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This study was undertaken to compare the fixation of the semitubular blade plate with that of the AO T plate. Cadaveric humeri (n=12 pairs) from an elderly population (41 to 89 years) had either a blade plate (n=12) or a T plate (n=12) fixed to them, subsequent to which a transverse osteotomy was performed. Mechanical testing in tension was performed in 1 series (n=5, blade plate; n=5, T plate) by applying a single maximal load to failure and in a second series (n=7, blade plate; n=7, T plate) by applying submaximal cyclic loading before failure was induced. Results showed that the fixation provided by the semitubular blade plate was significantly better (P < .05) than that of the T plate in those specimens subjected to submaximal cyclic loading before failure (series 2). This latter testing method contains some component of the clinical situation compared with monotonic distraction to failure. Based on these results plus favorable clinical results reported in the literature, the semitubular blade plate is possibly a better alternative to the T plate in the management of proximal humeral fractures that require open reduction and internal fixation.  相似文献   
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The finding of heat-stable enzymes or the engineering of moderately thermostable enzymes into more stable ones by random or site-directed mutagenesis has become a main priority of modern biotechnology. We report here for the first time a heat-stable phytase able to withstand temperatures up to 100 degrees C over a period of 20 min, with a loss of only 10% of the initial enzymatic activity. The gene (phyA) encoding this heat-stable enzyme has been cloned from Aspergillus fumigatus and overexpressed in Aspergillus niger. The enzyme showed high activity with 4-nitrophenyl phosphate at a pH range of 3 to 5 and with phytic acid at a pH range of 2.5 to 7.5.  相似文献   
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Compliance of the lungs and thorax was studied in 65 pregnant women during cesarean section. The measurements were carried out in a group of healthy controls and in patients with preeclampsia. The detected changes indicated increased rigidity of the lungs even in normal pregnancy. Comparison of the results indicates an appreciable increase of rigidity of the lungs in patients with preeclampsia, this permitting us to regard it as a status involving interstitial pulmonary hyperhydration.  相似文献   
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Forty-five cases of gastroschisis and 85 of omphalocele were reviewed. The survival of gastroschisis has dramatically improved over the past 20 years, however, that of omphalocele still remained in the lower value, because the size of the defect and the presence of associated anomalies are prognostic factors. The primary fascial closure was first employed for the patients with gastroschisis and a silo chimney was used for limited cases. On the other hand, for the patients with omphalocele, primary closure was possible in 34 cases, silo chimney was used in 17, and 45 cases had nonoperative management with epithelialization. Among them, nonoperative management using painting was the most reliable therapeutic for omphalocele.  相似文献   
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