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1.
Sekhon  Awatar S. 《Mycopathologia》1977,60(3):145-149
Cultures of the + (UAMH 1485) and — (UAMH 1486) mating types of Nannizzia gypsea and their crosses (1485×1486) were analyzed, after 1, 2, 3, and 4 weeks growth, for fresh weight, proteins, peroxidases, esterases, acid- and alkaline-phosphatases. The + type produced slightly more growth at all periods (90, 131, 131, and 129 mg/plate) than the — mating type (90, 123, 121, and 108 mg/plate). The growth of the crosses was much less (30, 88, 83, and 94 mg/plate). Total soluble proteins per gram fresh weight was greater for the crosses (51, 33, 48, and 63 mg) than for the + (19, 32, 34, and 32 mg) and — (20, 33, 33, and 33 mg) strains. Disc-gel electrophoretic analyses revealed 6–9 protein bands in each of the mating types, and 7–8 bands (protein) in crosses, several of which showed mobility and stain uptake differences. There were 1–2 peroxidase bands in the +, -, and crosses; their patterns were generally the same in 1-week-old cultures, but slight differences were found at the subsequent harvests. The number of esterases in the +, -, and crosses was 3–4 and 2–3, respectively, but their patterns were similar. Acid- and alkaline-phosphatases of the + and -, and crosses were quite similar to one another. For all the enzymes studied, the number of bands increased after the first harvest in crosses, but in the single strains there was no constant pattern.
Zusammenfassung Kulturen von + (UAMH 1485) und — (UAMH 1486) Zuchtungstamme von N. gypsea und ihre Kreuzungen (1485×1486) waren analisiert (nach 1-, 2-, 3- und 4-Wochen-wachsen) fur frisches Gewicht, Proteinnen, Peroxidasen, Esterasen, seurige und alkalinische Phosphatasen. Die + Stamme zeigten immer etwas besseres Entwicklung (123, 131, 131, und 129 mg/Platte) Denn die – (90, 123, 121, und 80 mg/Platte).Die Kreuzungen zeigten immer viel weniger Wachstum (30, 88, 83, und 94 mg/Platte). Die total losbare Protein per gram von frischen Gewicht war immer grosser bei den kreuzungen (51, 33, 48, und 63 mg) denn fur die + (19, 32, 34, und 32 mg) und die – (20, 33, 33, und 33 mg) Stamme.Die Disk-gel Electrophoretic Analysis zeigte 6–9 Protein Bande in allen Zuchtungstammen und 7–8 Bande in den Kreuzungen, mehrere zeigten verschiedene Beweglichkeiten und die Einahme der Beize. Wir sahen 1–2 peroxidase Bande in die +, –, und in den kreuzungen; ihre Formen (Muster) waren fast immer gleich wie in der ersten Woche alte Kulturen, aber etwas verschiedenes konnte man doch sehen spater in den ernten.Die Nummer von die Esterasen in die + und – Stamme und in die kreuzungen war 3–4 und 2–3, beziehungsweise aber die die Mustern waren gleich. Die surige und lauge Phosphatasen von den +, –, und von den Kreuzungen waren ziemlich gleich.In alle Enzyme die wir untersucht haben, die Nummer von den Bandern ist immer hoher geworden nach die erste Ernte in den Kreuzungen, aber in den einzelnen Stammen es war standiges Muster.
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2.
Equipment was devised which permitted the addition of specific gaseous ions to the atmosphere of plastic chambers in which seedlings of HORDEUM VULGARIS were grown in sand culture supplied with chemically defined nutrient solutions. Moderate densities of O2 or O2 + ions (1.8×104/cm3)in air containing an added 8% of O2 accelerated the growth rate. A like number of CO2 or CO2 + ions in air containing 8% of CO2 inhibited growth, impeded the production of chlorophyll and devitalized the young seedlings. Evidence is presented that O2 and O2 + stimulate the production of cytochromes and other Fe-containing enzymes through their action on the plant regulatory system responsible for the control of Fe metabolism. The toxic effect of CO2 and CO2 + cannot be explained as yet.
Zusammenfassung Eine Apparatur wurde entwickelt, die die Zufuhr von ionisiertem Gas der AtmosphÄre in Kammern gestattet. Darin wurden Keimlinge von HORDEUM VULGARIS in Sand mit chemisch definierten NÄhrlösungen gezüchtet. Konzentrationen von 1,8×104/cm3 O2 und O2 + in Luft mit zusÄtzlich 8% O2 beschleunigten die Wachstumsrate. Die gleiche Menge CO2 und CO2 + in Luft mit zusÄtzlich 8% CO2 hemmte die Wachstumsrate, die Bildung von Chlorophyll und entkrÄftigte die Keimlinge. Es wird gezeigt,dass O2 und O2 + die Bildung von Cytochrom und anderen eisenhaltigen Enzymen anregen durcn ihre Wirkung auf das den Fe-Stoffwechsel regulierende System der Pflanze. Die toxische Wirkung von CO2 und CO2 + lÄsst sich noch nicht erklÄren.

