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Using Toyopearl and cyclohexane: cyclohexanol solvent, fourCl-containing Chls were separated from 36Cl-labeled cells ofthe blue-green, Plectonema boryanum. In normally grown cells,all four Cl-containing chlorophylls amounted to less than 1/2,000of the total Chi and about 1/50 of P700, values much lower thanpreviously reportedcontents of Chi RC I, and varied from algato alga. The level of Cl-containing Chi was markedly enhancedwhen the cells were poisoned with methyl viologen. These resultssuggests that these Cl-containing Chls are not related to thereaction center of PS I. (Received June 23, 1987; Accepted September 17, 1987)  相似文献   
3.
After the addition of actin to serum, the binding of actin to serum actin-binding proteins was analyzed by the method of immunoblotting using monospecific antibodies against vitamin D-binding protein (DBP) (group-specific component, Gc), human skeletal actin and human plasma gelsolin. When increasing amounts of globular actin were added to serum, actin bound to DBP preferentially. After exhausting DBP, actin began to bind to plasma gelsolin. When equally increasing amounts of filamentous actin were added to serum, actin was bound to both plasma gelsolin and DBP, and then uncomplexed DBP removed one actin molecule from gelsolin-actin 1:2 complex, resulting in a gelsolin-actin 1:1 complex. These results support the theory that the actin-depolymerizing activity of serum is due to the concerted role of plasma gelsolin and DBP.  相似文献   
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A sensitive method for detecting metallothioneins (MTs) by use of silver staining after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of carboxymethylated MTs was developed. Carboxymethylation of metallothioneins is indispensable because it prevents their aggregation, thereby allowing each of them to be detected as a single band by SDS-PAGE. However, when the gel was subjected to the silver-staining method of C. R. Merril, D. Goldman, S. A. Sedman, and M. H. Ebert [(1981) Science 211, 1437-1438], the image of carboxymethylated purified MTs was totally negative. Pretreatment of the gel with 1% sodium thiosulfate just prior to the silver-staining procedure successfully reversed the negative image of carboxymethylated MTs. Further, they could be detected with a limit of nanogram levels per lane. This method can be applied to MTs in cell extracts from cultured cell lines treated with cadmium or to those from liver of cadmium-intoxicated mice.  相似文献   
6.
T Yamada  K Ohsawa  H Ohno 《Jikken dobutsu》1988,37(3):325-331
The alkaline solution method for detecting uterine implantation sites (metrial glands or spots after delivery), which indicate the position of the embryo, was compared with conventional methods using Turnbull blue (Salewski's technique) and benzyl benzoate (Orsini's technique) in rats. When rat uteri were immersed directly in 2% sodium hydroxide [NaOH], potassium hydroxide [KOH] solution or one of several other alkaline solutions for one hour, the uteri were cleared. Then the metrial glands could be observed without further staining, and the spots after delivery with further staining. After alkaline treatment, unstained metrial glands appeared as yellowish-white degenerated masses and stained spots after delivery appeared as yellowish-brown patches covered with yellowish-white lumps. These yellowish-brown or yellowish-white sites were probably stained by the iron in hemosiderin deposits in the placental scar or in a vestige of the metrial glands left over from pregnancy. Formalin-fixed uteri were not cleared by immersion in a high concentration of NaOH, KOH or other alkaline solutions, but the spots after delivery were stained by this treatment. Turnbull blue did not stain the metrial glands, which contain no iron. Benzyl benzoate cleared fixed or unfixed uteri and allowed observation of the metrial glands and spots after delivery although the entire process required a few days and the specimens became hard and shriveled. The best and most convenient solution for clearing the rat uterus and for staining implantation sites was 2% NaOH or KOH.  相似文献   
7.
Considerable inherent variations in the relation between macropterous and brachypterous wing forms, and nymphal density were found in field populations of the brown planthopper, Nilaparvata lugens Stål (Homoptera: Delphacidae), collected from various locations in Japan. When compared under uniform laboratory rearing conditions, most of the female populations exhibited higher ratios of macropters with increasing nymphal density, but some showed extremely high proportion of brachypters and the others were highly macropterous, over broad ranges of density. These results indicate the possibility that the planthoppers in Japan, which are known not to persist in winter, are derived from different migration sources.About ten generations of successive selection for brachyptery from a population showing usual density-dependent wing morphism generated populations similar to highly brachypterous ones mentioned above. Genetic analysis of the inheritance of wing morphism revealed that brachyptery in the females was controlled by a single pair of dominant alleles. However, in the males wing forms did not segregate so clearly in the crossing experiments. This suggests that wing morphism in N. lugens in under sex-limited inheritance.
