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41.
Hydrogen sulfide causes offensive odors. We attempted to isolate sulfur oxidizing bacteria (SOB) from cattle manure compost. A most probable number assay could not detect SOB by using a Cha medium which had been applied in order to isolate the SOB from active sewage. Cultivation using a Cha plate medium revealed 5.75 × 107 colony forming unit/g of bacteria. A single strain of SOB was isolated from a colony formed on the plates and identified as Halothiobacillus neapolitanus. This is the first report that H. neapolitanus has been found in cattle manure compost.  相似文献   
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Takeshi  TOMIYAMA  Koichi  SASAKI  Michio  OMORI 《Fisheries Science》2004,70(4):531-536
ABSTRACT:   The purpose of the present paper was to examine the size relationship between the juvenile stone flounder Platichthys bicoloratus and the bivalve Nuttallia olivacea , the siphon of which is important prey for the juvenile flounder. Juvenile stone flounder feed mainly on tips of the inhalant siphon of the bivalve. The maximum width of siphon tips in the stomach contents of age-0 fish could not reach that of age-1 fish, although the siphons in age-0 fish became larger as they grew. This size discrepancy indicated a limitation in the size of bivalves available to juveniles. The proportion of total cropping frequency for the siphon of the bivalve by juveniles was estimated according to the bivalve size class. Most bivalves that had cropped siphon tips ranged from 5 to 30 mm in shell length. The total cropping frequency per bivalve was particularly intense on bivalves of 10–25 mm shell length in spite of their small proportion of 24.9% of the total. This frequency intensity indicated that the size of bivalves with cropped siphons by juvenile stone flounder might depend on the ability of juveniles rather than the size composition of the bivalves.  相似文献   
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In this study, we examined the existence and structure of areolae and the steroidogenesis of areolar trophoblast cells in the Antarctic minke whale placenta morphologically and immunohistochemically. Placentas were collected from the 15th, 16th and 18th Japanese Whale Research Program under Special Permit in the Antarctic (JARPA) and 1st JARPA II organized by the Institute of Cetacean Research in Tokyo, Japan. The opening and cavity of fetal areolae formed by taller columnar trophoblast cells (areolar trophoblast cells) with long microvilli and a bright cytoplasm, as compared with the trophoblast cells of the chorionic villi interdigitating with the endometrial crypts, were recognized in observations of serial sections. The opening of the areolar cavity was hidden by chorionic villi with areolar trophoblast cells. Furthermore, a closed pouch-like structure lined by tall columnar cells similar to areolar trophoblast cells within the stroma of chorionic villi was noticed and continued to the areolar cavity, with the opening seen on serial sections. In a surface investigation of the chorion and endometrium by SEM, maternal (endometrial) areolae irregularly surrounded by endometrial folds were obvious. Moreover, we distinguished areolar trophoblast cells with long microvilli attached with many blebs from trophoblast cells. In our immunohistochemical observations, a steroidogenic enzyme, cytochrome P450 side chain cleavage enzyme (P450scc), was detected with strong immunoreactivity in trophoblast cells. However, areolar trophoblast cells showed weak or no immunoreactivity for P450scc.  相似文献   
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In the present study, we examined the development to blastocysts of large and small blastomeres from unevenly cleaved 2‐cell embryos (uneven 2‐cell embryos) in pigs. Proportion of blastocysts derived from large blastomeres (52.8 ± 6.4%) was significantly higher (P < 0.05) compared with small ones (32.1 ± 4.6%). However, there were no differences in total cell number, inner cell mass (ICM) cell number and ICM/total cells ratio between them. Of 53 sister blastomere pairs in the same embryos examined there were 12 pairs (22.6%) in which both blastomeres developed to blastocysts, 16 pairs (30.2%) in which only large blastomeres developed to blastocysts, and five pairs (9.4%) in which only small blastomeres developed to blastocysts. Relative total amount of active mitochondria in small blastomeres were lower (P < 0.05) than that of large blastomeres and blastomeres from evenly cleaved 2‐cell embryos. However, there was no difference in relative density of active mitochondria in these three types of blastomeres. In conclusion, blastocysts derived from small and large blastomeres in uneven 2‐cell embryos had comparable quality in terms of cell number, ICM number, ICM/total cell ratio and distribution of active mitochondria. The results suggest that these blastomeres may contribute multiple offspring production in pigs.  相似文献   
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Measurement of urinary metanephrines in spot samples is used for the diagnosis of canine pheochromocytoma (PC). We describe a simple analytical method based on liquid chromatography tandem mass spectrometry (LC-MS/MS) for measuring free metanephrine (MN) and normetanephrine (NMN) in spot urine samples. Using the developed method, we evaluated the stability of urinary free-MN and free-NMN at various storing conditions. In addition, we assessed the feasibility of urinary free-MN and -NMN measurement for diagnosing PC. Urine samples were mixed with stable isotope internal standards and thereafter purified by ultrafiltration. The purified samples were analyzed by LC-MS/MS in the multiple reaction monitoring mode after separation on a multimode octa decyl silyl column. The coefficient of variation of free-MN and -NMN measurement was 7.6% and 5.5%, respectively. The linearity range was 0.5–10 µg/l for both analytes. Degradation was less than 10% for both analytes under any of the storage conditions. The median free-NMN ratio to creatinine of 9 PC dogs (595, range 144–47,961) was significantly higher (P<0.05) than that of 13 dogs with hypercortisolism (125, range 52–224) or 15 healthy dogs (85, range 50–117). The developed method is simple and may not require acidification of spot urine. The results of this preliminary retrospective study suggest that the measurement of urinary free metanephrines is a promising tool for diagnosing canine PC.  相似文献   
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