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以薄壳山核桃‘Shaoxing’和‘Pawnee’的花粉为材料,采用MTT染色法对其4个散粉时期的花粉活力及不同储藏条件下的花粉活力变化进行了研究,筛选出最佳花粉收集时期和最佳储藏条件。结果表明:(1)‘Shaoxing’和‘Pawnee’不同散粉时期花粉活力由高到低变化规律都为:散粉盛期>散粉初期>即将散粉期>散粉末期。(2)‘Shaoxing’和‘Pawnee’各散粉期的花粉活力随阴干时间的延长而下降,其中‘Shaoxing’盛花期、‘Pawnee’散粉初期的花粉在0~4 d的短时间阴干储藏下降速率最慢,96 h后分别仍有45.70%和64.31%;(3)低温、干燥的储藏条件有利于‘Shaoxing’和‘Pawnee’花粉活力的保持,2个品种的花粉在不同储藏条件下都表现为:?80 ℃密封干燥>?80 ℃密封>4 ℃密封干燥>4 ℃密封>常温密封干燥>常温密封,其中2个品种的花粉在?80 ℃条件储藏30 d后活力仍保持在60%以上,而常温条件储藏30 d后的花粉活力低于20%,储藏80 d就完全失去活力。 相似文献
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MASAAKI TACHIBANA KAZUYUKI ITOH HIROAKI WATANABE SOICHI NAKAYAMA 《Weed Biology and Management》2010,10(1):9-15
This study was conducted to determine the reproductive characteristics of Barbarea vulgaris under different disturbance regimes (mowing and tilling) in two different habitats: a levee and a wheat field. On the levee, 77 of the 114 individuals that had had their floral stalks removed by the first mowing produced new rosettes at the basal part of the stem during the same growing season. The plants that were mowed four times per year had a significantly greater survival rate than the plants that were mowed twice per year. The levee population that was mowed without tillage was largely maintained by vegetative reproduction. These results suggest that mowing the levees promotes the vegetative reproduction of B. vulgaris and helps it to compete with tall-growing plants, thus facilitating its survival as a perennial. In spite of the high sprouting ability of the plant's root fragments, most of the root fragments did not regenerate when buried or when exposed to high soil moisture conditions in tilled wheat fields. The population of B. vulgaris in tilled wheat fields was maintained almost entirely by sexual reproduction. Barbarea vulgaris can survive under two different management regimes by altering its mode of reproduction. 相似文献
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Natsuko NAKAYAMA Takashi TSUGE Susumu ASAKAWA Makoto KIMURA 《Soil Science and Plant Nutrition》2009,55(1):53-64
Members of the Sphingomonas -related genera ( Sphingomonas , Sphingobium , Novosphingobium and Sphingopyxis ) are dominant in bacterial isolates from the floodwater of Japanese paddy fields. Fifty-eight Sphingomonas / Novosphingobium bacteriophages (phages) were isolated to elucidate their morphology, host range and phylogenetic diversity based on the capsid gene ( g23 ) sequence. All of the phages were siphoviruses with isometric or elongated, icosahedral capsids and a long, non-contractile tail. The genomes were double-stranded DNA measuring either 40, 60, 100 or 160 kb. The host range of the phages was examined by infecting 16 bacterial isolates from the floodwater, belonging to Sphingomonas , Novosphingobium , Sphingopyxis and Porphyrobacter . The host range was widely different and varied between infection of only the host used for isolation and infection of hosts belonging to the three genera of Sphingomonas , Novosphingobium and Porphyrobacter . All phages had g23 , indicating the ubiquity of the g23 gene among Myoviridae and Siphoviridae members. Every g23 sequence of the phages belonged to one of the six uncharacterized Paddy Groups proposed by Fujii et al . (2008 ). The g23 sequences were identical at the nucleotide level for several phages with isometric and elongated capsids with 60 and 160 kb genomes, and between some phages and the clones that were retrieved from distant paddy fields. This indicates the common occurrence of horizontal transfer of g23 in the paddy fields. The g23 sequence does not correlate with the host range of those phages. In addition, a larger degree of divergence of g23 from coliphage T4 in paddy fields compared to marine environments was estimated from the present study. 相似文献
