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71.
72.
This study characterised muscle fibres in trunk, forelimb and hindlimb muscles of three bat species: little Japanese horseshoe (Rhinolophus cornutus), greater horseshoe (Rhinolophus ferrumequinum) and Egyptian fruit (Rousettus aegyptiacus). Twenty-seven muscles from trunk, forelimb and hindlimb were dissected, weighed and analysed by immunohistochemistry and sodium didecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and determined their cross-sectional areas (CSA). Results showed that Type IIa and Type IIa/x made the highest proportion of total muscle mass. Moderate proportion was formed by Type IIb. Type I and IIx appeared at very low levels in all bats. Type IIb was the only fibre type detected in patagial muscles in wing membrane of greater horseshoe while other fibre types were not observed. Type I muscle fibres were very few and appeared infrequently in fifteen muscles of Egyptian fruit and in only one muscle in each, greater horseshoe and little Japanese horseshoe. Type IIx was also detected in three muscles in greater horseshoe and only one muscle in Egyptian fruit but none in little Japanese horseshoe. The highest average CSA μm2 was detected in Type IIb and values were 734.2μm2 for LHB; 1537.9μm2 for GHB and 1,720.9μm2 for EFB. Lowest and undetermined values were observed for Type I and IIx. These data demonstrate that Type IIa, IIa/x and IIb form significant proportion of adult bat muscle mass and Type IIb is the largest fibre type. The distribution pattern is suggestive of specialised functions of the fibres in relation to orientation and speed of bats during flight.  相似文献   
73.
Factors that affect the δ13C values of fungi need to be analyzed for the progress of isotope-based studies of food-chain or organic matter dynamics in soils. To analyze the factors that control δ13C values of the fungal body, basidiomycete and ascomycete species were grown on a beechwood substrate (six species) and in glucose medium (nine species), and the δ13C value of produced fungal body was compared to that of the carbon source. The 13C enrichment (Δδ13C) in the fungal aggregates compared to the decomposed wood varied from 1.2 to 6.3‰ among six species. In the glucose substrate experiment, the degree of 13C enrichment in the hyphal mat was relatively small and varied from −0.1 to 2.8‰ among nine basidiomycetes species depending on their growth stage. Calculated δ13C values of the respired CO2 were lower than those of the hyphal mat, organic metabolites and the glucose used. The degree of 13C enrichment was affected by fungal species, substrate and growth stage. Fungal internal metabolic processes are the plausible mechanism for the observed isotopic discrimination between fungal bodies and substrates. Especially, dark fixation of ambient CO2 and kinetic isotope fractionation during assimilation and dissimilation reactions could well explain Δδ13C dynamics in our experiments. Through the analysis of field Δδ13C, we could know undisturbed fungal status about starvation, aeration and type of decomposition.  相似文献   
74.
beta-Lactoglobulin A (beta LG A) modified with N-ethylmaleimide (NEM-beta LG A) was purified by ion exchange chromatography, and modification of beta LG A by NEM was confirmed by time of flight mass spectrometry and 5,5'-dithiobis(2-nitrobenzoic acid) methods. The fluorescent spectrum of NEM-beta LG A was slightly different from that of native beta LG A. NEM-beta LG A gave no polymerization after heating at 80 degrees C and pH 7.5, as shown by polyacrylamide gel electrophoresis. Conformational change of NEM-beta LG A was observed at 80 degrees C by ultraviolet differential spectra, whereas after cooling it recovered to its original state as before heating, indicating apparent reversible thermal denaturation. Native beta LG A is resistant to pepsin hydrolysis, whereas heated beta LG A was easily hydrolyzed by pepsin. NEM-beta LG A before heating was also resistant to pepsin hydrolysis, and after heating NEM-beta LG A was still resistant to pepsin hydrolysis. These results indicate that NEM-beta LG A maintained a conformation similar to its native form even after heating. Addition of 0.2 M NaCl to the beta LG A heated under salt-free condition induced polymerization of heated beta LG A molecules, but not that of heated NEM-beta LG A. This seemed to indicate that the formation of inter- or intramolecular disulfide linkage made the heat-induced conformational change of beta LG A irreversible.  相似文献   
75.
Indonesian soy sauce is made using only soybeans as the nitrogenous source. Moromi obtained from fermentation of yellow soybeans using Aspergillus sojae as the starter was investigated. The fraction with molecular weights of less than 500 Da obtained by stepwise ultrafiltration was then fractionated by several chromatographic procedures, including gel filtration chromatography and RP-HPLC. Several chemical analyses, CE profiles, and taste profiles were performed to obtain the most intense umami fraction. The main components eliciting or enhancing the umami taste present in the fraction were purified and identified by protein sequencing, ESI-MS, and (1)H NMR at 400 MHz. Besides free l-glutamic acid and aspartic acid, free aromatic amino acids such as l-phenylalanine and l-tyrosine may also play an important role in impressing savory or umami taste of Indonesian soy sauce at their subthreshold concentrations and in the presence of salt and free acidic amino acids. This is reported as a new phenomenon of the so-called bitter amino acids.  相似文献   
76.
