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71.
Adachi I Kusuda S Kawai H Ohazama M Taniguchi A Kondo N Yoshihara M Okuda R Ishikawa T Kanda I Doi O 《The Journal of reproduction and development》2011,57(2):262-266
The purposes of the present study were to establish a noninvasive monitoring assay of fecal progestagen measurement to detect pregnancy and to identify the components of fecal progestagens in early, middle and late pregnancy in cheetahs. Feces were collected from 7 female cheetahs and analyzed from 30 days before the last copulation to parturition in 9 pregnancies. Blood was collected from one cheetah. Fecal progestagen and serum progesterone concentrations were determined by enzyme immunoassay (EIA). The profiles of the fecal progestagen concentrations were similar to the serum progesterone profile. Fecal progestagen and serum progesterone concentrations remained at the baseline until copulation. In the mean fecal progestagen profile during pregnancy (92.8 ± 0.4 days; from the last copulation to parturition), the concentrations increased 3-4 days after the last copulation and remained high until parturition. To investigate changes in the components of progestagen metabolites in the tripartite periods of gestation, fecal progestagens were analyzed by HPLC-EIA. Marked immunoreactive peaks consistent with 5α-pregnan-3α/β-ol-20-one and 5α-pregnan-3,20-dione and small peaks consistent with 5β-pregnan-3α/β-ol-20-one were detected. There were no distinct difference in the components of progestagens among the first, second and third trimesters of pregnancy. The hormone assay, as an indicator of fecal 5α-reduced pregnanes, is useful for detecting pregnancy and monitoring pregnant luteal activity in cheetahs. 相似文献
72.
This study focused on using quartz porphyry (QP) as a water treatment to improve hydroponic production of komatsuna (Brassica rapa L. nothovar; Japanese mustard spinach). We compared the chemistries of the control and QP-treated nutrient solutions and found that magnesium (Mg2+) and calcium (Ca2+) concentrations increased linearly up to day 21 following sowing in both conditions, then declined slightly. The QP treatment reduced sodium (Na+) and chloride (Cl?) concentrations for the whole cultivation period. In both the control and QP-treated solutions, nitrate (NO? 3) and sulfate (SO2? 4) showed the same trend to a daily increase. In spite of these similarities, however, komatsuna production was better with the QP-treated nutrient solution compared to control. Treatment with QP during cultivation in August–September reduced the harmful effects of Na+, chloride (Cl?), nitrite (NO? 2), and SO2? 4 by reducing concentrations of these ions, possibly leading to decreased salinity and toxicity effects in the plants. Mineral concentrations during October–November differed from those of August/September, resulting in variation among the different growth parameters for komatsuna. 相似文献
73.
In the previous paper1) the authors proved that the ferric iron reduction in submerged paddy soils is entirely or mostly effected by the activities of microorganisms in the soil. Prior to the study on the ferric iron reducing microorganisms isolated from the soil, the present paper reports the research for the microbial mechanism of iron reduction. working with the soil itself. 相似文献
74.
Abstract Green manure legumes are often used to compare biomass production as well as nitrogen-fixing capacity. Mineral deficiency often limits the symbiotic nitrogen fixation of many legumes, thus limiting their productivity despite their high yielding potential (O’Hara et al. 1988; Flis et al. 1993). Leguminous species require large amounts of P for growth, nodulation, and nitrogen fixation. Consequently, they are often unable to grow in acid soils with low available P. The low P availability in tropical acid soils often arises from fixation of P by Al and Fe in soil. Generally, Al and Fe-phosphates are relatively unavailable to plants (McLachlan 1976; Ae et al. 1990). 相似文献
75.
Hiromi Yokota Ikuyo Takamura Fumiko Ishikawa Miwako Ohta Shigeki Konishi 《Soil Science and Plant Nutrition》2013,59(2):457-461
It is well known that when inorganic elements such as boron (B), calcium, cobalt, and manganese are added to media in combination or alone, they stimulate the germination and/or tube growth of various kinds of pollen (Schmücker 1933; Loo and Hwang 1944; Yamada 1958; Brewbaker and Kwack 1963). Among these elements, the stimulatory effect ofB is the most effective and generally recognized. Aluminum (Al) belongs along with B to Group IIIa in the periodic table, and Fähnrich and Ultlich (1964) reported that Al inhibited the germination and growth of the pollen tube of Petunia hybrida and Antirrhinum majus. However, stimulatory effects of Al on pollen germination or pollen tube growth had not been previously reported. 相似文献
76.
