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41.
The effect of an analog of LH-RH, (Des-Gly-NH210, Proethylamide9)-LH-RH, on LH release, was studied in one bull with azooapermia, and one cow with cystic follicle. The single intravenous injection of 100 μg LH-RH analog caused abrupt and marked increase in serum LH and the high levels of LH were maintained for 3 hours. The highest levels of serum LH were 48 and 114 times as high as the pre-treatment levels in a bull and a cow, respectively. Further studies are being undertaken to evaluate this compound for improving reproductive function in cattle. 相似文献
42.
Localization of 6S component of a alpha-actinin at Z-band 总被引:29,自引:0,他引:29
43.
Norimichi Kan Takashi Okino Masaki Nakanishi Kohei Satoh Kazuhisa Ohgaki Takayoshi Tobe 《Cancer immunology, immunotherapy : CII》1989,28(4):260-266
Summary The synergistic antitumor effect of interleukin-2(IL-2)-cultured tumor-bearer spleen cells (cultured lymphocytes) and immune fresh spleen cells was examined. Tumor-bearer cultured lymphocytes were obtained by culturing BALB/c spleen cells from syngeneic MOPC104E-tumor-bearing mice for 11 days with crude IL-2 and a soluble tumor extract. These cultured lymphocytes had weak antitumor activity when transferred i.p. into tumor-bearing mice that had been inoculated i.p. with 105 tumor cells 5 days previously. Immune fresh spleen cells, obtained from mice in complete remission after the treatment with cyclophosphamide, also had weak antitumor activity when transferred at the same schedule. The cultured cells and the fresh cells, mixed together before transfer, significantly augmented the therapeutic effect. At least 1×107 tumor-bearer cultured lymphocytes and 4×107 immune cells were needed for the synergistic effect. A tumor-specific combination was needed for both cultured and fresh cells. The effective subpopulation of tumor-bearer cultured lymphocytes was a cytotoxic one from an Lyt2+ precursor, and that of the immune fresh spleen cells was noncytotoxic, Lytl+ and Lyt2+ T-cells.A similar synergistic effect was also observed during in vitro coculture of tumor-bearer and immune cells. Cytotoxicity, as assessed by the 51Cr-release test, of tumor-bearer IL-2-cultured lymphocytes was maintained most effectively after 3 or 4 days of culture without IL-2 when the lymphocytes were cocultured with immune fresh spleen cells and tumor cells. 相似文献
44.
To study the molecular structure of the gene responsible for a lens fiber cell beaded-filament structural protein of 94kDa (CP94), we isolated its specific cDNA from a rat lens cDNA library by use of anti-mouse CP94 antiserum. The expressed fusion protein kept the epitopes specific against anti-chick CP97 as well as anti-mouse CP94 antibody, and the size was estimated as 190-200kDa, indicating that the cDNA insert of the clone seemed to encode a polypeptide with 80-90kDa in appearance. Northern analysis indicated that CP94 mRNA is expressed only in the lens, and not in the brain, skin, heart, kidney, lung, and liver, and the size was estimated to 2.1-2.3kb. In a lens of inherited microphthalmic mouse, Elo, a trace amount of mRNA with the size closely similar to that of rat mRNA was observed. The entire compiled sequence (1,873bp) showed an open reading frame covering the sequence of 533 amino acids totalling 58,857Da. No sequence homologous to the entire CP94 was found among the entries of any nucleotide and amino acid sequence databases; but with respect to a limited amino acid sequence of N-side region of CP94, a significant homology with cytokeratins was found. 相似文献
45.
By performing 1H-1H and 1H-15N two-dimensional (2D) nuclear magnetic resonance (NMR) experiments, the complete sequence-specific resonance assignment was determined for the colicin E3 immunity protein (84 residues; ImmE3), which binds to colicin E3 and inhibits its RNase activity. First, the fingerprint region of the spectrum was analyzed by homonuclear 1H-1H HOHAHA and NOESY methods. For the identification of overlapping resonances, heteronuclear 1H-15N (HMQC-HOHAHA, HMQC-NOESY) experiments were performed, so that the complete 1H and 15N resonance assignments were provided. Then the secondary structure of ImmE3 was determined by examination of characteristic patterns of sequential backbone proton NOEs in combination with measurement of exchange rates of amide protons and 3JHN alpha coupling constants. From these results, it was concluded that ImmE3 contains a four-stranded antiparallel beta-sheet (residues 2-10, 19-22, 47-49, and 71-79) and a short alpha-helix (residues 31-36). 相似文献
46.
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
47.
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49.
Omirulleh Serik Ismagulova Ainur Karabaev Murat Meshi Tetsno Iwabuchi Masaki 《Plant cell reports》1996,16(3-4):133-136
We have demonstrated that foreign DNA can be delivered into cells of mature embryos of wheat (Triticum aestivum L.) using silicon carbide fibers (SCF). The highest transient expression of thegusA (GUS) gene was detected when dry embryos were vortexed for 10–30 min in a SCF-DNA solution containing 90–120 g/l of sucrose. Up to 100 (on average 20–40) blue expression units per embryo were observed. Scutellum side and epiblast of the intact wheat embryos are preferentially transformed. When embryos with the coleoptilar tip removed were treated and allowed to germinate, GUS staining was observed in emerging leaf tissues. The potential of this new approach for stable transformation of wheat is under investigation. It has been found that callus tissues induced from the SCF treated embryos contain GUS-expressing sectors one month after treatment. 相似文献
50.
Cloning, sequencing, and expression of thermophilic Bacillus sp. strain TB-90 urease gene complex in Escherichia coli. 总被引:14,自引:9,他引:5 下载免费PDF全文
The urease of thermophilic Bacillus sp. strain TB-90 is composed of three subunits with molecular masses of 61, 12, and 11 kDa. By using synthetic oligonucleotide probes based on N-terminal amino acid sequences of each subunit, we cloned a 3.2-kb EcoRI fragment of TB-90 genomic DNA. Moreover, we cloned two other DNA fragments by gene walking starting from this fragment. Finally, we reconstructed in vitro a 6.2-kb DNA fragment which expressed catalytically active urease in Escherichia coli by combining these three DNA fragments. Nucleotide sequencing analysis revealed that the urease gene complex consists of nine genes, which were designed ureA, ureB, ureC, ureE, ureF, ureG, ureD, ureH, and ureI in order of arrangement. The structural genes ureA, ureB, and ureC encode the 11-, 12-, and 61-kDa subunits, respectively. The deduced amino acid sequences of UreD, UreE, UreF, and UreG, the gene products of four accessory genes, are homologous to those of the corresponding Ure proteins of Klebsiella aerogenes. UreD, UreF, and UreG were essential for expression of urease activity in E. coli and are suggested to play important roles in the maturation step of the urease in a co- and/or posttranslational manner. On the other hand, UreH and UreI exhibited no significant similarity to the known accessory proteins of other bacteria. However, UreH showed 23% amino acid identity to the Alcaligenes eutrophus HoxN protein, a high-affinity nickel transporter. 相似文献