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1.
A 14‐month‐old Japanese Black heifer was evaluated on Day 0 (D 0) for enlargement of the right ovary (RO). Transrectal ultrasonography (TRUS) revealed that the RO was markedly enlarged and multicystic, while the left ovary (LO) was small and inactive. The presumptive diagnosis was granulosa‐theca cell tumour (GTCT), which was confirmed by markedly elevated plasma anti‐Müllerian hormone (AMH) of 4.42 ng/ml. Therefore, ovariectomy of the RO was the treatment of choice. The heifer was checked by TRUS and blood sampling on D 42, D 63 and immediately before ovariectomy on D 85. On D 42, TRUS did not show marked changes in either ovary in comparison with D 0. However, on D 63, the RO had transformed into a single cyst, and on D 85, the LO had resumed cyclic activity. The RO was extracted on D 85 by hand‐assisted laparoscopic ovariectomy to allow better control. Unexpectedly, histopathology revealed the lesion to be a fluid‐filled cystic structure, with no neoplastic proliferation of follicular epithelium that would indicate GTCT. The wall of the cystic structure consisted of collagen fibres and a few degenerated granulosa cells. The retrospective hormonal analysis revealed that the AMH concentrations had markedly dropped on D 63 and 85, which coincided with resumption of cyclicity in the LO. These findings suggest that the GTCT had self‐cured and transformed into a cyst‐like structure. The heifer then received an oestrous synchronization regime on D 105, was artificially inseminated on D 115 and became pregnant.  相似文献   
2.
The inhibitory effects of 102 methanol extracts of 40 mycelia, 9 culture fluids, and 53 fruiting bodies of 40 strains of Ganoderma lucidum on 5-reductase were investigated. The methanol extract of the fruiting body of each strain was found to show the strongest 5-reductase inhibitory activity among the extracts tested.  相似文献   
3.
Comparative virulence of blue-stain fungi isolated from Japanese red pine   总被引:2,自引:0,他引:2  
 We made inoculations to determine the comparative virulence of blue-stain fungi isolated from Japanese red pine (Pinus densiflora Sieb. & Zucc.). Based on the symptoms caused by each fungus, the most virulent fungus was Leptographium wingfieldii. Also, Ophiostoma minus was relatively virulent while lesions induced by some species did not differ from those in the control treatment. Based on the results, we concluded that the pathogenicity of the blue-stain fungi varied widely, and thus their impact on the host most likely varies too. Received: June 7, 2002 / Accepted: October 4, 2002 Present address: JST Domestic Research Fellow, Forest Pathology Laboratory, Tohoku Research Center, Forestry and Forest Products Research Institute, 92-25 Nabeyashiki, Shimo-Kuriyagawa, Morioka 020-0123, Japan Tel +81-19-648-3961; Fax +81-19-641-6747 e-mail: H_masu@hotmail.com Acknowledgments We thank Drs. Ohtaka and Usuki, Plant Pathology and Mycology Laboratory, Institute of Agriculture and Forestry, University of Tsukuba, for technical assistance. Contribution No. 174, Plant Pathology and Mycology Laboratory, Institute of Agriculture and Forestry, University of Tsukuba. Correspondence to:H. Masuya  相似文献   
4.
(-) Hydroxycitric acid (HCA), an active ingredient extracted from the Garcinia cambogia fruit rind, has been commonly used as a dietary supplement for weight management. Given the controversy over HCA related testicular toxicity in animal studies, we investigated changes in serum sex hormones levels as an extension of our previous double-blind placebo-controlled trial in human subjects, in which 44 participants received either G. cambogia extract (1667.3 mg/day equivalent to 1000 mg HCA/day) or placebo for 12 weeks. Compared to the placebo group, administration of the extract did not significantly alter the serum testosterone, estrone, and estradiol levels. Similarly, hematology, serum triacylglycerol and serum clinical pathology parameters did not reveal any significant adverse effects. The results of this preliminary investigation indicate that ingestion of G. cambogia extract at dose levels commonly recommended for human use does not affect serum sex hormone levels and blood parameters.  相似文献   
5.
