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141.
Effect of isoelectric point on biodistribution and inflammation imaging with indium-111-labelled IgG
Caroline I. ten Kate Alan J. Fischman Robert H. Rubin A. J. Fucello D. Riexinger Robert A. Wilkinson Lina Du Ban An Khaw H. William Strauss 《European journal of nuclear medicine and molecular imaging》1990,17(6-8):305-309
Electrostatic effects play an important role in protein interactions and may alter the biodistribution of antibodies. To study the effect of molecular charge on the biodistribution and infection imaging properties of human polyclonal immunoglobulin G (IgG), its iso electric point was varied by changing the level of diethylene triamine penta-acetic acid (DTPA) substitution: 0.8, 0.9, 3.7, 5.1 and 5.9 DTPA/IgG. Biodistributions of the different IgG preparations were determined at 10 min, 1, 6, 24, and 48 h post injection in normal rats, and infection imaging properties were determined in rats withEscherichia coli thigh infections. The biodistribution was significantly affected by pl. The immunoglobulin preparations with 0.9 and 3.7 DTPA/IgG showed faster clearance from the circulation and generally lower accumulation in most organs. The images had a target-to-background ratio of approximately 1.3–2.3:1. These results suggest that even though targeting is not affected by the level of DTPA substitutions, preparations with 0.9 and 3.7 DTPA/IgG may be superior imaging agents because of reduced accumulation by background organs. 相似文献
142.
William Muraskin 《Social science & medicine (1982)》1996,42(12):1703-1719
The Children's Vaccine Initiative (CVI) was created as an attempt to revolutionize the way vaccines are developed for the developing world. It was formed, in part, out of optimism that the scientific advances of the biotechnology revolution could be harnessed to create new and improved vaccines, and in part out of fear that the health needs of the developing world would be ignored by the increasingly profit-oriented vaccine industry that gave low priority to countries lacking a hard currency market. The CVI was founded in 1990/1991 but its intellectual roots came out of ten years of discussion and agitation about the opportunities and dangers that faced the international health community. The article looks at the indispensable role played by pivotal individuals (William Foege of the Task Force for Child Survival, Kenneth Warren and Scott Halstead of the Rockefeller Foundation, James Grant and James Sherry of UNICEF and D. A. Henderson of Johns Hopkins University) without whom the CVI would not have come into existence. While these individuals worked within the confines created by the large social/economic/political changes that shaped the 1980s, their personal goals, often targeted at fairly limited objectives, were crucial in determining the final, rather unlikely, outcome. The role of both individual choice and serendipity in determining major policy decisions are often under-estimated in the social science literature. 相似文献
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Jin S. Lee Herman I. Libshitz William K. Murphy Diane Jeffries Waun K. Hong 《Investigational new drugs》1990,8(3):299-304
Summary Thirty-one patients with stage IIIB or IV non-small cell lung cancer (NSCLC) were treated with intravenous 10-EdAM on a weekly basis. The starting dose was 80 mg/m2, with subsequent doses adjusted depending on evidence of toxicity. There were 20 men and 11 women with a median age of 58 years (range, 33–75). Response was evaluated in 30 patients, 5 with evaluable but not measurable tumors and 25 with measurable indicator lesions. There were no complete remissions; 3 patients achieved partial remission. Nine patients had a minor response, 6 showed no change, and 12 had progressive disease. Median survival for all 31 patients was 43 weeks (range, 12–65+). During the first 3-week period, the 10-EdAM dose was reduced or withheld in 19 patients (because of stomatitis in 12, SGPT elevation in 3, skin rash in 2, and granulocytopenia in 2), escalated in 11 patients, and unchanged in 1 patient. A mean of 34–88 mg/m2of 10-EdAM (median, 50) was given per week during the first 5-week period. Myelotoxicity was infrequent and there was no significant nephrotoxicity. Considering the modest side effects of this treatment and the conservative dose-modification schedule which mandated substantial dose reductions, we conclude that 10-EdAM is a promising antitumor agent for NSCLC. 相似文献
146.
Dr. Yoshihiko Hayakawa Ph.D. Allan G. Farman B.D.S Ph.D. D.Sc. William C. Scarfe B.D.S M.S. Kinya Kuroyanagi D.D.S Ph.D. 《Oral Radiology》1996,12(1):11-18
The RVG-4 permits automatic exposure compensation (AEC). The purpose of this investigation was to determine the effects of
AEC on image contrast. Images were made either with or without a dental QA jaw phantom using a fixed image projection geometry.
Exposures were 6.3 through 27.3 μC/kg using an X-ray generator operated at 70 kVp. Region of interest pixel value distributions
were measured at tissue thicknesses in this phantom, and the average pixel values and signal-to-noise ratios (SNR) were calculated.
The use of AEC without an object in place resulted in a disproportionate relationship between pixel value and exposure with
a marked reduction in SNR. The use of AEC on under- and over-exposed images of the phantom simultaneously enhanced image contrast
and reduced SNR. Thus, AEC provides a convenient and quick method for achieving high-contrast images with sub-optimal exposures,
however, this could lead to inappropriate patient dosages if the function is used for over-exposed images. AEC reduces the
SNR and produces disproportionate pixel values relative to exposure. 相似文献
147.
William C. Wasmund 《Child & youth care forum》1988,17(3):146-155
Some presumed strengths and weaknesses of peer group approaches are discussed as the basis for this study, in which students' and staff members' perceptions of social climates in two peer-group and two non-peer-group residential treatment agencies were compared. Students from the peer group agencies sampled reported significantly greater satisfaction with their social climates than their non-peer-group contemporaries, and staff/student perceptions were more congruent in the peer group agencies than in the non-peer-group agencies. The results suggested that peer group programs can provide healthy, responsible therapeutic communities, and other implications are discussed as well. 相似文献
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A 73-year-old woman presenting with persistent swelling of the right knee 30 months after total joint arthroplasty was found to have a Candida parapsilosis infection. Treatment with fluconazole resulted in full recovery. 相似文献