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1.
Alvarez, J. and Guerra, H. 1985. Biochemical and morphologicalchanges in protein bodies during germination of lentil seeds.—J.exp. BoL 36: 1296–1303. Protein bodies were extracted from lentil (Lens culinaris Medilk,var. castellana) seeds. Proteins from the protein bodies weredegraded during the first 7 d of germination. In some casesthis mobilization of proteins was accompanied by fusion of theprotein bodies into a large central vacuole. The loss of proteinswas paralleled by an increase in the activity of an enzyme systemthat hydrolysed casein. The different kinds of protein bodiesexhibited structural differences; some displayed uniform material,others coagulated or semi-coagulated material and the thirdkind displayed inclusions. Key words: Lentil, protein bodies, seed germination  相似文献   
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ABSTRACT. Entamoeba histolytica causes amebic dysentery (AD) and liver abscess (ALA). Little is known about protective immunity to amebiasis, and studies in this area have been complicated by the paucity of defined ameba antigens. We examined the proliferative responses of peripheral blood mononuclear cells (PBMC) from patients with AD and ALA to a recombinant protein containing a portion of the 170 kDa adhesin of E. histolytica (170CR), and to two synthetic peptides (1 and 2) derived from the 170 kDa sequence that were predicted to contain T cell epitopes. A significant number of patients with AD and ALA had PBMC that proliferated to 170CR molecule, and several individuals with ALA and AD had T cells that recognized one or both peptides. Contrarily, individuals from a non-endemic region for amebiasis did not respond to 170CR protein, or to both peptides. In regard to antibody response, nine of fifteen patients with ALA showed antibodies to 170CR protein. These same patients had antibodies to peptide 2. We identified peptides from 170-kDa adhesin that may contain both T and B cell epitopes recognized by some patients with invasive amebiasis. These peptides may be valuable reagents in studies of the immune response to amebiasis.  相似文献   
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The influence of the pineal gland on the hypothalamic serotonergic function was examined by studying the effects of long-term pinealectomy (1 month) and melatonin replacement (500 μg/kg; 10 days) on serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) content as well as on the in vivo 5-HT synthesis rate in discrete hypothalamic nuclei. Pinealectomy was followed by a significant decrease of 5-HT content in the anterior hypothalamic nuclei (AHN) and the ventromedial hypothalamic nuclei (VMHN), and also in 5-HIAA content in lateral (LPON) and medial preoptic nuclei (MPON). The 5-HT synthesis rate, estimated from the accumulation of 5-hydroxytryptophan after blockade of the 1-amino acid decarboxylase activity, were also decreased in the AHN and the paraventricular hypothalamic nuclei (PVHN) of pinealectomized rats. In contrast, an enhanced 5-HT synthesis rate and basal 5-HIAA content were found in the suprachiasmatic nuclei (SCN) after pinealectomy. Daily treatment with melatonin for 10 days reversed most of the effects induced by pinealectomy. Thus, melatonin increased the levels of 5-HT in the AHN and VMHN, and slightly increased the 5-HIAA content in preoptic nuclei. In addition, melatonin increased the 5-HT synthesis rate in the AHN and VMHN, but also in the MPON, VMHN and dorsomedial hypothalamic nuclei (DMHN) where pinealectomy had no effect. By contrast, melatonin treatment did not affect SCN 5-HT synthesis rate, although it decreased 5-HIAA levels. The results demonstrate that melatonin is able to stimulate 5-HT metabolism in most of the hypothalamic areas, but inhibits SCN 5-HT function. Some of the effects of melatonin seems to be exerted by modulating the synthesis of the amine, although melatonin likely also interacts with other regulatory processes of 5-HT function (i.e. release/uptake). The well defined presence of melatonin receptors in the rat SCN, and its absence in other hypothalamic structures, suggest that this may be the mechanism mediating the differential response to endogenous melatonin. Moreover, the larger effect of exogenous melatonin in relation to pinealectomy suggests the presence of melatonin unespecific effects possibly owing to supraphysiological doses. The present findings may be relevant for the mode of action of melatonin and its implication in several endocrine and behavioral functions mediated by serotonergic neurons. Copyright © 1996 Elsevier Science Ltd  相似文献   
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The goal of the present study was to obtain valuable microsatellite markers useful in genetic approaches of the shrimp Litopenaeus vannamei, an important aquaculture species of the world. Eight loci produced suitable polymorphic patterns with allele number ranging from two to 12 and expected heterozygosity from 0.18 to 0.89. Cross‐species amplification was successfully performed in five other penaeid species (Litopenaeus schmitti, Farfantepenaeus brasiliensis, Farfantepenaeus paulensis, Xiphopenaeus kroyeri and Rimapenaeus constrictus), indicating that some these loci can be useful in studies of other related species.  相似文献   
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There is a marked underepresentation of low- and middle-income countries (LAMIC) in the psychiatric literature, which may reflect an overall low representation of LAMIC publications in databases of indexed journals. This paper investigates the worldwide distribution of indexed psychiatric journals. A survey in both Medline and ISI Web of Science was performed in order to identify journals in the field of psychiatry according to their country of origin. Two hundred and twenty-two indexed psychiatric journals were found. Of these, 213 originated from high-income countries and only nine (4.1%) from middle-income countries. None were found in low-income countries. We also present the experience of a LAMIC psychiatric journal, the Revista Brasileira de Psiquiatria, in its recent indexation process. This case study may serve as an example for other LAMIC journals to pursue indexation in major databases as a strategy to widen the international foundation of psychiatric research. There is an important need for the inclusion of LAMIC psychiatric publications in the major indexation databases. This process will require multiple agents to partner with journals from LAMIC to improve their quality and strengthen their chances of being indexed.  相似文献   
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The western Mediterranean geophyte Anemone palmata L. is one of the most endangered angiosperm taxa in France. The biological and ecological characteristics of French populations are contrasted with those of populations from near the centre of the species distribution in east Spain. A Correspondence Analysis discriminates the French and Spanish populations according to substrate and the composition of the plant communities where they grow. The karyological study reveals that east Spanish plants are autotetraploid, whilst the French are all diploid. In addition, morphological differences were registered, Spanish plants generally being more vigorous. French populations consist mostly of senile plants, without or with very low rates of sexual reproduction, whereas the populations from Spain include all age groups with an important percentage of juvenile plants. The main factors which could affect the French populations are habitat destruction and modification of plant communities due to land-abandonment. Conservation measures should be supported by immediate protection of the French localities and habitats to prevent the total decline of this rare species.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 95–114.  相似文献   
9.
Seed dormancy in relation to seed storage behaviour in Acer   总被引:3,自引:0,他引:3  
Dormancy in seeds of Acer opalus is shown to be mainly caused by the seed coats, although a slight embryo dormancy exists in fresh seeds. The ability to germinate after drying indicates that seed storage behaviour is orthodox. Recalcitrant seeds were heavier than orthodox seeds not only within section Acer but also within the whole genus after statistical control of phylogeny, through a phylogenetic ANOVA with data from two different Acer phylogenies. An evolutionary change from orthodox to recalcitrant behaviour is postulated for genus Acer , but this change appears not to have been accompanied by a change in seed dormancy, at least in the taxonomic section in which Acer opalus belongs.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 145 , 203–208.  相似文献   
10.
New information on Aegires ortizi Templado, Luque & Ortea,1987 is given, and two new species of the genus Aegires aredescribed, one from the Caribbean and one from the MediterraneanSea. A key to the North Atlantic species of Aegires is given. (Received 10 February 1989; accepted 11 July 1989)  相似文献   
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