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11.
The clinical efficacy of aclarubicin, an anthracycline antibiotic, was studied in 48 patients with leukemia. The antibiotic was used in the following combinations with cytarabine: "7 + 7", "5 + 5" and "7 & 3". A complete remission was stated in 14 (42.4 per cent) out of 33 patients with acute nonlymphoid leukemia, 6 (43 per cent) out of the 14 patients having relapses. The combined therapy was effective in 4 out of 5 pre-resistant patients. The "7 + 3" scheme was the most beneficial. The most common adverse reactions were nausea and vomiting.  相似文献   
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New site-specific endonucleases LplI and AagI have been isolated from the Lactobacillus plantarum and Achromobacter agile cells, respectively. The enzymes' purification stages included treatment of cell-free extracts with polyethylenimine, fractionation in two-phase system by Albertsson's method, chromatography on blue Sepharose and DEAE-cellulose. The results of cleavage of a 5'-32P-labelled oligodeoxynucleotide duplex by restriction endonucleases LplI and AagI indicate that these enzymes recognize and cut the sequence AT decreases CGAT, being therefore true isoschizomers of the ClaI restriction endonuclease from Caryophanon latum. The L. plantarum strain has 400 fold endonuclease productivity as compared with the ClaI producent and is perspective for preparative isolation of LplI.  相似文献   
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The expression of gene(s) governing apomictic reproduction inTripsacum provides the best foundation for comparing the effectiveness of apomictic reproduction in a series of maize-Tripsacum hybrids. Several 38-chromosome, apomictic maize-Tripsacum hybrids are available which possess the gene(s) conferring apomictic reproduction fromTripsacum. Without a base line for comparison, studies directed towards discerning the successful transfer or effectiveness of gene expression in a maize background are hampered. The objectives of this study are to compare the reproductive features found in apomicticTripsacum with those in apomictic maize-Tripsacum hybrids. In addition, this study determined the feasibility of utilizing these maize-Tripsacum hybrid materials to continue an attempt to transfer the genes into a pure maize background. The frequency and occurrence of five unique reproductive features found in apomictic accessions ofTripsacum dactyloides were compared to the reproductive behaviours exhibited in the maize-Tripsacum hybrids. Results indicate the genes controlling apomixis in tetraploidTripsacum are fully functional in maize-Tripsacum hybrids with diploid and triploid maize constitutions. The ability of theTripsacum apomictic genes to retain full expression provides evidence to continue their transfer to a diploid or tetraploid maize background.The use of company names in this publication does not imply endorsement by the USDA-ARS, or the product names or criticism of similar ones not mentioned. All programs and services of the U.S. Department of Agriculture are offered on a nondiscriminatory basis without regard to race, color, national origin, religion, sex, age, marital status, or handicap.  相似文献   
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Minimal photosynthetic catalytic F1() core complexes, containing equimolar ratios of the and subunits, were isolated from membrane-bound spinach chloroplast CF1 and Rhodospirillum rubrum chromatophore RrF1. A CF1-33 hexamer and RrF1-11 dimer, which were purified from the respective F1() complexes, exhibit lower rates and different properties from their parent F1-ATPases. Most interesting is their complete resistance to inhibition by the general F1 inhibitor azide and the specific CF1 inhibitor tentoxin. These inhibitors were earlier reported to inhibit multisite, but not unisite, catalysis in all sensitive F1-ATPases and were therefore suggested to block catalytic site cooperativity. The absence of this typical property of all F1-ATPases in the 11 dimer is consistant with the view that the dimer contains only a single catalytic site. The 33 hexamer contains however all F1 catalytic sites. Therefore the observation that CF1-33 can bind tentoxin and is stimulated by it suggests that the F1 subunit, which is required for obtaining inhibition by tentoxin as well as azide, plays an important role in the cooperative interactions between the F1-catalytic sites.Abbreviations CF0F1 chloroplast F0F1 - CF1 chloroplast F1 - CF1 chloroplast F1 subunit - CF1 chloroplast F1 subunit - CF1() a complex containing equal amounts of the CF1 and subunits - MF1 mitochondrial F1 - RrF0F1 Rhodospirillum rubrum F0F1 - RrF1 R. rubrum F1 - RrF1 R. rubrum F1 subunit - RrF1 R. rubrum F1 subunit - RrF1() a complex containing equal amounts of the RrF1 and subunits - Rubisco Ribulose-1,5-bisphosphate carboxylase - TF1 thermophilic bacterium PS3 F1  相似文献   
17.
The restriction fragment length polymorphisms (RFLPs) of 3 collagen genes have been studied in two USSR populations. Four high-frequency alleles, also reported in other populations, were observed. The frequencies of alleles for the polymorphic sites MspI and EcoRI of the COL1A2 gene, HindIII of the COL2A1 gene and EcoRI of the COL3A1 gene were found to be 0.836, 0.398, 0.447 and 0.786, respectively, in Russians from Moscow (Caucasians), and 0.883, 0.519, 0.648 and 0.809, respectively, in Buryats from the Baikal region (Mongoloids). The RFLPs showed a fair agreement with the Hardy-Weinberg equilibrium. The frequencies were compared with those of other populations.  相似文献   
18.
Seventy heart preparations of persons belonging to different sex and age have been investigated, using a complex of anatomical and histological techniques. The dimensions of the sinoatrial node (SAN) vary with age and depend on various size and form of the heart. The large atrial branch of the right and left coronary arteries supplies mainly the SAN with blood. More seldom the atrial branches of both cardiac arteries, having anastomoses, realize the SAN blood supply. The character of the SAN vascularization depends on branching variations of the atrial vessels. At the right coronary variant the sources of the SAN blood supply are the SAN branch, the right intermediate or right posterior atrial branches, and at the left coronary variant--the anterior left, the posterior left and the intermediate left atrial branches. At the even variant the SAN blood supply sources are the right intermediate and the anterior left atrial or the right posterior and the left posterior atrial branches. The data obtained can be used for comparison with the results of coronography to make a skilled analysis of clinical-roentgenological observations.  相似文献   
19.
Possible extracorporeal removal of a novel water soluble derivative of amphotericin B (NWSDA) from the host was studied. The bench tests demonstrated that actilen, a fibrous carbon adsorbent, was the optimal carbon sorbent for sorption of NWSDA. It was shown in the acute experiments on animals that during the hemosorption the antibiotic blood concentration on the outlet of the column was significantly lower than that on the inlet. Still, the NWSDA concentration in the blood lowered slowly which was likely due to the return of the antibiotic to the blood from the tissues.  相似文献   
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