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71.
Retained or recurrent stones in the common bile duct remain a clinical problem in 2% to 5% of patients undergoing cholecystectomy. Nonoperative extraction via the T tube tract or endoscopic sphincterotomy is successful in 85% to 95% of patients; however, the remainder require reoperation. This study evaluates the efficacy of electrohydraulic shock wave lithotripsy therapy of common duct stones too large to be extracted endoscopically or by T tube. Six patients were entered into the study. Ages ranged from 62 to 93 years. All patients either had severe preexisting systemic disorders or were of an advanced age. Stones ranged in size from 10 to 41 mm, with a mean largest dimension of 22 mm. In all patients either extraction by traditional nonoperative means failed or there was a stone that was considered to be too large to be extracted successfully. Patients were treated with 1200 to 2400 shocks at 16 to 20 kV. Five of six patients were treated with local anesthesia and sedation. Stones were successfully fragmented in all but one patient. Five patients required extraction of the remaining fragments either through the T tube tract (one patient) or via endoscopic sphincterotomy. All patients were free of stones at discharge, with the exception of one patient with severe cirrhosis who had an intrahepatic stone behind a right hepatic duct stricture. This stone had been successfully fragmented but an endoscopic retrograde cholangio-pancreatogram revealed some residual fragments despite normal alkaline phosphatase and bilirubin values. There were no hospital deaths, although the patient with the intrahepatic stone died of bleeding varices several months later. Electrohydraulic shock wave lithotripsy seems to be an effective adjuvant treatment in clearing the bile duct of stones that would otherwise require reoperation.  相似文献   
72.
In rabbits undergoing peritoneal dialysis, hypertonic (6% dextrose) dialysis solution increased the net ultrafiltration rate (UF) from 233 to 462 microL/kg/min, which was not proportional to the increment in the osmotic gradient, so the ultrafiltration coefficient decreased. As intraperitoneal dwell of hypertonic dialysate was prolonged, the gross and net UFs and ultrafiltration coefficients decreased, and the UF per dextrose absorption declined. The decrement in UF was multifactorial, including a component of fluid and solute stagnation, increasing the distance over which osmotic forces must exert their effects. Excessively hypertonic dialysis fluid should be used only briefly to achieve ultrafiltration efficiently and to avoid the high dextrose loading.  相似文献   
73.
The impact of elevated vascular endothelial growth factor (VEGF) expression on the course of chronic myeloid leukemia (CML) is unknown. By radioimmunoassay, we measured pretreatment cellular VEGF protein in bone marrow samples from 184 (148 chronic and 36 accelerated/blastic phases) CML patients and found the levels to be 1.6-fold higher than in 31 normal control bone marrow samples (P =.000 01). No significant differences were found in VEGF levels by different phases of CML (P =.1). VEGF levels correlated with older age (P =.01) and higher platelet count (P =.0003), but also with smaller spleen size (P =.004), lower white blood cell count (P =.0006), and lower percentage of peripheral blasts (P =.04). With the use of Cox proportional hazard model and VEGF levels as a continuous variable, high VEGF levels correlated with shorter survival of patients in chronic CML (P =.008). Multivariate analysis showed that VEGF was not independent of the synthesis stage (P =.09). These data suggest that VEGF plays a role in the biology of CML and that VEGF inhibitors should be investigated in CML.  相似文献   
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Microtubule reassembly in surface-activated platelets   总被引:2,自引:0,他引:2  
White  JG; Krumwiede  M; Sauk  JJ 《Blood》1985,65(6):1494-1503
It is generally accepted that a circumferential microtubule supports the discoid shape of resting platelets. The fate of the many-coiled polymer following platelet activation, however, has been a subject of considerable debate. Morphological investigations have suggested that the circumferential coils are constricted into tight rings around centrally concentrated organelles during platelet shape change. Biochemical studies employing colchicine-binding assays, on the other hand, have indicated that the bundle of microtubules dissolves almost completely within seconds after activation and reassembles in a new location one to four minutes later. The present study has accepted the latter hypothesis in order to examine the second part of the disassembly-reassembly theory proposed in biochemical studies. Platelets exposed to low temperatures sufficient to remove all microtubules were placed on glass slides and microscope grids to cause surface activation during rewarming. The combined stimuli of rewarming and surface activation might have been expected to cause more rapid assembly than warming alone or activation alone. This was not the case. Reassembly of microtubules during rewarming and simultaneous surface activation was not accelerated. In contrast to the constriction of microtubule rings observed during activation in control platelets, the diameters of coils that developed in chilled platelets one to two hours after rewarming and surface activation were twice those of control cells.  相似文献   
76.
Impact of body weight on long-term survival after lung transplantation   总被引:3,自引:0,他引:3  
Kanasky WF  Anton SD  Rodrigue JR  Perri MG  Szwed T  Baz MA 《Chest》2002,121(2):401-406
STUDY OBJECTIVES: The purpose of this study was to determine the impact of a pretransplantation determination of body mass index (BMI) on survival after lung transplantation. DESIGN AND PATIENTS: Univariate and multivariate survival analyses of a single institution database consisting of 85 patients who had undergone lung transplantations between March 1994 and October 1998. SETTING: University of Florida Health Science Center. RESULTS: Kaplan-Meier survival curves showed that patients who were obese (ie, BMI, > or = 30) at a pretransplantation assessment had a marked decrease in posttransplantation survival time (log rank, p < 0.05; Wilcoxon, p < 0.05). The final Cox regression model revealed that the most powerful predictors of mortality after lung transplantation were higher pretransplantation BMI and the development of obliterative bronchiolitis. CONCLUSIONS: Our results suggest that the posttransplantation risk for mortality is possibly three times greater for obese patients than for nonobese patients. Additional study is needed to identify the mechanisms for such higher risk in obese patients. Our data also suggest that transplantation centers should not routinely reject underweight patients (ie, BMI, < 18.5) or overweight patients (ie, BMI, 25 to 29.9) for lung transplantation listing solely on the basis of weight, as their outcomes may not be significantly different than patients with normal BMIs.  相似文献   
77.
GeroScience - Adults aged 60 and over are most vulnerable to mild traumatic brain injury (mTBI). Nevertheless, the extent to which chronological age (CA) at injury affects TBI-related brain aging...  相似文献   
78.
Clinical Rheumatology - To determine the proportion of patients admitted to the hospital for back pain who have nonserious back pain, serious spinal, or serious other pathology as their final...  相似文献   
79.
80.
Connective tissue biology and hepatic fibrosis: report of a conference   总被引:16,自引:0,他引:16  
The past 15 years have seen major advances in the characterization of extracellular matrix proteins and structure of matrix. As a by-product of this work, investigators now have an array of molecular and immunological reagents for monitoring matrix metabolism. Progress in the isolation and culture of individual cell types from liver has made possible direct measurement of matrix protein production and also has opened the way to studies of matrix degradation. The expanding knowledge of soluble mediators of inflammation is being applied to the regulation of matrix protein synthesis and degradation. Finally, experimental models of fibrosis in vivo are available for defining the complexity of matrix metabolism in the intact tissue and for validating the findings from cell culture and in vitro systems.  相似文献   
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