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1.
The induction of antimicrobial activity of a new preparation, an aqueous fraction of water-oil emulsion oxidized by air oxygen, was studied. The effect of various factors (the degree of unsaturation of the initial oil and the content of oil oxidation products in obtained preparation) on the antimicrobial activity was determined. The antimicrobial activity of the preparation was induced by oil oxidation. The preparation produced from sardine Sardinops melanostica oil (33.95% of polyunsaturated fatty acids) displayed the highest antimicrobial activity. The antimicrobial activity was shown in water-soluble oil oxidation products.  相似文献   

2.
3.
The effect of a dsRNA preparation (an interferon inductor) on DTH induced by SRBC was studied. It was shown that at optimal antigenic load the dsRNA preparation inhibited DTH whereas at suboptimal and supraoptimal loads the preparation stimulated it. The findings indicated that the dsRNA preparation had an immunoregulatory effect. The immunoregulatory properties of the preparation must be associated with its action on the lymphocyte suppressor cells and macrophages.  相似文献   

4.
Photosystem II oxygen-evolving preparations with attached phycobilisomes were isolated from the thermophilic cyanobacterium Synechococcus sp. with beta-octylglucoside or digitonin. Fluorescence emission spectra of the two preparations determined at 77 K largely lacked a far red band which originates from photosystem I. The spectrum of the digitonin preparation was otherwise similar to that of intact cells, whereas the beta-octylglucoside preparation showed a pronounced band at 687 nm, which is considered to be emitted from phycobilisomes. The relative yield of phycobilin fluorescence was similar between the digitonin preparations and the cells but was considerably larger in the beta-octylglucoside preparations at room temperature. The quantum yield of ferricyanide photoreduction determined with light which is absorbed mainly by phycobiliproteins was 0.85 for the digitonin preparation and 0.57 for the beta-octylglucoside preparation. The results indicate that excitation energy is transferred from phycobilisomes to photosystem II reaction centers in the digitonin preparation as efficiently as in intact cells, while a significant portion of light energy harvested by phycobilisomes is not utilized by the primary photochemistry in the beta-octylglucoside preparation. Digitonin and beta-octylglucoside preparations had 65 and 48 chlorophyll a molecules per photosystem II reaction center, respectively. The beta-octylglucoside preparation contained twice as much phycocyanin and allophycocyanin per photosystem II reaction center as the digitonin preparation, which has a phycobiliprotein-to-photosystem II reaction center ratio very similar to that of cells. It is concluded that whereas the beta-octylglucoside preparation contains a considerable amount of free phycobilisomes, all phycobilisomes present in the digitonin preparation are physically and functionally linked to photosystem II reaction center complexes.  相似文献   

5.
A coimmobilized mixed culture of algae, Chlorella pyrenoidosa, and bacteria, Gluconobacter oxydans, has been studied. The conversion of glycerol to dihydroxyacetone(1,3-dihydroxy-2-propanone), catalysed by the bacteria, was used to indicate the oxygen supply in the immobilized preparation. The oxygen produced by the algae in the coimmobilized preparation was used by the bacteria more effectively than when the cells were immobilized separately and mixed within the reactor. A preparation consisting of only bacteria and no algae was much less effective. The coimmobilized preparation was used in the continuous production of dihydroxyacetone for six days without any significant loss of activity.  相似文献   

6.
The induction of antimicrobial activity of a new preparation, an aqueous fraction of water-oil emulsion oxidized by atmospheric oxygen, was studied. The effect of varions factors (the degree of unsaturation of the initial oil and the content of oil oxidation products in the preparation) on antimicrobial activity was determined. The antimicrobial activity of the preparation was induced by oil oxidation. The preparation produced from sardineSardinops melanostica oil (33.95% polyunsaturated fatty acids) displayed the highest antimicrobial activity. Antimicrobial activity was shown in water-soluble oil oxidation products.  相似文献   