Einwanderung von Nilaparvata lugens mit unterscheidlicher Reaktion auf Populationsdischte bei der Flügelausbildung
Zusammenfassung In Feldpopulationen von Nilaparvata lugens Stål., welche in verschiedenen Regionen Japans gesammelt wurden, bestand in der Beziehung zwischen makropteren bzw. brachypteren Flügelformen und der Larvendichte eine beträchtliche Variation. Unter einheitlichen Zuchtbedingungen im Laboratorium stieg der Makropterenanteil bei den meisten Weibchenpopulationen mit steigender Temperatur; bei einigen Populationen hingegen war entweder der Brachypterenanteil oder der Makropterenanteil extrem hoch und zwar über weite Dichtebereiche. Dies deutet auf die Möglichkeit hin, dass die Zikade in Japan, wo sie bekanntlich nicht überwintert, jeweils aus verschiedenen Quellen einwandert.Wenn eine Population mit der üblichen dichteabhängigen Flügelausbildung 10 Generationen lang auf Brachypterie selektioniert wurde, entstanden Populationen, die den erwähnten hochbrachypteren Populationen aus dem Feld glichen. Die genetische Analyse der Vererbung der Brachypterie ergab, dass bei Weibchen ein einzelnes dominantes Allel verantwortlich ist. Bei Männchen dagegen trennten sich bei Kreuzungsexperimenten die Flügelformen nicht so klar. Dies deuted auf Unterschiede zwischen den Geschlechtern bei der Vererbung der Flügelformen.
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8.
Summary The translation activity of mRNA coding for argininosuccinate synthetase in total RNA extracted from the liver of three patients with quantitative-type citrullinemia was determined using a cell-free translation system. In two patients, the hepatic content of the enzyme was about 20% of the control value, whereas translatable mRNA level for the enzyme was similar to or slightly lower than those of control livers. In the third patient, the enzyme content was about 50% of the control value, and mRNA activity for the enzyme was low normal. These results indicate that at least in the first two patients, the decrease in the enzyme protein is due either to increased degradation of the enzyme or to decreased translation in the patient's liver.  相似文献   
9.
T Ochi  M Mogi  M Watanabe  M Ohsawa 《Mutation research》1984,137(2-3):103-109
Inducibility of chromosomal aberrations and cytotoxicity in cultured Chinese hamster cells by cadmium chloride (CdCl2) was investigated under 3 different treatment conditions: (i) 2-h treatment in MEM medium supplemented with 10% fetal bovine serum (MEM + 10% FBS) or (ii) in HEPES-buffered Hanks' solution (HEPES-Hanks), and (iii) continuous treatment for 24 h in MEM + 10% FBS. Two-h treatment with CdCl2 in HEPES-Hanks or continuous treatment for 24 h in MEM + 10% FBS was respectively 2 or 3 times more cytotoxic than 2-h treatment with the metal in MEM + 10% FBS. Continuous treatment for 24 h with a CdCl2 concentration in excess of 5 X 10(-6) M was too toxic to the cells to allow chromosomal analysis, and moreover, only a slight increase in incidence of chromosomal aberrations was observed at a concentration of 5 X 10(-6) M CdCl2. In contrast, a marked and concentration-dependent increase in incidence of chromosomal aberrations was observed after post-treatment culture for 22 h follows 2-h treatment with 1 X 10(-6) M to 5 X 10(-5) M of CdCl2 in both MEM + 10% FBS and HEPES-Hanks. Two-h treatment with cadmium in HEPES-Hanks was approximately 3 times more potent for the induction of chromosomal aberrations than that in MEM + 10% FBS. Types of aberrations induced by CdCl2 mainly consisted of chromatid gaps and breaks, although a few exchanges, dicentrics and fragmentations were observed at high concentrations of cadmium. Increase in incidence of tetraploidy was also observed with a concentration dependency after 2-h treatment with CdCl2. Potency of CdCl2 to induce chromosomal aberrations after 2-h exposure was comparable to that of benzo[a]pyrene activated with S9 at equitoxic concentrations. Two-h treatment with cadmium markedly inhibited incorporation of [3H]thymidine, even at concentrations at which incorporation of [3H]uridine or [3H]leucine was less inhibited. However, the inhibition of [3H]thymidine incorporation by cadmium was reversible and the incorporation restored to the control level during 2-6 h of post-treatment incubation. These findings suggest that restoration of DNA synthesis after cadmium exposure is required for the efficient detection of chromosomal aberrations induced by the metal.  相似文献   
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