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891.
892.
893.
EK Pressman SM Zeidman UM Reddy JI Epstein H Brem 《Canadian Metallurgical Quarterly》1995,40(4):251-259
Lymphocytic adenohypophysitis (LAH) is an autoimmune disorder of the pituitary gland with a predilection for the peripartum period and often mimics a pituitary adenoma. We sought to define the clinical, endocrinologic and radiographic characteristics differentiating peripartum LAH from pituitary adenoma to enable the use of noninvasive diagnosis and appropriate therapy. From published reports and our own case, the clinical histories and laboratory and radiographic studies of 45 patients fulfilling the diagnosis of peripartum LAH were reviewed. History of infertility or menstrual irregularity, symptomatology, endocrinologic evaluation, diagnostic imaging and associated medical conditions were analyzed. For comparison, 806 patients with pituitary adenoma and pregnancy from published series were evaluated. The spontaneous pregnancy rate in pituitary adenoma patients was 2.4% vs. 100% in LAH patients. Visual disturbances and headaches were significantly more frequent in patients with LAH. Prolactin levels were significantly lower in patients with LAH than in those with pituitary adenomas (34.6 +/- 46.3 [SD] vs. 393.0 +/- 300.4, P < .0001). Abnormalities in thyroid and/or adrenal function were also more common in patients with LAH (57.5% vs. 2.5%, P < .001). There were no distinguishing characteristics on radiographic studies. History and endocrinologic evaluation can differentiate between LAH and pituitary adenoma in the peripartum patient. 相似文献
894.
895.
Five hearts with ruptured congenital sinus of Valsalva aneurysm were studied. In 3 hearts of Caucasian patients, the sinus of Valsalva aneurysms were located in the immediate vicinity of the commissure between the noncoronary and right aortic cusps with rupture from the noncoronary sinus to the right atrium (n = 2) and from the right sinus to the right ventricle (n = 1). In 2 hearts of indigenous North Americans, the defects were sited in the immediate vicinity of the commissure between right and left aortic cusps with rupture into the right ventricle; both patients had an associated conal septal hypoplasia ventricular septal defect and aortic insufficiency. The diameters of the rupture holes at the base of the sinus of Valsalva aneurysms in the five hearts ranged from 0.4 to 1.1 cm (mean 0.7 cm). Histologic examination of longitudinal sections through the ruptured sinus of Valsalva showed 0.8 to 1.7 cm (mean 1.1 cm) wide areas in which there was lack of continuity between the aortic media and the aortic annulus. Conclusions. This study shows that the site of congenital weakness in sinus of Valsalva aneurysm in indigenous North American patients may be similar to that in Oriental patients, whereas the site tends to be different in Occidental patients. It also emphasizes the importance of patch closure rather than suture closure of ruptured sinus of Valsalva aneurysms. 相似文献
896.
897.
The reaction of acetaldehyde with deoxynucleosides was studied in buffered solutions at room temperature (22-24 degrees C) and neutral pH. Reaction products were obtained with all deoxynucleosides with the exception of thymidine, as shown by reversed-phase HPLC analysis. The order of reactivity was dGuo > dAdo > dCyd, for which three, two and one reaction products, respectively, were obtained. We report here data on the kinetics of the reactions, the stability of the adducts at physiological pH, product yields, UV-spectroscopic data at different pH values, and describe the synthesis, isolation and structural characterization by FAB/MS and NMR of the stable adducts of acetaldehyde with dGuo. Furthermore, the formation of adducts with dGuo by the cooperative reaction of Aa with ethanol was studied. 相似文献
898.
899.
The specific size and retinal location of an object are readily perceived, yet recognition of an object's identity is hardly affected by transformations of its size or location. To explore how such stimulus transformations are treated by known mechanisms for visual short-term memory in inferior temporal (IT) cortex, IT cells were recorded in monkeys performing a delayed matching-to-sample task. The stimuli were pictures of complex objects, and the monkeys ignored differences in size and retinal location when matching the test items to the sample held in memory. The sensory information communicated by cells was assessed in their responses to the sample stimuli, and mnemonic information was assessed in their responses to the test stimuli. In the sensory domain, the ordering of relative stimulus preferences for nearly all cells was invariant over changes in size or location; however, some cells nonetheless preferred stimuli of a given size or location. In the mnemonic domain, the responses of many cells were modulated according to whether the test stimulus matched the sample held in memory, and these memory effects were invariant over the relative sizes and locations of the stimuli. Thus, IT neuronal populations may mediate not only the recognition and memory of object identity, which are invariant over size and location, but also the perception of the transformations themselves. 相似文献
900.
T.P. Nichols P. Leinster A.E. McIntyre J.N. Lester R. Perry 《The Science of the total environment》1981,19(3):285-292
An investigation of atmospheric quality in the vicinity of Heathrow airport (London) has been undertaken. Ambient concentrations of total hydrocarbons, methane, carbon monoxide, non-methane hydrocarbons and airbone particulate lead were monitored. Eight sites were visited in each of the years the survey was undertaken, approximately half of the sites were close to the airport perimenter and the remainder in the surrounding urban residential areas. This was achieved by the use of a mobile laboratory containing the necessary continuous monitors. Although the objective of the study was to assess the impact of the airport upon air quality, no distinction could be made between the relative contributions to air pollution of the airport sources and those arising from motor vehicle and industrial activity in the area. 相似文献