Resume On a construit un appareil permettant d'introduire dans 1'atmosphères des ions de gaz déterminés. On a alors effectué de telles adjonctions à l'air contenu dans des cellules de plastique dans lesquelles on cultivait HORDEUM VULGARIS sur du sable et dans une solution nutritive chimiquement définie. Des densités modérées d'ions O2 ou O2 + (1,8×104/cm3) dans de l'air additionné de 8% d'O2 accélèrent la croissance. La meme concentration de CO2 et CO2 + additionnée de 8% de CO2 a ralenti la croissance et la formation de chlorophylle et a diminué la vitalite des plantes nouvellement germées. On démontre que O2 et O2 + active la formation de cytochrome et d'autres enzymes ferreuses par suite de l'action de ces ions sur le système régularisant le métabolisme du fer dans la plante. L'effet toxique du CO2 et CO2 + reste encore inexpliqué.
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3.
1. We studied the effects of selective chronic dietary sodium, chloride, or potassium depletion in young rats on vasopressin mRNA levels in the supraoptic and paraventricular nuclei, an index of vasopressin formation, and in plasma vasopressin levels, an index of vasopressin release. 2. All diets significantly increased plasma renin activity, contracted the extracellular fluid volume, and decreased serum osmolarity. 3. In the supraoptic nucleus, vasopressin mRNA levels were significantly decreased in the low-sodium group but were not significantly affected by chloride depletion. 4. There were no significant changes in vasopressin mRNA in the paraventricular nucleus after sodium or chloride dietary depletion. 5. After 2 weeks of potassium depletion, vasopressin mRNA levels were decreased in the supraoptic nucleus. When potassium depletion was prolonged for 3 weeks, vasopressin mRNA levels increased in both supraoptic and paraventricular nuclei. 6. Plasma vasopressin levels were high in animals subjected to dietary chloride depletion or to 3 weeks of potassium depletion. Dietary sodium depletion or 2 weeks of dietary potassium depletion did not significantly affect plasma vasopressin. 7. Our results show that chronic sodium, chloride, or potassium depletion differentially affect brain vasopressin mRNA and vasopressin release in young rats. 8. The effect of these diets may be mediated through changes in the extracellular fluid volume, serum osmolarity, and/or renin angiotensin system.  相似文献   

4.
Chi Lin  Chuan  Huei Kao  Ching 《Plant and Soil》2001,237(1):165-171
The relative importance of endogenous abscisic acid (ABA), as well as Na+ and Cl in NaCl-induced responses related to growth in roots of rice seedlings were investigated. The increase in ammonium, proline and H2O2 levels, and cell wall peroxidase (POD) activity has been shown to be related to NaCl-inhibited root growth of rice seedlings. Increasing concentrations of NaCl from 50 to 150 mM progressively decreased root growth and increased both Na+ and Cl. Treatment with NaCl in the presence of 4,4-diisothiocyano-2,2-disulfonic acid (DIDS, a nonpermeating amino-reactive disulfonic acid known to inhibit the uptake of Cl) had less Cl level in roots than that in the absence of DIDS, but did not affect the levels of Na+, and responses related to growth in roots. Treatment with 50 mM Na-gluconate (the anion of which is not permeable to membrane) had similar Na+ level in roots as that with 100 mM NaCl. It was found that treatment with 50 mM Na-gluconate effected growth reduction and growth-related responses in roots in the same way as 100 mM NaCl. All these results suggest that Cl is not required for NaCl-induced responses in root of rice seedlings. Endogenous ABA level showed no increase in roots of rice seedlings exposed to 150 mM NaCl. It is unlikely that ABA is associated with NaCl-inhibited root growth of rice seedlings.  相似文献   

