全文获取类型
收费全文 | 62篇 |
免费 | 4篇 |
出版年
2022年 | 1篇 |
2018年 | 1篇 |
2017年 | 2篇 |
2016年 | 1篇 |
2015年 | 2篇 |
2014年 | 1篇 |
2013年 | 1篇 |
2011年 | 1篇 |
2007年 | 1篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 5篇 |
1999年 | 2篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1987年 | 3篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1975年 | 2篇 |
1973年 | 2篇 |
1971年 | 2篇 |
1969年 | 3篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1965年 | 2篇 |
1964年 | 2篇 |
1962年 | 1篇 |
排序方式: 共有66条查询结果,搜索用时 937 毫秒
31.
Olivier Duron Florian Binetruy Valérie Noël Julie Cremaschi Karen D. McCoy Céline Arnathau Olivier Plantard John Goolsby Adalberto A. Pérez de León Dieter J. A. Heylen A. Raoul Van Oosten Yuval Gottlieb Gad Baneth Alberto A. Guglielmone Agustin Estrada‐Peña Maxwell N. Opara Lionel Zenner Fabrice Vavre Christine Chevillon 《Molecular ecology》2017,26(11):2905-2921
Ecological specialization to restricted diet niches is driven by obligate, and often maternally inherited, symbionts in many arthropod lineages. These heritable symbionts typically form evolutionarily stable associations with arthropods that can last for millions of years. Ticks were recently found to harbour such an obligate symbiont, Coxiella‐LE, that synthesizes B vitamins and cofactors not obtained in sufficient quantities from blood diet. In this study, the examination of 81 tick species shows that some Coxiella‐LE symbioses are evolutionarily stable with an ancient acquisition followed by codiversification as observed in ticks belonging to the Rhipicephalus genus. However, many other Coxiella‐LE symbioses are characterized by low evolutionary stability with frequent host shifts and extinction events. Further examination revealed the presence of nine other genera of maternally inherited bacteria in ticks. Although these nine symbionts were primarily thought to be facultative, their distribution among tick species rather suggests that at least four may have independently replaced Coxiella‐LE and likely represent alternative obligate symbionts. Phylogenetic evidence otherwise indicates that cocladogenesis is globally rare in these symbioses as most originate via horizontal transfer of an existing symbiont between unrelated tick species. As a result, the structure of these symbiont communities is not fixed and stable across the tick phylogeny. Most importantly, the symbiont communities commonly reach high levels of diversity with up to six unrelated maternally inherited bacteria coexisting within host species. We further conjecture that interactions among coexisting symbionts are pivotal drivers of community structure both among and within tick species. 相似文献
32.
33.
34.
35.
Barreiro Arcos ML Gorelik G Klecha A Genaro AM Cremaschi GA 《American journal of physiology. Cell physiology》2006,291(2):C327-C336
Regulation of cell proliferation by thyroid hormone (TH) has been demonstrated, but the effect of THs and the mechanisms involved in lymphocyte activity have not been elucidated. Differential expression of PKC isoenzymes and high nitric oxide synthase (NOS) activity have been described in tumor T lymphocytes. We have analyzed the direct actions of TH on normal T lymphocytes and BW5147 T lymphoma cells in relation to PKC and NOS activities. THs increased tumor and mitogen-induced normal T lymphocyte proliferation. PKC isoenzyme-selective blockers impaired these effects in both cell types, indicating the participation of Ca2+-dependent and -independent isoenzymes in normal and tumor cells, respectively. TH actions were blunted by extra- and intracellular Ca2+ blockers only in normal T lymphocytes, whereas NOS blockers impaired TH-induced proliferation in T lymphoma cells. Incubation for 24 h with TH induced a rise in total and membrane-associated PKC activities in both cell types and led to a rapid and transient effect only in tumor cells. THs increased atypical PKC-zeta expression in BW5147 cells and classical PKC isoenzymes in mitogen-stimulated normal T cells. TH augmented NOS activity and inducible NOS protein and gene expression only in tumor cells. Blockade of PKC and the atypical PKC-zeta isoform inhibited TH-mediated stimulation of inducible NOS and cell proliferation. These results show, for the first time, that differential intracellular signals are involved in TH modulation of lymphocyte physiology and pathophysiology. 相似文献
36.
37.
38.