7.
不同整地施肥措施对银杏构件生长及药用成分的影响   总被引:3,自引:1,他引:2  
研究了田间条件下不同整地施肥措施对银杏构件生长及药用成分的影响.结果表明,对银杏株高生长促进作用最大的措施依次为:施农家肥+间作>爆破整地+间作>施农家肥>爆破整地>间作,提高生长量分别为14.5%、8.6%、5.7%、3.2%和0;对银杏当年新梢生长促进作用最大的措施依次为:施农家肥+间作>爆破整地+间作>间作>施农家肥>爆破整地,提高生长量分别为58.1%、36.6%、33.1%、30.2%和14.0%;不同的整地、施肥和间作措施样地长枝数无显著差异,而短枝数量与总叶数有显著差异;施农家肥加间作措施对提高银杏药用成分含量作用最大,叶片中懈皮素和芦丁含量分别为对照的4.2倍和2.2倍.  相似文献   

8.
Chalone-containing preparation has been obtained from ascitic Ehrlich's tumour by alcohol precipitation and the effect of various preparation doses on mitotic activity and DNA synthesis in the tumour has been studied. The preparation was shown to suppress tumour cell proliferation, acting on mitosis initiation and mitotic S phase as well as on DNA synthesis in the cells at S phase of mitotic cycle. The effect of the preparation on DNA synthesis in phase S cells was more pronounced than on cells entering DNA synthesis phase. The changes in all the parameters examined were dose-dependent. The preparation effect was tissue-specific.  相似文献   

9.
1. Adenosine triphosphatase activities of dispersions prepared from bovine cerebral cortex that had been frozen, were greater than those of dispersions prepared from fresh tissue. The subcellular distribution of components of the dispersion was not altered by freezing the tissue and a microsomal fraction enriched in Na(+)+K(+)-stimulated adenosine triphosphatase activity was prepared. 2. The bovine cerebral microsomes were further treated with a 2m-sodium iodide reagent to obtain a particulate preparation with minimal Na(+)+K(+)-independent adenosine triphosphatase activity. Na(+)+K(+)-stimulated activity was increased by the sodium iodide treatment and this preparation was shown to be enriched in lipid constituents. 3. Density-gradient centrifugation of the sodium iodide treated preparation gave three main subfractions each containing approximately equal amounts of phospholipid and protein. Further exposure of the sodium iodide-treated preparation to the 2m-sodium iodide reagent altered the distribution of protein and phospholipid among the fractions obtained by density-gradient centrifugation. Dissociation of phospholipids from protein in the sodium iodide-treated preparation was brought about also by high concentrations of arginine. Concentrated solutions of arginine and sodium thiocyanate brought about dissociation of phospholipids from protein of the microsomal preparation. 4. Many amino acids were found to inhibit Na(+)+K(+)-stimulated adenosine triphosphatase activity when present in high concentrations. The inhibition was complex but resulted, in part at least, from diminished affinity for ATP and Na(+) in the presence of the amino acids. 5. A non-ionic detergent, Lubrol W, solubilized up to 40% of the enzyme activity of the sodium iodide-treated preparation together with 30% of the protein and phospholipid in the preparation. Protein was released from the sodium iodide-treated preparation by pancreatic elastase but Na(+)+K(+)-stimulated adenosine triphosphatase activity of the residue was diminished. Ultrasonic treatment of the sodium iodide-treated preparation failed to release a significant proportion of Na(+)+K(+)-stimulated adenosine triphosphatase activity into a form not deposited by ultracentrifugation.  相似文献   

10.
Purification of amylase produced by Endomyces sp. IFO 0111 was carried out. A highly purified amyloglucosidase preparation was obtained from culture broth by means of precipitation with ammonium sulfate, decolorization with rivanol, precipitation with acetone and zone electrophoresis. The homogeneity of the preparation was proved by ultracentrifugation and electrophoresis. General properties of the preparation were investigated.  相似文献   

11.
The aim of this study was to elaborate a method of heterophile mononucleosis antigen preparation useful for latex coating. This antigen was isolated from bovine red blood cells stroma by the technique of Schwarzweiss and Tomcsik with author's own modification, in which introductory extraction of erythrocytes stroma ++ was performed by means of trichloracetic acid, aqueous extraction and elution of active substance with 80% ethanol. Besides of heterophile antigen preparation obtained by the method of Schwerzweiss and Tomcsik (preparation S-T) two serologically++ active preparations were obtained (fraction I and IV), which ability to inhibit PBD agglutinating reaction and bovine red blood cells haemolysis was 16 and 8 times lower, respectively, than S-T preparation. The preparation of heterophile mononucleosis antigen obtained differed in latex coating efficacy. In order to prepare latex reagent MZ-I (from fraction I) a solution of preparation of 125 micrograms/ml concentration was used, for MZ-II (from fraction IV)--50 micrograms and for MZ-III (from preparation S-T)--15 micrograms/ml. The reagent MZ-I showed, the highest activity in agglutinating test with human serum containing heterophile mononucleosis antibodies while two others reacted with 2-4 times lover serum dilutions. Similar differentiated reactivity with these reagents was found in latex test with 15 sera from patients suspected of having infectious mononucleosis.  相似文献   

