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W Tymiński E Czestochowska A Hellmann A Kreglewski 《Folia haematologica (Leipzig, Germany : 1928)》1980,107(2):269-272
Coagulation and fibrinolysis were measured in the portal and peripheral circulation in 15 rabbits after ligation of the superior mesenteric artery. It was found that the local coagulation syndrome in the mesenteric region can be recognized by tests in blood samples taken from the peripheral circulation area. 相似文献
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H J Gabius A Bardosi S Gabius K P Hellmann M Karas H Kratzin 《Biochemical and biophysical research communications》1989,163(1):506-512
A Ca2+-dependent sialic acid-binding protein was purified on fetuin-Sepharose from various types of human tissue. The molecular mass was determined to be 10,315 Da by laser desorption mass spectrometry. Partial sequence analysis after cyanogen bromide cleavage that yielded one N-terminus accessible for Edman degradation revealed an identity to an internal stretch following the only methionine residue within a putative amino acid sequence (Mr 10,048), deduced from the cDNA of a cell cycle-specific gene. The reported biochemical identification is a prerequisite to infer the biological role of the so far undetected gene product. Initial glycohistochemical studies with sialic acid-(BSA-biotin) raised evidence for nuclear localization of sialic acid-binding sites that might reflect, at least in part, detection of this protein. 相似文献
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Dieter Ehlers Ina Sakowski Werher Mohrig 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1989,159(4):481-489
Summary The high affinity of granulocytes of guinea pig and man to glass surfaces is modified by serum. Native serum contains both an adherence-promoting activity, which is related to complement, and components which reduce the adhesiveness of granulocytes. These components are stable at 56°C for 30 min and are tightly bound to the glass surface. -Lipoproteins are candidates for this adherence reducing ability of serum. Adherence promotion by native serum is mediated by coating the glass surface with C3b/C3bi. Human granulocytes from the peripheral blood adhered to glass surfaces coated by native human or guinea pig serum with C3b/C3bi to almost the same extent as in the presence of native serum, but on guinea pig granulocytes elicited in the peritoneal cavity, a cell surface metalloproteinase degraded the C3b/C3bi, thus reducing the adhesiveness of these cells. This proteinase was inhibited by MgEDTA, DTT, and 1,10-phenanthroline, whereby the high adhesiveness of granulocytes was restored to C3b/C3bi-coated glass.Abbreviations
BA
benzamidine hydrochloride
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BTS
Bacillus thuringiensis subtoxicus
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DTT
dithiothreitol
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EAC
-amino-caproic acid
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gp
guinea pig
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LDL
low density lipoproteins
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SEM
scanning electron microscopy 相似文献
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Jessica E. Hoogendijk Gerard W. Hensels Ina Zorn Linda Valentijn Emiel A. M. Janssen Marianne de Visser David F. Barker Bram W. Ongerboer de Visser Frank Baas Pieter A. Bolhuis 《Human genetics》1991,88(2):215-218
Summary Recently, it has been shown that Charcot-Marie-Tooth disease type 1a (CMT1a) is linked with a duplication of a DNA segment that is detected by probe VAW409R3, and that is located on chromosome 17p11.2. Here, we show that this duplication also contains VAW412R3a, but not A10-41 and EW503. Accounting for the duplication in recombination analysis, we found recombinants between CMT1a and EW301 and EW502, but not with A10-41, VAW409R3, and VAW412R3. Using pulsed-field gel electrophoresis analysis, we estimated the minimal size of the duplicated region in CMT1a patients to be 1100 kb. 相似文献
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Recombinant human interleukin 1 alpha: purification and biological characterization 总被引:29,自引:0,他引:29
U Gubler A O Chua A S Stern C P Hellmann M P Vitek T M DeChiara W R Benjamin K J Collier M Dukovich P C Familletti 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(7):2492-2497
Interleukin 1 (IL 1) is a polypeptide hormone produced by activated macrophages that affects many different cell types involved in immune and inflammatory responses. The cloning and expression of a murine IL 1 cDNA in Escherichia coli encoding a polypeptide precursor of 270 amino acids has been reported, and expression of the carboxy-terminal 156 amino acids of this precursor in E. coli yields biologically active IL 1. By using the murine IL 1 cDNA as a probe, we have isolated its human homolog from cDNA generated to lipopolysaccharide-stimulated human leukocyte mRNA. Nucleotide sequence analysis of this cDNA predicts a protein of analysis of this cDNA predicts a protein of 271 amino acids (termed IL 1 alpha) which shows congruent to 61% homology to its murine counterpart but only 27% homology to a recently characterized human IL 1 precursor (IL 1 beta). We have expressed the carboxy-terminal 154 amino acids of IL 1 alpha in E. coli, purified this protein to homogeneity, and have compared it with pure recombinant murine IL 1 in several different IL 1 assays based on murine and human cells. Recombinant IL 1 is capable of stimulating T cell and fibroblast proliferation and inducing fibroblast collagenase and prostaglandin production, thus proving that a single molecule has many of the activities previously ascribed to only partially purified IL 1 preparations. Our results indicate that there exists a family of at least two human IL 1 genes (alpha and beta) whose dissimilar protein products have similar biological activities. 相似文献
10.
Protoplasten aus Zellkulturen vonDaucus carota 总被引:1,自引:1,他引:0
Summary Treatment of long-term tissue cultures of carrots and of adventive embryos in these cultures with Cellulase Onozuka P 1500 and with this enzyme + Macerocym resulted in high yields of protoplasts which could be cultivated over prolonged periods (up to 5 months) in a synthetic medium + 0.6 m sorbitol. During cultivation the size of the protoplasts increased considerably ( up to 10 times) and a high percentage of multinucleate (between 2 and 13 nuclei) protoplasts were formed. However no fusion and no regeneration of cell walls were observed. 相似文献