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981.
The feasibility of using the murine monoclonal antibody, TP-1, for clinical immunoscintigraphy was examined in a pilot study involving 5 patients with bone sarcomas. 131I-labelled F(ab')2 antibody fragments were injected in doses of 0.8-1.0 mg (90-130 MBq), and the accumulation of radioactivity was examined by scintigraphy, and assessed by direct measurements on biopsied tumour and normal tissue. One osteosarcoma patient had a primary tumour in the femur, whereas the other 4 had single lung metastases detected by other diagnostic methods. Immunoscintigraphy of the femoral primary was optimally visualised after 22 h. In 2 patients, the method failed to detect lung metastasis, in 1 of the cases possibly related to less than optimal methodological conditions. In 2 other patients, increased accumulation of radioactivity indicated one and three lung tumours, in addition to the single metastasis observed by X-ray and CT scanning, tumours that were later confirmed and removed surgically. The concentration of radioactivity in tumour and normal tissues 44-72 h after antibody injection could be measured in 4 patients. The tumour to blood ratios were in the range of 1.2-4.2, compared to 0.1-0.8 for various normal tissues. The results indicate that immunoscintigraphy with TP-1 antibody fragments have a potential for early detection of lung metastases in patients with bone sarcoma.  相似文献   
982.
983.
The present study describes the development of an enzyme-linked immunosorbent assay capable of quantifying serum antibody of all four canine IgG subclasses. A panel of subclass-restricted and subclass-specific monoclonal antibodies was used to measure IgG subclasses in the serum of healthy dogs, as well as in dogs with a range of clinical diseases. The subclasses have been redefined as IgG1, IgG2, IgG3 and IgG4 based on a comparison with the relative concentration and electrophoretic mobilities of human IgG subclasses. In serum samples from healthy dogs, the concentration of IgG1 (mean, 8.17 +/- 0.95 mg ml-1) and IgG2 (mean, 8.15 +/- 3.16 mg ml-1) were very similar and considerably higher than the levels of IgG3 (mean, 0.36 +/- 0.43 mg ml-1) and IgG4 (mean, 0.95 +/- 0.45 mg ml-1). There was no apparent difference in the level of subclasses between the different breeds comprising this normal population. Sera from dogs with a range of immune-mediated or inflammatory diseases all had markedly elevated levels of IgG2 (more than 13 mg ml-1), but IgG1 decreased (less than 4 mg ml-1) to levels below the normal range.  相似文献   
984.
To study the time-course of infectious asthma, we retrospectively examined FEV1 from 5 days before to 10 days after the onset of illness in 31 asthmatic children (20 boys and 11 girls), aged 8 to 12 years. Infections were confirmed by a rise of at least fourfold in serum compliment fixation titers (respiratory syncytial virus, adenovirus, and Mycoplasma pneumoniae) and hemoagglutination inhibition titers (parainfluenza virus types 1, 2, and 3). All the patients had 20 percent or more fall in FEV1 from baseline value during acute phase, but were clinically tolerable and required minimum or no bronchodilators. Regardless of infectious agent, FEV1 began to fall on the first disease day or the previous day, and deteriorate for the first few days. Mean(SD) maximum fall in FEV1 ranged from 39(12) percent to 45(20) percent. Thereafter, FEV1 began to improve and returned to the preillness level by the seventh to tenth day. These results suggest that progressive bronchial obstruction may be inevitable during the acute stage of any infectious asthma.  相似文献   
985.
986.
Comments on K. S. Pope and V. A. Vetter's (see record 1992-25072-001) survey results on ethical dilemmas faced by members of psychology organizations. The author notes 2 specific concerns about psychology organizations accepting financial sponsorship from organizations that financially benefit from the sponsorship: the potential for a conflict of interest and the financial burden on the clients of psychology organizations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
987.
988.
The influences of the Samarra impoundment on the ecology of the downstream sector of the river Tigris are investigated. Zooplankton were collected monthly from July 1987 to July 1988. It was found that zooplankton were most abundant during high river discharges in March. During the month of low river discharge, September, the zooplankton population was greatly reduced immediately below the barrage and remained so to the last downstream station. Several factors seem to explain such differences. The high discharge from the impoundment was found to be the dominating factor and may flush the small backwaters in which zooplankton were abundant, thus increasing the population in the river. Zooplankton species vary in their ability to sustain populations in the river, variations which are due mainly to species-specific characteristics.  相似文献   
989.
BACKGROUND AND PURPOSE: Since functional transcranial Doppler ultrasonography (fTCD) allows convenient and fully automated quantification of language lateralization, it seems ideal for longitudinal studies of perfusion changes during deterioration as well as recovery of language functions. However, during serial examinations, the technical, stochastic, and physiological variabilities of cerebral blood flow velocities (CBFV) have to be considered. Therefore, before fTCD is accepted as a tool for evaluation of changes in lateralization in the diseased state, its reliability in healthy subjects needs to be determined. METHODS: We performed fTCD during a word generation task based on a previously validated technique with automated calculation of the averaged CBFV differences in the middle cerebral arteries providing an index of lateralization (LI). RESULTS: (1) The accuracy of the LI as assessed by the confidence interval was better than 1% of the mean hemispheric difference. (2) On repeated examination, LIs obtained from 10 subjects showed a high test-retest reproducibility (Pearson product moment correlation coefficient r = 0.95, P < 0.0001). (3) On 10 repeated assessments of LI in the same subject, no practice effects were detected. CONCLUSIONS: Functional TCD is a suitable and very robust tool for the longitudinal quantitative measurement of cerebral language lateralization.  相似文献   
990.
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