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61.
A rapid bacterial identification method by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) using ribosomal proteins coded in S10 and spc operons as biomarkers, named the S10-GERMS (the S10-spc-alpha operon gene encoded ribosomal protein mass spectrum) method, was applied for the genus Bacillus a Gram-positive bacterium. The S10-GERMS method could successfully distinguish the difference between B. subtilis subsp. subtilis NBRC 13719(T) and B. subtilis subsp. spizizenii NBRC 101239(T) because of the mass difference of 2 ribosomal subunit proteins, despite the difference of only 2 bases in the 16S rRNA gene between them. The 8 selected reliable and reproducible ribosomal subunit proteins without disturbance of S/N level on MALDI-TOF MS analysis, S10, S14, S19, L18, L22, L24, L29, and L30, coded in S10 and spc operons were significantly useful biomarkers for rapid bacterial classification at species and strain levels by the S10-GERMS method of genus Bacillus strains without purification of ribosomal proteins.  相似文献   
62.
The interlayered hydroxy-aluminum of a chlorite-smectite intergrade in a dark-red soil derived from a pyroxene andesite altered by hydrothermal action was extracted easily by boiling treatments using both sodium-citrate and ammonium-fluoride solutions. Moreover, this interlayered aluminum was released partially by using a dithionite-citrate-bicarbonate system and an acid ammonium-oxalate solution which were prepared originally for removing the coexistent sesquioxides from soils.  相似文献   
63.
The objective of the present study was to identify the limiting factors in biomass productivity of new tropical rice lines (panicle weight type) by analyzing the relationship between root and shoot activity. Five field experiments using three new lines, IR65598-112-2, IR65600-42-5-2, and IR68544-29-2-1-3-1-2, and one of the highest-yielding indica rice varieties (panicle number type), IR72, were conducted at the International Rice Research Institute from 1997 to 2002. Specific absorption rate of N (SARN , mg N g-1 root dry weight d-1), specific stem sap exudation rate (sap exudation rate, g exudate g-1 root dry weight 12 h-1) and specific root respiratory rate (root respiratory rate, μmol O2 g-1 root dry weight h-1) were determined as indices of root activity. Relative growth rate (RGR, mg g-1 d-1) was used as an index of shoot activity. Compared with IR72, the new lines showed lower RGR and SARN values during the early growth stages. In contrast, during the late growth stages, these activities were higher in the new lines than in IR72. The SARB and sap exudation rate showed a linear correlation with RGR at successive growth stages, regardless of the genotypes and growth conditions. These findings indicated that active root-shoot interaction was maintained throughout the growth period in high-yielding tropical rice, including the new lines and IR72. Therefore, it was considered that SARN and the sap exudation rate are useful indices of root activity regulating RGR in the new lines. However, the root respiratory rate could not be used for selection, because the relationship between RGR and the root respiratory rate changed with the growth conditions. Our findings support the hypothesis that root and shoot activities during maturation are important factors affecting the productivity of the new lines, which have not yet been able to attain the targeted yield.  相似文献   
64.
The N-terminal amino-acid sequence of a major rice phloem-sap protein, designated as RPP23, was determined. The complete amino-acid sequence of RPP23 was deduced from the corresponding rice EST- clone and contained an extra 46 amino acids at the N-terminus, that was apparently cleaved off to form mature RPP23 in sieve tubes. RPP23 shared a similarity to plant small heat-shock proteins (smHSPs), though the N-terminal region of RPP23 was distinct from that of known smHSPs. Immunocytological analyses using leaf sections showed that RPP23 was located only in the phloem regions of leaves, and was present in non-stressed plants. In mature leaves, stronger immunocytological signals were detected in sieve elements than in companion cells.  相似文献   
65.
66.
Analysis of the effect of slow-releasing N fertilizers on microbial parameters of the rhizosphere soil is essential for their effective use. This investigation revealed the comparative effects of oxamide and ammonium sulfate as different N sources on some selected microbial parameters as well as the pH in the rhizosphere of wheat (Triticum aestivum cv. Nourin No. 61). The study was conducted on a Japanese upland alluvial soil using a rhizobox system. In the central compartment (CC) of the rhizoboxes treated with oxamide and ammonium sulfate, four wheat seedlings were grown for 53 d. In either of the treatments, the pH of the rhizosphere soil increased with the increase in the distance from the CC. In contrast, nitrate production, bacterial and fungal numbers, microbial biomass nitrogen, and β-acetylglucosaminidase activity decreased with the increase in the distance, with the highest values of the respective parameters being recorded in the CC. However, remarkable changes of these microbial parameters were found within a distance of 1–2 mm from the CC to the distant compartments. Thus the results indicated that pH, bacterial number, and nitrate production were high in the oxamide treatment. In contrast, higher fungal number, microbial biomass N, and .B-acetylglucosaminidase activity were associated with the ammonium sulfate treatment. It was assumed that the significant (p<O.05) effect of the rhizosphere on microbial activities varied with the treatments.  相似文献   
67.
