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41.
Summary In a cooperative randomized control study of immunotherapy with bestatin in combination with chemotherapy in adults with acute nonlymphocytic leukemia (ANLL), 101 patients (48 in the bestatin group and 53 in the control group) out of 115 patients registered were evaluated as eligible. The bestatin group achieved a statistically significant prolongation of survival compared with the control group in overall ANLL and acute myelogenous leukemia. In the analysis of patient age, the bestatin group achieved a statistically significant prolongation of both the remission duration and survival in patients aged 50 to 65 years, while the differences were not significant in the 15 to 49 age group. The bestatin group tended to achieve a higher rate of reinduction of remission in patients who had recurrence of leukemia. Side effects developed in only 5 (9.6%) of 52 patients treated with bestatin. None of these side effects were particularly serious in nature. It is concluded that bestatin is useful for prolongation of survival of adult patients with ANLL, making for a longer remission duration especially in elderly patients and with few side effects.  相似文献   
42.
Abstract The complete nucleotide sequence of pNS1 (3879 bp), a tetracycline-resistance (TcR) plasmid drived from staphylococcal plasmid pTP5, has been determined and compared with that of the staphylococcal TcR plasmid pT181 [6]. The nucleotide sequences of the 2 plasmids are in agreement, except for 18 nucleotides, but these differences are significant in that they give rise to new open reading frames (ORFs). A short ORF-D is found in the copy control region, and the TcR region contains a single large ORF-A, that encodes the Tet protein (50 kDa). The upstream region of ORF-A contains 3 inverted repeat sequences, which can generate structures very similar in conformation of the structure of the control region of the inducible erythromycin-resistance gene of pE194.  相似文献   
43.
The sex-specific glycoprotein agglutination substance, responsiblefor sexual agglutination, solubilized from the surface of haploidcells of a or a mating type by the autoclave method had thefollowing effects on mating reaction in Saccharomyces cerevisiae.Sexual agglutination was inhibited by the agglutination substanceof the opposite mating type in living cells as well as in heat-killedcells. Formation of zygotes was completely inhibited, when botha and a cells were treated with the agglutination substanceof the opposite mating type. The a and a agglutination substanceswere inactivated by cells of the opposite mating type, withthe degree of inactivation being greater for the former. Theenzyme responsible for the inactivation of a agglutination substanceseems to be carboxypeptidase Y. 1 This paper is dedicated to the late Professor J. Ashida, KyotoUniversity. 2 Present address: Department of Plant Pathology, Universityof California, Davis, CA. 95616, U.S.A. (Received November 1, 1982; Accepted January 19, 1983)  相似文献   
44.
Chromosomes and sex determination of 9 species of Haemaphysalis assigned to 4 subgenera are described. H. (tAlloceraea) kitaokai possesses an XX∶XO sex chromosome system with 18 autosomes plus XX in females; 18 plus X in males. H. (Kaiseriana) hystricis has 18 +XX and 18 + XY in females and males, respectively, in most specimens, but a supernumerary chromosome is present in some individuals. A supernumerary chromosome was also observed in 1 male H. (Aborphysalis) formosensis. These two species are the second and third species of ticks reported to have supernumerary chromosomes. H. formosensis, H. (Kaiseriana) bispinosa, H. (Haemaphysalis) campanulata, H. (H.) flava, H. (H.) megaspinosa, H. (H.) japonica, and H. (H.) pentalagi possess 20 autosomes plus 2 sex chromosomes in females and 20+1 sex chromosomes in males. Phylogenetic relationships within the genus Haemaphysalis are briefly discussed.  相似文献   
45.
Simple approximate expressions have been derived from the theory of Zimm and Bragg for use in the analysis of experimental data on the helix-coil transition in polypeptide. On the basis of the resulting expressions practical procedures are proposed to determine two basic parameters characterizing a thermally induced transition, i.e., helix initiation parameter σ and enthalpy change for helix formation, ΔH. They have been applied to the data for poly(β-benzyl L -aspartate) (PBLA) with the result: σ = 1.6 × 10?4 and ΔH = ?450 cal/mole for PBLA in m-cresol; σ = 0.6 × 10?4 and ΔH = 260 cal/mole for PBLA in chloroform containing 5.7 vol-% of dichloroacetic acid. This result gives evidence that σ may change not only from one polypeptide to another but also for a given polypeptide in different solvents. The change in limiting viscosity number [η] accompanying the transition was measured in the same solvents. The curve of [η] versus helical content had a relatively monotonic shape for the chloroformdichloroacetic acid solutions as compared with that for the m-cresol solutions, indicating that [η] depended largely on σ. Provided that [η] is a direct measure of the mean-square radius of gyration, 〈S2〉, the results are consistent with the theoretical predictions of Nagai and of Miller and Flory for 〈S2〉.  相似文献   
46.
