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71.
Total ovarian, luteal and stromal blood flows were measured with radioactive microspheres (25 mum diameter) in 7 rabbits anaesthetized with sodium pentobarbitone and 23 conscious rabbits at Day 28 of gestation. Despite major differences in cardiac output, arterial PO2, PCO2, pH and base status, ovarian tissue blood flows were similar in both groups. In the conscious rabbits total ovarian blood flow was negatively related to arterial pressure, and luteal blood flow was negatively related to pressure and arterial pH. In the anaesthetized rabbits ovarian stromal blood flow was positively related to arterial PO2. 相似文献
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AIMS: A surgical technique has been developed in order to obtain ocular alignment in the primary position in patients with third nerve palsy. METHODS: A method for surgically correcting the vertical deviation and the pseudoptosis is described in three patients with longstanding third nerve palsy. By decreasing the ability of the non-involved eye to elevate, a fixation duress was created which eliminated the secondary deviation that characteristically occurs in such patients when the involved eye fixates. As a result of this technique, both eyes in all patients on attempted fixation were under similar duress, therefore requiring equal amounts of stimulation to move into the primary position. When the fixation duress was sufficient, elimination of the hypotropia and ptosis was achieved. Additionally, in order to correct the exotropia, generous recession and resection procedures in the involved eye and recession of the lateral rectus in the noninvolved eye were performed. RESULTS: Between 8 and 10 prism dioptres of esotropia were achieved and maintained in two patients. One patient had 20 prism dioptres of exotropia. Two patients had no residual ptosis and one required an additional anterior levator resection to achieve a satisfactory result. CONCLUSION: Patients with a third nerve palsy and a pseudoptosis may be candidates for this approach. 相似文献
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JD Loike J el Khoury L Cao CP Richards H Rascoff JT Mandeville FR Maxfield SC Silverstein 《Canadian Metallurgical Quarterly》1995,181(5):1763-1772
We have examined the capacity of four different chemoattractants/cytokines to promote directed migration of polymorphonuclear leukocytes (PMN) through three-dimensional gels composed of extracellular matrix proteins. About 20% of PMN migrated through fibrin gels and plasma clots in response to a gradient of interleukin 8 (IL-8) or leukotriene B4 (LTB4). In contrast, < 0.3% of PMN migrated through fibrin gels in response to a gradient of tumor necrosis factor alpha (TNF) or formyl-methionyl-leucyl-phenylalanine (FMLP). All four chemoattractants stimulated PMN to migrate through gels composed of collagen IV or of basement membrane proteins (Matrigel), or through filters to which fibronectin or fibrinogen had been adsorbed. PMN stimulated with TNF or FMLP adhered and formed zones of close apposition to fibrin, as measured by the exclusion of a 10-kD rhodamine-polyethylene glycol probe from the contact zones between PMN and the underlying fibrin gel. By this measure, IL-8- or LTB4-treated PMN adhered loosely to fibrin, since 10 kD rhodamine-polyethylene glycol permeated into the contact zones between these cells and the underlying fibrin gel. PMN stimulated with FMLP and IL-8, or FMLP and LTB4, exhibited very little migration through fibrin gels, and three times as many of these cells excluded 10 kD rhodamine-polyethylene glycol from their zones of contact with fibrin as PMN stimulated with IL-8 or LTB4 alone. These results show that PMN chemotaxis is regulated by both the nature of the chemoattractant and the composition of the extracellular matrix; they suggest that certain combinations of chemoattractants and matrix proteins may limit leukocyte movements and promote their localization in specific tissues in vivo. 相似文献
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Microsporidia, as a group, cause a wide range of infections, though two species of microsporidia in particular, Enterocytozoon bieneusi and Encephalitozoon intestinalis, are associated with gastrointestinal disease in humans. To date, the mode of transmission and environmental occurrence of microsporidia have not been elucidated due to lack of sensitive and specific screening methods. The present study was undertaken with recently developed methods to screen several significant water sources. Water concentrates were subjected to community DNA extraction followed by microsporidium-specific PCR amplification, PCR sequencing, and database homology comparison. A total of 14 water concentrates were screened; 7 of these contained human-pathogenic microsporidia. The presence of Encephalitozoon intestinalis was confirmed in tertiary sewage effluent, surface water, and groundwater; the presence of Enterocytozoon bieneusi was confirmed in surface water; and the presence of Vittaforma corneae was confirmed in tertiary effluent. Thus, this study represents the first confirmation, to the species level, of human-pathogenic microsporidia in water, indicating that these human-pathogenic microsporidia may be waterborne pathogens. 相似文献