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1.
Cornel Schmitt und Hans Stadler 《Journal of Ornithology》1918,66(2):220-234
Ohne ZusammenfassungIII.) Nachtigall, Kuckuck, Tannenmeise.S. Journ. f. Ornithologie 1917, Festschrift für Reichenow. 相似文献
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I. I. Moraru Mioara Manciulea Anca Călugăru Gr. Ghyka L. M. Popescu 《Bioscience reports》1987,7(9):731-736
A novel approach was used to assess the role of phosphoinositide hydrolysis in the mitogenic action of phytohemagglutinin (PHA) or concanavalin A (ConA). The treatment of human peripheral blood leukocytes (PBL) with monospecific antibodies against phospholipase C (PLC) produced a dose-dependent inhibition (up to 100%) of PHA (10 g/ml) or ConA (25 g/ml) proliferative effects. Thus, the activation of membrane-bound PLC is asine-qua-non condition for lectin-induced proliferation of T lymphocytes. The key-role of PLC versus protein kinase C (PKC) is stressed by the fact that the inhibition of PKC with Hidaka's compound H-7 (40 M) produced only a partial blockade (about 25%) of lectin mitogenic effect.To whom correspondence should be addressed. 相似文献
4.
L. M. Popescu C. Cernescu I. I. Moraru St. N. Constantinescu F. Baltã M. Manciulea E. Brãiloiu L. Buzilã 《Bioscience reports》1989,9(5):531-539
A monospecific inhibitory antibody directed to phospholipase C (phosphoinositidase C) blocked the antiviral effect of human interferons alpha and beta when tested on human quiescent fibroblasts challenged with the vesicular stomatitis virus. This action was due to specific inhibition of polyphosphoinositide hydrolysis because (a) the F(ab)2 fragment of the antibody molecule was also inhibitory; (b) excess antibodies directed to phospholipase A2 and to a phosphatidylcholine-preferring phospholipase C did not have any inhibitory effect, and (c) the combination of 12-O-tetradecanoylphorbol-acetate and calcium ionophore A23187 had an interferon-like antiviral effect which was not influenced by the inhibitory anti-phospholipase C antibodies. To avoid an interferon-like effect due to induction of interferon by second messengers, Vero cells, which lack interferon biosynthesis, were also used. Liposomes containing inositol 1,4,5-triphosphate and 1-oleoyl-2-acetyl-rac-glycerol protected Vero cells against the infection with the vesicular stomatitis virus. These results taken together show that phosphoinositide-derived second messengers are involved in triggering the antiviral effect of interferons alpha and beta. 相似文献
5.
H Dolk P De Wals Y Gillerot M F Lechat S Ayme M Cornel A Cuschieri E Garne J Goujard K M Laurence 《Teratology》1991,44(5):547-559
In the period 1980-1987, neural tube defects were two to three times more prevalent in populations covered by EUROCAT registries in the United Kingdom and Ireland (UKI) than in Continental Europe and Malta (CEM). 1864 NTD cases in a total population of 580,000 births in UKI and 455 cases in a population of 380,000 births in CEM were analysed to find if there were differences in the ratio of prevalence rates between UKI and CEM according to site of the defect and association with non-central nervous system (CNS) anomalies. The prevalence rate ratio was high for anencephaly with accompanying spina bifida, iniencephaly, and upper spina bifida, and low for encephalocele, lower spina bifida, and anencephaly without other neural tube defects. There was a greater female excess for anencephaly with accompanying spina bifida, iniencephaly, and upper spina bifida than for other defects in both geographic areas. There was a female excess for encephalocele in UKI but a male excess in CEM. Certain sites (anencephaly with accompanying spina bifida, iniencephaly, and encephalocele) were more likely to have accompanying non-CNS anomalies. The prevalence rate ratio of multiply malformed NTD was in general lower than for isolated NTD but showed the same pattern by site. The prevalence rate ratio was high for multiply malformed anencephaly with accompanying spina bifida, iniencephaly, and upper spina bifida. The sex ratio was similar between isolated and multiply malformed cases when site of the defect is taken into account. It is concluded that the geographic prevalence pattern and sex ratio differ according to site of NTD but do not differ substantially according to whether NTD is isolated or associated with non-CNS anomalies. 相似文献
6.
