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101.
Pretreatment of recipients with the monoclonal antibody (MoAb) S5 facilitates engraftment of bone marrow from mismatched, unrelated donors in the canine transplantation model. In the direct comparisons reported here, the S5 glycoprotein (gp) was found to have structural homology to CD44 that in humans has been implicated in adhesive interactions of one type of effector cell, the lymphocyte. The S5 antigen and gp90Hermes-1 exhibited codistribution on canine peripheral blood cells. Both S5 and Hermes-1 (anti-CD44) MoAbs recognized 90-Kd species in radioimmune precipitations of 125I surface-labeled canine peripheral blood lymphocytes and bone marrow cells. Competitive antibody binding experiments showed that the epitope detected by S5 was distinct from that bound by Hermes-1 but overlapped with those defined by two other known anti-CD44 reagents, IM7 and Hutch-1. Sequential immunoprecipitation with S5 and Hermes-1 indicated that the two antibodies recognize the same or overlapping subsets of membrane gps. Tryptic digestion of S5 and anti-CD44 immunoprecipitates generated two major iodinated peptides of 27 and 35 Kd in both cases, a further indication of structural homology. Similarly, after N-glycanase digestion, S5 and CD44 immunoprecipitates were resolved to a single 68- Kd species. These findings suggest that CD44-mediated adhesive events may affect the fate of transplanted hematopoietic cells. The previous implications of this gp in T-lymphocyte activation and lymphocyte adhesion to endothelium thus provide useful paradigms to analyze its function in the bone marrow transplant setting. 相似文献
102.
103.
Pituitary adenomas: high-resolution MR imaging at 1.5 T 总被引:3,自引:0,他引:3
The magnetic resonance (MR) images of 28 patients with surgically confirmed pituitary adenomas were retrospectively evaluated. The examinations were performed on a 1.5-T superconducting MR system using a multisection spin-echo technique with 3-mm-thick sections and a 256 X 256 matrix. T1- and T2-weighted images were obtained in sagittal and coronal planes. The MR findings were correlated with detailed operative reports and diagrams. There were 11 microadenomas and 17 macroadenomas. Ten of the microadenomas and all of the macroadenomas were accurately localized and their extent delineated, particularly on T1-weighted coronal sections. Adenomas typically appeared hypointense on T1-weighted coronal sections. The appearance on T2-weighted images was variable, and generally the lesions were less well seen. Involvement of parasellar structures, particularly the optic chiasm and cavernous sinuses, was accurately depicted. Cyst formation and hemorrhage could be characterized in some instances. In general, there was excellent correlation between MR imaging and operative findings. 相似文献
104.
105.
Ultrasonographic (US) findings were correlated with clinical outcome in seven cases of meconium peritonitis detected with prenatal US during a 2-year period. Nineteen previously reported cases were also reviewed. US findings included intraabdominal calcifications (n = six cases), fetal ascites (n = 3), echogenic ascites without calcifications (n = 1), bowel dilatation (n = 2), and polyhydramnios (n = 5). Following delivery, six infants were still alive after a mean follow-up of 13 months (range, 6-26 months); the seventh died of hydrocephalus. Of the six, four required surgical correction of a small-bowel perforation and two did not. All six are thriving, and none has yet been found to have cystic fibrosis. In the 19 previously reported cases, there were only two cases of cystic fibrosis, neither with intraabdominal calcifications. The presence of calcifications was significantly associated with causes other than cystic fibrosis. Prenatally diagnosed cases of meconium peritonitis are associated with cystic fibrosis less frequently than previous studies suggest. 相似文献
106.
Rathke cleft cysts: CT, MR imaging, and pathologic features 总被引:1,自引:0,他引:1
The authors retrospectively reviewed the clinical, computed tomography (CT), and magnetic resonance (MR) imaging findings in seven patients with pathologically proved Rathke cleft cysts. All the cysts were located in the anterior sella turcica or the anterior suprasellar cistern. Five cysts had both intra- and suprasellar components, one was entirely intrasellar, and the other was predominantly suprasellar in location. The size of the cysts ranged from 8 to 20 mm. CT scans demonstrated low-density homogeneous lesions in four cases. On MR images of three of these four cases, the cysts had the same intensity as cerebrospinal fluid on T1- and T2-weighted images, while in the fourth case, the cyst was hyperintense on the T1-weighted images. In the remaining three cases, CT showed slight hyperdensity relative to brain parenchyma, suggestive of contrast enhancement. MR showed signal heterogeneity of these lesions with focal components of diminished signal intensity of T2-weighted images. These same foci appeared iso- to slightly hyperintense on T1-weighted images. 相似文献
107.
吡啶单萜烯isocantleyine的结构测定 总被引:2,自引:0,他引:2
自玄参科植物阴行草(Siphonostegia chinensis Benth)的地上部分分得一吡啶单萜烯类新生物碱,经物理常数测定和光谱(UV,IR,MS,1HNMR,2D-NMR,13CNMR)分析,确定其结构为5H-pyridine-4-carboxylic acid,6,7-dihydro-6-hydroxy-7-methyl-methyl ester,定名为isocantleyine。此外,尚分得一已知内酯类成分loliolide,也是首次自本植物中得到。 相似文献
108.
109.
Martijn van der Eijk Marjan J Faber Johanna WM Aarts Jan AM Kremer Marten Munneke Bastiaan R Bloem 《Journal of medical Internet research》2013,15(6)