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排序方式: 共有158条查询结果,搜索用时 62 毫秒
91.
Lidia Osuna María Esther Tapia-Pérez Odette Figueroa Enrique Jiménez-Ferrer María Luisa Garduño-Ramírez María Teresa González-Garza Pilar Carranza-Rosales Delia Elva Cruz-Vega 《In vitro cellular & developmental biology. Plant》2006,42(6):596-600
Summary Micropropagation is a technique to ensure a constant and uniform source of medicinal plants. In this report, we describe the
micropropagation of Lepidium virginicum L. (Brassicaceae), a wild plant used as an antiamoebic in traditional Mexican medicine. In vitro-germinated seeds were cultured in Murashige and Skoog (MS) medium to obtain pathogen-free cotyledons, hypocotyls, and apical
bud (AB) explants. For induction of morphogenesis, the effect of cytokinins, benzyladenine (BA) and kinetin (KN), combined
with auxin, indole-3-acetic acid (IAA) was evaluated. The best rate of shoot proliferation was induced 15 d after culture
on MS mineral medium supplemented with IAA∶KN (0.57∶13.94 μM) from AB explants. Maximum shoot elongation was achieved without plant growth regulators. The effect of indole-3-butyric
acid (IBA) (14.76 μM) was evaluated for in vitro root induction; 60 d after culture all the shoots had developed roots. All rooted plants were successfully transferred to
pots and 100% acclimatized in ex vitro conditions. The methanol extracts from the micropropagated active explants of L. virginicum showed and IC50 antiprotozoal value between 141.90 and 268.53 μg ml−1. 相似文献
92.
Aboriginal economic relations have been misconstrued as a type of primitive exchange in at least one native title case discussed in this paper. The pursuit by Aboriginal native title claimants of recognition at law of customary economic rights as inherent in, or an adjunct of, native title rights failed in Yarmirr and Others v. Northern Territory of Australia and Others (1998) 156 ALR 370 (the ‘Croker Island case’) for several reasons. The applicant's native title was found to be non‐exclusive of other interests, and a right to trade in resources of the sea was rejected. This case was argued in part by relying on historical material regarding Macassan trading arrangements. The profound alterity of Aboriginal relationships among persons and things, as the Croker Island evidence of property and trade relations demonstrates, have been re‐constituted in legal discourse as an absence of economic relations. In this paper, we argue that there is no sound basis for the distinction made between commercial and non‐commercial native title rights, whether in the Native Title Act 1993 (Commonwealth of Australia), or in recent judicial reasoning. We contend that native title rights and interests constitute a sui generis species of property relations that enable economic rights as conceived in Aboriginal tradition and custom to circulate in the modern market. Aboriginal customary economic relations of and between Aboriginal groupings are markedly distinct from, yet not incommensurable with, the normative conception of economic relations in the Australian market. We argue that a reformulation of the current Australian legal ideas about economic life is necessary for the recognition of Aboriginal economic institutions in native title claims and other economic arenas. 相似文献
93.
94.
Bruno Delobel Ratib Djlelati Odette Gabriel-Robez Marie-Françoise Croquette Roselyne Rousseaux-Prévost Jean Rousseaux Jean-Marc Rigot Y. Rumpler 《Human genetics》1998,102(1):98-102
An apparently balanced reciprocal translocation 46,X,t(Y;6) (q11.23 ∼ q12;p11.1) was observed in an infertile man with severe
oligozooteratozoospermia. Different mitotic chromosome banding patterns were performed and fluorescence in situ hybridization
indicated a breakpoint in the fluorescent Yq heterochromatin. Molecular genetic deletion experiments for the azoospermia factor
region in distal Yq11 showed the retention of the DAZ gene and meiotic pairing configurations suggested that the man’s infertility
could be due to the pairing behaviour of the Y;6 translocation chromosome with the X chromosome visualised by synaptonemal
complex analysis at the electron microscopy level. The morphological appearance of the normal chromosome 6 and the Y;6 translocated
chromosome included in the compartment of the sex vesicle may allow an explanation of the degeneration of most spermatocytes
after the pachytene stage.
Received: 1 August 1997 / Accepted: 25 September 1997 相似文献
95.
96.
Ochratoxin A was detected as a natural contaminant for the first time. It was present in a corn sample. 相似文献
97.