5.
Plants of Datura stramonium var. tatula L. Torr. were cultivated on vermiculite and received two different mineral solutions. In one treatment only NO3 -nitrogen was added, while in the other NO3 -nitrogen was partly (20%) replaced by NH4 +-nitrogen. Total dose of nitrogen as well as interionic ratios were kept constant in both treatments. With the combined treatment (NO3 -NH4 +) a significant higher hyoscyamine content was found at the time when highest biomass was reached. This was apparently the result of an increased alkaloid biosynthesis. Also scopolamine content was positively influenced, but only at a point past maximal biomass yield.No significant differences in amounts of nitrogen bound per plant were found between both treatments.The higher alkaloid content observed with the combined treatment was associated with a higher relative proportion of bound nitrogen present in the alkaloids. It seems that more nitrogen is available for secondary metabolism when NH4 +-nitrogen is present in the culture medium.  相似文献   

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7.
Transport of 86Rb+/K+, 22Na+, 36Cl?, and [3H]indole acetic acid (IAA) has been studied on suspension-cultured cells of the parsley, Petroselinum crispum (Mill) Nym. By compartmental analysis two intracellular compartments of K+, Na+, and Cl? have been identified and ascribed to the cytoplasm and vacuole; half-times of exchange were around 200 s and 5 h, respectively. According to the Ussing-Teorell flux equation, active transport is required for the influx into the cytoplasm at the plasmalemma (K+, Cl?) and the tonoplast (K+, Na+, Cl?). The plasmalemma permeability pattern, PK:PNa:PCl=1.00:0.24:0.38, features an increased chloride permeability compared with cells from higher plant tissues. IAA uptake showed an exponential timecourse, was half-maximal after 10 min, and a linear function of the IAA concentration from 10?9 to 10?5 M. IAA and 2,4-dichlorophenoxy acetic acid reduce the apparent influx of K+, Na+, Cl? during the initial 30 min after addition and subsequently accelerate both in- and efflux of these ions. We discuss that auxins could affect the ion fluxes in a complex way, e.g. by protonophorous activity and by control of the hypothetical proton pump.  相似文献   

8.
Z. Ping  I. Yabe  S. Muto 《Protoplasma》1992,171(1-2):7-18
Summary K+, Cl, and Ca2+ channels in the vacuolar membrane of tobacco cell suspension cultures have been investigated using the patch-clamp technique. In symmetrical 100mM K+, K+ channels opened at positive vacuolar membrane potentials (cytoplasmic side as reference) had different conductances of 57 pS and 24 pS. K+ channel opened at negative vacuolar membrane potentials had a conductance of 43 pS. The K+ channels showed a significant discrimination against Na+ and Cl. The Cl channel opened at positive vacuolar membrane potentials for cytoplasmic Cl influx had a high conductance of 110pS in symmetrical 100mM Cl. When K+ and Cl channels were excluded from opening, no traces were found of Ca2+ channel activity for vacuolar Ca2+ release induced by inositol 1,4,5-trisphosphate or other events. However, we found a 19pS Ca2+ channel which allowed influx of cytoplasmic Ca2+ into the vacuole when the Ca2+ concentration on the cytoplasmic side was high. When Ca2+ was substituted by Ba2+, the conductance of the 19 pS channel became 30 pS and the channel showed a selectivity sequence of Ba2+Sr2+Ca2+Mg2+=10.60.60.21. The reversal potentials of the channel shifted with the change in Ca2+ concentration on the vacuolar side. The channel could be efficiently blocked from the cytoplasmic side by Cd2+, but was insensitive to La3+, Gd3+, Ni2+, verapamil, and nifedipine. The related ion channels in freshly isolated vacuoles from red beet root cells were also recorded. The coexistence of the K+, Cl, and Ca2+ channels in the vacuolar membrane of tobacco cells might imply a precise classification and cooperation of the channels in the physiological process of plant cells.  相似文献   

