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41.
Individual DNA identification from ancient human remains.   总被引:5,自引:2,他引:3       下载免费PDF全文
Individual identification of ancient human remains is one of the most fundamental requisites for studies of paleo-population genetics, including kinship among ancient people, intra- and interpopulation structures in ancient times, and the origin of human populations. However, knowledge of these subjects has been based mainly on circumstantial archaeological evidence for kinship and intrapopulation structure and on genetic studies of modern human populations. Here we describe individual identification of ancient humans by using short-nucleotide tandem repeats and mtDNAs as genetic markers. The application of this approach to kinship analysis shows clearly the presence or absence of kinship among the ancient remains examined.  相似文献   
42.
A capped cyclodextrin, 6-deoxy-6-(p-hydroxy-m-nitrophenacylthio)-β-cyclodextrin, was prepared in order to detect any conformational change of the host upon the guest binding. The association constant between the cyclodextrin and 1-adamantanecarboxylate, cyclohexanecarboxylate, p-methylbenzoate, 3,3-dimethylbutyrate, or 2,2-dimethylpropionate was enhanced 20, 5.3, 3.7, 2.3, or 2.0 times, respectively, by chromophore capping. The changes in the electronic, NMR, and circular dichroism spectra as well as pKa of this cyclodextrin upon binding of the guest strongly indicate a conformational change around the chromophoric moiety of the cyclodextrin.  相似文献   
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44.
Cytotoxic actions of various prostaglandins were examined on L1210 mouse leukemia and several human leukemia cell lines, and prostaglandin D2 (PGD2) was found most active. PGD2 exerted a dose dependent inhibition of L1210 cell growth over 3.6 μM. At 14.3 μM growth was completely inhibited, and the number of viable cells remarkably decreased during culture. Microscopically the remaining cells showed degenerative changes with many vacuoles in their cytoplasm. The IC50 value of PGD2 on L1210 cell growth was calculated to be 6.9 μM (2.4 μg/ml), and at this concentration the DNA synthesis in 24 hr cultured cells was also decreased to a half of the level in the control cells. Such growth inhibition by PGD2 was also found at similar concentrations with several human leukemia cell lines such as NALL-1, RPMI-8226, RPMI-8402, and Sk-Ly-16. Among other prostaglandins tested, PGA2 showed a comparable, and PGE2 a less but significant growth inhibitory activity, while PGB2, PGF and PGI2 had no such effects on cell proliferation at 14.3 μM concentration. These results suggest a potential antineoplastic activity of PGD2.  相似文献   
45.
Summary Changes in the lysosome structures were examined by electron microscopy during the formation of zoospores inTrebouxia potteri. Lysosomes in vegetative cells were homogeneously filled with electron-dense material. At the beginning of zoospore formation, lysosomes invaginated or evaginated to take up mitochondria, ER, or cytoplasmic ground plasma. The ingested organelles became disorganized within the lysosomes. During this disruption of these organelles, the lysosomal contents became heterogeneous, suggesting a decrease in the amount of enzymes within the lysosomes. Golgi bodies and ER seemed to be involved with the disruption of the organelles, probably supplying some substances necessary for the functioning of the lysosomes. Amount of electron-dense materials decreased and, finally, only one to three small spherical aggregates remained in the lysosomes. Then the lysosomes appeared to shrink via loss of watery substances or cutting off of electron-transparent regions. After these changes in lysosome structure, nuclei started to divide successively for formation of the zoospores. The possibility is proposed that the drastic cytoplasmic changes operated by lysosomes trigger the following morphogenetic events in the formation of zoospores.Abbreviations ER endoplasmic reticulum - TGN trans Golgi network  相似文献   
46.
The time of onset of the constrictive effect of indomethacin on the ductus arteriosus (DA) in fetal rats was assessed by measurement of the caliber of the DA after maternal treatment with indomethacin on days 19-21 of gestation. The day following overnight mating was regarded as day 0 of gestation. Observation was performed by direct exposure of the DA by hand shaving of intact frozen fetuses. On days 20 and 21, the DA was significantly constricted 3 h after maternal treatment with 1 mg/kg of indomethacin. When the DA was examined at 19 1/2 and 19 2/3 days of gestation (3 h after indomethacin exposure), it was significantly constricted at 19 2/3 days but not at 19 1/2 days. Higher doses of indomethacin (10 and 100 mg/kg) induced a significant constriction of the DA at day 19 1/2, but not at the beginning of the same day (1.00 a.m.). These results suggest that the onset of the susceptibility of the DA to the constrictive effect of indomethacin occurs in the first half of day 19 of gestation.  相似文献   
47.