Relationships between tree mortality and bark beetle infestation onAbies veitchii at the wave-regenerated forest in Mt. Asahi, Okuchichibu area were investigated. Most of the firs with green needles and newly developed current year’s shoots in the dieback zone were heavily infested by bark beetles before the death of the trees. After heavy infestation of beetles, about half of the infested firs died within the year, and the other half died in the next year. When the species composition of bark beetles and associated ophiostomatoid fungi were investigated in Mt. Asahi and also at a typical wave-regenerated forest in Mt. Shimagare, Yatsugatake area,Cryphalus montanus andC. piceae were dominant beetle species for Mt. Asahi and Mt. Shimagare, respectively.Ophiostoma subalpinum andO. europhioides were dominant fungal species at both wave-generated forests. BecauseO. subalpinum was detected more frequently from deeper areas of sapwood thanO. europhioides, it was suggested that the fungal species may accelerate the death of stressed firs in wave-regenerated forests. Contribution No. 169, Laboratory of Plant Parasitic Mycology, Institute of Agriculture and Forestry, University of Tsukuba.  相似文献   
6.
To clarify the effects of temperature on the recruitment of chub mackerel (Scomber japonicus) in the North Pacific, we investigated the influence of winter surface temperature (WST) on spawners at the time of maturity around the spawning grounds and the influence of ambient spring temperature on larvae using estimated temperature (ET) obtained from particle tracking experiments. We found a significant positive correlation between ET approximately 10 days following hatching and the recruitment per spawning stock biomass (RPS) after 2000. The closer (more meandering) the Kuroshio Current (KC) axis was in relation to the spawning ground, the higher (lower) the spring surface temperature and the higher (lower) RPS was in the spawning ground. In contrast, WST inside KC near the maturity/spawning ground was significantly negatively correlated with RPS. A significant negative correlation between the temperatures in winter and spring was detected in the area after 2000, when the conditions of the Pacific decadal oscillation index and the stability of the Kuroshio Extension were synchronous, indicating that KC shifted northward during this time. The reversed temperature pattern was consistent with the winter–spring movement of KC axis in the offshore direction and was correlated with the winter–spring difference in the intensity of the Aleutian low. These results suggest that the annual variation in chub mackerel recruitment after 2000 was strongly affected by the combined effects of ambient temperature because of the reversal of conditions that occurred between winter and spring around the maturity/spawning ground, which was related to the KC path.  相似文献   
7.
Y. Kaneko    H. Yano    S. W. Bang  Y. Matsuzawa 《Plant Breeding》2001,120(2):163-168
Breeding of Raphanus sativus‐Brassica rapa monosomic chromosome addition lines (MALs, 2n = 19) was carried out by backcrossing the synthesized amphidiploid line, Raphanobrassica (R. sativus×B. rapa, 2n = 38, RRAA, line RA89) with R. sativus cv. ‘Shogoin’ (2n = 18, RR). In the first cross of Raphanobrassica× radish, four sesquidiploidal BC1 plants (2n = 28, RRA, RA89‐36‐1, RA89‐31‐1, RA89‐31‐2, RA89‐31‐3) were successfully developed. In these plants, the chromosome configurations of 9II + 10I and 10II + 8I were observed frequently at first metaphase (MI) of meiosis in pollen mother cells (PMCs). The RA 89‐36‐1 plant produced many seeds in the reciprocal backcrosses with radish. About 50% of the BC2 plants obtained from the cross of RA89‐36‐1 plant × radish were 2n = 19 plants, followed by 2n = 18 plants (24%) and 2n = 20 plants (19%). In the reciprocal cross, 2n = 19 plants were also developed at the rate of 40%. From analysis of specific morphological traits, 2n = 19 plants were classified into eight types (a‐h). When 25 selected primers were used in polyacrylamide gel electrophoresis, random amplified polymorphic DNA (RAPD) markers derived from B. rapa for each type of MAL were detected in numbers between three for e‐type and 16 for b‐type. RAPD markers specific for each type alone were from one (OPE 05‐344) for h‐type to nine for b‐type. In the g‐type, no marker specific to this type alone was observed. However, 19 bands were common between at least two types. These MAL plants exhibited predominantly the chromosome configuration of 9II + 1I at MI of PMCs, pollen and seed fertility being the same level as the radish cv. ‘Shogoin’. From the morphological traits and DNA markers, eight different MAL types among 10 expected were identified.  相似文献   
8.