9.
We evaluated (1) the longitudinal pattern of stream chemistry and (2) the effects of the riparian zone on this longitudinal pattern for nitrate (NO3 ), dissolved organic carbon (DOC), and total dissolved iron (Fe). We selected two small watersheds; the “southern watershed” had an extending riparian wetland and the “northern watershed” had a narrow riparian area. Stream NO3 concentrations decreased from the spring to outlet of both watersheds. In the southern watershed, stream DOC concentration decreased from the spring to midstream and then increased to the outlet. Stream Fe concentration in the southern watershed longitudinally increased. On the other hand, the northern watershed exhibited no longitudinal pattern for DOC and Fe concentrations. In both watersheds, while NO3 concentrations in the soil and ground water were lower than those in the stream waters, DOC and Fe concentrations exhibited the opposite patterns. The longitudinal decreases of NO3 concentrations in both streams and increase of stream Fe in the southern watershed mainly resulted from the inflow of the soil and ground water to the stream. The decrease in stream DOC from the spring to midstream in the southern watershed was due to the deep groundwater having low DOC, while the subsequent increase to the surrounding soil and ground water. Moreover, considerations of stream solute flow with soil and ground water chemistry suggested other mechanisms adding NO3 and removing/diluting DOC and Fe, especially for the northern watershed; coexistence of oxidizing and reducing conditions in the riparian zone might control the longitudinal concentration change in the stream water chemistry.  相似文献   

10.
The ionic fluxes associated with the ATP-dependent acidification of endocytic vesicles were studied in a preparation isolated from rabbit reticulocytes enriched for transferrin-transferrin receptor complexes. No vesicle acidification was observed in the absence of intra- and extravesicular ions (sucrosein/sucroseout), while maximal acidification was observed with NaClin/KClout·K in + was a poor substitute for Na in + , and Cl out could be replaced by other anions with the following efficacy of acidification: Cl>Br>I>PO 4 3– >gluconate>SO 4 2– . Flux studies using36Cl and22Na+ showed that the vesicles had a permeability for Cl and Na+, and that ATP-dependent H+ pumping was accompanied by a net influx of Cl and a net efflux of Na+ provided that there was a Na+ concentration gradient. After 3 mins, the time necessary to maximal acidification, the electrical charge generated by the entrance of H+ was countered to about 45% by the Cl influx and to about 42% by the Na+ efflux. These studies demonstrated that both Cl and Na+ fluxes are necessary for optimal endocytic vesicle acidification.  相似文献   

11.
A thermosensitive uracil requiring mutant of Bacillus subtilis Marburg 168 thy trp2 ts42 was examined as to the colony forming ability at the permissive and nonpermissive temperatures. The viability of the mutant cells decreased rapidly at the restrictive temperature in the modified Woese’s (MW) medium. However, the cells retained viability when sodium succinate or potassium chloride was added to the medium at that temperature although uracil deficiency was unchanged. A little but significant incorporation of adenine-8-14C into RNA still continued even after the incorporation of N-acetyl-3H-d-glucosamine into acid insoluble fraction of the cells terminated in the MW medium at 48°C. Both incorporations as well as increase of absorbance were slowed down in the presence of sodium succinate at 48°C. This mutant, ts42, was more sensitive to deoxycholate (DOC) than the parent strain. The restoration of colony forming ability after the temperature shift back from 48 to 37°C was suppressed by the addition of DOC to the medium. However, the cell became resistant to DOC when uracil was added to the medium prior to the temperature shift.  相似文献   

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13.
Li  Junhua  Yu  Haitao  Yang  Yanjun  Drummond  Calum J.  Conn  Charlotte E. 《Food biophysics》2021,16(1):48-57

Oleogels based on three different oils (sunflower oil, solid coconut oil and liquid coconut oil) were formulated using β-sitosterol. In general, an observed increase in crystallinity was correlated with an increase in the gel storage modulus and hardness. Addition of lecithin promoted the formation of needle-like crystals of β-sitosterol with a corresponding increase in strain tolerance and oil-trapping capacity for oleogels produced with liquid oils. However, the incorporation of β-sitosterol crystals with or without lecithin into oleogels containing solid coconut oil reduced its strain tolerance by interrupting the formation of continual radiolitic crystal structures. The use of sunflower oil (long chain fatty acids) was more favourable to the packing and growth of gelator crystals and the formation of an elastic gel, in comparison to liquid coconut oil (short chain fatty acids). Overall, the type and physical state of oil influence the formation of oil crystal network, thus affecting its gel properties. These findings allow the better understanding of β-sitosterol-based oleogels, providing opportunity to design for the application as a fat-replacer and lowering solid fat content.

