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1.
Background: Adenosine triphosphate-regulated potassium channels mediate protection against myocardial infarction produced by volatile anesthetics and opioids. We tested the hypothesis that morphine enhances the protective effect of isoflurane by activating mitochondrial adenosine triphosphate-regulated potassium channels and opioid receptors.

Methods: Barbiturate-anesthetized rats (n = 131) were instrumented for measurement of hemodynamics and subjected to a 30 min coronary artery occlusion followed by 2 h of reperfusion. Myocardial infarct size was determined using triphenyltetrazolium staining. Rats were randomly assigned to receive 0.9% saline, isoflurane (0.5 and 1.0 minimum alveolar concentration [MAC]), morphine (0.1 and 0.3 mg/kg), or morphine (0.3 mg/kg) plus isoflurane (1.0 MAC). Isoflurane was administered for 30 min and discontinued 15 min before coronary occlusion. In eight additional groups of experiments, rats received 5-hydroxydecanoic acid (5-HD; 10 mg/kg) or naloxone (6 mg/kg) in the presence or absence of isoflurane, morphine, and morphine plus isoflurane.

Results: Isoflurane (1.0 MAC) and morphine (0.3 mg/kg) reduced infarct size (41 +/- 3%; n = 13 and 38 +/- 2% of the area at risk; n = 10, respectively) as compared to control experiments (59 +/- 2%; n = 10). Morphine plus isoflurane further decreased infarct size to 26 +/- 3% (n = 11). 5-HD and naloxone alone did not affect infarct size, but abolished cardioprotection produced by isoflurane, morphine, and morphine plus isoflurane.  相似文献   

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Purpose: Primary obstructive megaureter (POM) is an uncommon disease in adults. We reviewed our experience with this disease to determine the clinical profile, management and prognosis of this disease in adults. Methods: We studied 37 adults with POM who presented from January 1989 to December 1998. Their clinical presentation, renal function, radiologic data, complications, treatment as well as the results and follow-up were studied. Results: The patients' age ranged from 13 to 52 years. Male : female ratio was 27 : 10. Seven patients had bilateral disease. All patients were symptomatic excepting 2. Complications at presentation were loin pain (26 cases), urinary infection (15 cases), calculus disease (17 cases), azotaemia (5 cases), and obstructive jaundice (1 case). Associated congenital anomalies included contralateral renal agenesis (2 cases), posterior urethral valve (1 case) and exstrophy of bladder (1 case). Thirty-four patients required surgical intervention. Of these, 26 patients underwent ureteroneocystostomy (UNC) with ureteral tailoring in 18 patients; 4 patients were treated endoscopically by ureteric meatotomy and stenting, 2 patients with nonfunctioning kidney by nephroureterectomy, 2 patients in advanced renal failure by percutaneous nephrostomy alone. In 4 out of 5 patients uraemia did not improve despite adequate drainage. Conclusion: The majority of adults with POM are symptomatic, have complications and require surgical correction. Complications of stone formation (46%) and renal failure (13.5%) are unusually common in adults. Once renal failure is advanced, intervention appears futile, therefore, it is imperative to treat these patients as soon as possible. Surgical correction by ureteric reimplantation is effective and has low morbidity.  相似文献   
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Urethral hemangioma: Laser treatment   总被引:3,自引:0,他引:3  
Urethral hemangioma is a rare cause of hematuria for which variousmodalities of treatment have been used. We report a young patient, whopresented with hematuria and in whom urethrocystoscopy showed multiplehemangiomas in penile urethra. These were fulgurated successfully withNd-YAG laser. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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A great variety of foreign bodies in the urethra have been reported in the literature. Mostly, these cases were reported to emphasize the unusual nature of the objects requiring technical modifications for their removal. We report an interesting case of self introduced open thumb forceps into the urethra and technique of its retrieval.  相似文献   
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Primary intraocular lymphoma (PIOL) is an ocular malignancy that is a subset of primary central system lymphoma (PCNSL). Approximately one-third of PIOL patients will have concurrent PCNSL at presentation, and 42–92% will develop PCNSL within a mean of 8–29 months. Although rare, the incidence has been rising in both immunocompromised and immunocompetent populations. The majority of PIOL is diffuse large B-cell lymphoma, though rare T-cell variants are described. Recently, PIOL has been classified by main site of involvement in the eye, with vitreoretinal lymphoma as the most common type of ocular lymphoma related to PCNSL. Diagnosis remains challenging for ophthalmologists and pathologists. PIOL can masquerade as noninfectious or infectious uveitis, white dot syndromes, or occasionally as other neoplasms such as metastatic cancers. Laboratory diagnosis by cytology has been much aided by the use of immunocytochemistry, flow cytometry, biochemical finding of interleukin changes (IL10:IL6 ratio > 1), and cellular microdissection with polymerase chain reaction amplification for clonality. Use of several tests improves the diagnostic yield. Approaches to treatment have centered on systemic methotrexate-based chemotherapy, often with cytarabine (Ara-C) and radiotherapy. Use of intravitreal chemotherapy with methotrexate (0.4 mg/0.1 mL) is promising in controlling ocular disease, and intravitreal rituximab (anti-CD20 monoclonal antibody) has also been tried. Despite these advances, prognosis remains poor.  相似文献   
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In a cross-sectional study of 641 Schistosoma japonicum-infected individuals in Leyte, Philippines, who were 7-30 years old, we determined the grade of hepatic fibrosis (HF) by ultrasound and used anthropometric measurements and hemoglobin levels to assess nutritional status. Serum levels of interleukin (IL)-1, IL-6, and IL-10; tumor-necrosis factor (TNF)-alpha; soluble TNF- alpha receptor I; and C-reactive protein (CRP) were measured to examine the association between these markers of inflammation and HF grade. HF was present in 8.9% of the cohort; the majority of cases were mild (grade I), and severe (grade II or grade III) cases occurred only in male individuals. Compared with individuals without HF, those with severe HF--and, to a lesser degree, those with mild HF--had a significantly lower body-mass index (BMI) and BMI z-score, a higher prevalence of anemia, and a higher level of CRP and were more likely to produce IL-6; furthermore, those with severe HF had a significantly higher level of IL-1, compared with those either without HF or with mild HF. These findings suggest that even mild HF is associated with nutritional morbidity and underscore the importance of early recognition and treatment. In addition, our data are consistent with the hypothesis that, by systemically increasing the levels of the proinflammatory cytokines IL-1 and IL-6, HF causes undernutrition and anemia.  相似文献   
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