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991.
Binding kinetic studies with XV459, the active form of DMP754, demonstrated comparable binding kinetics (Kd and Koff) with platelets obtained from either human or baboons which were different from that with platelets obtained from dogs. Therefore, the present study was undertaken to evaluate the antiplatelet efficacy of DMP754 following oral administration in baboons. The dose levels evaluated were 0.1 and 1.0 mg/kg, IV and 0.1, 0.3, 1.0, and 3.0 mg/kg, oral of DMP754. Oral doses of DMP754 resulted in dose- and time-related inhibition of platelet aggregation along with a modest effect on bleeding time prolongation. DMP754 at similar oral doses had 24 hours of antiplatelet effects in baboon as compared to 8-12 hours duration of antiplatelet efficacy in dogs. At maximal antiplatelet doses DMP754 demonstrated no significant effects on platelet count, clinical chemistry or hemodynamic profiles in baboons. These data suggest that DMP754 is a potent orally active antiplatelet agent with extended duration after once a day oral administration in non-human primate. 相似文献
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994.
F Barchiesi RJ Hollis SA Messer G Scalise MG Rinaldi MA Pfaller 《Canadian Metallurgical Quarterly》1995,23(3):99-103
Electrophoretic karyotype (EK) was used to type 13 clinical isolates of Cryptococcus neoformans from eight AIDS patients. All of the isolates were also tested for their in vitro susceptibilities to fluconazole, itraconazole, D0870, flucytosine, and amphotericin B by a broth macrodilution technique performed according to the National Committee for Clinical Laboratory Standards recommendations. Although all strains were isolated from a limited geographic area, DNA typing showed a wide genetic variation in this group of patients, yielding seven different patterns. Two patients in whom C. neoformans was isolated in the same time period shared similar EK profiles, suggesting the possibility of cross-infection. In three patients, sequential isolates were evaluated: in two of them, EK analysis showed the persistence of the same genotype throughout the infection, whereas from the third, two isolates of C. neoformans with two different DNA profiles were obtained. Despite the small number of strains considered in this study, our susceptibility data indicate that C. neoformans isolates are very susceptible to the new triazoles. 相似文献
995.
To assess the role of altered alpha 2 beta 1 integrin expression in breast cancer, we expressed the alpha 2 beta 1 integrin de novo in a poorly differentiated mammary carcinoma that expressed no detectable alpha 2-integrin subunit. Expression of the alpha 2 beta 1 integrin resulted in a dramatic phenotypic alteration from a fibroblastoid, spindle-shaped, non-contact-inhibited, motile, and invasive cell to an epithelioid, polygonal-shaped, contact-inhibited, less motile, and less invasive cell. Although expression of the alpha 2 subunit did not alter adhesion to collagen, it profoundly altered cell spreading. Re-expression of the alpha 2 beta 1 integrin restored the ability to differentiate into gland-like structures in three-dimensional matrices and markedly reduced the in vivo tumorigenicity of the cells. These results indicate that the consequences of diminished alpha 2 beta 1-integrin expression in the development of breast cancer and, presumably, of other epithelial malignancies are increased tumorigenicity and loss of the differentiated epithelial phenotype. 相似文献
996.
Auditory brain-stem potential findings in 154 healthy infants and infants with different forms of middle-ear pathological conditions (306 ears) were indicative of the inflammatory process influence on the parameters of auditory reception in most cases. The changes in the waves' forms and intraoperative morphological findings in the middle ear were correlated. Objective audiometry allows definite determination of the middle ear trouble which is important in diagnosis of latent otitis in infants who are especially prone to this disease. 相似文献
997.
LL Klein L Li CJ Maring CM Yeung SA Thomas DJ Grampovnik JJ Plattner 《Canadian Metallurgical Quarterly》1995,38(9):1482-1492
A novel reduced taxane, 13-acetyl-9(R)-dihydrobaccatin III (1) has been isolated from Taxus canadensis. The selective C-13 deacetylation of this isolate has allowed for the preparation of a wide variety of 9(R)-dihydrotaxane analogs. In general, this series has shown greater stability and water solubility than the 9-carbonyl series while retaining antimicrotubule and tumor cell cytotoxicity activities relative to taxol. Placement of polar functionalities at the C-7 position results in loss of activity whereas alkylation or acylation of either C-7 or C-9 hydroxyl groups ameliorate the activity. 相似文献
998.
A comparison of deaf and hearing subjects in visual nonverbal sensitivity and information processing
Cardiotocography still is the main method to monitor the unborn child during birth. Today, problems occurring during CTG-surveillance are not so much due to the method, but a consequence of insufficient management. Fetal monitoring by combined CTG and FBA brings advantages for mother and child. The use of FBA in cases with pathological fetal heart patterns leads to a significant reduction in cesarean section rate, neonatal morbidity and perinatal mortality. 相似文献
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1000.
BACKGROUND: In the adult male rat prostate, castration induces apoptosis of epithelial cells concomitant with the increase in transforming growth factor-beta 1 (TGF-beta 1). In the present study, we investigated the effects of castration on apoptosis and TGF-beta 1 mRNA in neonatal mouse seminal vesicles. METHODS: 5-day-old BALB/c mice were castrated by Pfeifer's method. We estimated the weight, 3H-thymidine uptake by whole seminal vesicles, the amount of TGF-beta 1 mRNA by RT-PCR method, and the apoptotic index of both epithelium and mesenchyme. RESULTS: The castration of 5-day-old neonatal mice resulted in much less weight of seminal vesicles and DNA synthesis estimated by 3H-thymidine uptake by whole seminal vesicles compared to intact neonatal mice, indicating that the growth of neonatal mouse seminal vesicles depends on androgens secreted by the testis. The amount of TGF-beta 1 mRNA estimated by RT-PCR method increased 4 days after castration at 5 days of age. However, the castration did not induce apoptosis in the seminal vesicles. CONCLUSION: The present study indicates that castration of neonatal mice does not induce apoptosis in the seminal vesicles, although it does a transient increase in TGF-beta 1 mRNA in the seminal vesicles. 相似文献