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51.
Effect of fructose on glycogen synthesis in the perfused rat liver   总被引:1,自引:0,他引:1  
The effect of fructose on glycogen synthesis was examined in the perfused liver of starved rats. With increasing fructose concentration in the perfusate, glycogen synthesis and the % a form of glycogen synthase increased to a maximum at 2 mM and then decreased, progressively. The glucose 6-P level increased with the increase in fructose concentration. On the other hand, the ATP content was unchanged at a concentration of 2 mM or less and decreased at 3 mM or more. We also showed that the stimulation of glycogen synthesis by fructose at a concentration of 2 mM or less was due to activation of glycogen synthase by accumulated glucose 6-P and that ATP depletion at a concentration of 3 mM or more caused an increase in phosphorylase a and a decrease in glycogen synthase activity even in the presence of a high concentration of glucose 6-P.  相似文献   
52.
In order to expand tumor-infiltrating lymphocytes (TIL) efficiently and in order to use them for immunotherapy, we utilized lipopolysaccharide-activated B cells (LPS blasts) as costimulatory-signal-providing cells in an in vitro culture system. TIL, prepared from subcutaneously inoculated B16 melanoma, failed to expand when cultured with anti-CD3 monoclonal antibody (mAb) alone followed by a low dose of interleukin(IL)-2. In contrast, such TIL did expand efficiently in culture with both anti-CD3 mAb and LPS blasts followed by culture with IL-2. These findings suggest that the presence of LPS blasts in the initial culture was essential for the cell expansion. The expansion of TIL was partially blocked by the addition of CTLA4 Ig, which is an inhibitor of costimulatory molecules such as CD80 and CD86, and was almost blocked by the addition of anti-(Fc receptor II)mAb. These findings thus indicate that such molecules, in conjunction with the receptor on the LPS blasts, participate in the efficient expansion of TIL. The B16-derived TIL, which expanded in our culture system, were predominantly CD8+T cells and showed a higher level of cytolytic activity against B16 melanoma than either lymphokine-activated killer cells or TIL cultured with a high dose of IL-2. In addition, the in vitro expanded B16-derived TIL produced interferon , but not IL-4, in response to B16 melanoma. What is more important, the adoptive transfer of such TIL had a significant antitumor effect against pulmonary metastasis in B16 melanoma, even without the concurrent administration of IL-2. Collectively, our results thus indicate the therapeutic efficacy of the protocol presented here for antitumor immunotherapy with TIL.This work was supported in part by a grant from the Ministry of Education, Science and Culture  相似文献   
53.
Abstract The untranslatable, RNA polymerase II-dependent gene ( dutA ) of Dictyostelium discoideum is induced early in development. However, unlike other early genes, dutA induction was not affected by cAMP pulses and occurred normally in various cAMP-related mutant cells, the results indicating that this induction depended solely on factors other than cAMP. In the knockout strain of the catalytic subunit of protein kinase A, dutA expression was severely blocked and not recovered by cAMP pulses. This demonstrates that even the cAMP-independent gene, dutA , requires protein kinase A for its expression.  相似文献   
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Abstract. The co-occurrence of Larix olgensis var. changpaiensis, Picea jezoensis and Abies nephrolepis in the coniferous forest of Mount Changbai, northeastern China, is discussed, and the regeneration pattern of these taxa compared on the basis of the analysis of the age structure and the age-height relationship of the three conifers. The presence of tall individuals (ca. 30 m in height) of Larix olgensis var. changpaiensis, which does not show any regeneration, was related to the large eruption of Mount Changbai up to ca. 400 yr ago. Picea jezoensis compensates its small recruitment by a large stem size and long life span together with a continuous height growth. Abies nephrolepis recruits well, but its small stem size and short life span do not result in its dominance in the forest.  相似文献   
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Most ofthe human Not I linking clones identified to date areconsidered to be derived from CpG islands because ofthe recognitionsequence of this enzyme, and CpG islands have been reportedto be located around the 5' regions of genes. As a pilot study,we determined the complete nucleotide sequence (41,924 bp) ofa human cosmid clone (LL21NC02Q7A10) containing the marker D21S246originating from a Not I linking clone. As a result of sequenceanalysis, we successfully mapped and revealed the genomic genestructure for KIAA0002 previously reported as a cDNA clone.This gene consists of 15 exons and was shown to exist at theD21S246 locus on human chromosome 21q21.3–q22.1. Theseresults demonstrated that genomic marker-anchored DNA sequencingis a useful approach for the human genome project.  相似文献   
59.
The expression of two regeneration-associated antigens in the blastemas of normal and retinoid-treated regenerating limbs of axolotl ( Ambystoma mexicanum ) was examined.
One antigen, 55C12, which was similar to tenascin in expression pattern and molecular weight profile, was weakly expressed in the perichondrium and tendon of normal limbs. In the regenerating limbs, the amount of 55C12 antigen increased near the amputation site within 7 days and almost all cells of the blastema mesenchyme came to be positive to the antigen at 20 days, although those of epidermis and most stump tissues were negative. When the regenerating limbs were treated with Am80, a synthetic retinoid, which induced proximo-distal duplication, the expression of 55C12 antigen in the blastema became weak temporarily and was reactivated in the anterior region of the blastema. This expression pattern suggests that the duplicated limb is formed by the preferential growth of this 55C12-positive anterior blastema region.
The other antigen, 117C1, was faintly expressed in the epidermis, dermis, muscle, perichondrium and cartilage of normal limbs, and intensely expressed in the blastema mesenchyme and wound epidermis. The Am80 treatment, however, induced no changes in the expression pattern of 117C1.
These results suggest that these antigens may distinguish two different regions of the blastema in normal regeneration and retinoid-induced duplication.  相似文献   
60.
We examined serum copper (Cu), serum zinc (Zn), and the serum copper/zinc ratio (Cu/Zn) in 162 patients. All of them were seen to have an abnormal shadow in the chest X-ray films, that is, 109 patients with lung cancer (LC) and 53 patients with no lung cancer (NLC). The mean Cu and Cu/Zn in LC patients were significantly higher than those in NLC patients (p<0.05). In LC patients, Cu and Cu/Zn were higher and Zn was lower in advanced tumors than early ones. There was a significantly clear relation between Cu or Cu/Zn and the tumor (T) stages. When the relative risk (RR) of LC was estimated, it was seen that the higher Cu and Cu/Zn became, the higher RR became. Furthermore, we showed the sensitivity of the receiver operator characteristic of the test (ROC) curve for Cu, Cu/Zn, and carcinoembryonic antigen (CEA) to diagnose LC, as explained in a paragraph of methods.The determinations of Cu, Zn, and Cu/Zn are simple and inexpensive. They also appear to have a great diagnostic value in determining the local invasion of LC and as a screening test in the high-risk patients for LC.  相似文献   
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