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191.
192.
193.
Eric Delson 《Journal of Mammalian Evolution》2007,14(3):198-199
194.
The influence of moulded hay (Alternaria alternata, Epicoccum nigrum, Mucor racemosus, Ulocladium chartarum) and the efficiency of Vitamin B1 substitution to cope these effects on rumen protozoa was investigated using the longterm rumen simulation technique (RUSITEC) for about 25 days. Moulded hay affected medium-sized protozoa to a different extent (Alternaria alternata: ?16 %, Epicoccum nigrum: ?27 %, Mucor racemosus: ?9 %, Ulocladium chartarum: +2 %). The vitamin B1 substitution had positive effects during the feeding of Mucor racemosus and Ulocladium chartarum. 相似文献
195.
Jerzy Chelkowski Piotr Zajkowski Marcin Zawadzki Juliusz Perkowski 《Mycotoxin Research》1987,3(1):25-32
An isolated rat liver was perfused with deoxynivalenol (DON) at a dose of 3 mg in a recirculating perfusion system. To identify glucuronide conjugates equal amounts of bile samples, perfusate and liver homogenates were incubated with and without (control) a β-glucuronidase preparation and analyzed by thin layer chromatography and capillary gas liquid chromatography — chemical ionization mass spectrometry. A total of 40.4% of the administered dose of DON was found to be conjugated with glucuronic acid (perfusate 20.4%, bile 19.2%, liver 0.8%), while only 1.3% of the parent DON (perfusate 1.1%, bile 0.2%) was detected. The cleavage of DON-glucuronide was demonstrated by incubating DON-glucuronide containing bile samples with intestine contents under anaerobic conditions. 相似文献
196.
3H-azidopine photoaffinity labeling of high molecular weight proteins in chloroquine resistant falciparum malaria 总被引:1,自引:0,他引:1
Z G Ye K Van Dyke T Spearman A R Safa 《Biochemical and biophysical research communications》1989,162(2):809-813
Using 3H-azidopine, we have succeeded in labeling proteins from chloroquine resistant (CR) human falciparum malaria parasites in the molecular weight range of 155-170 kd. Vinblastine does not compete, but azidopine blocks the labeling using 3H-azidopine. Relatively little or no labeling of the 155-170 kd protein is seen in the chloroquine sensitive strain using 3H-azidopine. Further competition can be seen with nicardipine and reserpine (71%) respectively and verapamil (61%), chloroquine (48%), quinacrine (56%), trifluoperazine (32%) and chlorpromazine (33%). We speculate that this may be the glycoprotein responsible for the resistance to chloroquine in falciparum malaria. 相似文献
197.
Photoaffinity labeling of P-glycoprotein in multidrug resistant cells with photoactive analogs of colchicine 总被引:3,自引:0,他引:3
A R Safa N D Mehta M Agresti 《Biochemical and biophysical research communications》1989,162(3):1402-1408
Two photoactive radiolabeled analogs of colchicine, N-(p-azido[3,5-[3H]benzoyl)aminohexanoyldeacetylcolchicine ([3H]NABC]) and N-(p-azido-[3-125I]salicyl)aminohexanoyldeacetylcolchicine ([125I]NASC) were synthesized and used to identify colchicine-specific acceptor(s) in membrane vesicles from multidrug resistant (MDR) variant DC-3F/VCRd-5L Chinese hamster lung cells. Both [3H]NABC and [125I]NASC specifically photolabeled a prominent 150-180 kDa polypeptide in membrane vesicles from DC-3F/VCRd-5L cells. The photolabeled polypeptide was immunoprecipitated by monoclonal antibody C219 specific for the MDR-related P-glycoprotein (P-gp) indicating the identity of this protein with P-gp. Colchicine at 1000 microM reduced [3H]NABC photolabeling of P-gp by 72%. Furthermore, 100 microM of colchicine, vincristine, vinblastine, doxorubicin and actinomycin D inhibited [125I]NASC photolabeling by 45, 88.8, 91.1, 61.5, and 51% respectively. However, methotrexate did not affect the [125I]NASC photolabeling of P-gp, indicating the multidrug specificity of the P-gp colchicine acceptor for drugs to which these cells are resistant. 相似文献
198.
199.
Kazuhiro Nakaya 《Ichthyological Research》1988,34(4):431-442
Data on the individual variation and changes with growth in proportions and morphology are presented for the poorly known Apristurus longicephalus, and compared with those of other species. A. longicephalus is concluded to be a distinct species without synonyms, characterized by its long snout, widely separate nostrils, long caudal fin, short abdomen, very sparse teeth, and low number of monospondylous vertebrae. It is a species of small size, maturing at about 42 cm in total length. 相似文献
200.
Scale morphology, growth and the squarnation chronology are described for the hermaphroditic fish Rivulus marmoratus reared in the laboratory. The scales are round or oval shaped cycloid type, and their sizes are about 0.3–1.0 mm in diameter. The number of ridges increases more rapidly relative to the body growth of the fish in early stages, but this increase is proportionate to growth subsequently. Three loci of scale development have been identified. The scales first appeared on the center of the parietal region at 8 days after hatching. The second locus of scale formation was on the lateral line of the posterior end of the caudal peduncle. A third locus was later observed on the lower right corner of the operculum: The final squamation was completed at 6 weeks after hatching. 相似文献