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14.
Summary The distribution of Corynebacterium parvum labeled with 131iodine or 99mtechnetium was studied in 17 patients with bronchogenic carcinoma. The labeled bacteria were given intravenously or intrapleurally and monitored by whole-body gamma tracking and samples of blood and urine. Even though the rate of physical decay is quite different for 131iodine and 99mtechnetium, the tracking time of labeled bacteria was limited to 24 h after injection for both radioactive isotopes. Technetium labeling was preferred because of greater imaging resolution and less radiation dose to the patient. Following intravenous administration, labeled C. parvum was found predominantly in the liver and spleen, and in a lesser amount in the lung. Radioactivity was confined to the pleural cavity after intrapleural injection. These results suggest the combined intravenous and intrapleural route of adjuvant immunosupportive agents such as C. parvum for operable lung cancer patients.  相似文献   

15.
The two spotted spider mite, Tetranychus urticae Koch, is an important herbivore pest of apple trees in Northwest China. This spider mite and another less damaging spider mite, Eotetranychus pruni Oudemans, are attacked by a common and often effective phytoseiid predator, Euseius finlandicus (Oudemans). Functional relationships were studied in the field to evaluate the impact of E. pruni and E. finlandicus on T. urticae. The results from this study showed that the predator-mediated apparent competition strongly affected the population dynamics of T. urticae. The addition of the apparent competitor E. pruni alone had little impact on T. urticae densities. Although the release of the predator E. finlandicus alone could result in reduction in T. urticae densities, the greatest reduction in T. urticae densities occurred in plots where both the predator E. finlandicus and apparent competitor E. pruni were released. In apple orchards, the early introduction of both the apparent competitor E. pruni and predator E. finlandicus would evidently increase the population size of the predator E. finlandicus and consequently significantly enhance the control of T. urticae populations. It is concluded from the study that the predator and apparent competitor release might be an appropriate control for the target species.  相似文献   

16.
The milk protein β-lactoglobulin (βLG) dominates the properties of whey aggregates in food products. Here we use spectroscopic and calorimetric techniques to elucidate how anionic, cationic and non-ionic surfactants interact with bovine βLG and modulate its heat-induced aggregation. Alkyl trimethyl ammonium chlorides (xTAC) strongly promote aggregation, while sodium alkyl sulfates (SxS) and alkyl maltopyranosides (xM) reduce aggregation. Sodium dodecyl sulfate (SDS) binds to non-aggregated βLG in several steps, but reduction of aggregation was associated with the first binding step, which occurs far below the critical micelle concentration. In contrast, micellar concentrations of xMs are required to reduce aggregation. The ranking order for reduction of aggregation (normalized to their tendency to self-associate) was C10-C12>C8>C14 for SxS and C8>C10>C12>C14>C16 for xM. xTAC promote aggregation in the same ranking order as xM reduce it. We conclude that SxS reduce aggregation by stabilizing the protein's ligand-bound state (the melting temperature t(m) increases by up to 10°C) and altering its charge potential. xM monomers also stabilize the protein's ligand-bound state (increasing t(m) up to 6°C) but in the absence of charged head groups this is not sufficient by itself to prevent aggregation. Although micelles of both anionic and non-ionic surfactants destabilize βLG, they also solubilize unfolded protein monomers, leaving them unavailable for protein-protein association and thus inhibiting aggregation. Cationic surfactants promote aggregation by a combination of destabilization and charge neutralization. The food compatible surfactant sodium dodecanoate also inhibited aggregation well below the cmc, suggesting that surfactants may be a practical way to modulate whey protein properties.  相似文献   

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1 IntroductionInthenaturemanyanimals ,suchas geckoes ,flies ,bees ,locustsandspiders ,haveamagicabilitytomoveorholdonvarioussurfaces roughorsmoothfloors ,wallsorceilings.Themechanism ,howtheani malsattachto ,holdonanddetachfromthesurfaces ,mayenlightenusonwall climbingrobotsformthefeetdesign .Therobotsaregreatlyindemandinvacuumcircumstance ,insurvivorsearchinginflown downbuildingandinpipelineinspectingandrepairing .Themechanismsmayalsoshowushowtodesignhighadap tivemanipulators.Thebionicfeetd…  相似文献   

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