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HIROSHI TANAKA MASANARI NAKAYAMA KATSUAKI TAKASE 《Veterinary radiology & ultrasound》2006,47(1):99-102
Ultrasonography was performed during spinal surgery on two dogs that were suspected of having intramedullary lesions by myelography and magnetic resonance imaging. Ultrasonographically, the pathologic conditions of the spinal canal or cord were adequately imaged during surgery in both dogs. On the basis of ultrasonographic findings, a biopsy was obtained in Patient 1 and removal of the lesion was accomplished in Patient 2. Histopathologic diagnosis was myelomalacia in Patient 1 and spinal nephroblastoma in Patient 2. Intraoperative ultrasonography was demonstrated to be suitable for detecting intradural conditions, and, thus, is valuable for increasing the accuracy of biopsies or completeness of resections of intramedullary lesions. 相似文献
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Aksorn SAENGTIENCHAI Yoshinori IKENAKA Wageh Sobhy DARWISH Shouta M.M. NAKAYAMA Hazuki MIZUKAWA Mayumi ISHIZUKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1261-1267
Pyrene (PY) is a polycyclic aromatic hydrocarbon (PAH) that is often used as a biomarker
for human and wildlife exposure to PAHs. As the metabolites of PAHs, similar to their
parent compounds, pose public health risks, it is necessary to study their characteristics
and tissue-specific distribution. The present study was performed to experimentally
characterize PY metabolites and analyze the tissue-specific distribution of the conjugated
metabolites after oral administration of PY to rats. PY metabolites, such as
pyrenediol-disulfate (PYdiol-diS), pyrenediol-sulfate (PYdiol-S), pyrene-1-sufate (PYOS),
pyrene-1-glucuronide (PYOG) and 1-hydroxypyrene (PYOH), were detected in rat urine.
Although glucuronide conjugate was the predominant metabolite, the metabolite composition
varied among tissues. Interestingly, the proportion of PYOH was high in the large
intestine. Furthermore, PYOH was the only PY metabolite detected in feces. 相似文献
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Yousuke MURATA James Kenn CHAMBERS Kazuyuki UCHIDA Ko NAKASHIMA Yasuko HANAFUSA Mitsutaka IKEZAWA Takashi SUGITA Hiroyuki NAKAYAMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(10):1285-1288
A 10-year-old castrated male mixed-breed dog exhibited vomiting, lethargy and anorexia.
An abdominal ultrasound examination revealed a focal dilation of the abdominal aorta. The
dog died 2 days after examination, and necropsy revealed a ruptured aneurysm at the
abdominal aorta between the kidneys. Histological examination revealed severe
granulomatous and necrotizing pan-arteritis with fungal organisms.
Graphium species was identified through DNA sequence analysis of the
PCR product from formalin-fixed paraffin-embedded samples. To our knowledge, this is the
first report of aortic aneurysm caused by Graphium species in a dog. 相似文献
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Nanako USHIO Ken-ichi WATANABE James K. CHAMBERS Tokuhiro SHIBATO Hiroyuki NAKAYAMA Kazuyuki UCHIDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(11):1523-1526
A rock pigeon (Columba livia) caught in Akihabara, Tokyo, showed
neurological symptoms, such as head tilt and circling. Pathological examinations revealed
abundant Sarcocystic cysts in the skeletal muscle and myocardium with mild myositis, and
numerous schizonts and sarcocysts with severe multifocal granulomatous T-lymphocytic
infiltration in the central nervous system. A Sarcocystis
calchasi-specific gene was detected in the muscle and brain. This case indicates
S. calchasi was distributed in Japan and caused severe encephalitis to
rock pigeons. 相似文献
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