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81.
Fractional analysis of phosphorus compounds in plant tissue has been carried out by many workers, and reported on tobacco plant by Holden (1) and Komatsu (2). The fractional distribution of foliar absorbed phosphorus was investigated by Yatazawa (3) who indicated that the phosphorus was first converted into the phosphate-ester as an intermediate substance on the phosphorus metabolism. The methods of fractional analysis used by these authors were based on the method proposed by Page and Umbereit (4) in which they used trichloroacetic acid as the first extracting reagent. Recently, in order to separate the protein bound phosphorus, Wildmann, Campell and Bonner (5) adopted the salting-out method without using trichloroacetic acid. They reported that the protein-bound phosphorus plays an important role and is in the dynamic state. Fujiwara and Kadowaki (6) paid attention to the phosphorus bound to cytoplasmic protein as energy-rich phosphate compounds, and adopted the method so as to separate such compounds. In order to reveal the utilization of foliar absorbed phosphorus by the tobacco plant, the fractional distribution of phosphorus was examined. In this paper, the degree of change to organic phosphorus was taken as an index of phosphorus utilization. Paper electrophoresis was used for this purpose because the inorganic and the protein-bound phosphorus could be separated easily.  相似文献   
82.
Der größere Teil des Stickstoffhaltiges Düngesmittels sind anorganische Substanzen, und nur das Harnstoff und Kalkstickstoff können organische genannt werden, aber seine Geschwindigkeiten der Zersetzung im Boden sind ziemlich schnell, also sie haben keine dauernde Wirkung, sondern haben schnell Düngewirkung.  相似文献   
83.
Im ersten Bericht (1) wir beschrieben eine Weise die rein Monomethlolharnstoff im große Ausbeute darstellt, aber es ist unklar, ob dem Düngemittel oder einem Bestandteil des komplex Düngemittel, Monomethylolharnstoff angemesst ist oder nicht. Also, wir untersuchten einige Eigenschaften wie folgt.  相似文献   
84.
ABSTRACT:   To determine characteristics which may reflect the behavioral quality of red tilefish Branchiostegus japonicus after release, five wild and four hatchery-reared fish were observed in a laboratory and in the sea. The diel activity of the fish was recorded on video tape for 2 days in a tank, where the light condition was regulated to vary periodically over 24 h. The individuals were then released in Maizuru Bay and tracked using acoustic telemetry. Four wild individuals became most active at dawn during a day in the tank, and settled near the release area to stay for 28–104 days after release in Maizuru Bay. In contrast, one wild and four hatchery-reared individuals were not active at dawn, and then did not settle in Maizuru Bay after release. Among the four settled wild individuals, the more active a fish had been in the tank, the more distant the individual moved from the release point until its settlement. The diel activity pattern should be a factor deciding whether red tilefish would settle nearby after release, and the relative amount of activity during rearing is probably related to the degree of dispersion within the release area.  相似文献   
85.
ABSTRACT:   Anesthetized body length ( La ), an accurate measurement of body size of Japanese sea cucumber Apostichopus japonicus , is measured by using l -menthol anesthetizer but it is difficult to apply La in the field. An estimation method of La from only one simultaneous measurement of body length ( L ) and body breadth ( B ), regardless of the degree of contraction or extension of the body, is proposed. In simultaneous measurement of L and B for each of 150 animals of both the green and the black types of A. japonicus , there were significant negative correlations between L and B in all animals. Further, √( L  ×  B ) was approximately constant regardless of the animals' body form (coefficient of variance: 0.01–0.06). Thus, the regression equations for Le , estimated La , were calculated: the green type, Le  = 2.32 + 2.02 × √( L · B ); and the black type, Le  = 1.34 + 2.12 × √( L · B ). The error values between Le from these equations and La were small. The variances of Le were approximately one-quarter of those of L and half of B . From these, the equations can be used for body size measurements taken in the field.  相似文献   
86.
