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41.
Detection of renal cell carcinoma (RCC) is increasing with the greater use of cross‐sectional imaging and up to two‐thirds of RCCs are discovered incidentally in asymptomatic patients. The traditional option of nephrectomy or partial nephrectomy may not always be appropriate. A minimally invasive treatment alternative is radiofrequency ablation (RFA). We retrospectively reviewed the RFA cases for renal tumours at our institution between January 2004 and June 2006. Thirteen RFA treatment sessions were conducted for 11 neoplasms in 11 patients. Mean patient age was 74.4 years (61–88 years). Imaging was carried out after ablation with a mean follow up of 8.0 months (2–26 months). No residual tumour was observed after the first RFA treatment in 82% of patients (nine of 11). Two patients required a second RFA treatment for residual (one) or recurrent tumour (one). RFA is emerging as a useful technique for treatment of small renal tumour. A number of short‐term studies reflect this, however, long‐term findings are still lacking.  相似文献   
42.

Background  

Chronic obstructive pulmonary disease (COPD) is a major but neglected public health problem. Currently 1.4% of the England population has a clinical diagnosis of COPD, but the true burden of the disease has not been known with certainty, as many cases remain undiagnosed.  相似文献   
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PURPOSE: To assess the frequency and pathogenesis of hyperkalemia in the very low birth weight infant. METHODS: Infants who weighed less than 1000 gm at birth were prospectively entered into the study within 12 hours of birth. Potential risk factors for hyperkalemia were assessed. Body weight, fluid and electrolyte balance, serum levels of sodium and potassium, creatinine clearance, fractional sodium excretion, and urine sodium/potassium ratio were measured every 8 hours for 72 hours. Measurements of plasma renin, serum aldosterone, and plasma atrial natriuretic factor were made at study entry and repeated when hyperkalemia (serum potassium greater than 6.5 mmol/L) occurred or at 72 hours. Infants in whom hyperkalemia developed were compared with those in whom it did not. RESULTS: Thirty-one infants completed the study; hyperkalemia developed in 16 (51.6%). The only difference in the occurrence of perinatal complications was the more frequent occurrence of pH less than 7.20 in infants with subsequent development of hyperkalemia. Creatinine clearance, urine output, and potassium excretion were significantly lower in the hyperkalemia group during the first 24 hours. Serum potassium concentration at 24 hours was inversely related to urine output in the prior 24 hours. Fractional sodium excretion, urine sodium/potassium ratio, and levels of renin, aldosterone, and atrial natriuretic factor did not differ between groups. CONCLUSIONS: Hyperkalemia is a frequent complication in very low birth weight infants. Infants with low urinary flow rates during the first few hours after birth are at greatest risk for the development of hyperkalemia.  相似文献   
45.
Because bacterial colonization of medical devices may result in clinical infection, it is conceivable that antimicrobial impregnation of tissue expanders may reduce the rate of infection. The objective of this in vitro study was to examine the spectrum, durability, and shelf-life antimicrobial activity of minocycline/rifampin-impregnated silicone tissue expander shells. The impregnated devices exhibited zones of inhibition at baseline against Staphylococcus epidermidis, Staphylococcus aureus, and Escherichia coli. The impregnated devices exhibited strong residual activity against S. epidermidis and S. aureus after suspension in serum at 37 degrees C for 4 weeks. There was no significant decrease in the size of zones of inhibition after storing the impregnated devices at room temperature for 1 year. These results indicate that minocycline/rifampin-impregnated tissue expander shells provide broad-spectrum and durable antimicrobial activity and that the shelf-life antimicrobial activity exceeds 1 year. These findings prompt future exploration of the anti-infective efficacy of these antimicrobial-impregnated devices.  相似文献   
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The HMC-1 mast cell line has both adenosine A(3) and A(2b) receptors on its surface, but only agonists of the A(2b) receptor are effective at releasing interleukin 8. Object of this study was to look for co-factors for adenosine A(2b) receptor activation. There was a powerful and statistically significant synergy for release of IL-8, both at the mRNA level (measured after 4 hr) and protein level (measured after 24 hr), between adenosine A(2b) receptor agonists and stem cell factor (SCF). Suitable concentrations for showing synergy were 100 ng/mL SCF and 3 microM 5'-N-ethylcarboxamidoadenosine (NECA). At these concentrations, the IL-8 released into the culture medium after SCF and NECA together was typically 3-5-fold greater in amount than the sum of the amounts of IL-8 released after exposure to the same concentrations of NECA and SCF separately. Since mast cells may be exposed to both adenosine and stem cell factor in the diseased lung, the synergy observed in this model system may have implications for asthma.  相似文献   
48.
Meade T 《Lancet》2003,362(9382):492
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Summary: The case notes of women with singleton term (37 weeks' gestation and beyond) breech presentation and delivery were retrospectively reviewed. Thirty-two of the 72 women in the study group had attempted external cephalic version at term, with a success rate of 53% (17 women). The Caesarean section rate was significantly lower in the group which had attempted ECV compared to the group which did not.  相似文献   
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