An apparatus that allows extraction and enrichment of flavor volatiles of rice during cooking using solid-phase microextraction (SPME) was designed and tested in the Japanese rice cultivar Akitakomachi. Because it is a solvent-free technique, no solvent contaminants were extracted during sampling. This technique enables one to place the fiber of SPME in the effluent of the flavor volatiles of the rice during cooking and it can also be used for simultaneous extraction of those volatiles in the course of the cooking process. Therefore, variations in the composition and amount of volatile compounds of rice during cooking can be determined. The overall flavor volatiles of rice during cooking have been analyzed by using this SPME method. Compounds that have been previously highlighted as flavor volatile markers, such as volatiles from oxidative degradation of lipids, products from thermal decomposition, and fatty acids existing in rice, were extracted directly by SPME in conjunction with this apparatus.  相似文献   
68.
Glomerular lipidosis is a disease characterized by lipid accumulation in mesangial cells but that has not been fully investigated in avian species. We examined four wild and two laboratory-reared Japanese rock ptarmigans (Lagopus mutus japonicus)--an endangered avian species--presenting vacuolar deposits in the glomeruli. All cases had vacuolar deposits in the glomeruli. In the wild cases, fewer than 30% of all glomeruli were affected, compared with more than 90% in the laboratory-reared cases. In the wild cases, most deposits were mild and restricted to the mesangial areas of glomeruli. In the laboratory-reared cases, nearly all of the deposits covered entire glomeruli. Electron microscopy of mild deposits revealed vacuoles in the cytoplasm of mesangial cells. These vacuoles were positive for Sudan III, Sudan black B, oil red O, Nile blue, periodic acid-Schiff, Schultz test, and digitonin stain and were negative for performaric acid-Schiff stains. Based on these results, we diagnosed the glomerular lesion as glomerular lipidosis caused by uptake of low-density lipoprotein in mesangial cells. Except for one wild case, all cases exhibited renal tubular oxalosis. The severity of tubular oxalosis tended to be related to the severity of glomerular lipidosis: In cases of mild glomerular lipidosis, tubular oxalosis was also mild or absent. We therefore diagnosed the primary lesion as glomerular lipidosis accompanied by tubular oxalosis. The four wild cases came from different zones and therefore had no opportunities to interbreed and no common relatives. We believe these data support the hypothesis that glomerular lipidosis is a disease of the general population ofJapanese rock ptarmigans. This is the first report of glomerular lipidosis accompanied by renal tubular oxalosis in an avian species.  相似文献   
69.
OBJECTIVE: To determine characteristics of power spectral analysis of heart rate variability (HRV) during a 24-hour period in dogs and to evaluate the effects of vagal and sympathetic tone on HRV ANIMALS: 16 healthy adult Beagles. PROCEDURE: Power spectral analysis of HRV was conducted, using 24-hour ambulatory ECG recordings. Circadian rhythms were evaluated in terms of absolute units of low-frequency (LF) and high-frequency (HF) powers, their ratio (LF:HF), and their adjusted (normalized) units (LF[norm] and HF[norm]). Three or 4 dogs were used for simultaneous measurement of heart rate and respiratory waveform as well as to evaluate treatment (propranolol, atropine, or both) administered to cause blockade of the autonomic nervous system. RESULTS: Values for LF and HF powers, LF:HF, LF(norm), and HF(norm) had obvious rhythmicity in clinically normal dogs. The HF power of HRV in dogs was extremely high, compared with that of other species, and HF peaks corresponded to peaks obtained from respiratory waveforms. Blockade of the autonomic nervous system documented that HRV in dogs was mostly attributable to vagal activity. CONCLUSION AND CLINICAL RELEVANCE: We determined characteristics of power spectral analysis of HRV in dogs, including circadian rhythm of the autonomic nervous system. Power spectral analysis of HRV may provide a useful noninvasive technique for assessing the effect of drugs on activity of the autonomic nervous system in dogs.  相似文献   
70.
Androgen induces production of male effect pheromone in female goats   总被引:1,自引:0,他引:1  
Previously we showed that the primer pheromone responsible for the "male effect" was produced in specific skin regions of castrated male goats by androgen treatments. In the present study, we examined whether androgen can also induce production of the male effect pheromone in female goats. Capsules containing dihydrotestosterone (DHT) or testosterone (T) were subcutaneously implanted into six ovariectomized (OVX) goats for 28 days. Small skin samples were collected from the head and rump regions, and the pheromone activity of their ether extracts was examined using a bioassay that monitors the electrophysiological manifestation of the hypothalamic gonadotropin-releasing hormone pulse generator as multiple-unit activity. Behaviors of OVX goats towards ovary-intact estrous goats were also examined before and at the end of DHT or T treatment. Before androgen treatment, neither the head nor rump skin samples in OVX goats showed pheromone activity. DHT treatment induced pheromone activity in the head skin sample of six OVX goats and in the rump skin sample of two OVX goats. Similar results were obtained by T treatment. In addition, OVX goats treated with T showed masculine-type sexual behaviors such as courtship and mounting behaviors towards the estrous goats. These results demonstrate that androgen is capable of inducing primer pheromone activity in the female and suggest that the synthesis pathway of the male effect pheromone exists in both sexes in the goat.  相似文献   
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