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31.
Massive hemorrhage caused by a perforating Gianturco-Z stent resulting in an aortoesophageal fistula
PD Siersema TG Tan FF Sutorius J Dees M van Blankenstein 《Canadian Metallurgical Quarterly》1997,29(5):416-420
Squamous cell carcinoma of the tonsil has a relatively poor prognosis. Aggressive surgery, radiation therapy and combinations of irradiation and surgery have been employed but there exists some controversy about the efficacy of these treatment modalities. The purpose of this paper is to compare the efficacy of treatment between the surgery followed by radiation therapy and the preoperative radiation therapy followed by surgical resection. The medical records of 33 patients treated for squamous cell carcinoma of the tonsil at the Department of Otolaryngology-Head and Neck Surgery, Korea University Hospital between 1989-1993 were reviewed retrospectively. None of the patients were stage I, but stage II, III, and IV were four, five, and 24 patients, respectively. There were 30 males and three females. The most common histopathology was moderately differentiated squamous cell carcinoma (20/33). The 13 patients treated initially with surgery had an overall three-year survival rate of 38.5%, and the rate for the 20 patients treated initially with radiation was 40%. The main pattern of treatment failure was a local recurrence and neck metastases, and pathologic differentiation thought to be an important prognostic factor. Complications are fewer in patients treated initially with surgery (23.1%) than patients initially treated with radiation (50.0%). There is no difference in the efficacy between the two therapeutic groups. 相似文献
32.
EJ Raubenheimer JM Brown DB Rama MJ Dreyer PD Smith J Dauth 《Canadian Metallurgical Quarterly》1998,43(8):641-647
OBJECTIVES: The purpose of the present study was to compare the inclination of the occlusal plane with occlusal guidance as a contributing factor to masticatory movement. METHODS: Masticatory movements of 41 young adults were measured using a 3-D mandibular movement analysing system. The inclination of the occlusal plane was measured in the sagittal plane using a 3-D digitizer. The contribution of the occlusal guidance and the inclination of the occlusal plane to the direction of the masticatory path of closure was evaluated at various closing levels. RESULTS: The masticatory path of closure outside the intercuspal range was influenced mainly by the inclination of the occlusal plane, and the masticatory path of closure near the intercuspal range was only influenced by occlusal guidance. The so-called gliding type masticatory pattern was observed predominantly in subjects with a posteriorly inclined occlusal plane. In contrast, a chopping type masticatory pattern was observed predominantly in subjects with an anteriorly inclined occlusal plane. CONCLUSIONS: The contribution of the inclination of the occlusal plane to masticatory movement was greater than that of occlusal guidance throughout the closing phase except near the intercuspal range. 相似文献
33.
34.
BACKGROUND: We determined whether activation of the nitric oxide/cyclic guanosine monophosphate pathway by sodium nitroprusside (SNP) protects hearts subjected to cardioplegic arrest and prolonged hypothermic storage. METHODS: Isolated rat hearts arrested with St. Thomas' II cardioplegia and stored at 3 degrees +/- 1 degree C for 8 hours were reperfused at 37 degrees C in Langendorff (10 minutes) and working (60 minutes) modes. RESULTS: During reperfusion, left ventricular work was depressed in stored hearts relative to fresh hearts. When present during arrest, storage, and both reperfusion phases, SNP (200 mumol/L) improved work to values close to those in fresh hearts. When added only during the 10-minute period of Langendorff reperfusion, SNP also improved the subsequent recovery of work. This effect was antagonized by the soluble guanylyl cyclase inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). Poststorage coronary perfusion was not increased by SNP. CONCLUSIONS: The ability of SNP to enhance recovery independent of changes in coronary perfusion and in an ODQ-sensitive manner suggests that SNP-induced protection is due to activation of the myocardial nitric oxide/cyclic guanisine monophosphate pathway. These results suggest that supplementing cardioplegic solutions with SNP, administering SNP during early reperfusion, or both may offer additional means to improve donor heart preservation. 相似文献
35.
