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41.
42.
BACKGROUND: To evaluate the efficacy and toxicity of cisplatin/etoposide continuous infusion chemotherapy for cancer of unknown primary site in Taiwan, a region with a high prevalence of endemic viral infections. METHOD: Between April 1994 and February 1996, 20 patients with a diagnosis of CUPS were treated, including 15 males and five females, of average age 63.3 years (range 41-83 years). Continuous intravenous infusion of etoposide 80 mg/m2 and cisplatin 25 mg/m2 was given for 3 days every 3 weeks. Pretreatment tumor marker and viral serology studies were performed for baseline evaluation. Nearly two-thirds of the patients had poorly differentiated carcinoma. The average number of metastatic sites was 2.65 (range 1-4), with liver and lymph node involvement predominating. RESULTS: The overall response rate was 25% (95% CI 17.7-32.3%); 30.7% for poorly differentiated cancers and 25% for well differentiated cancers. Median survival was 4 months (range 1-12 months), 4.8 months for patients attaining partial response. Toxicity was moderate, grade 3 and 4 neutropenia occurred in 55% and grade 3 and 4 thrombocytopenia in 40%; other toxicities were mild. CA125 and CA199 were elevated in more than 50% of patients. Viral serology studies were not significantly different from those of the indigenous population. CONCLUSION: Etoposide and cisplatin combination chemotherapy has modest activity in patients with extensive CUPS and, at the schedule and dosage given, it is associated with moderate toxicity.   相似文献   
43.
Inflamed fibronectin: an altered fibronectin enhances neutrophil adhesion   总被引:4,自引:0,他引:4  
Vercellotti  GM; McCarthy  J; Furcht  LT; Jacob  HS; Moldow  CF 《Blood》1983,62(5):1063-1069
Recent investigations have emphasized the role of activated granulocytes in mediating vascular endothelial injury in the pathogenesis of shock lung. In vitro studies have indicated that tight adherence of the neutrophil to the endothelium is crucial for the development of cellular injury. Fibronectin is critical to cell-to- substratum and cell-to-cell interactions. Since fibronectin resides in plasma, on endothelial cell surfaces and is secreted into cell matrices, the adhesive properties of fibronectin must be modulated, lest universal cell agglomeration occur, yet be enhanced when cell attachment is appropriate. In these studies, treatment of fibronectin- coated surfaces with neutrophil release products increased the adhesion of activated neutrophils. Similarly, endothelial cells treated with neutrophil release products become a more adherent substrate for neutrophils. This enhanced adherence generated by treatment of fibronectin with neutrophil supernatants is inhibitable by heat and the lysosomal proteinase inhibitor, pepstatin-A. Neutrophil release products cause proteolytic fragmentation of fibronectin and enhanced fibronectin immunofluorescence on endothelial cells. In addition, neutrophils are more injurious to endothelial cells that have been pretreated with neutrophil release products. Neutrophils may enhance their own adherence to endothelial cells by altering fibronectin, and this altered, or "inflamed," fibronectin may serve as an amplifier of inflammation.  相似文献   
44.
Hairy leukoplakia (HL) is a lesion found on the side of the tongue of immunocompromised individuals, including those with human immunodeficiency virus (HIV) infection. The lesion has unique histopathologic features and is characterised by high-level Epstein-Barr virus (EBV) replication, multiple EBV strains, and extensive inter-and intra-strain recombination. Expression of EBV genes spanning the entire viral life cycle from latency-associated genes to late, replicative genes has been detected in the lesion. HL thus provides a unique opportunity to study EBV expression in oral epithelium, and to study expression of novel EBV genes. We therefore constructed a cDNA library from an HL biopsy and detected expression of two genes not previously described in vivo: BMRF-2 and BDLF-3. Sequence analysis of the cDNAs revealed few amino acid changes from the B95-8 sequence. Expression of both genes was localized to the lower prickle cell layer of the tongue epithelium. BMRF-2 protein expression was primarily detected in the cell nuclei of the upper prickle cell layer. BDLF-3 protein expression was observed in the perinuclear space and Golgi compartment. The function of these proteins is currently under investigation.  相似文献   
45.
A case of metastatic carcinoma of the left atrium is described. The correct antemortem diagnosis was made on the basis of electrocardiographic changes resembling atrial infarction. These included deformed P waves, deviation of the P-Ta segments and atrial arrhythmias.  相似文献   
46.
Primary failure of tooth eruption rarely occurs. This case represents a rare clinical situation and appears to reflect a generalized disturbance in the eruptive process, inasmuch as (1) deciduous and permanent dentition are affected, (2) incisors, molars, and premolars are involved in all quadrants, (3) skeletal and craniofacial growth are within normal limits, and (4) no systemic/genetic anomalies were detected. This is the first such case reported in the literature; diagnosis and management are discussed.  相似文献   
47.
48.
Intracranial meningiomas: high-field MR imaging   总被引:6,自引:0,他引:6  
  相似文献   
49.
Ocular and orbital lesions: surface coil MR imaging   总被引:1,自引:0,他引:1  
Nine lesions, four ocular (three melanomas, one hemangioma) and five orbital (two perioptic meningiomas, one hemangioma, one pseudotumor, one mucocele), were evaluated by magnetic resonance surface coil imaging at 1.5 T. Small ocular lesions with 3.9-4.5-mm-elevation were demonstrated. The use of two different pulse sequences resulted in separation of melanoma from adjacent retinal detachment. Contrast obtained between orbital lesions and the adjacent normal structures was better than that demonstrated with high-resolution computed tomography.  相似文献   
50.
Epithelial pathways for luminal entry of bulk plasma   总被引:1,自引:0,他引:1  
Inflammatory challenges of the airway mucosa cause luminal entry of bulk plasma. Extravasation of plasma is well described but the routes for epithelial passage of plasma are largely unknown. Using colloidal gold (5 nm) as tracer we have now examined the fate of extravasated plasma in the airways. The tracer was given intravenously to anaesthetized, ovalbumin-sensitized guinea-pigs 2min prior to airway mucosal challenge with 12pmol ovalbumin (the dose was selected from a separate dose-response study). Tissue specimens were collected 30s, 3 and 6 min after end of challenge (separate time course experiments suggested that the peak rate of entry of plasma occurred at about 5 min). The colloidal gold particles were visualized by autometallographic silver intensification. The gold produced no circulatory disturbance and had a uniform vascular distribution with negligible adherence to vascular endothelium. After challenge gold was first widely distributed in the lamina propria. At 3 and 6 min the tracer was also in the epithelium and airway lumen. It appeared that plasma was moved distinctly between and all around each epithelial cell. Bright field-, scanning-, and transmission electron-microscopy indicated that the luminal entry of plasma did not affect the integrity of the epithelial lining. This study demonstrates that the plasma exudate moves across an intact epithelial layer through ubiquitous paracellular pathways. Even at a pronounced acute plasma exudation response exceedingly small amounts of plasma may pass around a single cell explaining the non-injurious nature of mucosal exudation of bulk plasma in health and disease.  相似文献   
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