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71.
Low-humidity treatment triggered an increase of the thallus area and the chlorophyll content in the following high-humidity
condition. When low-humidity treatment for 4 days was intercalated in high-humidity conditions every 16 days, the thallus
area increased 40% in 76 days. 相似文献
72.
Z. I. Bhatti K. Furukawa M. Fujita 《World journal of microbiology & biotechnology》1995,11(6):631-637
A laboratory upflow anaerobic sludge blanket reactor, seeded with fine, suspended, bacterial floc with 1.76 g volatile suspended solids/l, was used to treat synthetic methanolic waste. After 180 days of continuous peration, granular sludge with discrete granules of 1 to 2 mm diam. was formed, with 52 g volatile suspended solids/l. Granules were brown, relatively soft and had a settling velocity of 1.61 cm/s. Extracellular polymeric matter extracted from the granular sludge had high carbohydrate content but low nucleic acid content. The ash of the granular sludge contained Na+, K+ and Mg2+ up to 15.0, 11.7 and 3.75 mg/g, respectively. Scanning and transmission electron microscopy revealed that the granular sludge was dominated by methanogens resembling Methanosarcina.The authors are with the Department of Environmental Engineering, Faculty of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565, Japan 相似文献
73.
J J Holst J Fahrenkrug S Knuhtsen S L Jensen S S Poulsen O V Nielsen 《Regulatory peptides》1984,8(3):245-259
Vasoactive intestinal polypeptide (VIP) in the pig pancreas is localized to nerves, many of which travel along the pancreatic ducts. VIP stimulates pancreatic fluid and bicarbonate secretion like secretin. Electrical vagal stimulation in the pig causes an atropine-resistant profuse secretion of bicarbonate-rich pancreatic juice. In an isolated perfused preparation of the pig pancreas with intact vagal nerve supply, electrical vagal stimulation caused an atropine-resistant release of VIP, which accurately parallelled the exocrine secretion of juice and bicarbonate. Perfusion of the pancreas with a potent VIP-antiserum inhibited the effect of vagal stimulation on the exocrine secretion. It is concluded, that VIP is responsible for (at least part of) the neurally controlled fluid and bicarbonate secretion from the pig pancreas. 相似文献
74.
Summary The appearance of perinucleolar electron-dense spots in the nuclei of macroconidia ofNeurospora crassa incubated at 46C and their disaggregation after shift-down to 25 C have been investigated by high-resolution autoradiography after (5-3H) uridine pulses with or without chase periods. The RNA of these ribonucleoprotein-rich dense spots has been found to originate mainly from the heatsensitive nucleolus; after return to 25 C, the nucleolar activity was recovered and the RNA material stored either in an unprocessed or a mature rRNA form in the dense spots was found to be progressively extruded into the cytoplasm. 相似文献
75.
Summary Balance sheets were computed for total nitrogen and phosphorus in plough layer (0–15 cm) of a Typic Ustochrept soil under
continuous multiple cropping for seven years (1971–72 to 1977–78) with a fixed rotation of pearl millet (Pennisetum typhoideum L.) wheat (Triticum aestivum L.) (Vigna sinensis Savi.) The treatments considered of soil test-based rates of N, P and K, applied both singly and in combinations together with
farm yard manure, sulphur and zinc superimposed over optimum rates (100%) of NPK. Heavy, losses of N (762–899 kg ha−1) occurred in the plots which received high rates of Nviz. 150% of recommended NPK and 100% NPK plus FYM. Application of N alone accelerated N losses whereas addition of P, PK, PKS
to N minimised such losses. Enrichment of P (66 to 198 kg ha−1) occurred in all phosphate-treated plots. A marginal net decrease (29–54 kg ha−1) in P levels was observed in control and N alone treatments. 相似文献
76.
Anthers of different species of the genera Anemone, Clematis, Papaver and Nicotiana were cultured by floating on a liquid medium which overlay an agarified charcoal medium . This technique proved to be superior to conventional methods i.e. culture on either solid or liquid media. Cold treatment of Anemone anthers for 7 days after inoculation on the double layer medium gave about the same frequency of embryos per anther as corresponding cultures cold treated before inoculation. An elevation of the CO2 concentration to 2% stimulated embryogenesis in anther cultures of Anemone canadensis, Anemone vitifolia, Papaver setigerum and Papaver radicatum . Cold treatment of cultures of Anemone canadensis inhibited embryogenesis if the ensuing culture was performed in 2% CO2. On the other hand, cold treatment was stimulating, with an optimum of about 20 days, if the cultures were maintained in normal air. Chemical analysis of untreated anthers of Anemone canadensis showed the presence of abscisic acid (2.2 × 10−6 g/g anthers). Cold treatment reduced the concentration of abscisic acid to 0.6 × 10−6 g/g anthers. By use of assays with Lemna gibba as test organism, activated charcoal was shown to adsorb abscisic acid that was added to the medium. Medium treated with charcoal before inoculation of anthers of Anemone canadensis provided to inhibit embryo production. 相似文献
77.
78.
Ingrid Lombeck K. Kasperek L. E. Feinendegen H. J. Bremer 《Biological trace element research》1980,2(3):193-198
The rubidium content of whole blood was estimated by instrumental neutron activation analysis. In 46 healthy children it amounts
to {ie193-1} g/g dry weight. There was no difference between the values found for infants, toddlers, and school children.
In 29 dietetically treated patients with phenylketonuria and maple-syrup-urine disease the values were significantly lower
than in healthy children. During the first three months of diet therapy the rubidium levels remained in the lower range of
the normal values, decreasing to about 60% of the mean of normal values later on. With increasing length of diet therapy these
values tended to decrease. It remains questionable whether these decreased levels reflect only an induced biochemical phenomenon
without biological importance, or whether they are the first signs of a deficiency syndrome. 相似文献
79.
Saccharomyces cerevisiae nuclear membranes were prepared from isolated nuclei by digesting chromatin with deoxyribonuclease and ribonuclease, washing of residual nuclei with 0.5 M MgCl2, and discontinuous gradient centrifugation in buffered Ficoll solutions. Electron microscopic examination of the preparations showed single membrane and double membrane vesicles and membrane sheets. Pores or residual pores were often visible. In double membrane profiles the two unit membranes were often separated by the remains of the perinuclear cistern. The nuclear membrane fragments contained 58% protein, 23.8% phospholipid, 6% sterols, 7.1% neutral acylglycerols, 4.8% RNA, and 0.3% DNA. The phospholipid content of the membrane preparations was influenced by a phospholipase activity with acidic pH optimum. 相似文献
80.
An endogenous soluble protease has been demonstrated to unmask a Ca2+-stimulated ATPase activity in purified dog gastric microsomes. The presence of ATP during protease treatment appears essential for the manifestation of the gastric Ca2+-stimulated ATPase activity. The endogenous protease appears to have trypsin-like activity, since soybean trypsin inhibitor completely blocks the protease effect. Manifestation of the Ca2+-stimulated ATPase occurs without affecting the microsomal (H+ +K+)-ATPase activity and associated H+ uptake ability. The unmasked Ca2+-stimulated ATPase appears insensitive to calmodulin. Possible roles of the enzyme in the regulation of gastric H+ transport have been discussed. 相似文献