M Schmoeckel FN Bhatti A Zaidi E Cozzi PD Waterworth MJ Tolan G Pino-Chavez M Goddard RG Warner GA Langford JJ Dunning J Wallwork DJ White 《Canadian Metallurgical Quarterly》1998,65(12):1570-1577
BACKGROUND: Previous studies demonstrated that hearts from transgenic pigs expressing human decay-accelerating factor (hDAF) were not hyperacutely rejected when transplanted heterotopically into the abdomen of cynomolgus monkeys. This study examines orthotopic transplantation of hDAF transgenic pig hearts into baboon recipients. METHODS: Orthotopic xenogeneic heart transplantation was performed using piglets, transgenic for hDAF, as donors. Ten baboons were used as recipients and were immunosuppressed with a combination of cyclophosphamide, cyclosporine, and steroids. RESULTS: Five grafts failed within 18 hr without any histological signs of hyperacute rejection. Pulmonary artery thrombosis induced by a size mismatch was observed in two of these animals. The other three recipients died because of failure to produce even a low cardiac output and/or dysrhythmia. The remaining five animals survived between four and nine days. One animal died of bronchopneumonia on day 4. Three xenografts stopped beating on day 5 due to acute vascular rejection. The longest survivor was killed on day 9 with a beating, histologically normal xenograft, because of pancytopenia. CONCLUSIONS: The results reported here demonstrate that hDAF transgenic pig hearts are not hyperacutely rejected when transplanted into baboon recipients. Orthotopically transplanted transgenic pig hearts are capable of maintaining cardiac output in baboons. An optimum immunosuppressive regimen is the subject of ongoing research. 相似文献
36.
W Staudenmann PD Hatt S Hoving A Lehmann M Kertesz P James 《Canadian Metallurgical Quarterly》1998,19(6):901-908
The main factor limiting the sensitivity range for the identification of proteins isolated by two-dimensional (2-D) electrophoresis is sample handling: protein detection limits on the gel, losses during extraction and digestion, as well as interference of gel contaminants and detergents with the mass spectrometry (MS) detection increasing background noise. At the one hundred picomole level, losses are fairly negligible but when the amounts drop below 1 picomole (and subfemtomole peptide detection limits have been reported recently by MS), the losses become a critical point. In order to extend proteome analysis to include very low copy number proteins, methods must be developed to minimize losses and handling steps, maximize digestion and extraction yields, as well as to lower chemical noise. We present several methods that we have developed in our laboratory to: (i) increase the amount of material available in a sodium dodecyl sulfate (SDS)-free form which does not require staining, (ii) increase protein extraction and digestion yields and lower the contamination by autoproteolytic products, and (iii) allow direct modification of the peptide mixture to generate sequence tags. 相似文献
37.
