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. Neutrophil-mediated tissue damage has been implicated in the pathogenesis of diarrhoea-associated haemolytic uraemic syndrome (D+ HUS). This study evaluates priming and activation of the neutrophil oxidative burst in D+ HUS using chemiluminescent techniques. Peripheral blood neutrophils from 11 children with acute D+ HUS were examined. No difference was found in the oxidative burst of neutrophils from patients and controls. Serum elastase levels were measured in 8 patients and found to be significantly elevated. Although elastase results suggest neutrophil activation, chemiluminescence studies do not confirm this in the peripheral blood neutrophil. This does not support a significant role for circulating agents in priming and activating the peripheral blood neutrophil. Received August 17, 1995; received in revised form and accepted November 27, 1995  相似文献   
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OBJECTIVE: Conventional surgical management of prolapsing haemorrhoids is by excisional haemorrhoidectomy. Postoperative pain has restricted the application of such procedures in the day case setting. These operations remain associated with a period of restricted activity. The use of circular stapling devices as an alternative to the excisional approach in the management of haemorrhoids has been described. This study reports our experience of stapled haemorrhoidopexy as a day case procedure. METHODS: Patients with third or fourth degree haemorrhoids were eligible for the procedure. Patients were considered suitable candidates for day case surgery based on conventional parameters. Symptoms were assessed using a previously validated symptom severity rating score. Stapled haemorrhoidopexy was carried out using a circular stapling device. Pain scores were obtained prior to discharge. Patients were admitted if pain was uncontrolled despite oral analgesia. Symptoms were re-scored at six-week follow-up. RESULTS: Over a 70-month period 168 consecutive stapled haemorrhoidopexies were performed or directly supervised by one consultant colorectal surgeon. One hundred and ten (65%) patients were considered appropriate candidates for day case surgery by conventional criteria. Ninety-six (87.3%) patients successfully underwent stapled haemorrhoidopexy on a day case basis. Fourteen (12.7%) patients required admission on the day of surgery (5 for early postoperative bleeding, 4 for pain necessitating continuing opiate analgesia, two for urinary retention and three for surgery performed late in the day). Six (5%) patients were re-admitted postoperatively; four for pain relief and two because of urinary retention. Of the day case patients, 91 (82.7%) and 56 (50.9%) had been seen for 6 week and 6 month review, respectively, at the time of analysis. Symptom scores were 6 (pre-operatively) vs 0 (postoperatively) (P < 0.01). 76/91 (83.5%) patients reviewed at 6/52 were asymptomatic. CONCLUSION: Stapled haemorrhoidopexy is a safe and effective procedure that can be carried out on selected patients on a day case basis. Complications are of a similar nature to excisional haemorrhoidectomy.  相似文献   
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The frequency of hydatid disease in Iraq is as follows: (a) Man 1 in 319, hospital in-patients. (b) Dog 17.83 per cent. (c) Sheep and goats 11.93 per cent. (d) Cattle 24.66 per cent.  相似文献   
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OBJECTIVES: 1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups. METHODS: Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion. RESULTS: Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects. CONCLUSION: The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities.  相似文献   
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O6-Alkylguanine--DNA alkyltransferase (AGT) is a protein which removes the promutagenic O6-alkylguanine lesion induced in DNA by alkylating agents. Our results demonstrate that freshly isolated organoids from reduction mammoplasty specimens contain significant levels of AGT activity. AGT activity in breast epithelial cells shows interindividual variation. Constitutive levels of AGT activity remain unchanged during short-term serum-free culture of breast epithelial cells inside three-dimensional rat-tail collagen gel matrix. In the present study, we optimized conditions for depleting AGT activity in human breast epithelial cells cultured in three-dimensional collagen gel matrix using O6-methylguanine and O6-benzylguanine which are substrates for AGT. AGT activity was efficiently inactivated by exposure of cells to O6-methylguanine or O6-benzylguanine. Inactivation with O6-benzylguanine was more rapid, of greater magnitude and consistency and occurred at lower concentrations than with O6-methylguanine. Near-complete inactivation (> 99.5%) of AGT activity was reproducibly achieved with 50 microM O6-benzylguanine. In contrast, 500 microM O6-methylguanine was needed to obtain a maximal effect and this reduced AGT activity by only 53-93% of control. Within 30 min of adding the free base, 50 microM O6-benzylguanine depleted 95% of the levels of AGT compared to 30% inhibition with 500 microM O6-methylguanine. The profile for restoration of AGT activity was different following a 24 h incubation and subsequent removal of each of the guanine derivatives. AGT activity levels remained undetectable for at least 2 days after removal of 50 microM O6-benzylguanine from the medium and recovered to only 53% of control values after an additional 3 days. AGT activity levels remained undetectable for at least 2 days after removal of 50 microM O6-benzylguanine from the medium and recovered to only 53% of control values after an additional 3 days. In contrast, following removal of 500 microM O6-methylguanine, the activity was restored from its nadir of 16% of control values reaching pretreatment levels after 5 days. These results suggest that treatment with O6-benzylguanine may be used to modulate the incidence of transforming mutations in cultured human breast epithelial cells treated with chemical carcinogens which give rise to O6-alkylguanine adducts.  相似文献   
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