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31.
32.
This report describes the use of transluminal endovascular grafting for the treatment of a presumed aortoduodenal fistula. The patient was a 71-year-old man who had undergone resection and graft replacement for an abdominal aortic aneurysm. Three years after operation, melena was caused by perforation of the duodenal wall by a pseudoaneurysm at the proximal graft anastomosis. The pseudoaneurysm was treated by transluminal endovascular grafting. The pseudoaneurysm was subsequently thrombosed and absorbed. The ulcer-like lesions at the site of the duodenal wall perforated by the pseudoaneurysm also resolved. Endovascular stent-grafts may have a role to play in management of aortoduodenal fistula.  相似文献   
33.
Abstract: Pyridoxalated-hemoglobin-polyoxyethylene conjugate (PHP), which is made from out-dated human red blood cells by two major chemical modifications, namely pyridoxalation and conjugation with polyoxyethylene (POE), is currently under development as a physiological oxygen carrier. This study assessed the effects of PHP-88 solution, which contains 8% (wt/vol) each of hemoglobin (Hb) and maltose, on renal function when it was infused 3 times every other day into the intact circulation of 8 dogs (5 dogs for the PHP group and 3 for the control group; 20 ml/kg for the first infusion, and 10 ml/kg each for the second and third infusions, at the rate of 2.5 ml/h/kg). Serial determinations of glomerular filtration rate (GFR) and renal plasma flow (RPF) were carried out pre- and postinfusion for up to 3 months along with measurements of blood and urine analyses, urine output rate, fractional excretion of sodium (FES), and free water clearance (CH2O). The results showed that plasma colloid osmotic pressure (COP) elevated an average of 3.3 mm Hg (p = 0.0085), and GFR and RPF tended to increase by 13% (NS) and 38% (NS), respectively, immediately after the third infusion with PHP solution. Urine output rate increased during and after the infusion, and FES and CH2O also increased for 24 h after the infusion in both groups. Blood urea nitrogen, serum creatinine, and serum Na+ concentrations were not affected greatly by the infusions, but hematocrit was decreased by 8% in the PHP group, indicating approximately a 42% expansion of plasma volume. These changes were observed to return to their preinfusion levels by 1 week postinfusion. Renal histology of the PHP group obtained at 2 weeks postinfusion revealed vacuole formation in the proximal tubules which was not associated with any pathologic changes indicative of cell death or regeneration. In 4 out of 5 dogs at 3 months postinfusion (necropsy), the vacuoles were not present. Though urinary N-acetyl β-glucosaminidase (NAG) activity had significantly increased after infusion, it returned to the preinfusion level by 1 month postinfusion. No detrimental effect of vacuoles on the assessed renal tubular functions was confirmed in the present study. The result demonstrated that multiple infusions of PHP solutions were well tolerated in normal dogs, and the observed effects were conceived predominantly attributable to the physiological response of the kidneys to an oncotic load into the circulation, which produced plasma volume expansion.  相似文献   
34.
The present study was undertaken to elucidate the effect on platelet aggregation of the prothrombin-converting reaction on platelets with or without activated protein C (APC). A reaction mixture of washed platelets from human individuals, Factor Xa and prothrombin markedly induced platelet aggregation; maximum aggregation rates, 31.3–92.5%, and times to reach to maximum aggregation, 11.6 to 20.1 min. This aggregation was inhibited by the addition of APC with 50% inhibition concentration (IC50) value of 14.4 U/ml. APC also inhibited thrombin generation in the reaction mixture in a dose-dependent manner with IC50 value of 0.96 U/ml. However, APC did not inhibit the thrombin (0.1 CU/ml)-induced platelet aggregation at concentrations of up to 30 U/ml. These findings suggest that APC has no direct inhibitory effect on platelet aggregation and that APC inhibits platelet aggregation through inhibition of thrombin generation.  相似文献   
35.
Thrombotic microangiopathy (TMA) may develop after living donor liver transplantation (LDLT), but the mechanism is not fully understood. We retrospectively analyzed all patients undergoing LDLT at our center, including TMA patients, to elucidate the clinical characteristics and presentation and to determine which patients have a higher risk of occurrence of TMA. In all, 57 adult patients were reviewed after LDLT at our institution. TMA was diagnosed by sudden and severe thrombocytopenia, followed by hemolytic anemia with fractionated erythrocytes in the blood smear. Clinical features were compared between the TMA group and the non-TMA group. Of the 57 patients, 4 were diagnosed with posttransplantation TMA. ABO blood group (ABO)-incompatibility, cyclophosphamide (CPA), and recipient blood group (type O) were closely correlated with the occurrence of TMA. Thrombocytopenia appeared 1 to 5 days before hemolytic anemia. Coagulative function markers stayed at the same level after TMA, while marked elevation was shown in fibrinolytic function markers such as plasminogen activator inhibitor type 1 (PAI-1). TMA occurred at a higher prevalence in ABO-incompatible graft recipients. Additional factors associated with ABO-incompatible transplantation, such as an overdose of immunosuppressants, may affect the likelihood of TMA. Sudden and severe thrombocytopenia presented before hemolytic anemia and the serum levels of PAI-1 correlated well with the clinical course of TMA. In conclusion, early recognition of thrombocytopenia and elevation of PAI-1 is crucial to diagnose TMA especially in ABO-incompatible LDLT.  相似文献   
36.