Helicobacter pylori eradication as a surrogate marker for the reduction of duodenal ulcer recurrence
GA Neil LJ Suchower E Johnson PD Ronca ML Skoglund 《Canadian Metallurgical Quarterly》1998,12(7):619-633
OBJECTIVES: An abundance of data exists documenting the association of H. pylori eradication with the reduction in duodenal ulcer recurrence. AIM: To evaluate the validity of using H. pylori eradication as a surrogate marker for the reduction in duodenal ulcer recurrence using rigorously controlled studies. METHODS: Three controlled clinical trials were conducted in patients with uncomplicated, active duodenal ulcers. Patients were treated with various combinations of omeprazole and amoxycillin. Ulcer healing and H. pylori eradication were assessed. For patients whose duodenal ulcer healed, duodenal ulcer recurrence was determined over a 6-month period in patients with H. pylori eradication and those remaining positive for H. pylori at least 4 weeks after treatment. To support the data obtained from these clinical trials, a search of the medical literature was conducted to identify additional human clinical trials in which duodenal ulcer recurrence rates were measured and categorized by H. pylori status at least 1 month post-treatment. RESULTS: In 11 controlled trials, the overall 6-18-month duodenal ulcer recurrence rate was 54% among patients remaining positive for H. pylori at least 4 weeks after treatment compared to 6% among patients with H. pylori eradication following treatment. This finding was corroborated by the uncontrolled trials, in which the duodenal ulcer recurrence rate was 64% among patients found to be H. pylori-positive and 6% for patients found to be H. pylori-negative at least 4 weeks after treatment. A time course of duodenal ulcer recurrence rates using pooled data from both controlled and uncontrolled studies demonstrated that duodenal ulcer recurrence rates for H. pylori-negative patients persisted for up to 4 years following treatment. Duodenal ulcer recurrence rates for H. pylori-positive patients increased for the first year, then levelled off. A comparison of the duodenal ulcer recurrence rates for different treatment regimens revealed that eradication regimens based on omeprazole plus antibiotics and bismuth plus antibiotics exhibited similar duodenal ulcer recurrence rates for H. pylori-positive and -negative patients. CONCLUSION: Regardless of treatment regimens, H. pylori eradication produced a consistent and significant reduction in duodenal ulcer recurrence. Therefore H. pylori eradication, 4 weeks post-therapy, can be used as a surrogate marker for reduced duodenal ulcer recurrence in investigational clinical trials. 相似文献
38.
GW Mathern JK Pretorius HI Kornblum D Mendoza A Lozada JP Leite L Chimelli DE Born I Fried AC Sakamoto JA Assirati WJ Peacock GA Ojemann PD Adelson 《Canadian Metallurgical Quarterly》1998,5(3):151-176
This study determined whether hippocampal kainate (KA) receptor mRNA levels were increased or decreased in temporal lobe epilepsy patients compared with nonseizure autopsies. Hippocampal sclerosis (HS; n = 17), nonsclerosis (non-HS; n = 11), and autopsy hippocampi (n = 9) were studied for KA1-2 and GluR5-7 mRNA levels using semiquantitative in situ hybridization techniques, along with neuron densities. Compared with autopsy hippocampi, HS and non-HS cases showed decreased GluR5 and GluR6 hybridization densities per CA2 and/or CA3 pyramid. Furthermore, HS patients demonstrated increased KA2 and GluR5 hybridization densities per granule cell compared with autopsy hippocampi. These findings indicate that chronic temporal lobe seizures were associated with differential changes in hippocampal KA1-2 and GluR5-7 hybridization densities that vary by subfield and pathology group. In temporal lobe epilepsy patients, these results support the hypothesis that pyramidal cell GluR5 and GluR6 mRNA levels are decreased as a consequence of seizures, and in HS patients granule cell KA2 and GluR5 mRNA levels are increased in association with aberrant fascia dentata mossy fiber sprouting and/or hippocampal neuronal loss. 相似文献
39.
Fibro-osseous lesions of the sinonasal region are relatively frequent, but those strictly confined to the nasal cavity are rare. We report an atypical fibro-osseous lesion in the nasal cavity and describe its radiological features. The differential diagnosis is discussed. 相似文献
40.
A survey of radiographic technique and estimated entrance surface dose has been carried out for 364 chest radiographs performed with mobile X-ray equipment in the Intensive Therapy Unit (ITU) and 30 wards at Aberdeen Royal Infirmary. Data for these two types of location were compared, as were those for two film/screen systems used on the wards. Image quality assessments were made on sets of radiographs for two patients. Entrance skin doses for chest radiographs performed in the ITU were 50% greater than on the wards with the same film/screen system. The main technique difference was the use of shorter focus-to-skin distances (FSDs) in ITU. Doses with the Kodak Insight system were 20% higher than those using Du Pont Quanta III in similar locations. No correlation was found between image quality and entrance surface dose (ESD). Results from the survey were used to recommend exposure factors for shorter FSDs. A follow-up study revealed a 35-45% reduction in ESD for Kodak Insight and a 20% reduction for Quanta III. 相似文献