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1.
2.
Jin Wei Mia Madel Alfajaro Peter C. DeWeirdt Ruth E. Hanna William J. Lu-Culligan Wesley L. Cai Madison S. Strine Shang-Min Zhang Vincent R. Graziano Cameron O. Schmitz Jennifer S. Chen Madeleine C. Mankowski Renata B. Filler Neal G. Ravindra Victor Gasque Fernando J. de Miguel Ajinkya Patil Huacui Chen Craig B. Wilen 《Cell》2021,184(1):76-91.e13
3.
Sharbati R. Singh Sunita Dalal Rohtas Singh A. K. Dhawan Rajwant K. Kalia 《Journal of plant biochemistry and biotechnology.》2012,21(2):220-228
Effect of season, media type, carbon source, growth regulators and transplanting media on micropropagation of Dendrocalamus asper, an important bamboo species, was examined. The season of explant collection played an important role in axillary bud sprouting and spring (February?CApril) was found to be the best period for explant collection. Among the different media MS was found to be the best for micropropagation. Maximum numbers (4.83/explant) of shoots were initiated in MS?+?15???M BAP. For shoot multiplication, MS medium supplemented with 10???M BAP and 75???M Adenine sulfate was used. BAP was superior to KIN for both explant establishment, as well as, shoot multiplication. Optimal rooting was achieved in shoots cultured on ? strength MS medium supplemented with 5???M each of IBA and NAA. Regenerated plantlets were acclimatized and hardened in green house using dune sand and vermi-compost (3:1) with 92.34% success and transferred to the field with 100% survival rate. In the field, plants supplied with FYM along with urea showed better growth and development. Macroproliferation, plant multiplication by separating the rooted tillers of well established in vitro raised plantlets after 5 to 6?months of growth in the green house could double the multiplication rate. More than 25000 in vitro raised plants were successfully transferred to the field and no morphological variations in growth were observed, thus proving the potential of tissue culture for raising large scale plantations of D. asper. 相似文献
4.
T Faraggiana D Villari J Jagirdar J Patil 《The journal of histochemistry and cytochemistry》1986,34(6):811-816
Lung alveoli are coated by a thin layer of extracellular material rich in anionic charges. The nature of this acid layer and its relationship to the phospholipid surfactant are not known. We investigated the possible presence of sialic acid groups by light and electron microscopy in tissues from normal fetal and adult lungs, using neuraminidase treatment followed by staining with the galactose-binding lectin from peanut, labeled with peroxidase. Our results showed that adult lung does not bear peanut lectin-reactive sites but that a very thin and distinct reactive layer becomes evident after neuraminidase treatment, especially on type II pneumocytes. In fetal lung, the entire surface of the developing respiratory tree is outlined by a strongly peanut lectin-reactive layer even if neuraminidase digestion is not performed. We conclude that the acid coat of the alveolar lining is in part composed of sialic acid residues and that sialic acid is added to the fetal lung as the alveoli mature. 相似文献
5.
A child with normal growth and development and the abnormal karyotype 46,XY,17ps, was analyzed using molecular probes localized to 17p13. The results indicated the presence of two copies of the probes YNZ22.1 (D17S5) and YNH37.3 (D17S28), previously shown to be deleted in all Miller-Dieker (MDS) patients studied. However, the patient was hemizygous for probe p144D6 (D17S34), which is absent in approximately 75% of the MDS patients. As the patient is active at 9 months of age, with no clinical signs of MDS, the results confirm that the absence of locus D17S34 does not lead to the phenotypic expression of MDS. Furthermore, this deletion should assist in defining the distal limits of this contiguous gene syndrome. 相似文献
6.
Ghan Shyam Lohiya Hubert Pirkle Hoan Nguyen Sunita Lohiya Tran Vuu 《The Western journal of medicine》1988,148(4):426-429
We reviewed records of all persons dying between 1979 and 1986 in eight California institutions for the mentally retarded. Autopsies had been done in 71% of the 1,181 deaths. Nine deaths were due to hepatocellular carcinoma, which invariably developed in carriers of hepatitis B surface antigen (HBsAg) and was fatal within four months of diagnosis. The mean age at death was 32.7 years. The incidence of hepatocellular carcinoma in HBsAg carriers was 140 times greater than in the US population. Persistent hepatitis B infection was probably etiologically related to hepatocellular carcinoma in this population, which is relatively free of exposure to other hepatocarcinogens. 相似文献
7.
