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171.
172.
Myelin inhibitory ligands of the Nogo-66 receptor (NgR1) limit axon regeneration in the adult CNS. Recent findings have identified additional co-receptors (functional homologues) of the trimeric NgR1 complex, post-translational modifications of the co-receptors within the cell membrane and novel Ca(2+)-dependent cytoplasmic-protein phosphorylation mechanisms. Such unique signalling pathways provide the potential to transduce myelin-derived growth inhibitory signals to the axonal cytoskeleton, and have been areas of intense investigation in recent years. Here, we summarize current understanding of the molecular basis of myelin-derived axon-growth inhibition in the CNS. 相似文献
173.
Present study was carried out in order to explore the ability of a bone graft-decalcified as well as fluoridated to form new bone when put in the rectus abdominis muscle of rabbit. A total of 66 implants placed inside the pouches created in rectus abdominis muscle of rabbits were followed for 2 to 20 weeks. Radiologically decal implants formed bone in 74% cases and fluoridated implants in 68%; whereas histologically 86% of decalcified and 80% of fluoride impregnated decal bone matrix showed evidence of bone induction. It is concluded that fluoride impregnation does not enhance the osteogenic potential of a decal bone matrix. 相似文献
174.
A relatively rapid five-step procedure was used in purifying to apparent homogeneity the glutamine synthetase from roots and one form of the enzyme (GSI) from leaves of rice. The steps were: preparation of crude extracts, ammonium sulfate precipitation, filtration on Sepharose 4B, fractionation on DEAE-Sephadex A25, and affinity chromatography on ADP-Sepharose 4B. The purified protein appeared as a single band on polyacrylamide gel electrophoresis. Leaf GSI and the second type of leaf glutamine synthetase (GSII) formed distinct peaks when eluted from DEAE-Sephadex (step 4). The root enzyme and leaf GSI were similar in all the properties which were examined. Both enzymes bound to ADP-Sepharose, had similar biosynthetic (18 μmol P/img protein/min) and transferase (1324 and 1156 μmol γ-glutamyl hydroxamate/mg protein/min) activities, and the same or nearly the same Km values for glutamate (2.17 mm), Mg2+ (4.5 and 5.0 mm), ATP (286 μm), NH4+ (210 and 135 μm), and ADP (3.8 and 5.3 μm). In contrast, leaf GSII did not bind to ADP-Sepharose and had much higher Km values for glutamate (8.3 mm), Mg2+ (15 mm), NH4+ (684 μm), and ADP (33 μm). 相似文献
175.
A large osteoperiosteal gap was created in rabbit's ulna. A total of 18 allogenic decalbone grafts in left ulnar gap and 20 autoclaved allogenic decalbone grafts on right ulnar gaps were implanted. Five gaps were left unbridged to serve as controls. The results were assessed by clinical, radiological, macroscopic, histological and tetracycline fluorescent studies. It is observed that whereas the decalbone can successfully bridge a large gap in a vast majority of cases; the standard autoclaving of decalbone denatures its proteins which melt and cover the outer surface. The union, incorporation and remodelling of autoclaved decalbone grafts are slower as compared to that with unautoclaved decalbone. 相似文献
176.
J R Paddison T P Haromy M Sundaralingam R W Myers J N BeMiller 《Carbohydrate research》1987,168(1):7-13
The title compound (C8H12N2O6) crystallizes in the orthorhombic space group P2(1)2(1)2(1) (Z = 4), with a = 4.871(1), b = 11.136(2), c = 18.301(2) A. The structure was solved by the multi-solution technique and refined by full-matrix least-squares to a final R-index of 0.042. The compound adopts the 4C1(D) conformation. Bond lengths in the diazoacetyl group are consistent with the presence of a zwitterion. 相似文献
177.
Toxic Metal and Trace Element Concentrations in Blood and Outcome of In Vitro Fertilization in Women
Tulić Lidija Vidaković Snezana Tulić Ivan Ćurčić Marijana Bulat Zorica 《Biological trace element research》2019,188(2):284-294
Biological Trace Element Research - The aim of this study was to investigate the association of trace element and toxic metal concentrations in blood and the outcome of in vitro fertilization... 相似文献
178.
The nonheterocystous filamentous CyanobacteriumPlectonema boryanum strain UTEX 594 contains at least two plasmids. A small 145 kb plasmid was cloned in pBR322. It has no homology with the
bigger resident plasmid or with chromosomal DNA. A small fraction of the plasmid is present in the form of multimers or concatemers.
Copy number and hybridization patterns of the plasmid were similar under dinitrogen-fixing and non-fixing conditions. Restriction
site mapping of the plasmid was done to enable its use in the development of cyanobacterial cloning vectors. It is among the
smallest natural plasmids reported from bacteria. 相似文献
179.
Amit Tuli Mahak Sharma Xiaojian Wang Laura C. Simone Haley L. Capek Steven Cate William H. Hildebrand Naava Naslavsky Steve Caplan Joyce C. Solheim 《Cancer immunology, immunotherapy : CII》2009,58(9):1419-1431
Amyloid precursor-like protein 2 (APLP2) is a ubiquitously expressed protein. The previously demonstrated functions for APLP2
include binding to the mouse major histocompatibility complex (MHC) class I molecule H-2Kd and down regulating its cell surface expression. In this study, we have investigated the interaction of APLP2 with the human
leukocyte antigen (HLA) class I molecule in human tumor cell lines. APLP2 was readily detected in pancreatic, breast, and
prostate tumor lines, although it was found only in very low amounts in lymphoma cell lines. In a pancreatic tumor cell line,
HLA class I was extensively co-localized with APLP2 in vesicular compartments following endocytosis of HLA class I molecules.
In pancreatic, breast, and prostate tumor lines, APLP2 was bound to the HLA class I molecule. APLP2 was found to bind to HLA-A24,
and more strongly to HLA-A2. Increased expression of APLP2 resulted in reduced surface expression of HLA-A2 and HLA-A24. Overall,
these studies demonstrate that APLP2 binds to the HLA class I molecule, co-localizes with it in intracellular vesicles, and
reduces the level of HLA class I molecule cell surface expression. 相似文献
180.
In vitro proliferation of shoots and regeneration of cotton 总被引:3,自引:0,他引:3
Gupta Shiv K. Srivastava Alok K. Singh Pradhyumna K. Tuli Rakesh 《Plant Cell, Tissue and Organ Culture》1997,51(2):149-152
Shoot proliferation from different explants of several Indian cultivars of cotton was studied in culture. Cotyledonary nodes
taken along with the shoot apex of seedlings produced multiple shoots on modified MS nutrient agar supplemented with cytokinins.
6-Benzyladenine was most effective in inducing growth of multiple shoots. Explants of several genotypes formed organogenic
masses that differentiated to secondary shoots on repeated subculture. The isolated shoots were rooted on basal medium supplemented
with naphthaleneacetic acid and were transferred to soil after acclimatization.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献