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61.
Seymour Furman 《Pacing and clinical electrophysiology : PACE》1992,15(9):1356-1356
62.
Tumors from 40 patients and 7 established human xenograft tumor lines were grown in three-dimensional histoculture. A Viable-Cell-Index (VCI) based on fluorescent dyes and Growth Fraction Index (GFI) based on [3H]thymidine incorporation were measured by confocal microscopy and histological autoradiography, respectively, after treatment with cytotoxic agents. Chemosensitivity in vitro with the two methods was correlated with chemosensitivity of the same set of human xenografted tumor lines grown in nude mice. The percent accuracy of in vitro to in vivo correlation with VCI (73%) was higher than GFI (63%). The number of false positives with VCI was 12.1% (4/33), and with GFI was 31.3% (10/32). The results thus indicated that in vitro histoculture with fluorescent vital-dye end-points to measure cell viability is of potential use to determine tumor chemosensitivity. 相似文献
63.
Seventy-nine patients with advanced breast cancer were tested for the presence, in serum, of a 110 kDa soluble, c-erbB-2 fragment. Thirty-nine patients were seropositive. There was no correlation between seropositivity and menopausal status, or with oestrogen status. In addition, no correlation could be found between tissue c-erbB-2 immunostaining for the external domain of the c-erbB-2 receptor and the presence of soluble c-erbB-2 in serum. The presence of serum soluble c-erbB-2, however, had a significant impact on survival of patients with advanced disease, suggesting that this test may become a useful independent prognostic indicator. 相似文献
64.
R. A. Gardiner M. L. T. H. Samaratunga M. D. Walsh G. J. Seymour M. F. Lavin 《Urological research》1992,20(2):117-120
Summary Sections of formalin-fixed, paraffin-blocked tissue from 116 primary transitional cell carcinomas were stained immunohistochemically using a polyclonal antibody against the c-erbB-2 oncoprotein. Positive staining of cell membranes, known to correlate with gene amplification, was seen in 22 (19%) of the 116, with variable staining from tumour to tumour and within tumours themselves. Consistent with its mooted value as a prognosticator in bladder cancer, the c-erbB-2 oncoprotein was detected in 13 (of 40) grade III and 9 of the 26 muscle-invasive tumours examined compared to 1 (of 25) grade I and 6 (of 66) mucosa only (pTa) lesions. These results support further examination of c-erbB-2 expression in bladder cancer. 相似文献
65.
Use of the abdominal aorta for arterial input function determination in hepatic and renal PET studies. 总被引:2,自引:0,他引:2
G Germano B C Chen S C Huang S S Gambhir E J Hoffman M E Phelps 《Journal of nuclear medicine》1992,33(4):613-620
A method using the activity in the abdominal aorta of human and animal subjects to noninvasively estimate blood-pool input function in dynamic, abdominal PET scans is proposed and validated in this paper. Partial volume effects due to the aorta's dimensions are corrected by a semi-automated algorithm based on the transaxial resolution in the reconstructed images. The technique was validated by comparing PET measurements of abdominal aortic activity to well counter measurements of arterial blood samples (eight canine renal studies) and to PET measurements of left ventricular cavity activity (eight human hepatic studies). In renal studies, correlation analysis of the areas subtended by the two input functions yielded an essentially unitary slope (1.03 +/- 0.09), with high correlation (R2 greater than 0.95, p less than 0.001). In hepatic studies, similar values (0.99 +/- 0.03 and R2 greater than 0.85, p less than 0.001) were found. Correlation of the blood flow estimates based on the two input functions and a two-compartment model produced slopes of 1.07 +/- 0.16 and 1.03 +/- 0.07, and correlations of (R2 greater than 0.98, p less than 0.001) and (R2 greater than 0.97, p less than 0.001) for the renal and hepatic studies, respectively. We conclude that noninvasive, accurate measurements of the arterial input function by dynamic PET imaging are possible and represent a clinically viable alternative to arterial blood sampling. 相似文献
66.
Leukocyte chemoattraction by 1,2-diacylglycerol. 总被引:3,自引:0,他引:3
T M Wright R D Hoffman J Nishijima L Jakoi R Snyderman H S Shin 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(6):1869-1873
Previous reports have demonstrated the hydrolysis of inositol phospholipids in polymorphonuclear leukocytes (PMN) in response to chemoattractants and in lymphocytes in response to the mitogen phytohemagglutinin. We investigated the role of 1,2-diacylglycerol, one of the products of receptor-linked phosphatidylinositol hydrolysis, in mediating the migratory response of leukocytes. In an under-agarose migration system, we found 1,2-dioctanoylglycerol to be a strong chemoattractant for human PMN, 6C3HED (a mouse thymic lymphoma), and Jurkat (a human T-cell leukemia). By using a modified Boyden chamber assay, the migratory response of PMN to 1,2-dioctanoylglycerol was determined to be primarily chemotactic. Analysis of structural analogs indicated that both the position and number of acyl chains are important in determining chemoattractant activity. These studies demonstrate that exogenous 1,2-diacylglycerol can stimulate the directed migration of leukocytes. They further suggest that the formation of 1,2-diacylglycerol following receptor-mediated stimulation may represent a common step in the migratory responses of myeloid and lymphoid cells. 相似文献
67.
68.
69.
Yang-Sheng Tzeng Eric Hoffman Janice Cook-Granroth Rie Maurer Niral Shah Joey Mansour Juerg Tschirren Mitchell Albert 《Magnetic resonance in medicine》2007,58(3):636-642
An anthropomorphic airway tree phantom was imaged with both hyperpolarized (HP) 3He MRI using a dynamic projection scan and computed tomography (CT). Airway diameter measurements from the HP 3He MR images obtained using a newly developed model-based algorithm were compared against their corresponding CT values quantified with a well-established method. Of the 45 airway segments that could be evaluated with CT, only 14 airway segments (31%) could be evaluated using HP 3He MRI. No airway segments smaller than approximately 4 mm in diameter and distal to the fourth generation were adequate for analysis in MRI. For the 14 airway segments measured, only two airway segments yielded a non-equivalent comparison between the two imaging modalities, while eight more had inconclusive comparison results, leaving only four airway segments (29%) that satisfied the designed equivalence criteria. Some of the potential problems in airway diameter quantification described in the formulation of the model-based algorithm were observed in this study. These results suggest that dynamic projection HP 3He MRI may have limited utility for measuring airway segment diameters, particularly those of the central airways. 相似文献
70.