Synthetic soluble (—)-dopa melanin was prepared in deuteriated buffer, pH 8, by autooxidation of the precursor. At 6 mM of the precursor, the incorporation was over 90%. The changes in the line width measurements of N-CH3 protons of enantiomers of ephedrine in the soluble melanin were quantified by NMR spectroscopy. The dissociation constants of (—)-1R,2S-ephedrine, (+)-1S,2R-ephedrine, (—)-1R,2R-ψ-ephedrine, and (+)-1S,2S-ψ-ephedrine were 11.7, 4.20, 3.60, and 4.80 mM, respectively. Since the concentration of (—)-dopa was known and since the conversion of (—)-dopa to indole units of melanin was considered as 1:1, the stoichiometry of the interaction between the drug and the indole unit was calculated. Based on the dissociation constants of the enantiomers, it appears that up to four molecules of (—)-ephedrine can interact with one indole unit of the melanin, while such a ratio for other isomers appear to be 2:1. The preference by indole units of melanin is stereoselective. © 1992 Wiley-Liss, Inc. 相似文献
8.
EPR-detectable redox centers of the periplasmic hydrogenase from Desulfovibrio vulgaris 总被引:1,自引:0,他引:1
D S Patil J J Moura S H He M Teixeira B C Prickril D V DerVartanian H D Peck J LeGall B H Huynh 《The Journal of biological chemistry》1988,263(35):18732-18738
The periplasmic hydrogenase of Desulfovibrio vulgaris (Hildenbourough NCIB 8303) belongs to the category of [Fe] hydrogenase which contains only iron-sulfur clusters as its prosthetic groups. Amino acid analyses were performed on the purified D. vulgaris hydrogenase. The amino acid composition obtained compared very well with the result derived from the nucleotide sequence of the structural gene (Voordouw, G., Brenner, S. (1985) Eur. J. Biochem. 148, 515-520). Detailed EPR reductive titration studies on the D. vulgaris hydrogenase were performed to characterize the metal centers in this hydrogenase. In addition to the three previously observed EPR signals (namely, the "isotropic" 2.02 signal, the rhombic 2.10 signal, and the complex signal of the reduced enzyme), a rhombic signal with resonances at the g-values of 2.06, 1.96, and 1.89 (the rhombic 2.06 signal) was detected when the samples were poised at potentials between 0 and -250 mV (with respect to normal hydrogen electrode). The midpoint redox potentials for each of the four EPR-active species were determined, and the characteristics of each EPR signal are described. Both the rhombic 2.10 and 2.06 signals exhibit spectral properties that are distinct from a ferredoxin-type [4Fe-4S] cluster and are proposed to originate from the same H2-binding center but in two different conformations. The complex signal of the reduced hydrogenase has been shown to represent two spin-spin interacting ferredoxin-type [4Fe-4S]1+ clusters (Grande, H. J., Dunham, W. R., Averill, B., Van Dijk, C., and Sands, R. H. (1983) Eur. J. Biochem. 136, 201-207). The titration data indicated a strong cooperative effect between these two clusters during their reduction. In an effort to accurately estimate the number of iron atoms/molecule of hydrogenase, plasma emission and chemical methods were used to determine the iron contents in the samples; and four different methods, including amino acid analysis, were used for protein determination. The resulting iron stoichiometries were found to be method-dependent and vary over a wide range (+/- 20%). The uncertainties involved in the determination of iron stoichiometry are discussed. 相似文献
9.
Redox titrations of the iron-sulphur clusters in fumarate reductase purified from Escherichia coli, monitored by ESR spectroscopy, identified three redox events, similar to those observed in other fumarate reductases and succinate dehydrogenases: Centre 1, a [2Fe-2S] cluster, at g = 2.03, 1.93, appeared on reduction with Em = -20 mV. Centre 3, probably a [3Fe-xS] cluster, at g = 2.02 appeared in the oxidized state with Em = -70 mV. Centre 2 has been observed as an increase in the electron-spin relaxation of Centre 1. It titrates as an n = 1 species with Em = -320 mV, but in our hands did not appear to contribute significant intensity to the g = 2.03, 1.93 signal. It therefore appears to be an additional centre which undergoes spin-spin interaction with Centre 1. The reduction of Centre 2 coincided with the appearance of an extremely broad ESR spectrum, observed at temperatures below 20 K, with features at g = 2.17, 1.9, 1.68. The broad signal was observed in both soluble and membrane-bound preparations. Its midpoint potential was -320 mV. Its integrated intensity was approximately equal to that of Centre 1, if its broad outer wings were taken into account. Consideration of the ESR properties of this signal, together with the amino acid sequence of the frdB subunit of the enzyme, indicates that Centre 2 is a [4Fe-4S] cluster which, in its reduced state, enhances the spin relaxation of the [2Fe-2S] Centre 1. 相似文献
10.