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One hundred six patients underwent extracorporeal shock wave lithotripsy for cholelithiasis. Of these, 28 patients underwent cholangiographically guided lithotripsy for bile duct stones to assist nonoperative stone removal by endoscopic or radiologic intervention. Fragmentation occurred in 20 of 28 cases (71%) with an average of two lithotripsy sessions. Hemobilia was observed in four patients (14%) for a 24-hour period. Seventy-eight of the 106 were outpatients with symptomatic cholecystolithiasis with one to five calculi who underwent cholecystographic or ultrasound-(US) guided shock wave lithotripsy as definitive therapy. US examination showed stone fragmentation in 86% of cases. With an average of 1.6 treatment sessions and 4,750 shocks, fragments were 4 mm or smaller in 46% of patients. Nine percent of patients had no fragments after an average of 10 weeks, but long-term follow-up is not yet available. Two patients developed acute pancreatitis attributable to fragment passage and one patient acute cholecystitis, likely due to cystic duct obstruction by a fragment. 相似文献
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Risk factors for metastatic uveal melanoma after trans-scleral local resection. 总被引:10,自引:8,他引:2 下载免费PDF全文
AIMS: This study reports the metastatic death rate after trans-scleral local resection of uveal melanoma and identifies relevant risk factors. METHODS: Local resection was performed in 332 patients (mean age 51 years), with follow up ranging to 20.9 years (median for living patients 33 months). The tumours had a mean largest basal diameter of 13.1 mm and mean thickness of 7.5 mm, with 135 containing epithelioid cells. Risk factors were identified by Cox analysis and metastatic rates demonstrated using Kaplan-Meier curves. RESULTS: There were 52 deaths from metastatic melanoma. The significant risk factors were (i) age more than 60 years at treatment (p = 0.001), (ii) mixed/epithelioid tumours (p = 0.003), (iii) superior location of mixed/epithelioid tumours (over and above (ii)) (p = 0.001), (iv) largest basal tumour diameter of 16 mm or more (p < 0.001), (v) lack of adjunctive radiotherapy (p = 0.031), (vi) secondary enucleation for bulky residual/recurrent tumour (p = 0.002), and (vii) secondary enucleation for small residual/recurrent tumour extraocularly (p = 0.019). Metastatic death was not significantly associated with (i) incomplete tumour excision (p = 0.163), and (ii) small residual/recurrent tumour treated by enucleation (p = 0.855). CONCLUSIONS: Survival diminished from 92% at 15 years if less than two risk factors were present to less than 30% in 3.5 years if more than three risk factors were present. 相似文献
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BACKGROUND: White cell (WBC)-reduced platelet concentrates (PCs) are defined by their absolute WBC count, a criterion which provides no information regarding the various WBC subsets contained in the PC. These heterogeneous cells are known to mediate different physiologic and pathophysiologic functions and account for distinct adverse transfusion responses. This study describes a method which allows the detection and quantification of these subsets and characterizes their presence in a variety of platelet components. STUDY DESIGN AND METHODS: Random-donor pooled PCs (RD PCs) and single-donor apheresis PCs (SD PCs) were studied. RD PCs consisting of 6 units of 2- to 3-day old PCs were randomly assigned to be filtered with one of four WBC-reduction filters from three different manufacturers (n=34). The residual WBCs were pelleted by centrifugation and isolated on a density gradient. The various WBC subsets were quantified by flow cytometry in unfiltered and filtered PCs using fluorescence and two-angle light scatter. SD PCs obtained with two manufacturer's systems and three processing protocols (n=30) were studied in like manner. RESULTS: WBC counts for non-WBC- reduced PCs averaged 3 × 10(8) in RD PCs and ranged from 8.6 to 9.6 × 10(6) per SD PC. Residual WBC counts in filtered PCs ranged from 2.3 × 10(4) to 2.2 × 10(5) and those in WBC-reduced SD PCs averaged 2.2 × 10(5) per unit. The data demonstrate significant phenotypic differences among PCs produced with various procedures. All SD PCs and two of four filtered RD PCs contained five WBC populations including granulocytes and monocytes, while RD PCs filtered with the remaining manufacturer's devices contained only lymphocytes. CONCLUSION: The data confirm that distinct phenotypic differences exist among PCs prepared with different devices and/or procedures. It is suggested that as for non-generic pharmaceuticals, the clinical benefits of these various PCs should be individually proved. 相似文献
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When bovine neural retinas are incubated in Krebs-Henseleit buffer with D-[3H]-galactose, autoradiography reveals that there is a rapid uptake of the tritium label into the inner segments of cones, but not of rods. Pulse--chase studies show that the label is first associated with the Golgi apparatus in the cones, then appears to travel around the nucleus and along the cone fibre (homologous to an axon) to the synaptic pedicle. The cone-specific label travels along the fibre at a rate of about 0.5-1.0 mm per day. Label is also found in endothelial cells and Müller cells, but does not persist in the Müller cells as long as in the cones. The striking difference between rod and cone labelling may reflect fundamental differences in the neurochemistry of these two photoreceptor cell types. 相似文献
160.
The effect of malonyldialdehyde on erythrocyte deformability 总被引:7,自引:0,他引:7
The addition of malonyldialdehyde (5-20 micro M) to human erythrocytes results in a marked decrease in cellular deformability as measured with a counter-rotating, cone plate Rheoscope when low shear forces (2.5-25 dynes/sq cm) are applied. At high shear forces (125-500 dynes/sq cm), malonyldialdehyde at 5 micro M had no effect on deformability, although at concentrations of 10 and 20 micro M a small but statistically significant decrease was evident. These effects of this crosslinking agent are observed in the absence of alterations in cell volume and intracellular viscosity. The results obtained are in accord with the view that the polymerization of membrane constituents may contribute to the events that lead to the removal from the circulation of either aging cells or cells exposed to peroxidation-initiating agents. 相似文献