We have performed an in situ test of the iron limitation hypothesis in the subarctic North Pacific Ocean. A single enrichment of dissolved iron caused a large increase in phytoplankton standing stock and decreases in macronutrients and dissolved carbon dioxide. The dominant phytoplankton species shifted after the iron addition from pennate diatoms to a centric diatom, Chaetoceros debilis, that showed a very high growth rate, 2.6 doublings per day. We conclude that the bioavailability of iron regulates the magnitude of the phytoplankton biomass and the key phytoplankton species that determine the biogeochemical sensitivity to iron supply of high-nitrate, low-chlorophyll waters.  相似文献   
87.
Chlamydophila felis is a causative agent of acute and chronic conjunctivitis and pneumonia in cats. Cats can be vaccinated with killed or attenuated C. felis. However, current serodiagnostics cannot distinguish these cats from naturally infected cats. This causes difficulty of early diagnosis and seroepidemiological survey for C. felis. We previously reported that C. felis CF0218 can be used as a C. felis-infection-specific diagnostic antigen in experimentally infected and/or vaccinated cats. In this study, we evaluated an enzyme-linked immunosorbent assay using recombinant CF0218 as antigen (CF0218-ELISA) to detect anti-C. felis antibody in 714 sera of domestic cats whose histories of vaccination against C. felis are known. The 44 vaccinated cats were 93% negative using CF0218-ELISA; half of these scored positive by immunofluorescence assay (IFA) using C. felis-infected cells as antigen. The 670 non-vaccinated cats had CF0218-ELISA positivity rates that were statistically in agreement with IFA (18% vs. 21%). These results show that CF0218, which was identified as a C. felis-infection-specific antigen, is a useful serodiagnostic antigen to distinguish naturally C. felis-infected cats from vaccinated and non-infected cats.  相似文献   
88.
Two new water-soluble phenanthroperylene quinones, gymnochrome H (2) and monosulfated gymnochrome A (3), as well as the known compounds gymnochrome A (4) and monosulfated gymnochrome D (5) were isolated from the deep-sea crinoid Hypalocrinus naresianus, which had been collected in the deep sea of Japan. The structures of the compounds were elucidated by spectroscopic analysis including HRMS, 1D 1H and 13C NMR, and 2D NMR. The absolute configuration was determined by ECD spectroscopy, analysis of J-couplings and ROE contacts, and DFT calculations. The configuration of the axial chirality of all isolated phenanthroperylene quinones (2–5) was determined to be (P). For gymnochrome H (2) and monosulfated gymnochrome A (3), a (2′S,2″R) configuration was determined, whereas for monosulfated gymnochrome D (5) a (2′R,2″R), configuration was determined. Acetylated quinones are unusual among natural products from an echinoderm and gymnochrome H (2) together with the recently reported gymnochrome G (1) represent the first isolated acetylated phenanthroperylene quinones.  相似文献   
89.
OBJECTIVE: To describe spirochaetal infections in the feet and colon of cattle affected with papillomatous digital dermatitis (PDD) and colitis respectively. PROCEDURE: Eighty-two slaughtered animals were macroscopically examined for the presence of PDD. Tissues of two cattle affected with PDD were examined by histology, immunohistochemistry, electron microscopy and bacteriology for spirochaetal infection. RESULTS: Two adult cattle (a 2-year-old beef bullock and 7-year-old Holstein dairy cow) were affected with PDD. Histologically, numerous argyrophilic and gram-negative filamentous or spiral spirochaetes were found deep in the PDD lesions. Epithelial and goblet cell hyperplasia and oedema of the lamina propria mucosa with macrophage and lymphocyte infiltration were observed in the caecum and colon in the cattle. Numerous spirochaetes were present in the crypts and some had invaded epithelial and goblet cells, and caused their degeneration. Immunohistochemically the organisms stained positively with polyclonal antisera against Treponema pallidum and Brachyspira (Serpulina) hyodysenteriae. Ultrastructurally, the intestinal spirochaetes were similar to the spirochaetes in PDD. They were 6 to 14 pm long, 0.2 to 0.3 pm wide and had 4 to 6 coils and 9 axial filaments per cell. Campylobacter species were isolated from the PDD and intestinal lesions, but spirochaetes were not. CONCLUSION: Concurrent infections with morphologically similar spirochaetal organisms may occur in the feet and colon of cattle in Japan.  相似文献   
90.
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