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The effects of food availability and ambient temperature (Ta) on hibernation in the Japanese dormouse,Glirulus japonicus, were examined. When the dormice were deprived of food under natural environmental conditions in midwinter, they showed typical
hibernation patterns; in contrast, the animals given ad lib food did not show continuous long-term torpor. Furthermore, exposure
to constant low temperature did not affect the torpor patterns in the animals receiving adequate food. These results suggest
that food availability plays a decisive role in the onset and maintenance of hibernation in this species, and that low Ta
does not have a great influence on the torpor patterns in animals with access to food. This differs from the previous study
that emphasized the importance of Ta in the occurrence of torpor and discounted the effects of food shortage. 相似文献
3.
T Nimura M Okada M Shimizu M Kawabe T Itoh M Iwasaki H Kimura T Takeuchi 《The Annals of physiological anthropology》1990,9(4):329-333
Motorcyclists who work in some offices sometimes complained of coldness, pain and numbness of upper limbs. We studied how to discriminate between vibration syndrome and local fatigue of the motorcyclists. Subjects are 42 motorcyclists of an office in Aichi prefecture. 25 of them held several letters in their left hand when they delivered the letters. They complained of coldness, pain and numbness in the left upper limbs more than in the right limbs (p less than 0.01). We think that it is the local fatigue rather than the disorder of vibration syndrome that causes such symptoms. So it is very important to recognize the existence of local fatigue in order to know how to discriminate between vibration syndrome and local fatigue of the motorcyclists. 相似文献
4.
Takahiro Watanabe Yohei Narita Masahiro Yoshida Yoshitaka Sato Fumi Goshima Hiroshi Kimura Takayuki Murata 《Journal of virology》2015,89(19):10120-10124
Epstein-Barr virus (EBV) is a gammaherpesvirus, associated with infectious mononucleosis and various types of malignancy. We focused here on the BDLF4 gene of EBV and identified it as a lytic gene, expressed with early kinetics. Viral late gene expression of the BDLF4 knockout strain was severely restricted; this could be restored by an exogenous supply of BDLF4. These results indicate that BDLF4 is important for the EBV lytic replication cycle, especially in late gene expression. 相似文献
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Received 20 September 2001/ Accepted in revised form 10 October 2001 相似文献
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Takeshi Kawamura Noriyuki Kuroda Yuko Kimura Eliada Lazoura Noriko Okada Hidechika Okada 《Biochemical genetics》2001,39(1-2):33-42
We examined embryonic carcinoma (EC) cells for a potential prototype molecule of C3, the third component of complement. PCR primers, corresponding to the base sequence derived from the C3 cDNA of several species, were used for PCR amplification of the EC cell cDNA. All the PCR products obtained had the same sequence and showed no sequence homology to C3. Subsequently, cDNA clones were isolated from a mouse liver cDNA library using the PCR product as a probe. Unexpectedly, neither the base sequence of the cDNA clones nor the amino acid sequence deduced from the cDNA showed homology to C3, although partial homology was observed to a number of sequences from EST databases. We designated this new clone NCU-G1. Northern hybridization experiments revealed that NCU-G1 is expressed constitutively not only in the mouse fetus but also in various mouse tissues, and is most abundant in the kidney cortex. 相似文献
10.
Effect of sodium butyrate on actin distribution in rat 3Y1 fibroblasts in monolayer culture 总被引:1,自引:0,他引:1
We studied the effect of sodium butyrate, a potent G1/G2-arresting agent, on actin distribution in rat 3Y1 fibroblasts in monolayer culture by fluorescence microscopy of cells stained with 7-nitrobenz-2-oxa-1, 3-diazole phallacidine (NBD-Ph). When randomly proliferating cells were arrested mainly in G1 phase with butyrate, a reversible overaccumulation of cellular net protein occurred. In the G1-arrested cells, actin markedly accumulated at the margin of cells, and a network structure of actin stress fibers appeared. When density-arrested cells were replated sparsely and rearrested in the G1, early S, and G2 phases with butyrate or hydroxyurea, the actin network was observed extensively in the cells arrested in the G1 and G2 phases with butyrate. These results agree with our previous results indicating the existence of some physiological similarity between cells in the G1 and G2 phases and suggest that actin distribution somehow depends on the phases of the cell cycle. The actin profiles observed by the NBD-Ph staining were confirmed by transmission electronmicroscopy (TEM) of negatively stained whole cells. TEM further revealed that electron-dense amorphous materials were present at crossing points in the network but rarely present on interconnecting microfilament bundles. 相似文献