Y. Kaneko    N. Nagasawa    S. W. Bang  Y. Matsuzawa 《Plant Breeding》2002,121(2):171-173
Eight plants of the putative double monosomic addition line (DMAL, 2n= 20) were developed by crossing a monosomic chromosome addition line of radish [f(A)‐type monosomic addition line (MAL) (2n= 19)] carrying the f chromosome of Brassica rapa (2n= 20, AA) with another [e(C)‐type MAL (2n= 19)] having the echromosome of Brassica oleracea (2n= 18, CC). The homoeological relationships between the two alien chromosomes were investigated by morphological, cytogenetic and random amplified polymorphic DNA (RAPD) analysis. Seventeen morphological traits that were not present in the radish cv. ‘Shogoin’ were observed in both MALs and these traits were substantially exhibited in DMAL plants. At the first metaphase of pollen mother cells (PMCs), the two parental MALs showed a chromosome configuration of 9II +1I, demonstrating impossibility of recombination between the R and the added chromosomes. The DMALs formed 10II in approximately 73% of PMCs, with one bivalent showing loose pairing between two chromosomes differing in size. In an attempt to identify the two MALs by RAPD‐specific markers using 26 selected random primers, 13 and 20 bands were specific for the f(A)‐type and the e(C)‐type MALs, respectively; 12 bands were common to both MALs (26.7%). In conclusion, the f chromosome of B. rapa is homoeologous to the e chromosome of B. oleracea. The genetic domain (genes) for 17 morphological traits are linked to each homoeologous chromosome bearing 27% of the corresponding RAPD markers.  相似文献   
9.
Freely available glucose improves the conditions for soil microorganisms which are utilized as food by Collembola. We examined the effects of glucose application on collembolan (Folsomia candida Willem) growth and on several biotic and abiotic soil parameters (microbial biomass, soil respiration, qCO2, dissolved organic carbon, inorganic nitrogen, and Olson-P) in an artificial system without predatory pressure on Collembola. Glucose addition increased soil respiration and qCO2, and decreased nutrient levels in the soil. Collembolan growth increased with increasing glucose doses. We conclude that the availability of carbon substrates can sustain collembolan growth via an improvement of microbial growth conditions.  相似文献   
10.
Nonenzymatic reduction of dehydroascorbate into ascorbate by the reduced form (quinol form) of 2-amino-3-carboxy-1,4-naphthoquinone, a strong growth stimulator for bifidobacteria, has been found. The bimolecular reaction rate constant was evaluated as 9 M(-)(1) s(-)(1) at pH 7.0. This reaction has been successfully coupled with enzymatic regeneration of the naphthoquinol by NAD(P)H in cell-free extracts of Bifidobacterium longum 6001. The overall reaction is a regeneration of NAD(P)(+) by dehydroascorbate [or a regeneration of ascorbate by NAD(P)H], in which the naphthoquinone/quinol redox couple functions as an electron transfer mediator. Kinetic study of the reduction of dehydroascorbate with related quinol compounds suggested the significance of the amino substituent of the naphthoquinol. A mechanism of the electron transfer from the quinol to dehydroascorbate is proposed, where the first step of the reaction is a nucleophilic addition of the C(2)-amino substituent of the naphthoquinol to the C(2)-position of dehydroascorbate to form a Schiff base intermediate.  相似文献   
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