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2.
M S Oba E de B Mello A Dell'Porto M A Soares T T Schumaker 《Arquivos do Instituto Biológico》1979,46(3-4):127-130
The phosphate sale of tetramizol assayed in naturally infested sheep by subcutaneous infection at the dosis of 8,66 mg/kg revealed very high efficiency against strongylid gastro-intestinal nematodes; its efficiency was comparable that found by several authors for the hydrochloride and cyclamate salts of the same drug, also by subcutaneious injection, at the dosis of 10 mg/kg. In what concerns helminths belonging to the genera Strongyloides and Capillaria our results were not conclusive enough. 相似文献
3.
Jørn Stave Gufu Oba Inger Nordal Nils Chr Stenseth 《Biodiversity and Conservation》2007,16(5):1471-1489
The present study explores traditional ecological knowledge (TEK) of Turkana pastoralists and cultivators in the context of
a riverine forest in northern Kenya. The Turkwel River and its floodplain sustain a thick forest, which is used for grazing
and extraction of non-timber forest products. However, sedentarisation and agricultural expansion have resulted in localised
clear-felling of trees, while river damming has altered the natural flow regime. A series of structured, semi-structured,
and group interviews were combined with a botanical inventory in order to assess the relevance of TEK to ecological research
and forest conservation. Turkana informants gave 102 vernacular names for the 113 woody species. Of these, 85% had a domestic
or pastoral use among the 105 specific uses that were described. Ethnobotanical knowledge was relatively homogenous and not
related to age, gender, or source of livelihood. The informants had in-depth knowledge of some key ecological processes. The
conceived threats to forest survival were primarily cultivation and permanent settlements, while the effects of river damming
and livestock grazing were disputed. A claimed decline in rainfall was confirmed by official data. There is strong evidence
that TEK could be used to generate hypotheses for research and to design sustainable conservation strategies. A revised version
of the indigenous system of tree management should be incorporated into the official forestry policy in order to resolve future
conflicts between pastoralists and cultivators. 相似文献
4.
Takahashi M Suzuki E Takeda R Oba S Nishimatsu H Kimura K Nagano T Nagai R Hirata Y 《American journal of physiology. Heart and circulatory physiology》2008,294(6):H2879-H2888
We examined whether ANG II and TNF-alpha cooperatively induce vascular inflammation using the expression of monocyte chemoattractant protein (MCP)-1 as a marker of vascular inflammation. ANG II and TNF-alpha stimulated MCP-1 expression in a synergistic manner in vascular smooth muscle cells. ANG II-induced MCP-1 expression was potently inhibited to a nonstimulated basal level by blockade of the p38-dependent pathway but only partially inhibited by blockade of the NF-kappaB-dependent pathway. In contrast, TNF-alpha-induced MCP-1 expression was potently suppressed by blockade of NF-kappaB activation but only modestly suppressed by blockade of p38 activation. ANG II- and TNF-alpha-induced activation of NF-kappaB- and p38-dependent pathways was partially inhibited by pharmacological inhibitors of ROS production. Furthermore, ANG II- and TNF-alpha-stimulated MCP-1 expression was partially suppressed by ROS inhibitors. We also examined whether endogenous ANG II and TNF-alpha cooperatively promote vascular inflammation in vivo using a wire injury model of the rat femoral artery. Blockade of both ANG II and TNF-alpha further suppressed neointimal formation, macrophage infiltration, and MCP-1 expression in an additive manner compared with blockade of ANG II or TNF-alpha alone. These results suggested that ANG II and TNF-alpha synergistically stimulate MCP-1 expression via the utilization of distinct intracellular signaling pathways (p38- and NFkappaB-dependent pathways) and that these pathways are activated in ROS-dependent and -independent manners. These results also suggest that ANG II and TNF-alpha cooperatively stimulate vascular inflammation in vivo as well as in vitro. 相似文献
5.
Kiyotaka Chinzei Kantaro Fujioka Hiroshi Kitazato Itaru Koizumi Tadamichi Oba Motoyoshi Oda Hisatake Okada Toyosaburo Sakai Yoshihiro Tanimura 《Marine Micropaleontology》1987,11(4)
Downcore changes in microfossil assemblages and oxygen isotope ratios in three piston cores recovered from the Northwestern Pacific, off central Japan, show that the subtropical Kuroshio front was located to the south of C-4 core site (Lat. 33° N) during the last glacial. The front then advanced northward, passing over the C-4 site and the C-6 site (34.6° N) at about 13 ka and 10 ka, respectively, and reached the C-1 core site (36° N) at about 7 ka. After 5.5 ka it retreated to the area between the C-1 and C-6 sites. A brief but significant cold event, the readvance of the cold Oyashio Current, is recognized between 11 and 10 ka in the two northern cores, but the current did not reach the southern C-4 site. A contemporaneous cold event is known in the North Atlantic, and the cooling was probably a global phenomenon likely to be associated with lowering of sea level. Contamination of isotopically light water is apparent between 14 and 11 ka in the marked change in isotopic composition of benthic foraminifers. Oxygen isotope ratios of planktonic foraminifers show that prior to the advance of the Kuroshio front, the surface water at these core sites was isotopically lighter than the Kuroshio water at that time. 相似文献
6.