Rupert W. Overall Tara L. Walker Odette Leiter Sina Lenke Susann Ruhwald Gerd Kempermann 《PloS one》2013,8(12)
This study builds on the findings that physical activity, such as wheel running in mice, enhances cell proliferation and neurogenesis in the adult hippocampus of the common mouse strain C57BL/6, and that the baseline level of neurogenesis varies by strain, being considerably lower in DBA/2. Because C57BL/6 and DBA/2 are important as the parental strains of the BXD recombinant inbred cross which allows the detection of genetic loci regulating phenotypes such as adult neurogenesis, we performed the current study to investigate the gene x environment interactions regulating neurogenesis. At equal distances and times run DBA/2J mice lacked the acute increase in precursor cell proliferation known from C57BL/6. In DBA/2J proliferation even negatively correlated with the distance run. This was neither due to a stress response (to running itself or single housing) nor differences in estrous cycle. DBA/2 animals exhibited a delayed and weaker pro-neurogenic response with a significant increase in numbers of proliferating cells first detectable after more than a week of wheel running. The proliferative response to running was transient in both strains, the effect being undetectable by 6 weeks. There was also a small transient increase in the production of new neurons in DBA/2J, although these extra cells did not survive. These findings indicate that the comparison between C57BL/6 and DBA/2, and by extension the BXD genetic reference population derived from these strains, should provide a powerful tool for uncovering the complex network of modifier genes affecting the activity-dependent regulation of adult hippocampal neurogenesis. More generally, our findings also describe how the external physical environment interacts with the internal genetic environment to produce different responses to the same behavioral stimuli. 相似文献
98.
Long HM Leese AM Chagoury OL Connerty SR Quarcoopome J Quinn LL Shannon-Lowe C Rickinson AB 《Journal of immunology (Baltimore, Md. : 1950)》2011,187(1):92-101
EBV, a B lymphotropic herpesvirus, encodes two immediate early (IE)-, >30 early (E)-, and >30 late (L)-phase proteins during its replication (lytic) cycle. Despite this, lytic Ag-induced CD8 responses are strongly skewed toward IE and a few E proteins only, all expressed before HLA I presentation is blocked in lytically infected cells. For comparison, we examined CD4(+) T cell responses to eight IE, E, or L proteins, screening 14 virus-immune donors to overlapping peptide pools in IFN-γ ELISPOT assays, and established CD4(+) T cell clones against 12 defined epitopes for target-recognition assays. We found that the lytic Ag-specific CD4(+) T cell response differs radically from its CD8 counterpart in that it is widely distributed across IE, E, and L Ag targets, often with multiple reactivities detectable per donor and with IE, E, or L epitope responses being numerically dominant, and that all CD4(+) T cell clones, whether IE, E, or L epitope-specific, show strong recognition of EBV-transformed B cell lines, despite the lines containing only a small fraction of lytically infected cells. Efficient recognition occurs because lytic Ags are released into the culture and are acquired and processed by neighboring latently infected cells. These findings suggested that lytic Ag-specific CD4 responses are driven by a different route of Ag display than drives CD8 responses and that such CD4 effectors could be therapeutically useful against EBV-driven lymphoproliferative disease lesions, which contain similarly small fractions of EBV-transformed cells entering the lytic cycle. 相似文献
99.
Plant diversity shapes microbe‐rhizosphere effects on P mobilisation from organic matter in soil
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Nina Hacker Anne Ebeling Arthur Gessler Gerd Gleixner Odette González Macé Hans de Kroon Markus Lange Liesje Mommer Nico Eisenhauer Janneke Ravenek Stefan Scheu Alexandra Weigelt Cameron Wagg Wolfgang Wilcke Yvonne Oelmann 《Ecology letters》2015,18(12):1356-1365
Plant species richness (PSR) increases nutrient uptake which depletes bioavailable nutrient pools in soil. No such relationship between plant uptake and availability in soil was found for phosphorus (P). We explored PSR effects on P mobilisation [phosphatase activity (PA)] in soil. PA increased with PSR. The positive PSR effect was not solely due to an increase in Corg concentrations because PSR remained significant if related to PA:Corg. An increase in PA per unit Corg increases the probability of the temporal and spatial match between substrate, enzyme and microorganism potentially serving as an adaption to competition. Carbon use efficiency of microorganisms (Cmic:Corg) increased with increasing PSR while enzyme exudation efficiency (PA:Cmic) remained constant. These findings suggest the need for efficient C rather than P cycling underlying the relationship between PSR and PA. Our results indicate that the coupling between C and P cycling in soil becomes tighter with increasing PSR. 相似文献
100.
Niels Hammer Robert M?bius Stefan Schleifenbaum Karl-Heinz Hammer Stefan Klima Justin S. Lange Odette Soisson Dirk Winkler Thomas L. Milani 《PloS one》2015,10(8)