Klecha AJ Salgueiro J Wald M Boccio J Zubillaga M Leonardi NM Gorelik G Cremaschi GA 《Biological trace element research》2005,104(2):173-183
Zinc and iron are crucial mineral components of human diet, because their deficiency leads to several disorders, including
alterations of the immune function. It has been demonstrated, in both humans and rodents, that a diminished number of lymphoid
cells and a loss of lymphocyte activity accompany deprivation of these essential minerals. The aim of this work was to analyze
if iron and/or zinc imbalances regulate lymphocyte activity and the intracellular signals involved in the effect. Mice from
the BALB/c strain were fed with iron- and/or zinc-deficient or mineral-supplemented diets, according to the American Institute
of Nutrition Rodent Diets. Levels of iron and zinc were assessed in blood, liver, or bone samples. Selective mitogen stimulation
of T- and B-lymphocytes were performed. We found a diminished proliferative response in T- and B-lymphocytes from zinc- and/or
iron-deficient animals with respect to controls. These effects were related to decreased mitogen-induced translocation of
protein kinase C (PKC) activity to cell membranes on both cell types from all animals fed with deficient diets. Our results
demonstrate that iron and zinc deficiencies affect both T- and B-lymphocyte function by PKC-dependent mechanisms. 相似文献
39.
Cremaschi D Porta C Bottà G Bazzini C Baroni MD Garavaglia M 《The Journal of membrane biology》2000,176(1):53-65
Cl− apically enters the epithelium of rabbit gallbladder by a Na+-Cl− symport, sensitive to hydrochlorothiazide (HCTZ). Since HCTZ also activates an apical SITS-sensitive Cl− conductance (G
Cl
), the symport inhibition might be merely due to a short circuit of the symport by G
Cl
rather than to a direct action of HCTZ on the symporter. To examine whether the symport is directly inhibited by HCTZ and
whether the symporter belongs to the family of thiazide-sensitive cotransporters (TSC), radiochemical measurements of the
apical Cl− uptake, electrophysiological determinations of intracellular Cl− and Na+ activities (a
i,Cl
and a
i,Na
) with selective theta microelectrodes and molecular biology methods were used. The 36Cl− uptake proved to be a measurement of the apical unidirectional Cl− influx (J
mc
) and of the symport only (without backflux components), with measuring times of 45 sec under all experiment conditions; its
inhibition by HCTZ was unaffected by G
Cl
activation or abolition. After HCTZ treatment the decrease in a
i,Cl
(measured as the initial rate or in 3 min) was larger than the decrease in a
i,Na
. The difference was reduced to one third in a group of epithelia in which the elicited G
Cl
was reduced to one third; moreover it was abolished in any case when G
Cl
was abolished with 10−4
m SITS. The SITS-insensitive rate of a
i,Cl
decrease was equal to that of the a
i,Na
decrease in any case. Thus the a
i,Cl
decrease displays a component dependent on G
Cl
activation and a second component dependent on symport inhibition. Using the RT-PCR technique a cDNA fragment was obtained
that was 99% identical to the corresponding region of the rabbit renal TSC isoform. The results indicate that in rabbit gallbladder
epithelium HCTZ displays a dual action, namely G
Cl
activation and Na+-Cl− symport inhibition. This Na+-Cl− symporter is the first TSC found to be functionally expressed in a nonrenal or nonrenal-like epithelium.
Received: 29 July 1999/Revised: 23 March 2000 相似文献
40.
Sterin-Borda Leonor Cremaschi Graciela Genaro Ana Maria Echagüe Agustina Vila Goin Juan Carlos Borda Enri 《Molecular and cellular biochemistry》1996,162(1):75-82
We have already demonstrated the presence of antibodies in the sera of chagasic patients with the ability to interact with neurotransmitter receptors triggering several intracellular pathways of transduction signals. Here we show that, chagasic IgG induced protein kinase C (PKC) translocation to rat cardiac membranes and this effect was inhibited by muscarinic cholinergic blockers atropine and AF-DX 116 pointing to the participation of M2 receptors in this effect. It was also able to stimulate nitric oxide synthase (NOS) activity and this action was blunted by phospholipase C (PLC) and PKC inhibitors indicating that the production of nitric oxide (NO) would be the consequence of the cascade of enzymatic pathways triggered by mAChR activation. PKC and NOS activities were involved in chagasic IgG negative inotropic actions on rat isolated myocardium as its effects were blunted by staurosporine and L-N-monomethyl arginine. Furthermore, low concentrations of chagasic IgG inhibited the cardiac mechanical action of carbachol in a non-competitive manner. These data suggested that PKC activation in myocardium by chagasic IgG would be involved in its physiological actions by modulating NOS activity. The participation of PKC-mediated phosphorylation of mAChR leading to receptor desensitization as one of the causes of dysautonomia is also discussed. 相似文献