged hypersensitivity reaction after a single dose of vancomycin is consistent with the greatly extended half-life of this drug in the population with end-stage renal disease and should alert physicians to the possibility of such persistent idiosyncratic reactions in this group.  相似文献   
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Intraocular lenses containing an ultraviolet chromophore, representing the products of seven manufacturers, were analyzed for chemical and ultraviolet transmission characteristics and the results are reported. The clinical use of this type of intraocular lens and the absence of any long-term safety data are discussed.  相似文献   
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The established treatment for ureterointestinal anastomotic strictures is open surgical revision. In an effort to evaluate the efficacy of endourological surgery for this problem, we compared 7 patients (9 strictures) who underwent open revision to 6 patients (7 strictures) who underwent endoscopic incision and balloon dilation of the stricture. The success rate (that is patent ureter and no stent) was 89 per cent for the open revision group and 71 per cent (5 of 7) for the endoscopic group. All open revisions required use of general anesthesia, while 3 of the endoscopic procedures were performed with the patient under assisted local anesthesia. The endoscopic group had markedly shorter hospitalization, decreased blood loss, diminished patient discomfort and no postoperative complications. While the endoscopic procedure for ureteroileal anastomotic strictures is less successful than open revision, the lower morbidity, decreased cost and shorter hospital stay associated with the endourological approach favor its use over open revision. For elderly patients who fail initial endoscopic revision and for patients with metastatic transitional cell cancer, placement of an indwelling stent is a reasonable alternative. Given these guidelines, less than 30 per cent of the patients who suffer a ureteroileal anastomotic stricture will require open surgical revision.  相似文献   
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Laparoscopic surgery is gaining popularity among the surgical community. While its prevalence expands, the need for reliable training and assessment tools is becoming increasingly important. Laparoscopic skills are not an innate behavior, nor can they be easily mimicked, and can only be acquired through hands-on training. A consensus exists among physicians that establishment and evaluation of technical skill in surgical training programs are inadequate and in need of improvement. A validated, reliable bench model that could train and assess could be standardized and provide numerous benefits including determination of which medical students should consider a career in surgery, valuable feedback to residents, a tracking mechanism of resident performance, a possible certification and recertification tool, and to allow for interinstitutional comparison. To this end, several potentially successful bench models testing dexterity, hand-eye coordination, and depth perception have been developed. A few models have been proven to be both valid and reliable indicators of technical skill. Although the future remains uncertain, enough groundwork has been laid to begin incorporating technical skill training and assessment into surgical training programs.  相似文献   
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We studied 11 head and neck squamous carcinoma (HNSC) cell lines and 46 primary tumors for p16 gene status by protein, mRNA, and DNA genetic/epigenetic analyses to determine the incidence, the mechanism(s), and the potential biological significance of its inactivation. Of the 11 cell lines, only 1 showed intact p16 and 10 lacked its protein and mRNA; DNA analysis of these 10 cell lines showed 2 homozygous deletions, 6 methylations at exon 1 and 2, and 2 with no detectable abnormalities. In primary tumors, 16 (34.7%) of the 46 showed detectable p16 protein and mRNA; of these, 12 had no DNA abnormalities and 4 had only exon 2 methylation. Loss of p16 expression was found in three tumors with concurrent mutation at exon 2 and methylation at exon 2 (two) and both 1 and 2 (one). Of the 30 tumors that lacked p16 protein, 27 also lacked mRNA, 1 had detectable p16 mRNA, and 2 failed RT-PCR amplification. Twenty-two of the thirty tumors showed DNA alterations and eight manifested no abnormalities; DNA alterations comprised 6 homozygous deletions, 2 concurrent mutations and methylation of exon 2, and 13 with methylation at exon 1 and exons 1 and 2 (12 with methylation only and 1 with mutation) at exon 1. Except for patients' gender (P = 0.02), no significant correlation between p16 and clinicopathological factors was observed. We conclude that in HNSC 1) intragenic p16 alterations are infrequent events, 2) methylation of exon 1 constitutes a common mechanism in silencing the p16 gene, 3) p16 inactivation may play an important role in the early development and progression of HNSC, and 4) no association between p16 alterations and conventional clinicopathological factors was noted in this cohort.  相似文献   
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乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。  相似文献   
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BACKGROUND: Surgeons have been using selective neck dissections in the treatment of squamous carcinoma of the upper aerodigestive tract for over 20 years. To date, no data is available that can answer the question "What are the patterns of failure in the neck following a selective neck dissection and is a selective neck dissection a reliable procedure for metastatic disease?" METHODS: To answer this question, the medical records of all patients with squamous carcinoma of the oral cavity, oropharynx, larynx, and hypopharynx treated at The University of Texas M. D. Anderson Cancer Center from January 1, 1985-December 31, 1990, with a selective neck dissection were reviewed. Five hundred seventeen neck dissections were analyzed: suprahyoid (41), supraomohyoid (284), and anterolateral (192). The end point of the study was regional failure and survival. RESULTS: Regional recurrence in patients treated with a suprahyoid dissection was 43% with pathologically positive nodes. The regional recurrence in the patients treated with a supraomohyoid neck dissection was 1.9% with pathologically negative nodes, 35.7% with path N1 without postoperative radiation therapy, and 5.6% with postoperative radiation therapy. The neck staged pathologically N2B failed with and without postoperative radiation, 8.3% and 14%, respectively. Thirteen percent of the anterior/lateral neck dissections failed regionally. If multiple pathologically positive nodes (N2B) were present, the regional failure with postoperative radiation was 30% and 33.3% without postoperative radiation. CONCLUSION: The results of this retrospective study suggest that a selective neck dissection is a satisfactory staging procedure and is a definitive operation if all the nodes are pathologically negative. However, if a node is found to be invaded with cancer, the use of postoperative radiation is advisable.  相似文献   
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