Yuko Ishizaki Mitsue Maru Hirohiko Higashino Shoko Katsumoto Kyoko Egawa Yoshitoki Yanagimoto Teruyo Nagahama 《BioPsychoSocial medicine》2012,6(1):1-4
Background
Advances in medical science have enabled many children with chronic diseases to survive to adulthood. The transition of adult patients with childhood-onset chronic diseases from pediatric to adult healthcare systems has received attention in Europe and the United States. We conducted a questionnaire survey among 41 pediatricians at pediatric hospitals and 24 nurses specializing in adolescent care to compare the perception of transition of care from pediatric to adult healthcare services for such patients.Findings
Three-fourths of the pediatricians and all of the nurses reported that transition programs were necessary. A higher proportion of the nurses realized the necessity of transition and had already developed such programs. Both pediatricians and nurses reported that a network covering the transition from pediatric to adult healthcare services has not been established to date.Conclusions
It has been suggested that spreading the importance of a transition program among pediatricians and developing a pediatric-adult healthcare network would contribute to the biopsychosocial well-being of adult patients with childhood-onset chronic disease. 相似文献7.
8.
9.
Histological studies on male sterility of hybrids between laboratory and wild mouse strains 总被引:1,自引:0,他引:1
Atsushi Yoshiki Kazuo Moriwaki Teruyo Sakakura Moriaki Kusakabe 《Development, growth & differentiation》1993,35(3):271-281
In this study the cellular mechanisms of male sterility in F1 hybrids (BNF1) between BALB/c and wild-derived M.MUS-NJL (NJL) was investigated. Cell proliferation and differentiation in the sterile testis were examined by bromodeoxyuridine-labeling and use of germ cell stage-specific antibodies. In BNF1 testes, spermatogonia actively proliferated with a seminiferous epithelial cycle, and were retained in the basal layer of the tubules. However, preleptotene, leptotene and zygotene spermatocytes moved to the adluminal region. Immunohistological data with germ cell stage-specific antibodies indicated the presence of few, if any, pachytene spermatocytes in BNF1 testes. Thus, spermatogenesis seemed to be blocked at the zygotene stage. For examination of germ cell-Sertoli cell interactions, testes of aggregation chimeras between BNF1 and C3H/HeN were analyzed immunohistologically with C3H-specific antibody. Results showed that spermatogenesis of C3H-germ cells was normal, even when these cells in contact with BNF1-Sertoli cells. Differentiation of BNF1-germ cells progressed from zygotene to pachytene stage spermatocytes when these cells were surrounded by C3H-Sertoli cells, but never proceeded beyond the pachytene stage. These observations suggest that at least two different cellular factors may be involved in spermatogenesis, one acting in the germ cells and the other mediated by Sertoli cells. Furthermore, mating experiments revealed that the degree of spermatogenesis varied in different F1 hybrids, and that the major sterility factor was closely linked to the T -locus on chromosome 17. 相似文献
10.
Hiroki Murakami Ruri Katsunuma Kentaro Oba Yuri Terasawa Yuki Motomura Kazuo Mishima Yoshiya Moriguchi 《PloS one》2015,10(6)
Mindfulness, an attentive non-judgmental focus on “here and now” experiences, has been incorporated into various cognitive behavioral therapy approaches and beneficial effects have been demonstrated. Recently, mindfulness has also been identified as a potentially effective emotion regulation strategy. On the other hand, emotion suppression, which refers to trying to avoid or escape from experiencing and being aware of one’s own emotions, has been identified as a potentially maladaptive strategy. Previous studies suggest that both strategies can decrease affective responses to emotional stimuli. They would, however, be expected to provide regulation through different top-down modulation systems. The present study was aimed at elucidating the different neural systems underlying emotion regulation via mindfulness and emotion suppression approaches. Twenty-one healthy participants used the two types of strategy in response to emotional visual stimuli while functional magnetic resonance imaging was conducted. Both strategies attenuated amygdala responses to emotional triggers, but the pathways to regulation differed across the two. A mindful approach appears to regulate amygdala functioning via functional connectivity from the medial prefrontal cortex, while suppression uses connectivity with other regions, including the dorsolateral prefrontal cortex. Thus, the two types of emotion regulation recruit different top-down modulation processes localized at prefrontal areas. These different pathways are discussed. 相似文献