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21.
CI-921, an anilinoacridine compound active against leukemicand solid tumors, was evaluated for potential developmentaltoxicity. Intravenous injections of CI-921 in dextrose weregiven to female Sprague-Dawley rats (0.1, 0.5, and 1.0 mg/kg)on Gestation Days (GD) 615 and to female New ZealandWhite rabbits (0.1, 1.0 and 2.0 mg/kg) on GD 618. Appropriatevehicle and untreated controls were included. Maternal and fetalparameters, including external, visceral, and skeletal malformationsand variations, were assessed. Treatment of rats with 1.0 mg/kgresulted in maternal toxicity, manifested as reduced body weightgain and food consumption during and after treatment. Reducedfetal body weight, an increased incidence of stunted fetuses,malformations of the axial and appendicular skeleton, microphthalmia,and an increased number of anatomical variations (includinganomalies of the axial skeleton and apparent hydronephrosis)also occurred in rats at 1.0 mg/kg. Treatment of rabbits resultedin no apparent maternal toxicity. However, reduced fetal bodyweight, agenesis of the azygous lobe of the lung, and an increasedincidence of variations of the axial skeleton occurred at 2.0mg/kg in rabbits. These results indicate that CI-921, at thehighest dose tested in each species, produced developmentaltoxicity in the presence of maternal toxicity in rats, but inthe absence of maternal toxicity in rabbits. 相似文献
22.
BROWN JM 《Rocky Mountain medical journal》1949,46(12):1020-1023
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Discrepancies Between Perceived Dietary Changes and 4-Day Food Records in Older Adults with Diabetes
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NESBITT D. BROWN DENNIS L. BUTLER PETER K. CHIANG 《The Journal of pharmacy and pharmacology》1993,45(7):666-667
Abstract— Thymopentin prepared in 5, 15, and 20% 2-hydroxypropyl-β-cyclodextrin (HPCD) was able to inhibit guinea-pig ileum contraction stimulated by anatoxin-a (3 × 10?6 m ) after fourteen months of storage at room temperature. Thus, in contrast to the instability of thymopentin prepared without HPCD, the pharmacological activity was retained and could be stored in a ready-to-use solution for extended periods without refrigeration. 相似文献
29.
A monthly child psychiatric clinic was established in a primary health care centre in order to offer a more accessible service to patients, and to improve liaison with primary health care professionals. Compared with the base child guidance unit, at the health centre there was a better first attendance rate, a much higher proportion of referrals from health professionals especially general practitioners, and an increased proportion of younger children referred. If further follow-up was necessary at the child guidance unit the attendance rate was very good. The service provided, although not reducing the need for a main multidisciplinary base, offered an acceptable and accessible opportunity for children with psychological problems to be assessed and treated, and for the referring professionals to have easy communication with the child psychiatrist. 相似文献
30.
A single gene copy merozoite surface antigen and immune evasion? 总被引:1,自引:0,他引:1
During the course of chronic malaria infection antigenic variants of a parasite antigen are expressed and exposed on the surface of infected erythrocyte membranes. There also exists a number of apparently invariant single gene copy blood-stage antigens, exposed or non-exposed, which have been shown to afford immunity under experimental conditions. To determine why the host, presented with invariant 'protective' antigens, is unable to control infections effectively, immunity to a representative single gene copy antigen, the merozoite surface protein 1 (MSP1) was investigated in Plasmodium chabaudi chabaudi AS, a murine model of chronic malaria. Immunization with monoclonal antibody affinity purified native MSP1 resulted in enhanced control of parasitaemia on challenge, irrespective of the parasite inoculum size; challenge with a single parasite, however, suggested that expansion of resistant parasite subpopulations was not occurring. Challenge of mice immunized with recombinant fusion proteins encoding N- or C-terminal regions of the P.c. chabaudi AS MSP1 produced inconsistent effects, often parasitaemias were indistingishable from controls despite significant anti-MSP1 antibody responses. The not unlikely contamination of MSP1 native preparations with erythrocyte (E) components was considered. Immunization with a mixture of the MSP1 C-terminus recombinant polypeptide and a Triton X-100 solubilized lysate of normal E resulted in enhanced control of parasitaemia, however, no effect was seen after administration of either component on its own. Co-immunization of E with the N-terminus polypeptide reversed the inhibition seen, on this occasion with this construct alone. 相似文献