12.
A cell wall preparation of Fusobacterium necrophorum induced haemorrhagic necrosis in the skins of guinea pigs and rabbits. Effects in mice and rats were weak or absent. The toxic activity of the cell wall preparation was not reduced by heat treatment. A dermonecrotic toxin was isolated from the cell wall preparation with sodium dodecylsulphate and concentrated by precipitation with ethanol. A preparation of the bacterial cytoplasm from Fus. necrophorum induced mainly erythema.  相似文献   

13.
通过比较溶液的离子浓度对病毒形态的结构的影响,发现GCHV在低盐溶液盐低温(-20℃)保存条件下,外壳蛋白会自动降解,但不十分完全,采用含1%NP40(Nonidet-p40)的稀盐溶液处理感染病毒的细胞,经冻融及差异离心,电镜下观察到纯度较高的病毒双层衣壳,核心衣壳及散在的子粒。纯化的病毒亚单位用核酸酶消化后,与等量的福氏佐剂混合,免疫家兔制备抗体,该抗血清经台和试验测定,显示了较强的中和病毒的  相似文献   

14.
Enzymatic activity responsible for the conversion of fatty acids to alkanes catalyzed by pea leaf homogenate was found to be mainly in the microsomal fraction. This particulate preparation catalyzed alkane formation from n-C18, n-C22, and n-C24 acids at rates comparable to that observed with n-C32 acid with O2 and ascorbate as required cofactors. In each case the major alkane contained two carbon atoms less than the precursor acid. Since the preparation also catalyzed alpha-oxidation, it was suspected that some alpha-oxidation intermediate, with one less carbon atom than the substrate acid, might lose another carbon to generate the alkane. Thin-layer and radio-gas-liquid chromatographic analysis of the products generated from [U-14C]stearic acid by the particulate preparation after different periods of incubation showed that, at all time periods, alpha-hydroxy C18 acid, C17 aldehyde, and C17 acid were the major products. Since C16 alkane was the major product even after short periods of reaction, the C17 aldehyde might have been the immediate precursor of the alkane. Exogenous labeled C18 and C24 aldehyde were converted to alkanes. The alkane-synthesizing activity was solubilized from the microsomal preparation using Triton X-100. The solubilized preparation was retarded in a Sepharose 6-B column, but the hydrocarbon-forming activity was not resolved from alpha-oxidation. The solubilized preparation produced alkane with two carbon atoms less than the parent acid in a time- and protein-dependent manner. The soluble preparation also required O2 and ascorbate and, like the microsomal preparation, was inhibited by dithioerythritol and metal ion chelating agents.  相似文献   

15.
戊糖乳杆菌制剂防治仔猪腹泻效果初探   总被引:3,自引:0,他引:3  
目的进行戊糖乳杆菌活菌制剂防治仔猪腹泻的活体实验。方法以8头健康长白母猪所产的90头仔猪为实验材料,随机分组进行腹泻预防实验,设空白为对照。结果戊糖乳杆菌活菌制剂预防组的腹泻率为8.51%,对照组为78.57%,差异有非常显著性(P〈0.01)。对空白组出现腹泻的仔猪进行治疗比较实验,庆大霉素为对照。结果戊糖乳杆菌制剂治疗组的总有效率为100%,治愈率为76.47%,平均疗程5d;庆大霉素治疗组的有效率为93.75%,治愈率仅为31.25%,平均疗程6d,差异有显著性(P〈0.05)。此外,与对照比较,戊糖乳杆菌制剂预防组仔猪的精神状态好,毛色光亮,粪便成型;即使个别出现腹泻情况,连续灌服戊糖乳杆菌制剂2d(1次/d),即可痊愈。结论戊糖乳杆菌制剂可有效预防和治疗仔猪腹泻。  相似文献   

