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61.
62.
Mario DeMarchi Iolanda Borelli Eleonora Olivetti Patricia Richiardi Pamela Wright Nicoletta Ansaldi Cristiana Barbera Bruna Santini 《Tissue antigens》1979,14(4):309-316
A group of 45 children affected with Coeliac Disease (CD) was typed for HLA-A, B, C, D, and DR specificities. The most significant associations were found with two alleles of the D series, with both cellular and serological typing. It is suggested that the susceptibility to CD is determined by two different genes within the HLA region, the first in common with organ-specific autoimmune diseases and associated with DW3, the second possibly specific for CD and associated with Dw7. 相似文献
63.
When isolated from their dams and littermates, rat pups emit ultrasonic vocalizations to elicit attention and retrieval from their dams. This study examined the effects of perinatal alcohol exposure on ultrasonic vocalizations and maternal-infant interactions. Alcohol was administered throughout gestation to the dams and during the early postnatal period to the pups. Control groups consisted of a nontreated control and an intubated, pair-fed control. Ultrasonic vocalizations were measured on postnatal day (PD) 5 under varying conditions of isolation. Maternal behaviors were examined on PD2, 4, 6, 8, and 10. Maternal behaviors were not significantly affected by prior alcohol administration to either the dams or the pups. However, ethanol-exposed rat pups vocalized more on PD5 than controls regardless of condition. The heightened vocalization response of the ethanol-exposed pups might be an underlying factor in the persistent effects of perinatal ethanol exposure on social behavior. 相似文献
64.
Ines K. Lauva Eric Brody Eric Tiger Robert L. Kent George Cooper Thomas A. Marino 《Developmental dynamics》1986,177(1):71-80
Previous studies have demonstrated that there is a disproportionate increase in connective tissue in right ventricular myocardium subjected to pressure-overload hypertrophy associated with depressed cardiac contractility. While the myocardium is primarily responsive to load, the aim of the present study was to determine whether catecholamines also modulate the response of myocardial tissue components and cardiocyte organelles in pressure-overload-induced cardiac hypertrophy. Four experimental groups of cats were examined: (1) a sham-operated control group, (2) a group which had their pulmonary arteries banded in order to induce a pressure overload, (3) a group which had been subjected to the same pressure overload, but in addition had β-adrenoceptor blockade produced prior to and during the pressure overloading, and (4) a group which had been subjected to the same pressure overload, but in addition had α-adrenoceptor blockade produced prior to and maintained during the pressure overloading. As in our previous study, there was a significant and equivalent degree of right ventricular hypertrophy in all experimental groups with pressure overload when assessed either as the ratio of right ventricular weight to body weight or as cardiocyte cross-sectional area. At the light microscopic level, the disproportionate increase in the volume density of myocardial connective tissue seen in banded animals was completely prevented by either α- or β-adrenoceptor blockade. At the electron microscopic level, there was a reduction in the mitochondrial and myofibrillar volume fractions following β-adrenoceptor blockade. The results of this study provide evidence for a modulatory role of catecholamines in the control of myocardial connective-tissue proliferation in pressure-overload-induced cardiac hypertrophy. There is also evidence to support the role of the adrenergic nervous system in regulating cardiocyte subcellular organelles, independent of the regulation of cardiocyte size. 相似文献
65.
Thomas A. Marino 《Developmental dynamics》1979,154(3):365-391
The cells of the atrioventricular (AV) junction in the ferret heart were examined using light microscopy, a wax-model reconstruction and quantitative electron microscopy to determine their organization and characteristics. A series of subdivisions of the specialized tissues of the AV junction was apparent at both the light and electron microscopic levels. A transitional zone was observed interposed between the atrial muscle cells and the AV node. The AV node consisted of a coronary sinus portion, a superficial portion and a deep portion. The AV bundle had a segment above the anulus fibrosus, a segment which penetrated the right fibrous trigone, a non-branching segment below the anulus fibrosus and a branched segment. At the ultrastructural level the AV junctional conduction tissues had fewer irregularly oriented myofibrils than did working atrial myocardial cells. T-tubules, present in atrial muscle cells, were not observed in the modified muscle cells of the AV node and bundle. Conventional intercalated discs also were not observed between the cells of the AV node or the AV bundle. Atrial myocardial cells had the highest percentage of the plasma membrane occupied by desmosomes, fasciae adherentes and gap junctions. The AV bundle cells had the highest percentage of appositional surface membrane and a relatively large fraction of plasma membrane occupied by gap junctions. Cells of the superficial portion of the AV node had the smallest percentage of the plasma membrane composed of gap junctions, desmosomes or fasciae adherentes, as well as the smallest fraction of the cell membrane apposed to adjacent cells. The stereological data indicate that the most useful distinguishing characteristic between atrial muscle cells and conduction cells was that a smaller percentage of the conduction cell sarcoplasm was occupied by mitochondria and myofibrils. The most useful characteristics that could be used to differentiate between the regions of the AV junctional conduction tissues were the amounts and types of surface membrane specializations in the respective cell types. 相似文献
66.
