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J. L. Hall 《Planta》1969,89(3):254-265
Summary The distribution of ATP-ase and other nucleotide phosphatases has been studied in young root tips of maize, barley and broad bean using frozen and paraffin sections stained by standard lead sulphide precipitation procedures. High ATP-ase activity was found at the root and cell surface which is in agreement with previous biochemical studies using excised roots and cell wall preparations. Staining was also found in the nuclei and at particulate sites in the cytoplasm. Differences were observed between the present work and the staining pattern obtained for -glycerophosphatase, and between ATP-ase staining in the three roots studied. These results are discussed in relation to the possible physiological activity of the enzymes and to the differences found between earlier histochemical studies of ATP-ase activity.Abbreviations F.L. frozen longitudinal - F.T. frozen transverse  相似文献   
994.
Summary Different staining procedures, various digestion methods and autoradiographic techniques were employed to study the structure and composition of the nucleolus and of the nucleolonema, after unmasking the latter by adenosine treatment. The presence of DNA, RNA, protein and lipid in these structures has been shown. It has been demonstrated that the filamentous structure within the nucleolus — the nucleolonema— has a core of DNA, around which RNA and protein have accumulated. The structure of the nucleolonema suggests that it is in a highly active state, in synthesizing ribosomal RNA and protein.We take the opportunity to express our gratefulness to the Director, Prof. Dr. Hans Lettré, for providing facilities to work in this Institute. We like to thank our other colleagues, particularly Dr. N. Paweletz, for their valuable help during the course of the investigations.  相似文献   
995.
Assessment was made of 5% local guanethidine in treating eye manifestations in euthyroid patients with either treated thyrotoxicosis or ophthalmic Graves''s disease. In a double-blind crossover study guanethidine caused greater improvement in lid retraction than a control solution. A long-term study showed that this improvement was maintained. A much lower incidence of side-effects was noted with 5% guanethidine than with 10% solution.  相似文献   
996.
To investigate the effect of different environmental and personal factors on ventilatory function 10,971 children resident and going to school in four areas of Kent were examined. Details of past respiratory illnesses were obtained by a questionary completed by the parents; the examination included measurement of height, weight, and peak expiratory flow.Area of residence, social class, family size, and a past history of pneumonia, bronchitis, or asthma were found to be associated with differing levels of peak expiratory flow. These four factors acted independently, and the effects were additive. It is suggested that environment in the early years of life can produce adverse changes which may exist throughout life and contribute to the development of chronic respiratory disease.  相似文献   
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Morphological, cultural, biochemical, and serological characteristics of 79 strains of Vibrio parahemolyticus isolated from patients suffering from gastroenteric disease in Japan were compared with 17 suspected V. parahemolyticus cultures isolated from wound infections and 14 nonpathogenic vibrios isolated from an estuarine environment in the United States. These groups were differentiated on the basis of several key reactions which included: the range of growth temperature and salt tolerance; the production of catalase and acetoin; the hydrolysis of starch; the fermentation and utilization as single carbon source of sucrose, cellobiose, and arabinose; and the ability to swarm on 1% agar. The separation of the groups on the basis of cultural and biochemical analyses was confirmed by means of slide agglutinations with specific anti-K antisera. The results of this study strongly suggest that the wound infection isolates are V. parahemolyticus species which are easily distinguished from the nonpathogenic estuarine vibrios.  相似文献   
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