Satoru Ishikawa Tadao Wagatsuma Tsuyoshi Takano Keitaro Tawaraya Koji Oomata 《Soil Science and Plant Nutrition》2013,59(3):489-501
We investigated the role of the cell wall and plasma membrane (PM) of root-tip cells in Al tolerance in Al-tolerant and Al-sensitive cultivars of five plant species (rice, maize, pea, wheat, and sorghum). No correlation was found between the differences in Al tolerance and the cation exchange capacity of cell walls isolated from root-tips (0–1 em). Preliminary exposure to Al for 1 h was sufficient to inhibit subsequent root re-elongation in an Al-free solution, and the inhibitory effect was more pronounced in the Al-sensitive cultivars than in the Al-tolerant ones. Together with the inhibition of root re-elongation, the PM of the root-tip cells of all the Al-sensitive cultivars was more permeabilized than that of the Al-tolerant cultivars, based on the FDA-PI fluorescence staining technique. Exposure for 30 min to Al treatment at 100 µM significantly increased the PM permeability of protoplasts isolated from the root-tips for the Al-sensitive pea cultivar placed in a moderately hypotonic medium. Protoplasts from root-tip portions of all the Al-sensitive cultivars took up more Al than those of the Al-tolerant ones when treated with 100 pM Al under isotonic conditions for 30 min. The co-existence of DNP or hypotonic conditions led to a larger increase of Al uptake by the protoplasts from Al-sensitive maize cultivars. These results suggest that Al ions rapidly alter the PM of the root-tip portion in the Al-sensitive cultivars, irrespective of plant species, resulting in an increase of the PM permeability. 相似文献
77.
Zhang Jin-Chi Zhuang Jia-Yao Su Ji-Shen Nakamura Hiroyuki Ishikawa Haruyoshi Cheng Peng Fu Jun 《Forest Ecology and Management》2008
Land use plays an important role in soil loss and other environmental problems. Correct prediction of soil loss from different types of land use is very important to land use policy making in the Dabie Mountains, China. Field observations of water and soil loss were carried out in the Shangshe catchment in four types of land use in 1999–2002. This paper reports the study of soil loss in the sub-catchment of Chinese fir forest. 相似文献
78.
Norio Yamagishi DVM PhD Kazutaka Yamada DVM PhD Hiroshi Ishikawa DVM PhD Haruo Yamada DVM PhD 《Veterinary radiology & ultrasound》2000,41(5):422-424
A dog with a bronchocutaneous fistula is described. Contrast enhanced computed tomography was useful for diagnosis and treatment of the fistula in this dog. 相似文献
79.
Recently, riparian forests have attracted attention as they are effective for ecological preservation and landscape enhancement.
Uses of such forests in flood prevention, sediment control, and erosion control works have been actively promoted. This study
aims to clarify the effect of density of riparian trees on drag exerted on trees along river channels under the regime of
bed load transport. Hydraulic model experiments were performed using a straight channel, and the methods to calculate the
drag coefficient necessary for deriving drag exerted on trees were studied. Previous studies have stated that the drag coefficient
of a cylinder is fairly constant when Reynolds number,R
e, is between 103 and 105 (e.g., Schlichting, 1979). This study clarified, however, that in cases of relatively dense arrangements of model trees (cylinders),
the drag coefficient varies greatly with the density of the trees. As such, correlation between the drag coefficient and Reynolds
number was found to be slight. Test results indicated that the drag coefficient of trees,C
d, correlates strongly with the coefficient of velocity,U′/U
*
′, friction factor of the channel bed,f′, and roughness concentration of trees × flow depth,aH′ or ratio of the area occupied by trees,λ. Furthermore, the drag coefficient,C
d, was also found to be slightly correlated with the gradient of the channel bed,I. Equations using either of the following parameters were obtained for deriving the drag coefficient,C
d, based on the experiment results:aH′; λ; U′/U
*
′; and Froude numberF
r. These equations allow fairly accurate calculation of drag exerted on trees. 相似文献