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991.
P Carde C Chastang E Goncalves N Mathieu-Tubiana E Vuillemin V Delwail O Corbion A Vekhoff F Isnard J M Ferrero 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1992,315(13):545-550
Seraspenide, a synthetic tetrapeptide, inhibits cell cycle entry of normal hematopoietic stem cells. In mice it protects hemopoiesis against the damage caused by cytarabine, cyclophosphamide and carboplatin. Seraspenide has been given to 53 cancer patients undergoing monochemotherapy with cytarabine and ifosfamide in a double-blind cross-over randomized study. A significant protection of peripheral blood cells has been observed. Seraspenide has been devoided of toxicity. 相似文献
992.
24 patients with non-Hodgkin's lymphomas of low-grade malignancy (stage III and IV) were treated either with a single drug (prednimustine) or with combination chemotherapy (cyclophosphamide, vincristine and prednisone). Response to therapy was similar in both groups. Prednimustine induced complete remission in 6 from 13 patients, while in that group treated with combination chemotherapy a complete remission was recorded in 4 from 11 patients. Both regimens were well tolerated. Therapy with prednimustin has an advantage in oral administration enabling it to be used in out-patient practice. 相似文献
993.
In the mesenterium of rats it was found that an overacidity of the blood flowing in the area of microcirculation and caused by irrigation with acid media may be objectively represented in the clearing of venols measurable by means of video technique. The cause of this clearing process is the swelling of erythrocytes setting in at lower pH-values. According to in-vitro findings this swelling of erythrocytes will lead to an increase of the apparent viscosity of the blood fluid or blood cell suspension respectively in conformity with the increase of hematocrit connected with it. 相似文献
994.
995.
996.
E D Bershadskaia N G Fish P P Shev'ev M A Osipov V I Ogarkov 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1986,(9):32-35
Anabol and blastolysin preparations obtained from L. bulgaricus may contain surface structural components of the initial strain with adhesion activity; of these, one is similar in specificity to L. casei adhesin and the other, to L. plantarum adhesin. The antigenic activity of anabol and blastolysin, evaluated in the immunodiffusion test, does not correlate with their capacity for binding the receptors of susceptible bacterial cells, determined in the Lactobacillus-induced hemagglutination inhibition test. 相似文献
997.
Overproduction from a cellulase gene with a high guanosine-plus-cytosine content in Escherichia coli 总被引:1,自引:0,他引:1
G P O'Neill D G Kilburn R A Warren R C Miller 《Applied and environmental microbiology》1986,52(4):737-743
A recombinant exoglucanase was expressed in Escherichia coli to a level that exceeded 20% of total cellular protein. To obtain this level of overproduction, the exoglucanase gene coding sequence was fused to a synthetic ribosome-binding site, an initiating ATG, and placed under the control of the leftward promoter of bacteriophage lambda contained on the runaway replication plasmid vector pCP3 (E. Remaut, H. Tsao, and W. Fiers, Gene 22:103-113, 1983). With the exception of an inserted asparagine adjacent to the initiating ATG, the highly expressed exoglucanase is identical to the native exoglucanase. The overproduced exoglucanase can be isolated easily in an enriched form as insoluble aggregates, and exoglucanase activity can be recovered by solubilization of the aggregates in 6 M urea or 5 M guanidine hydrochloride. Since the codon usage of the exoglucanase gene is so markedly different from that of E. coli genes, the overproduction of the exoglucanase in E. coli indicates that codon usage may not be a major barrier to heterospecific gene expression in this organism. 相似文献
998.
999.
Summary The rate of flow and nitrate and phosphorus content of the water from four drained sandy and clayey plots of size 12×60 m
cropped to continuous corn were determined following two annual applications of different rates (0, 260, 390 and 520 kg N/ha)
of cow manure slurry. The drain flow was directly related to the rainfall and was greatly influenced by soil texture. The
N losses were greater in 1972 (7.8 to 19.1 kg N/ha) than in 1971 (0.4 to 7.8 kg N/ha) because of more summer rainfall. Nitrogen
and phosphorus losses were larger from the sandy plots than from the clayey plots. The manure application rates had no apparent
effect on nitrogen losses in the drain water. 相似文献
1000.
Dehalogenation of 4-chlorobenzoate by 4-chlorobenzoate dehalogenase from pseudomonas sp. CBS3: an ATP/coenzyme A dependent reaction 总被引:7,自引:0,他引:7
F L?ffler R Müller F Lingens 《Biochemical and biophysical research communications》1991,176(3):1106-1111
Pseudomonas sp. CBS3 was grown with 4-chlorobenzoate as sole source of carbon and energy. Freshly prepared cell-free extracts converted 4-chlorobenzoate to 4-hydroxybenzoate. After storage for 16 hours at 25 degrees C only about 50% of the initial activity was left. Treatment at 55 degrees C for 10 minutes, dialysis or desalting of the extracts by gel filtration caused a total loss of the activity of the 4-chlorobenzoate dehalogenase. The activity could be restored by the addition of ATP, coenzyme A and Mg2+. If one of these cofactors was missing, no dehalogenating activity was detectable. The amount of 4-hydroxybenzoate formed was proportional to the amount of ATP available in the test system whereas CoA served as a real coenzyme. A novel ATP/coenzyme A dependent reaction mechanism for the dehalogenation of 4-chlorobenzoate by 4-chlorobenzoate dehalogenase from Pseudomonas sp. CBS3 is proposed. 相似文献