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991.
Kazuhiko Masaka Hajime Sato Hirokazu Kon Hiroyuki Torita 《Journal of Forest Research》2010,15(6):374-383
To assess and improve methods for the development of coastal forests in Hokkaido, northern Japan, this study examined the
factors affecting mortality of planted Pinus thunbergii Parlat. saplings in a region with seasonal soil frost. The needles of pine saplings at the study site turn red in late spring,
suggesting xylem embolism, which can lead to death. Sapling mortality was strongly correlated with the degree of cold just
after planting and with the occurrence of repeated severe winters. Volcanic ash soil had been supplied to improve the soil
nutrients, and the volcanic ash soil always thawed later than the original coastal sand. Saplings in volcanic ash were significantly
more damaged than those in original coastal sand. This suggests that hydraulic stress caused by cuticular transpiration under
frozen soil conditions during spring may also accelerate damage due to embolisms. Hence, volcanic ash soil should not be applied
to soils in regions with seasonal soil frost. A covering of woodchips can help prevent frost from reaching greater soil depths,
and, indeed, fewer saplings at the study site died in areas with such coverage. Planting location can also affect pine sapling
mortality. For example, shading caused by wood fencing may affect the soil freezing profile during winter; therefore, planting
close to a fence should also be avoided in regions with seasonal soil frost. These findings should be used to improve the
development of forests in regions with seasonal soil frost. 相似文献
992.
Takeuchi Y Iizuka H Kanemitsu H Fujino Y Nakashima K Uchida K Ohno K Nakayama H Tsujimoto H 《Journal of Feline Medicine and Surgery》2010,12(12):982-987
A 10-year-old American Shorthair cat with nasal discharge, anorexia, and weight loss was found to have pancytopenia and hyperproteinaemia. Bone marrow aspiration revealed atypical plasma cells that totalled 50% of the nucleated bone marrow cells. The number of atypical plasma cells progressively increased in the peripheral blood during the observation period of 64 days. The cat did not respond to treatments with melphalan, chlorambucil, and prednisolone, and died 71 days after the initial presentation. Clinical, cytological, histopathological, and immunohistochemical findings in this case supported the diagnosis of myeloma-related disorder (MRD) with leukaemic progression. 相似文献
993.
994.
Li Chang-qing Alatengdalai Xue Shu-yuan Atsushi Asano Atsushi Tajima Naoto Ishikawa 《东北农业大学学报(英文版)》2017,24(1)
The present experiment was conducted to determine the effects of Molasses-Urea Supplementation (MUS) on weight gain, ruminal fermentation and major microbial populations in sheep on a winter grazing regime in Inner Mongolia. Total 40 sheep, allowed free consumption of MUS after grazing, served as a treatment group, while 30 sheep, fed only by pasture grazing, served as a control group. Ruminal fermentation parameters, consisted of pH, Bacterial Crude Protein (BCP) and ammonia nitrogen (NH3-N) were measured. In addition, numbers of five symbiotic bacteria were investigated. The results showed as follows: the average daily weight gain, concentration of NH3-N and numbers of protozoa were significantly higher (p<0.05) in the treatment group than those in the control group. Contrastingly, no significant difference was found in BCP concentration and pH between the two groups. At the end of the experiment, the populations of Selenomonas ruminantium,Anaerovibrio lipolytica,Fibrobacter succinogenes,Ruminococcus flaveciens and Ruminococcus albus in the treatment group were significantly higher than those of the control group (p<0.05). These results demonstrated that greater weight gain could be induced during winter in Inner Mongolia by improved nutritional status through promotion of microbial populations using urea and sugar. 相似文献
995.
Ryuichi Nakamura Tomonari Nishimura Taehito Ochiai Satomi Nakada Mariko Nagatani Hiroyuki Ogasawara 《Journal of toxicologic pathology》2013,26(1):55-60
In rats, it is sometimes difficult to distinguish malignant reticuloses from astrocytomas in routine histopathological assessment. In the present study, four spontaneous brain neoplasms developing in the cerebrum of one Wistar Hannover rat and three Sprague-Dawley rats were immunohistochemically examined using microglia and macrophage markers. Histopathologically, these neoplasms were localized mainly in the cerebral cortex, hypothalamus or piriform lobe, and the portions showing solid growth did not show characteristic cellular arrangement but had an indistinct boundary with the surrounding brain parenchyma. Neoplastic cells had oval or pleomorphic small nuclei with abundant eosinophilic cytoplasm. Two cases showed neoplastic cell infiltration into the meninges and perivascular spaces. Silver staining showed lack of reticulin fiber production in the stroma of the neoplasms. Immunohistochemically, the neoplastic cells were strongly positive for Iba-1 and sporadically positive for CD68 in all four cases. On the basis of these results, all the neoplasms examined here could be distinguished from astrocytomas and diagnosed as malignant reticuloses. Thus, immunohistochemical demonstration of microglia/macrophage characters, such as using Iba-1, is considered to be helpful for differential diagnosis of malignant reticuloses from astrocytomas among spontaneously occurring primary brain neoplasms in rats. 相似文献
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997.
998.
Iinuma YM Suzuki M Matsuura Y Asano M Onuma M Ohtaishi N 《The Japanese journal of veterinary research》2004,51(3-4):161-166
The dental neonatal line of the sika deer (Cervus nippon) was identified experimentally using chronological labeling methods. In the enamel, prominent dark lines were observed under transmitted light, and the number of increments between the dark line and labeling line was almost consistent with the day-age at the time of labeling injection. Therefore, we identified the dark line as the enamel neonatal line. In the dentin, the bright line was observed under polarized light. Since the bright line corresponded to the enamel neonatal line, we recognized the bright line as the dentin neonatal line. Neonatal lines intersected with the enamel-dentin junction at approximately one-third cervical in the first molar. Using these features, it would make possible to distinguish the neonatal line in wild sika deer. 相似文献
999.
1000.