Hypoxia promotes murine bone-marrow-derived stromal cell migration and tube formation 总被引:13,自引:0,他引:13
Annabi B Lee YT Turcotte S Naud E Desrosiers RR Champagne M Eliopoulos N Galipeau J Béliveau R 《Stem cells (Dayton, Ohio)》2003,21(3):337-347
Recent evidence indicates that bone-marrow-derived stromal cells (MSCs) have a histology coherent with endothelial cells that may enable them to contribute to tumor angiogenesis through yet undefined mechanisms. In this work, we investigated the angiogenic properties of murine MSCs involved in extracellular matrix degradation and in neovascularization that could take place in a hypoxic environment such as that encountered in tumor masses. MSCs were cultured in normoxia (95% air and 5% CO(2)) or in hypoxia (1% oxygen, 5% CO(2), and 94% nitrogen). We found that hypoxic culture conditions rapidly induced MSC migration and three-dimensional capillary-like structure formation on Matrigel. In vitro, MSC migration was induced by growth-factor- and cytokine-enriched conditioned media isolated from U-87 glioma cells as well as from MSCs cultured in hypoxic conditions, suggesting both paracrine and autocrine regulatory mechanisms. Although greater vascular endothelial growth factor levels were secreted by MSCs in hypoxic conditions, this growth factor alone could not explain their greater migration. Interestingly, matrix metalloproteinase (MMP)-2 mRNA expression and protein secretion were downregulated, while those of membrane-type (MT)1-MMP were strongly induced by hypoxia. Functional inhibition of MT1-MMP by a blocking antibody strongly suppressed MSC ability to migrate and generate capillary-like structures. Collectively, these data suggest that MSCs may have the capacity to participate in tumor angiogenesis through regulation of their angiogenic properties under an atmosphere of low oxygen that closely approximates the tumor microenvironment. 相似文献
67.
Dougherty Sean Lorenzoni Luca Marino Alberto Murtin Fabrice 《The European journal of health economics》2022,23(4):705-715
The European Journal of Health Economics - This paper examines the role of institutions—notably the degree of administrative decentralisation across levels of government—in health care... 相似文献
68.
Santoro Giorgio Piccirilli Manolo Chiarella Vito Greco Nicoletta Berra Luigi Valentino Santoro Antonio 《Neurosurgical review》2021,44(4):1977-1985
Neurosurgical Review - Capillary hemangiomas (CHs) of the central nervous system represent a rare diagnosed pathology. CHs are benign vascular tumors whose most common manifestations are dermal and... 相似文献
69.
We compared the effects of continuous Ringer's lactate infusion and Ringer's lactate instillation on postsurgical adhesion formation in the rat model. The results show that intraperitoneal Ringer's lactate instillation reduces postsurgical adhesions. However, its efficacy is not improved by additional infusion of Ringer's lactate. 相似文献
70.
Among 20 known cytokeratins, cytokeratin fragment 19 is a 40 kD acidic molecule whose distibution is restricted to simple or pseudo-stratified epitelia, such as the epithelial layer of the bronchial tree. An immunoradiometric assay, CYFRA 21-1, was used to detect a fragment of cytokeratin 19 in the serum of 90 subjects and compared with serum levels of CEA, NSE and TPA. Sixty-seven consecutive patients with lung cancer and 23 healthy subjects were tested. Cut-off values for tumor markers were considered as the 95% of specificity versus controls. There were 32 adenocarcinomas, 29 squamous carcinomas and 6 other tumors. Increased serum levels of CYFRA 21-1 were found in lung cancer patients compared to controls [1.6 (0.2-3.2) versus 0.5 (0.2-1.8): p<0.001]. In our study TPA was more sensitive than CYFRA 21-1: 49% versus 40%; when we combined both markers the sensitivity increased to 63%. Significant difference in values were found before and after surgery in serum levels of 34 operated patients: p<0.01. We found higher levels of soluble cytokeratin 19 in lung cancer patients and in the adenocarcinoma subgroup. This study does not support the exclusive use of soluble cytokeratin 19 as a specific marker of lung cancer and not only in squamous carcinoma subgroup. This suggested that diagnostic and prognostic sensitivity increase when CYFRA 21-1 and TPA or other markers are combined. 相似文献