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161.
Human fibroblastoid interferon produced from an established human cell line was purified by controlled-pore glass and concanavalin A-Sepharose column chromatography followed by preparative two-dimensional gel electrophoresis. The purification procedure provided a 10% recovery of pure interferon with good reproducibility. The purified protein was homogeneous with respect to its molecular weight of 20,000 and net electrical charge at pH 2.5. Interferon of high specific activity of 5 x 10(8) units/mg of protein was directly demonstrated in the polyacrylamide gel before staining with Coomassie brilliant blue. Parallel purification of a sham-induced interferon preparation did not yield an equivalent product indicating the purified interferon is not derived from uninduced cells or from the fetal calf serum of the tissue culture growth medium. Pure interferon was radioiodinated by Bolton-Hunter reagent. Amino acid analysis of the pure preparation shows interferon to be a leucine-rich glycoprotein containing a high percentage of glutamic/glutamine residues and that disulfide bridges(s) are important for its biological activity.  相似文献   
162.
Summary Kadazans, the largest indigenous group in Sabah, northern Borneo, were surveyed for glyoxalase I, phosphoglucomutase I, red cell acid phosphatase, esterase D, adenosine deaminase, soluble glutamate pyruvate transaminase, soluble glutamate oxaloacetate transaminase, 6-phosphogluconate dehydrogenase, uridine monophosphate kinase, adenylate kinase, peptidase B and D, superoxide dismutase, C5, group specific component, haptoglobin and transferrin.Kadazans were found to be polymorphic for GLOI, PGMI, RCAP, esterase D, ADA, s-Gpt, 6PGD, UMPK, Gc, C5, haptoglobin and peptidase B. Rare variants were found for transferrin and peptidase D. No variant was found for s-Got, SOD and AK.  相似文献   
163.
Offspring of control female rats received colostrum from females immune to Trypanosoma gambiense after birth. Subsequently, these offspring had high titers of agglutinating and phagocytosis-promoting activities in their sera. They were not protected against challenge infection, although a delay of parasitemia and extended survival were often observed. On the other hand, the offspring of immune females, which had received colostrum from control females after birth, showed low agglutinating and phagocytosis-promoting activities in their sera; 50% were protected against infection. It was concluded that antibodies (IgG) passing through the placenta of immunized females were more effective than antibodies (IgA) derived from colostrum from immunized females in protecting offspring against trypanosome infection. Phagocytosis-promoting activity was detected in both colostral IgA-rich fractions from the colostra of immunized females and serum IgA-rich fractions from the control females' offspring, which had received colostrum from immune females. Pepsin digestion resulted in the loss of such activity. It is possible that the phagocytosis-promoting activity of IgA antibodies was not present in the products obtained by means of pepsin treatment.  相似文献   
164.
During a 5-year period (Apr. 14, 1970 to Apr. 14, 1975) 930 patients underwent aortocoronary bypass grafting; the procedure was done as an emergency in 141. Of the entire group 3.3% died at operation, 1.6% died in hospital and 5.8% died later; of the patients undergoing emergency grafting 12.1% died at operation and 5.7% died later. From a detailed analysis of the first 600 patients it was found that both operative and late mortality were clearly related to two factors: severe left ventricular dysfunction at the time of operation and inadequate surgical treatment because of insertion of insufficient numbers of grafts or because of poor blood flow through the grafts.  相似文献   
165.
The phosphorylation of microtubular proteins isolated by reassembly in vitro from slices of guinea-pig cerebral cortex labelled with [32P]orthophosphate was investigated. Under the conditions tested, both and the alpha and beta forms of tubulin contained metabolically-active P which accounted for about one third of the total 32P incorporated into protein; the remaining protein-bound 32P was associated with 3-4 minor high MW components co-purifying with tubulin during two cycles of assembly-disassembly. Microtubular protein prepared in this way contained approx. 0.8 mol of alkalilabile P/mol of tubulin dimer (M.W. 110,000). In vitro studies showed that reassembled microtubular protein preparations catalysed the incorporation of up to 0.55 mol of P/mol of tubulin dimer during incubation with Mg2+ and [gamma 32P]ATP. The reaction was linear during the first 30 min of incubation at 37 degrees C. Cyclic AMP (10 microM, final concentration) caused a transient increase in the initial rates of tubulin phosphorylation. Little label was incorporated into the minor high M.W. components under these conditions. The in vitro phosphorylation of microtubular protein increased in a non-linear manner with respect to protein concentration: this was in contrast to earlier experiments showing linear kinetics when chromatographically isolated tubulin was tested for intrinsic kinase activity. Isolated microtubular protein preparations bound [3H]GTP, [3H]ATP and to a lesser extent, [3H]cyclic AMP, and exhibited Ca(2+)-ATPase activity (up to 60 pmol Pi released min/mg protein at 37 degrees C).  相似文献   
166.
Hypertonic medium selectively suppressed the synthesis of most host cell polypeptides relative to the synthesis of simian virus 40 capsid polypeptides and a minority of cellular polypeptides, notably histones. Under optimal hypertonic conditions, the synthesis of the major capsid polypeptide (VP1) is enhanced about sevenfold relative to host polypeptide synthesis. Because of the small amounts of the other nonhistone capsid polypeptides (VP2) and VP3) present in cell lysates, it was difficult to quantitate the extent, if any, of their enhancement. The maintenance of the restricted pattern of protein synthesis caused by hypertonic medium was dependent on continual peptide chain initiations. The resistance of viral protein synthesis to hypertonic conditions provides a means of detecting relatively low levels of intracellular viral protein synthesis. Analysis of the specific activity of the acid-soluble [3H]lysine pool indicated that the rate of incorporation of [3H]lysine into protein was an overestimation of the actual rate of overall protein synthesis occurring in cells exposed to hypertonic as compared to isotonic conditions. Since it is likely that both cellular and viral protein synthesis draw lysine from a single pool, this change in pool specific activity does not affect the analysis of relative rates of protein synthesis at a given level of tonicity.  相似文献   
167.
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169.

Background, aim, and scope  

Propagation of parametric uncertainty in life cycle inventory (LCI) models is usually performed based on probabilistic Monte Carlo techniques. However, alternative approaches using interval or fuzzy numbers have been proposed based on the argument that these provide a better reflection of epistemological uncertainties inherent in some process data. Recent progress has been made to integrate fuzzy arithmetic into matrix-based LCI using decomposition into α-cut intervals. However, the proposed technique implicitly assumes that the lower bounds of the technology matrix elements give the highest inventory results, and vice versa, without providing rigorous proof.  相似文献   
170.
1. The L-amino acid oxidase, hyaluronidase, alkaline phosphomonoesterase, protease, phosphodiesterase, acetylcholinesterase, phospholipase A and 5'-nucleotidase activities of 47 samples of venoms from all the six species of cobra (Naja), including five subspecies of Naja naja, were examined. 2. The results demonstrated interspecific differences in the venom contents of phospholipase A, acetylcholinesterase, hyaluronidase and phosphodiesterase. These differences in venom enzyme contents can be used for the differentiation of species of the genus Naja. 3. Thus, our results revealed a correlation between the enzyme composition of venom and the taxonomic status of the snake at the species level for the genus Naja.  相似文献   
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