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951.
AC Bateman DA Sage RK Al-Talib JM Theaker DB Jones WM Howell 《Canadian Metallurgical Quarterly》1996,28(2):169-174
Topical application of 5-aminolevulinic acid (5-ALA), with subsequent synthesis of protoporphyrin IX (PPIX), is a novel outstanding procedure for photodynamic treatment. So far, clinical experience has been reported with creams containing 5-ALA for the therapy of skin cancer, oral application for the treatment of gastrointestinal disease and intravesical instillation of 5-ALA solutions for fluorescence detection of superficial bladder cancer. Inhalation of 5-ALA for the staining of bronchial malignancies is a preferred method in clinical pulmonology. Since no adverse reaction was observed in lung function in a canine following inhalation of 5-ALA in increasing concentrations, clinical applications were performed. Seven patients with positive or suspicious sputum cytology, but negative white light bronchoscopy, received 5-10 wt.% 5-ALA in NaCl solution by means of a medical nebulizer. No side effects were observed during and after 5-ALA inhalation. After a period of 3 h, patients underwent fluorescence bronchoscopy using violet light for fluorescence excitation and an optical multichannel analyzer for fluorescence detection in situ. The results showed fluorescence spectra which could be related to PPIX induced by 5-ALA in the bronchial mucosa. The fluorescence intensity was sufficiently high for video imaging using a target integrating color CCD camera adapted to the flexible bronchoscope. Carcinoma in situ, as well as dysplasias, showed a clear positive fluorescence. A correlation of fluorescence contrast with histology on 30 biopsies revealed a high sensitivity, but a specificity below 50%. Improvements in light and drug dosimetry will form the basis for further clinical trials. 相似文献
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953.
BACKGROUND: The optimal method for removal of chest tubes has not been determined and opinion remains divided. The purpose of this study was to determine the difference between two algorithms for the removal of chest tubes: one with continuous negative intrathoracic pressure (suction group) and the other with a trial of water seal (water-seal group). STUDY DESIGN: This study was a prospective randomized trial of 80 trauma patients requiring tube thoracostomies. RESULTS: Both methods of chest tube removal had similar incidences of recurrent pneumothorax (2.5 percent). The suction group had a shorter total chest tube time (72.2 hours versus 92.5 hours, p = 0.013) and shorter time required to remove the chest tube following air leak resolution (25.2 hours versus 35.6 hours, p = 0.034). Additionally, there were more patients requiring prolonged (greater than 36 hours) removal times in the water-seal group (p = 0.009). CONCLUSIONS: Both suction and water-seal methods for chest tube removal are effective and have similar incidences of recurrent pneumothorax. The use of the suction algorithm significantly decreased both chest tube duration and the time taken for chest tube removal. In patients hospitalized for isolated pneumo- or hemothorax, the use of the suction algorithm potentially could lead to shorter length of stay. 相似文献
954.
955.
K Kieburtz D Simpson C Yiannoutsos MB Max CD Hall RJ Ellis CM Marra R McKendall E Singer GJ Dal Pan DB Clifford T Tucker B Cohen 《Canadian Metallurgical Quarterly》1998,51(6):1682-1688
BACKGROUND: Painful sensory neuropathy is a common complication of HIV infection. Based on prior uncontrolled observations, we hypothesized that amitriptyline or mexiletine would improve the pain symptoms. METHOD: A randomized, double-blind, 10-week trial of 145 patients assigned equally to amitriptyline, mexiletine, or matching placebo. The primary outcome measure was the change in pain intensity between baseline and the final visit. RESULTS: The improvement in amitriptyline group (0.31+/-0.31 units [mean+/-SD]) and mexiletine group (0.23+/-0.41) was not significantly different from placebo (0.20+/-0.30). Both interventions were generally well tolerated. CONCLUSIONS: Neither amitriptyline nor mexiletine provide significant pain relief in patients with HIV-associated painful sensory neuropathy. 相似文献
956.
957.
GA Carpinito WM Stadler JV Briggman GW Chodak PA Church DL Lamm PH Lange EM Messing RM Pasciak GB Reservitz RN Ross DB Rukstalis MF Sarosdy MS Soloway RP Thiel N Vogelzang CL Hayden 《Canadian Metallurgical Quarterly》1996,156(4):1280-1285
PURPOSE: The purpose of this trial was to evaluate an immunoassay for urinary nuclear matrix protein, NMP22, as an indicator for transitional cell carcinoma of the urinary tract. MATERIALS AND METHODS: Three groups of subjects participated in this trial of NMP22: 1-175 with transitional cell carcinoma, 2-117 with benign urinary tract conditions and 3-375 healthy volunteers. Each subject provided a single (3 voids) urine sample for analysis at the time of study entry. Each sample was assayed for the level of NMP22. RESULTS: In normal healthy volunteers and in subjects with benign conditions median NMP22 levels were 2.9 and 3.3 units per ml., respectively. Median urinary NMP22 levels in patients with transitional cell carcinoma were significantly greater than in comparison subjects. Patients with active transitional cell carcinoma had significantly greater median urinary NMP22 levels than those with no evidence of disease (6.04 versus 4.11 units per ml., p = 0.027, 1-tailed Mann-Whitney U test). We noted no effect of tumor grade, extent of disease or exposure to intravesical therapy on urinary NMP22 levels. CONCLUSIONS: NMP22 is a promising urinary tumor marker for monitoring transitional cell carcinoma. Nuclear matrix proteins are a new class of tumor markers that represent the basis for the development of assays with increased efficacy for the detection and treatment of cancer. 相似文献
958.
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960.
MF Levin DB Bach AD Vellet PL Munk DB Downey WG Reitz 《Canadian Metallurgical Quarterly》1993,44(3):168-175
The third variable region (V3) of the HIV-1 gp120 envelope molecule appears to represent a target for naturally occurring neutralizing antibodies in HIV-1-infected individuals. In this report, we examined the extent of antibody cross-reactivity to a panel of V3-based synthetic peptides in six inbred strains of mice following repeated immunization with a baculovirus-derived recombinant gp160 (rgp160) preparation formulated with alum. The amino acid sequence of the rgp160 used in these immunizations was based upon the HIV-1 IIIB (LAI) isolate. Following five injections with rgp160, all six strains developed antibodies to the homologous IIIB-based V3 peptides, designated 304-321 and RP135. However, antibody cross-reactivity to the other nonhomologous V3 peptides was either undetectable or limited among the strains of mice examined. No in vitro neutralizing activity against HIV-1 was observed in sera from any of the six inbred strains of mice that were examined. These results suggest that repeated immunization of mouse strains with a rgp160/alum formulation leads to nonneutralizing antibodies directed against the V3 region which remain predominantly type specific. 相似文献