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51.
Hepatotoxicity of antituberculosis drugs.   总被引:1,自引:0,他引:1       下载免费PDF全文
L. P. Ormerod  C. Skinner    J. Wales 《Thorax》1996,51(2):111-113
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52.
Background. Although it has been established that basal cell carcinoma is an uncommon diagnosis in black patients, the morpheaform subtype is very rare among these individuals.
Objective. The objective is to present two cases of morpheaform basal cell carcinoma in African-American patients.
Methods. This is a case series and a literature review using the Ovid Medline Database. Key words used in the search include "basal cell carcinoma,""African American,""black,""African,""negros,""morpheaform,""sclerosing,""fibrosing," and "scar-like basal cell carcinoma." The Ovid Medline Database was searched from 1966 to present and was restricted to the English language.
Results. A review of the Emory Dermatology clinic charts from 1989 to 2004 revealed two black patients with morpheaform basal cell carcinomas.
Conclusions. Although extremely rare, morpheaform pattern basal cell carcinoma must be considered in the differential diagnosis for black patients presenting with nonhealing lesions.  相似文献   
53.
A previously developed eigenvector formalism is adapted to off-resonance in the transient response of quasiperiodic steady-state free precession (SSFP) sequences, including TrueFISP as a special case. The effective relaxation rates for essentially parallel and perpendicular deviations from the steady state are determined analytically in leading order perturbation theory. The latter are a known cause of oscillatory artifacts and therefore constitute the main target of a variety of preparation techniques. In addition, the former also play a dominating role in applications such as inversion recovery (IR) TrueFISP, which intentionally measure far away from the equilibrium. For both components, the approach toward equilibrium turns out to depend sensitively on field inhomogeneities, especially for smaller ratios of T2/T1. For the perpendicular deviations, the calculations show that--except very close to banding artifacts, where the steady-state signal is almost zero--field inhomogeneities additionally increase their effective relaxation rate almost as much as in the free induction decay (FID). The analytical results are tested against numerical simulation and MR measurements.  相似文献   
54.
Spoiled gradient echo sequences can only reach a homogeneous steady state if sufficiently strong crusher gradients are used in combination with RF phase cycling (RF spoiling). However, the signal depends quite sensitively on the chosen phase increment ? and—lacking analytical solutions—numerical simulations must be used to study the transient and steady‐state magnetization. For the steady state an exact analytical solution is derived, which holds for arbitrary sequence and tissue parameters. Besides a considerably improved computation performance, the analytical approach enables a better understanding of the complicated dependence on ?. For short repetition times (TR) the regime of small ? turns out to be particularly interesting: It is shown that the typical ?c, where RF spoiling starts to become effective, is essentially inversely proportional to T2. This tissue dependence implies that contrasts can be considerably larger with partial spoiling (? ≈ ?c) than with conventional RF spoiling (? ? ?c). As an example, the uptake of contrast agents in tissues is investigated. For typical parameters a considerably improved contrast enhancement can be obtained, both theoretically and experimentally. Magn Reson Med, 2006. © 2005 Wiley‐Liss, Inc.  相似文献   
55.
Proximal radioulnar transposition in an elbow dislocation is rare. Only three cases have been recorded. Translocation can easily be missed unless radiographs are carefully examined. Proximal radioulnar translocation has been believed to be iatrogenic. The injury we report was not iatrogenic, and mechanical locking of radial head and neck fracture necessitated open reduction.  相似文献   
56.
Management of adult sarcomas of the bladder and prostate   总被引:7,自引:0,他引:7  
Historically, survival of patients with adult pelvic sarcoma of the bladder and prostate has been poor. Between November 1974 and November 1984 we treated 11 patients with leiomyosarcoma: 7 with primary bladder and 4 with prostate tumors. Patients with nonbulky disease underwent surgical resection and were observed if the margins and nodes were negative. Patients with positive surgical margins or nodes were treated adjunctively with external beam radiotherapy, 4,500 to 5,000 rad, and chemotherapy. Patients with bulky disease were treated with preoperative chemotherapy with or without radiotherapy followed by an exenterative operation. Of the 11 patients 9 are without evidence of disease with a mean followup of 61 months (range 35 to 96 months). One patient was lost to followup after 4 months and 1 died of disease after 11 months. Three patients with rhabdomyosarcoma were treated and 1 had no evidence of disease 24 months after therapy. Two patients died at 4 and 18 months.  相似文献   
57.
The tumorigenicity of neoplastic hamster and mouse cell lines and tumour explants was reduced by infection with herpes simplex virus (HSV-1), a thymidine-kinaseless mutant of herpes simplex virus, namely 'MDK', encephalomyocarditis virus (EMC) and bovine mammillitis virus (BMV). There was an approximate relationship between duration of virus infection in vitro and reduction in incidence and/or rate of tumour development. The rate of tumour development was also reduced by 'site inoculation' of virus (HSV-1) at various time intervals following inoculation of tumorigenic BHK 21 cells indicating that virus was capable of reducing the rate of tumour development in a situation where the neoplastic cells were already transplanted into the susceptible host species. It is suggested that the therapeutic role of wild type, mutant or recombinant viruses merits further exploration towards prevention and treatment of human cancer.  相似文献   
58.
When complex prostheses are fabricated, it is expected that at some point maintenance will be necessary. This clinical report documents a 10-year-old maxillary spark erosion prosthesis that had been repaired many times, was discolored, and exhibited significant signs of wear. The metal superstructure was intact; therefore, only the acrylic resin base and teeth needed to be replaced. To reduce both cost and time without the prosthesis for the patient, the rehabilitation was completed within 24 hours.  相似文献   
59.
The Childrens Cancer Study Group evaluated daily oral 13-cis-retinoic acid to determine its therapeutic efficacy in 28 children with advanced neuroblastoma refractory to conventional therapy. Cheilitis and fissured lips were the most common side effects; however, fewer than 50% of the patients experienced any toxicity. Two of twenty-two evaluable children demonstrated positive response to therapy. In one case, a child received the drug for 11 months. Seventeen patients demonstrated progressive disease within 28 days of the start of treatment. Three other patients with stable disease, or removed from study at day 28, were considered nonresponsive. Our data demonstrate that, when given as a single daily oral dose of 100 mg/m2, 13-cis-retinoic acid does not have significant activity in children with advanced neuroblastoma. © 1992 Wiley-Liss, Inc.  相似文献   
60.
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