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991.
992.
993.
The production of progesterone from pregnenolone, of cortisol from cortisone and of prostaglandin E (PGE) under basal and arachidonic acid-stimulated conditions was measured in cells dispersed from chorion and decidua. The cells were obtained after delivery from four groups of women: following spontaneous labour at term (38-42 weeks gestation), at elective caesarean section at term before the onset of labour, after induced labour at term, and after uncomplicated preterm (27-36 weeks) labour. Chorionic cells had a high progesterone output with relatively low cortisol and PGE production, whereas decidual cells had a high cortisol and PGE production rate. Free arachidonic acid stimulated PGE production in both decidual and chorionic cells. There were no significant differences in either steroid or PGE production among the four groups studied. These data suggest that steroid dehydrogenase activity in choriodecidual cells is not related to the mode of onset of labour and that the increased prostaglandin production in intrauterine tissues associated with parturition is due to enhanced availability of arachidonic acid.  相似文献   
994.
995.
996.
The performance of a tooth replacement by using a dental implant relies on the mechanical and biological capability of the anatomical substitute to restore lost physiological functions. The design of an implant device able to properly replace the physiological tooth requires the study of the load transfer mechanism at the implant-bone interface and the understanding of the relevance of the periodontal ligament (PDL) in this mechanism. The PDL is a connective soft tissue that provides the fixation of the tooth in its bone-socket and the attenuation of occlusal loads. It also provides the ground cells that are involved in the remodelling process, induced by a change in the stress-strain pattern of the alveolar bone and also in the cementum of the tooth root. The purpose of this study was to determine the PDL effects on the dynamic load transfer mechanism, from the tooth to the alveolar bone, evaluating the equivalent dynamic stiffness of the ligament structure. A porcine fresh mandible with a tooth was used within the study, applying an experimental procedure to identify the dynamic transmissibility of the entire system. The transmissibility function provided information about the stiffness and damping of the PDL, information that can assist the design of an improved dental implant system.  相似文献   
997.
Experience in the treatment of 129 patients with esophagogastric hemorrhage due to portal hypertension is discussed. An original modification of the design of Blakemore's tube is suggested, with the use of which the results of nonoperative treatment were improved and the mortality among this category of patients was reduced. Operation was performed on 75 patients. The total mortality among all hospitalized patients was 6.2%. The Tanner-Petrov operation was carried out on 55 patients, splenorenal anastomosis was formed in 6, organopexy was conducted on 4, splenectomy in combination with organopexy in 8, and portocaval anastomosis was formed in 2 patients. Three patients died after the operation.  相似文献   
998.
999.
Cognitive functions were investigated in 37 patients with myotonic dystrophy (MD) and correlated with clinical and neuroradiological variables. The whole cognitive performance was at a low-average level; in about 1/3 of the subjects, in fact, the scores at the neuropsychological tests were below the normal range. There was a consistent trend for patients with inheritance on maternal side to perform worse on Wechsler verbal score and to present cerebral atrophy. In 7 out of 12 subjects focal white matter lesions were found at nuclear magnetic resonance. The significance of these findings and its relation to cognitive performance are discussed.  相似文献   
1000.
Although there are well-established clinical human milk banks in the United States, there are no milk banks specifically intended to foster research on human milk. The authors' goal was to establish a milk bank with a core data set to support exploratory and hypothesis-driven studies on human milk. Donations to the Cincinnati Children's Research Human Milk Bank are accepted within the context of ongoing, hypothesis-driven research or on an ad hoc basis. Donors must give informed consent, and scientists wishing to use the samples must have Institutional review board approval for their use. Development of more research human milk banks can potentially provide resources for multidisciplinary collaboration and advance the study of human milk and lactation.  相似文献   
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