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991.
Fourty-four primary brain tumors were studied by immunohistochemistry. 29 (67.2%) expressed HLA-Dr. The incidence and number of tumor cells positive for HLA-Dr correlated with the histological type of brain tumor and increased with the degree of malignancy. The mononuclear cells infiltrating in these tumors were mostly CD45ROT cells and macrophages. The former consisted mainly of CD4 and CD8 subsets. The numbers of CD45RO+ and CD8+ T cells in HLA-Dr-group were more than any of the HLA-Dr+, +2, +3 groups. The numbers of CD4 subset and macrophages were not affected by the level of HLA-Dr expression. These results suggest that the HLA-Dr expressed by brain tumor cells selectively inhibit CD8 subset which participates in immunoreaction against brain tumors in situ. 相似文献
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Notechis scutatus scutatus venom contains several toxic acidic proteins called HTa-i which promote hypotension and hemorrhage in mice. They have apparent mol. wts in the 18,000-21,000 range, i.v. LD50 values between 0.5 and 1.5 micrograms/g, and no detectable phospholipase, arginine esterase, proteolytic or hemolytic activities. A polyclonal antibody raised against HTg binds to other purified proteins, suggesting that they are isoforms of the same protein. Many other elapid crude venoms contain proteins which recognize the polyclonal antibody raised against HTg. Crotalid and viperid crude venoms do not recognize this antibody, although some of their component proteins are known to exhibit hypotensive and hemorrhagic activities. A combination of gel-filtration on Sephacryl S-200, cation-exchange and anion-exchange chromatography allows isolation of the N. s. scutatus proteins in high purity. They are the first hypotension-inducing proteins to be purified from an Australian elapid. 相似文献
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ES Erffmeyer 《Canadian Metallurgical Quarterly》1982,38(3-4):240-249
The behavior of rhesus monkeys (Macaca mulatta) was observed via videotape recording during the 12 hour period from 6.00 p.m. to 6.00 a.m. Adult animals were housed in male/female pairs under one of three cage conditions: individual cage, mating cage and a larger 'group' cage. 20 categories of behavior were assessed and the resultant behavior was described and quantitatively compared across cage conditions. The animals spent almost the entire night in a sitting position, either alone or while huddling with another animal. Sitting and huddling behavior are near-perfect complements to each other in terms of the frequency of occurrence; taken together they account for almost the entire nocturnal behavior. Other activity rarely displaces these behaviors. The animals tended to be relatively active in the early evening. As night fell, they settled down to relative inactivity, which they maintained until the morning. The activity level gradually increased as dawn approached. 相似文献
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RM Conry MB Khazaeli MN Saleh V Ghetie ES Vitetta T Liu AF LoBuglio 《Canadian Metallurgical Quarterly》1995,18(4):231-241
In a phase I trial, eight patients with non-Hodgkin's B-cell lymphoma received mouse IgG1k monoclonal antibody HD37 specific for CD19 conjugated to deglycosylated ricin A chain (dgA) administered in four doses at 4-h intervals with total doses ranging from 4-12 mg/m2. This schedule generated serum levels of immunotoxin which were sustained over 36 h. The plasma half-life of HD37-dgA was 17 +/- 4 (SD) h. The HD37-dgA conjugate was stable in vivo as demonstrated by serum levels of HD37-dgA conjugate comparable to those of total HD37 antibody. Peak serum levels attained after the fourth dose ranged from 0.36 to 5.63 micrograms/ml. Two of seven evaluable patients developed modest human anti-immunotoxin antibody responses. Toxicity in patients 1-7 consisted of dose-dependent capillary leak syndrome with hypoalbuminemia, orthostatic hypotension, and weight gain. Patient 8 died on day 8 with severe capillary leak, bronchopneumonia, and rhabdomyolysis. All patients had progressive disease at 4 weeks except patient 8, who exhibited a near-complete remission before his death. This intensive schedule appears to produce inordinate toxicity with a maximal tolerated total dose of 8 mg/m2. 相似文献