OBJECTIVES: In the assessment of Raynaud's phenomenon, objective evaluation of digital microcirculatory flow is important, and so we investigated whether the measurement of laser Doppler skin perfusion pressure could be of use. MATERIALS AND METHODS: Ten fingers of five patients with secondary Raynaud's phenomenon due to systemic sclerosis, 22 fingers of 11 patients with primary Raynaud's phenomenon and 10 fingers of five control patients were examined. Skin perfusion pressure was measured on the third finger of both hands at rest, and then again 3 min after local cold exposure. RESULTS: Laser Doppler skin perfusion pressure at rest in patients with secondary Raynaud's phenomenon was significantly lower than that in patients with primary Raynaud's phenomenon and the control patients (p<0.05). Skin perfusion pressure decreased significantly in both patient groups upon local cold exposure (p=0.005). There were significant differences in perfusion pressure after cold exposure among both groups (p<0.05). CONCLUSIONS: The low skin perfusion pressure at rest in patients with secondary Raynaud's phenomenon suggested the presence of obstructive arterial lesions. The marked pressure decrease in all Raynaud's patients after local cold exposure might be due to vasospasm of the microvasculature in the digits. These results indicate that the measurement of laser Doppler skin perfusion pressure is valuable in the diagnosis of Raynaud's phenomenon.  相似文献   
37.
In order to examine the pathology in patients with obstructive sleep apnoea/hypopnoea syndrome (OSAHS), the nonlinear properties of respiratory movement and breath-to-breath variations during resting wakefulness with eyes closed was investigated. Recording of the respiratory movement using inductive plethysmography was performed on 14 patients with OSAHS and 13 control subjects for 2 h in the supine position during daytime. To calculate the correlation dimension (D2) for respiratory movement, an algorithm proposed by Grassberger and Procaccia was applied. The indices of breath-to-breath variations were estimated. To calculate D2 and breath-to-breath variations, two different segments were selected (200 s each). The value of D2 for respiratory movement in patients with OSAHS was significantly greater than that in control subjects. In the case of > or = 2.0 of D2 for respiratory movement, the sensitivity and specificity of detecting the presence of OSAHS was 85.7% and 76.9%, respectively. On the basis of breath-to-breath variations, only the coefficient of variation of expiratory time for respiratory movement in patients with OSAHS was significantly greater than that in the control subjects. In conclusion, the measurements of correlation dimensions for respiratory movement with a brief period during wakefulness may be a useful index for identifying patients with obstructive sleep apnoea/hypopnoea syndrome.  相似文献   
38.
A rare adult case of a left ectopic ureterocele associated with a duplex horseshoe kidney is reported. To the best of our knowledge, only one pediatric case of horseshoe kidney with an ectopic ureterocele has been reported. The present case was successfully treated by ureteropyelostomy, upper ureterectomy and unroofing of the ureterocele. The patient is currently followed with excretory urograms and renograms.  相似文献   
39.
In a patient with primary lung cancer, increased accumulation of I-123-IMP was observed in a pulmonary inflammatory lesion surrounding a lung cancer which was delineated as a photon deficient area. Ga-67-citrate uptake was observed in both the inflammatory and cancerous areas. These findings suggest that I-123-IMP may have the potential to accumulate differently in a variety of pathological conditions of the lung and thus may be a clinically useful lung imaging agent.  相似文献   
40.
Delayed manifestation of aortic stenosis caused by abdominal blunt trauma is rare. We report herein the case of a 67-year-old man who was taken to a nearby hospital after being crushed between a heavy truck and a wall. An emergency laparotomy was performed, revealing only a mesenteric tear which was repaired. He was discharged after an uneventful postoperative course; however, 1 month later he began to experience intermittent claudication, and presented to our hospital in December 1994, 1 year after the first operation. Angiography and enhanced computed tomography (CT) demonstrated infrarenal abdominal aortic dilatation with distal stenosis. Both the dilated and stenotic lesions were resected and bypass surgery was performed. Pathologic examination demonstrated that the intima had been lacerated circumferentially and everted distally, causing the aortic stenosis. To our knowledge, this is the first case of the delayed manifestation of traumatic aortic stenosis to be documented in Japan. The etiology of this rare complication of blunt trauma is described in this report.  相似文献   
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