16.
Double stranded RNA was isolated from bacteriophage phi 6 parasitizing on phytobacteria. Its interferon-inducing and antiviral activities were shown in vitro and in vivo. In the culture of L-929 cells, interferon resistant to heat and acids was synthesized. The interferon could be practically completely neutralized by specific anti-interferon serum. The phage phi 6 preparation dsRNA in the lyophilized form was studied. The preparation retained its biological activity. It was shown that a preparation containing 30 per cent of dsRNA was less toxic than a preparation containing 100 per cent of dsRNA, the difference in the interferon-inducing activity being insignificant.  相似文献   

17.
In the experiment on rabbits immune response to the oral administration of a new Neisseria meningitidis whole culture preparation, serogroup A, was demonstrated. The preparation was based on the acetone fixed culture, grown by the continuous flow method under a computer-controlled constant level of oxygen. The immunological activity of the preparation was demonstrated. In the blood sera of rabbits examined by immunoenzyme assay and the passive hemagglutination test, a multiple increase in the content of hemagglutinating and IgG antibodies to polysaccharide, outer membrane proteins and lipooligosaccharide was noted, their content remaining at a high level for 303 days (the term of observation). The oral immunization with the preparation protected mice infected with N. meningitidis live culture, serogroup A.  相似文献   

18.
Phosphorylation states of the (Na+ + K+)-transporting ATPase were studied in highly purified preparations isolated from electric-eel electric organ and from lamb kidney. The steady-state level of phosphorylated lamb kidney enzyme, obtained by reaction with [gamma-32P]ATP, was not appreciably reduced in the presence of ADP unless oligomycin was present. The phosphorylated form of the electric-eel electric-organ enzyme was reduced by at least 95% under the same conditions, suggesting that the E1P state in the kidney enzyme is more transitory than that in electric organ. The level of phosphorylation from [32P]Pi was higher in the lamb kidney preparation than in the electric-organ preparation, and the difference in stimulation of phosphorylation by ouabain in the two preparations was striking. Ouabain increased the level of phosphorylation by 35% in the kidney preparation and 734% in the electric-organ preparation. The E2P state seems to be stabilized by ouabain in the latter preparation. These findings, as well as the different reactivities of the thiol groups to blocking reagents in these preparations, suggest that the tertiary structure in the enzyme isolated from these two sources is different.  相似文献   

19.
To immunize CC57BR mice a suspension of live cells of Krebs-2 ascites tumour was administered intradermally into the tail partially amputated afterwards. The growth of the tumour transplanted intraperitoneally was inhibited by 23% only after twofold immunization. Single immunization with tumour cell incubated with the cattle liver RNA preparation in conjunction with intraperitoneal administration of RNA following tumour transplantation inhibited its growth by 43--53%, while twofold administration by 84--88%. The high polymeric fraction of the preparation enhanced the immunization effect to the same measures the initial overall preparation. The treatment of the preparation with RNAase and partial depolymerization of RNA in the course of isolation resulted in the activity loss. It is concluded that the capacity of the RNA preparation for stimulating antitumour immunity is due to high polymeric fraction of RNA.  相似文献   

20.
Previous studies (Hirao and Yanagimachi: Gamete Res. 1:3–12, 1978) have found that phospholipase C (PLC) preparations inhibit sperm-egg fusion. We have attempted to duplicate these results with PLC, as well as with a more specific enzyme, phosphatidyl-inositol-specific PLC. PLC preparations were applied externally to zona-free hamster eggs prior to incubation with sperm. Phosphatidylinositol-specific PLC did not inhibit sperm penetration. The degree of sperm-egg fusion observed after egg exposure to PLC, however, was dependent upon the purity of the commercial preparation. An impure sample of PLC inhibited sperm penetration, while a more purified preparation did not. The morphology of eggs was unaffected by exposure to phosphatidylinositol-specific PLC and the more purified PLC preparation. The impure preparation, however, was disruptive primarily to the egg plasma membrane as well as to internal organelle organization. The degree of damage by the impure PLC preparation was concentration dependent. The results suggest that as purity of the PLC preparation is increased, the adverse effects of PLC on sperm-egg fusion become negligible.  相似文献   

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