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The need for selection of the optimal material for the manufacturing of cardio-patches can be resolved by the use of cryostored autologous pericardial tissue. This short communication is a concise fragment of a large-scale research and demonstrates only the efficiency of cell culturing before and after pericardial preservation in the low temperature conditions.  相似文献   
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A continuous-flow NMR culture system for mammalian cells has been developed on which 31P-NMR experiments under complete and strictly physiologic conditions have been performed. Observations on the response of the cellular metabolism to stresses such as starvation, low temperature and changes in environmental pH monitored by 31P-NMR are reported. The response of the intracellular pH relative to the external pH of the growth medium is studied. We find that under the experimental conditions used there exists a ΔpH varying between less than 0.2 and more than 0.6 pH units. These results are compatible with those obtained using other techniques.  相似文献   
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To expand the mink map, we established a new panel consisting of 23 mink-mouse clones. On the basis of statistical criteria (Wijnen et al. 1977; Burgerhout 1978), we developed a computer program for choice of clones of the panel. Assignments of the following mink genes were achieved with the use of the hybrid panel: glyoxalase (GLO), Chromosome (Chr) 1; acetyl acylase (ACY), Chr 5; creatine phosphokinase B (CKBB), Chr 10; alcohol dehydrogenase-2 (subunit B) (ADH2), Chr 8. Using a series of clones carrying rearrangements involving mink Chr 1 and 8, we assigned the gene for ME1 to the short arm of Chr 1 and that for ADH2 to Chr 8, in the region 8p12-p24. Mapping results confirm the ones we previously obtained with a mink-Chinese hamster panel. However, by means of an improved electrophoretic technique, we revised the localization of the gene for purine nucleoside phosphorylase (NP), which has been thought to be on mink Chr 2. It is reassigned to mink Chr 10.  相似文献   
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Regularities in the variation of chemical shifts and the glycosidation effects in the 13C-n.m.r. spectra of disaccharides were found to depend on the configuration at the anomeric centre of the glycosidating pyranose, and the absolute configuration of both pyranoses moieties. These empirical regularities are explained in terms of the spatial proton-proton interactions within the statistically averaged, or preferred, conformation near the glycosidic linkage. The applicability of these effects for the determination of the anomeric and absolute configuration and the sequence of pyranose residues in oligo- and poly-saccharides is discussed. The conformational properties of glycosidic linkages in disaccharides and disaccharide fragments of oligo- and poly-saccharides are compared on the basis of 13C-n.m.r. data.  相似文献   
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A Bence Jones protein with phenotype Inv (1, –2) was isolated from the urine of a patient with multiple myeloma. Inv typing of the patient's relatives established the presence of anInv 1 allele in the kindred, and that the patient's genotype wasInv 1/Inv 3. Hence, the absence of Inv (2) in the Bence Jones protein was shown to be genetic and not an artifact caused by the disease. The tryptic peptide-containing residues 191 through 194 were isolated and shown to be composed of Leu, Tyr, Ala, Cys, with Leu at the amino end. Hence, the residue at 191 is the same as that present in Inv (1, 2) Bence Jones proteins. More detailed study of the tryptic peptides established that residue 153 is Val rather than Ala as in all other K chains thus far studied. The primary sequence: Ala153, Leu191 determines Inv (1, 2); Ala153, Val191 determines Inv (3); and Val153, Leu191 determines Inv (1). The Val153, Val191 sequence has not been observed. It may correspond to Inv (–). These data are strikingly similar to the data for the Kern and Oz isotypes (changes at 154 and 191, respectively) in the chain. As in the case of theK chain, only three of the four possible combinations have been observed. The implications of this parallelism and of crystallographic findings on chains, reported by others, are discussed.  相似文献   
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A diagonal-electrophoresis method for the selective purification of serine phosphate peptides was applied to tryptic, chymotryptic and peptic digests of oxidized ovalbumin. This method is based on the release of the phosphate group bound to serine by treatment with alkaline phosphatase on paper. The identified serine phosphate peptides were purified by paper electrophoresis at pH6.5 and 2.0, dephosphorylation with bacterial alkaline phosphatase, and paper electrophoresis at pH2.0 again, in that order. The presence of two groups of serine phosphate peptides was apparent from the amino acid composition. One group contained no lysine, cysteic acid, proline, leucine or isoleucine (sequence 1) and the other had all those amino acids (sequence 2). Further degradation with subtilisin of those peptides and ;dansyl'-Edman sequence analysis established their partial sequences. The proposed sequences are as follows (with ;SerP' representing serine phosphate): sequence 1, -Ala-Gly-Arg-Glu-Val-Val-Gly-SerP-Ala-Glu-Ala-Gly-Asp-Val-Ala-Ala-Ser-(Val,Glx(2),Ser,Phe)-Arg-; sequence 2, -Asp-Lys-Leu-Pro-Gly-Phe-Gly-Asp-SerP-Ile-Glx-Ala-Glx-CySO(3)H-Gly-(Thr,Ser,Val)-(Asp,His,Val)-. The partial sequence of one of the phosphopeptides, Asp-(Glu,Ile,SerP), reported by Flavin (1954) was used to establish the proposed sequence 2.  相似文献   
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