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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
3.
Keisuke Takata Masaharu Hoshino Wichian Magtoon Nivesh Nadee Hiroshi Uwa 《Ichthyological Research》1993,39(4):319-327
An allozyme survey was conducted in eleven local populations ofOryzias minutillus from Thailand. The region-specific distribution of alleles and the genetic relationship among the eleven populations revealed that they represented major three population groups, within the country as a whole; the Peninsular, Mae Nam Chao Phraya and Mekong subpopulations. Because their distribution boundaries coincide with geographic features, it is supposed that their genetic differentiation is primarily due to geographic isolation. Karyotype polymorphism has been reported only from the Mae Nam Chao Phraya subpopulation, suggesting that the variant karyotype evolved after allopatric isolation of the three subpopulations. 相似文献
4.
Sumiko Hara Chisato Kaneko Hiroatsu Matsumoto Takeshi Nishino Tadao Takeuchi Takeo Mori 《Nucleosides, nucleotides & nucleic acids》2013,32(2-4):571-582
Abstract Novel β-D-ribofuranosides having a 5-substituted imidazo [4,5-d] [1,3]thiazine ring, including the S6-congener 3 of oxanosine 2, were synthesized for screening their anticancer and antiviral activities. 相似文献
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A melanoma cell clone was isolated from cultured B16 mouse melanoma cells. This clone, conv, which was characterized by rounded and spindle-shaped cell morphology, was not highly melanotic under the usual culture condition but had high tyrosinase (dopa oxidase) activity. When the cells were seeded to form colonies on a plastic culture dish in Eagle's minimum essential medium supplemented with 10% bovine calf serum, two kinds of cell types always appeared. One was cytochemically dopa-positive and spindle-shaped (S type cell) with the same phenotypes as those of the parental cells. The other was dopa-negative and fibroblastlike (F type cell) containing no melanosomes. It was observed that the conversion from S type to F type occurred with a high frequency. The conversion from F type to S type also occurred but with a low frequency. 相似文献
7.
The reactions of 2'-O- or 3'-O-tosylated adenosines with Grignard reagents resulted in the formation of various products, which were deoxy or branched-chain deoxy sugar nucleosides, 1',2'-unsaturated nucleosides, 3'-deoxy-2'-keto sugar nucleosides, and so on. The convenient method for the synthesis of the 3'-deoxy-2'-keto adenine nucleoside is described. 相似文献
8.
Undifferentiated embryonal carcinoma cells (EC cells) in the embryoid bodies isolated from mouse teratocarcinoma contained nucleolus-like bodies (NLBs) of smaller sizes in their cytoplasm (their sectional area averaged about 0.036 μm2). At the onset of EC cell differentiation, the average sectional area of NLBs significantly increased (about 0.107 μm2). When EC cells had differentiated into mesenchymal cells and endothelial cells of primitive blood vessels, NLBs decreased dramatically both in size and number. The possible role of NLBs in the differentiation process of EC cells is discussed. 相似文献
9.
Tomonori Ueno Keisuke Tanaka Keiko Kaneko Yuki Taga Tetsutaro Sata Shinkichi Irie Shunji Hattori Kiyoko Ogawa-Goto 《The Journal of biological chemistry》2010,285(39):29941-29950
A coiled-coil microtubule-bundling protein, p180, was originally reported as a ribosome-binding protein on the rough endoplasmic reticulum (ER) and is highly expressed in secretory tissues. Recently, we reported a novel role for p180 in the trans-Golgi network (TGN) expansion following stimulated collagen secretion. Here, we show that p180 plays a key role in procollagen biosynthesis and secretion in diploid fibroblasts. Depletion of p180 caused marked reductions of secreted collagens without significant loss of the ER membrane or mRNA. Metabolic labeling experiments revealed that the procollagen biosynthetic activity was markedly affected following p180 depletion. Moreover, loss of p180 perturbs ascorbate-stimulated de novo biosynthesis mainly in the membrane fraction with a preferential secretion defect of large proteins. At the EM level, one of the most prominent morphological features of p180-depleted cells was insufficient ribosome association on the ER membranes. In contrast, the ER of control cells was studded with numerous ribosomes, which were further enhanced by ascorbate. Similarly biochemical analysis confirmed that levels of membrane-bound ribosomes were altered in a p180-dependent manner. Taken together, our data suggest that p180 plays crucial roles in enhancing collagen biosynthesis at the entry site of the secretory compartments by a novel mechanism that mainly involves facilitating ribosome association on the ER. 相似文献
10.
Aiko Shinko Takashi Agari Masahiro Kameda Takao Yasuhara Akihiko Kondo Judith Thomas Tayra Kenichiro Sato Tatsuya Sasaki Susumu Sasada Hayato Takeuchi Takaaki Wakamori Cesario V. Borlongan Isao Date 《PloS one》2014,9(7)
In clinical practice, deep brain stimulation (DBS) is effective for treatment of motor symptoms in Parkinson’s disease (PD). However, the mechanisms have not been understood completely. There are some reports that electrical stimulation exerts neuroprotective effects on the central nervous system diseases including cerebral ischemia, head trauma, epilepsy and PD, although there are a few reports on neuroprotective effects of spinal cord stimulation (SCS). We investigated the neuroprotective effects of high cervical SCS on PD model of rats. Adult female Sprague-Dawley rats received hour-long SCS (2, 50 or 200 Hz) with an epidural electrode at C1–2 level for 16 consecutive days. At 2 days after initial SCS, 6-hydroxydopamine (6-OHDA) was injected into the right striatum of rats. Behavioral evaluations of PD symptoms were employed, including cylinder test and amphetamine-induced rotation test performed at 1 and 2 weeks after 6-OHDA injection. Animals were subsequently euthanized for immunohistochemical investigations. In order to explore neurotrophic and growth factor upregulation induced by SCS, another cohort of rats that received 50 Hz SCS was euthanized at 1 and 2 weeks after lesion for protein assays. Behavioral tests revealed that the number of amphetamine-induced rotations decreased in SCS groups. Immunohistochemically, tyrosine hydroxylase (TH)-positive fibers in the striatum were significantly preserved in SCS groups. TH-positive neurons in the substantia nigra pars compacta were significantly preserved in 50 Hz SCS group. The level of vascular endothelial growth factor (VEGF) was upregulated by SCS at 1 week after the lesion. These results suggest that high cervical SCS exerts neuroprotection in PD model of rats, at least partially by upregulation of VEGF. SCS is supposed to suppress or delay PD progression and might become a less invasive option for PD patients, although further preclinical and clinical investigations are needed to confirm the effectiveness and safety. 相似文献