Three types of tobacco (Nicotiana tabacum cv. Havana 38) callus: 1) healthy stem callus, 2) TMV-infected stem callus, 3) TMV-infected leaf callus; and leaves differentiated from healthy stem callus, and from TMV-infected leaf callus were compared for fine structure. In addition, the fine structure was observed of plastids in cells of leaves differentiated from callus isolated from stem sections of TMV-infected hybrid tobacco plants (N. tabacum cv. Havana 38 ×N. glutinosa) grown under high temperature. The cytoplasmic organelles in tissue cultured cells were similar to those in cells of greenhouse-grown tobacco plants. Except for plastids, TMV infection did not noticeably affect morphologically other cellular organelles in tissue culture cells. In TMV-infected leaf callus, numerous small bodies were seen in plastid-like bodies, while vesicle-like structures were observed in the stroma of plastids in leaves differentiated from callus of hybrid tobacco inoculated with TMV. Morphological variations of mitochondria, such as swelling and vacuolization of the inner matrix, occurred frequently in TMV-infected leaf callus. Needle-like crystalline inclusions or looped inclusions composed of many fine, long filaments were considered TMV particles orientated parallel to each other. The TMV particles were detected in the cytoplasm of tissue culture cells.  相似文献   
47.
48.
To gain a better understanding of growth curve, biomass duration in several growth models, such as the exponential, linear, Gompertz, Mitscherlich, logistic, Richards and Bertalanffy, is formulated. Generally, biomass duration in these models can be given in two ways; thet- andw-representations. The latter representation, which can be defined as the summed value of reciprocal of relative growth rate with respect to biomass, gives a new significance to biomass duration. The utility of both representations is exemplified by the observed data of a fir. The idea of biomass duration is extended to get total amounts of anabolism and catabolism in the Bertalanffy model.  相似文献   
49.
Summary In order to examine its clinical efficacy, recombinant human interferon- (rIFN-) was instilled intravesically into 51 patients with superficial bladder cancer. Ten patients, who received intermittent intravesical instillation at a dose of (3–36) × 106 U rIFN- on days 1–3 every week, showed no response. Thirty-two patients received intravesical instillation at a dose of (3–36) × 106 U every day for 10–20 days. Eight patients showed partial response, indicating an efficacy rate of 25%. Nine patients received divided doses of 18 × 106 U twice a day every day for 10–20 days. Six patients showed partial response, indicating an efficacy rate of 67%. This value was significantly higher than that obtained by administering divided doses. The response to intravesical instillation therapy with rIFN- varies with treatment protocol. Frequent and longer exposure to rIFN- may induce better regression of superficial bladder cancer. Six incidences of side-effects were found in five cases (9.8%): pollakiuria in one, pain on micturition in two, fever in two, and eruption in one case. All of these side-effects were slight and reversible after drug withdrawal. Laboratory tests showed only a few changes with low severity. Thus, rIFN- is potentially a new drug for instillation therapy of superficial bladder cancer, in view of the absence of adverse effects.  相似文献   
50.
Two different protease genes were cloned fromRhodocyclus gelatinosa APR 3-2 inEscherichia coli HB 101/ with pBR329 or its derivatives. The recombinant plasmids designated as pRP100 and pRP300 contained 11.2 and 10.6 kb DNA fragments, respectively. The differences of both plasmids in restriction enzyme maps indicate that these plasmids contained different protease genes. DNA fragments coding for protease, 6.4 kb and 4.5 kb from pRP100 and pRP300, were subcloned into pRP329 and designated as pRP101 and pRP301, respectively. The two cloned proteases were excreted in culture medium ofE. coli, and ß-lactamase ofE. coli, which was originally localized in periplasmic space, was also excreted in the medium.  相似文献   
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