ABSTRACT:   The synergetic effects of an immobilized cell system in an oleophilic polyurethane foam (PUF) and use of a thermotolerant strain on degradation of hydrocarbons by colorless green microalga Prototheca zopfii are reported. Two strains of P. zopfii , i.e. thermotolerant RND16 and non-thermotolerant ATCC30253, were immobilized in PUF to compare their abilities to biodegrade a mixed hydrocarbon substrate (MHS) containing aliphatic and polycyclic aromatic hydrocarbons (PAHs), as a function of temperature. The thermotolerant strain RND16 degraded MHS at 35°C, while ATCC30253 did not degrade hydrocarbons at temperatures higher than 30°C. Immobilization of P. zopfii in PUF resulted in shortened lag for growth-associated biodegradation of n -alkanes in MHS, the effect of which was most significant in cultures of RND16 at 25°C. Nevertheless, the decrease in the amount of degraded PAHs was caused by PUF immobilization and the level of this decrease was marked in the cultures of RND16, in which rate and extent of n -alkane degradation were higher than for ATCC30253.  相似文献   
77.
The prevalence of Dirofilaria immitis in free-ranging raccoon dogs (Nyctereutes procyonoides viverrinus) was examined in the southeast region of Kanagawa Prefecture, Japan, using a rapid immunomigration (RIM) test kit. Between April 2007 and March 2010, we examined 108 raccoon dogs rescued and housed by the Kanazawa Zoological Garden. D. immitis infection was found in 8 (7.4%) raccoon dogs. This is the first report to reveal the prevalence of D. immitis infection in living raccoon dogs. The prevalence of the infection was lower than previously reported values obtained on postmortem examination. One reason might be that the present study included young raccoon dogs infected with immature worms. Significant high-risk areas of D. immitis infection in the raccoon dogs were not observed.  相似文献   
78.
A diagnosis of acute myeloid leukemia was made in a 10-month-old Holstein female calf. The leukemia was macroscopically characterized by great enlargement of the spleen and moderate enlargement of some lymph nodes. Histochemical and immunohistochemical examination disclosed the presence of neoplastic cells either containing metachromatic and tryptase-positive granules or expressing factor VIII-related antigen. The granules, which were positive for naphthol AS-D chloroacetate esterase and did not have particulate contents, were distinct from those of basophilic leukemia cells. This leukemia was thought to be derived from a common myeloid progenitor capable of giving rise to megakaryocyte-erythrocyte progenitors and granulocyte-monocyte progenitors with the ability to differentiate into mast cells.  相似文献   
79.
Rubus seed has a deep double dormancy that restricts germination due to seed coat structure and chemical composition. Improved germination of diverse Rubus species required for breeding improved blackberry and raspberry cultivars is partly dependent on the seed coat structure. This study evaluated the seed coat structure of three species with thin (R. hoffmeisterianus Kunth & C. D. Bouché), medium (R. occidentalis L.) and thick (R. caesius L.) seed coats. The three species exhibited distinctive seed-coat cell composition. The very thin testa (0.086 mm) of R. hoffmeisterianus had little exotesta (surface) reticulation; with the meso- and endotesta composed of sclereids of homogenous shape and size. R. occidentalis had a thick testa (0.175 mm) and a highly reticulate exotesta; the meso- and endotesta were composed of several diverse types of sclereids. R. caesius had the thickest seed coat (0.185 mm) but only moderate exotesta reticulation; the meso- and endotesta were composed of large, irregular, loosely arranged sclereids. R. occidentalis, a medium size seed, was the most heavily lignified with seed-coat thickness similar to R. caesius, the largest seed. Proanthocyanidins (PAs) from dry seed of six Rubus species were extracted and quantified by high performance liquid chromatography. R. hoffmeisterianus, a thin only slightly hard seed, had half the PA (0.45 μg/seed) of R. occidentalis with a thick, extremely-hard seed coat and diverse sclereids (1.07 μg/seed). PA content and sclereid composition both appear contribute to seed coat hardness and resulting seed dormancy. The effectiveness of sulfuric acid for Rubus seed scarification is likely due to degradation of PAs in the testa.  相似文献   
80.
1. Chronic administration of a glycoprotein fraction from chicken pituitary using an ALZET osmotic pump at 12.5 micrograms/h for 2 weeks induced growth of ovarian follicles to a mature size in the ovary and deposition of yolk in sexually immature 6-week-old Japanese quail females which were kept under 8L:16D short-day conditions. However, no ovulation was induced in these birds. 2. Injection of 500 micrograms of the glycoprotein into other immature short-day females was performed following the above chronic administration, 12 or 14 and 15 d after implantation of the osmotic pump. About 24 h after injection, 3 of 14 females laid one or two eggs. Ovulation was confirmed in 4 females by autopsy. A total of 5 of 14 females ovulated 6 eggs, and significant development of the oviduct and the cloacal opening were observed in all of the treated females. 3. Thus, complete ovarian function could be induced in sexually immature female Japanese quail by administration of avian gonadotrophin using a combination of an osmotic pump and an injection.  相似文献   
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