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This investigation has been conducted as two separate studies. Part I consisted of the determination of the prothrombin activity in normal newborn infants together with observations on the alterations in this activity which result from the administration of vitamin K to the mother. Part II was concerned with the practical application of the knowledge gained from the first study. It aimed to show the value of intra-partum vitamin K administration in reducing the incidence of hemorrhage in newborn infants.  相似文献   
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Purpose Assessment of tumor proliferation rate using Bromodeoxyuridine labeling index (BrdUrdLI) as a possible predictor of rectal cancer response to preoperative radiotherapy (RT). Methods and material Ninety-two patients were qualified either to short RT (5 Gy/fraction/5 days) and surgery about 1 week after RT (schedule I), or to short RT and 4–5 weeks interval before surgery (schedule II). Tumor samples were taken twice from each patient: before RT and at the time of surgery. The samples were incubated with BrdUrd for 1 h at 37°C, and the BrdUrdLI was calculated as a percentage of BrdUrd-labeled cells. Results Thirty-eight patients were treated according to schedule I and 54 patients according to schedule II. Mean BrdUrdLI before RT was 8.5% and its value did not differ between the patients in the two compared groups. After RT tumors showed statistically significant growth inhibition (reduction of BrdUrdLI). As the pretreatment BrdUrd LI was not predictive for early clinical and pathologic tumor response, prognostic role of the ratio of BrdUrdLI after to BrdUrdLI before RT was considered. The ratios were calculated separately for fast (BrdUrd LI > 8.5%) and slowly (BrdUrd LI ≤ 8.5%) proliferating tumors and correlated with overall treatment time (OTT, i.e., time from the first day of RT to surgery). One month after RT, accelerated proliferation was observed only in slowly proliferating tumors. Conclusions Pretreatment BrdUrdLI was not predictive for early clinical and pathologic tumor response. The ratio after/before RT BrdUrdLI was correlated to inhibition of proliferation in responsive tumors. The paper was presented at ECCO 13, October 30 to November 03, 2005 in Paris, France  相似文献   
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Objective Gallstone bacteria provide a reservoir for biliary infections. Slime production facilitates adherence, whereas β-glucuronidase and phospholipase generate colonization surface. These factors facilitate gallstone formation, but their influence on infection severity is unknown. Methods Two hundred ninety-two patients were studied. Gallstones, bile, and blood (as applicable) were cultured. Bacteria were tested for β-glucuronidase/phospholipase production and quantitative slime production. Infection severity was correlated with bacterial factors. Results Bacteria were present in 43% of cases, 13% with bacteremia. Severe infections correlated directly with β-glucuronidase/phospholipase (55% with vs 13% without, P < 0.0001), but inversely with slime production (55 vs 8%, slime <75 or >75, P = 0.008). Low slime production and β-glucuronidase/phospholipase production were additive: Severe infections were present in 76% with both, but 10% with either or none (P < 0.0001). β-Glucuronidase/phospholipase production facilitated bactibilia (86% with vs 62% without, P = 0.03). Slime production was 19 (±8) vs 50 (±10) for bacteria that did or did not cause bacteremia (P = 0.004). No bacteria with slime >75 demonstrated bacteremia. Conclusions Bacteria-laden gallstones are biofilms whose characteristics influence illness severity. Factors creating colonization surface (β-glucuronidase/phospholipase) facilitated bacteremia and severe infections; but abundant slime production, while facilitating colonization, inhibited detachment and cholangiovenous reflux. This shows how properties of the gallstone biofilm determine the severity of the associated illness. Presented at the annual meeting of the Society for Surgery of the Alimentary Tract, held May 20–24, 2006 in Los Angeles, California.  相似文献   
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Screening for osteoporotic vertebral fractures traditionally involves X-ray of the thoracic and lumbar spine. We evaluated use of dual energy X-ray technology in patients with osteoporosis. We found this technology useful in the clinic setting and it has advantages in that less radiation is delivered to the patient.  相似文献   
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