In order to elucidate the substrate specificity of alanyl-tRNA synthetase, 5'-O-[N-(L-alanyl)sulfamoyl]adenosine (Ala-SA), an analogue of alanyl-AMP, was chemically synthesized. Its binding ability is similar to that of the substrate based on the inhibitory activity for the aminoacylation of alanyl-tRNA synthetase. Taking advantage of the stable sulfamoyl bond of Ala-Sa, compared with the highly labile aminoacyl bond of alanyl-AMP, the molecular conformation of the former inhibitor was studied by X-ray single crystal analysis. Crystal data are as follows: C13H19N7O7S.2H2O, space group C2, a = 39.620(6), b = 5.757(1), c = 20.040(3) A, beta = 117.2(1) degrees, V = 4065(9) A3, Z = 8, and final R = 0.065 for 2785 independent reflections of F(2)0 greater than or equal to 2 sigma (F0)2. In the crystal, the molecule is in a zwitterionic state with the terminal amino group protonated and sulfamoyl group deprotonated, and takes an open conformation, where the L-alanine moiety is located far from the adenosine moiety with gauche/trans and trans orientations about the exocyclic C(4')-C(5') and C(5')-O(5') bonds, respectively. The conformation of the adenosine moiety is anti for the glycosyl bond and C(3')-endo for the ribose puckering, and alanine is in the usually observed trans region for the psi torsion angle. The molecular dimensions of the sulfamoyl group are nearly the same as those of the phosphate group. The biological significance of the observed Ala-SA conformation is discussed in relation with the molecular conformation of tyrosyl-AMP complexed with tyrosyl-tRNA synthetase.  相似文献   
48.
An expression vector for G-CSF, pASLB3-3, was constructed and introduced into Namalwa KJM-1 cells (Hosoi et al., 1988), and cells resistant to 100 nM of methotrexate (MTX) were obtained. Among them, the highest producer, clone SC57, was selected and the productivity of this clone was further characterized. The maximal production of G-CSF was at the most 1.8 g/ml/day using a 25 cm2 tissue culture flask, even though the cell number was above 7×105 cells/ml. The limiting factors at high density were analyzed as the deficiency of nutrients, such as glucose, cysteine and serine, and pH control. The depression of specific G-CSF productivity per cell under the batch culture conditions was overcome by using a perfusion culture system, BiofermenterTM (Sato, 1983) with modifications of nutrients supplementation by a dialysis membrane and/or dissolved oxygen (DO) supplementation by microsilicone fibers. ITPSGF medium was modified to elevate concentrations of amino acids and glucose by 2.0- and 2.5-times, respectively. Under the control of pH at 7.4 and DO at 3 ppm, the specific G-CSF productivity was not depressed even at high cell density (above 1×107 cells/ml), and the amount of G-CSF reached 41 g/ml. These results indicated the possibility of finding the optimum culture conditions for the production of recombinant proteins by Namalwa KJM-1 cells.Abbreviations ABTS 2,2-Azino-di-(3-ethylbenzothiazoline)-6-sulfonic acid - BSA Bovine Serum Albumin - BSA-PBS Phosphate-buffered Saline without Ca2+ and Mg2+ containing Bovine Serum Albumin - dhfr Dihydrofolate Reductase - DO Dissolved Oxygen - G-CSF Granulocyte Colony-stimulating Factor - HEPES 4-(2-Hydroxyethyl)-1-piperazineethansulfonic Acid - IFN Interferon - MTX Methotrexate - PBS(-) Phosphate-buffered saline without Ca2+ and Mg2+ - Tween-PBS Phosphate-buffered saline without Ca2+ and Mg2+ containing 0.05% of Tween 20  相似文献   
49.
The xanthurenic acid-insulin complex was found to have similar immunological properties to native Zn-insulin. This complex showed less hormonal activity on glucose metabolism in adipose tissue than native An-insulin, but its activity was increased by addition of Zn2+ ions.  相似文献   
50.
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