Gavril Acălugăriţei 《Acta biotheoretica》1986,35(1-2):107-121
The object of this paper is to present an original classification of ontogenetic reproduction. The main general criterion used is the degree and type of phylogenetic differentiation. In relation to this criterion, criteria are given for the classification of the fundamental types of ontogenetic reproduction and for the classification of the types of ontogenetic generation cycles. Between the fundamental types of ontogenetic reproduction and the types of ontogenetic generation cycles there is a hierarchical relationship which shows that the former are components of the latter. Between the well-defined types of ontogenetic reproduction there exist many intermediate types. 相似文献
7.
Suborganellar Localization and Molecular Characterization of Nonproteolytic Degraded Leukoplast Pyruvate Kinase from Developing Castor Oil Seeds 总被引:1,自引:1,他引:0
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Several genes involved in the ability of Synechococcus sp. PCC 7942 to grow under different CO2 concentrations were mapped in the genomic region of rbcLS (the operon encoding the large and small subunits of ribulose-1,5-bisphosphate carboxylase/oxygenase). Insertion of a cartridge encoding kanamycin resistance within open reading frame (ORF) 78, designated ccmJ, located 7 kb upstream of rbcLS, resulted in a kanamycin-resistant, high-CO2-requiring mutant, M3, which does not contain normal carboxysomes. ccmJ shows significant homology to csoS1 encoding a carboxysomal shell polypeptide in Thiobacillus neopolitanus. Analysis of the polypeptide pattern of a carboxysome-enriched fraction indicated several differences between the wild type and the mutant. The amount of the ribulose-1,5-bisphosphate carboxylase/oxygenase subunits was considerably smaller in the carboxysomal fraction of the mutant when compared to the wild type. On the basis of the sequence analyses, ORF286 and ORF466, located downstream of ccmJ, were identified as chlL and chlN, respectively, which are involved in chlorophyll biosynthesis in the dark. 相似文献
8.
Biodiversity is declining worldwide under increasing human pressure. Since the location of and the threats are unevenly distributed and the resources available for conservation are limited, prioritization is essential to reduce the losses. Most conservation efforts until now proved to be ineffective in stopping the present worldwide decline of threatened species. We focus on the European Union (EU) after the repeated enlargements in the last decade, from 15 to 27 countries, by considering the present conservation priorities that have shifted towards a continental scale approach. The situation in the EU indicates that despite the differences in wealth across countries, there are no significant differences in the number and surface of protected areas between them, so re-evaluating conservation priorities at a continental scale and a reallocation of funds is required. A major limitation in priority settings for conservation is data availability. We recommend including in the decision process data provided by phylogeographic studies. This will prevent the decline of populations and species with evolutionary potential from centres of speciation and climate refugia. Recent EU members from central and eastern Europe still retain high biodiversity with a rather good conservation status. A large number of areas with high evolutionary potential identified by phylogeographic studies are located there and should be considered priorities within the context of global changes, as a proactive approach. We recommend a periodic re-evaluation of the status of species and habitats based on current research results, harmonization between the priority species listed in the conventions, directives and Red Lists at both EU and national levels. 相似文献
9.
Feldmane Daina Druva-Lūsīte Ieva Pole Valentīna Butac Mădălina Maria Militaru Mădălina Missa Imants Meiere Diāna Rubauskis Edgars 《Journal of Plant Growth Regulation》2021,40(2):533-540
Journal of Plant Growth Regulation - Sour cherry ‘Latvijas Zemais’ (Prunus cerasus) is a promising dwarfing rootstock for sweet cherries in Latvia, but low growing rate of newly... 相似文献
10.
A. Tăbăran V. A. Balteanu E. Gal D. Pusta R. Mihaiu S. D. Dan 《Animal biotechnology》2013,24(2):105-111
Milk and dairy products are considered the main sources of saturated fatty acids, which are a valuable source of nutrients in the human diet. Fat composition can be adjusted through guided nutrition of dairy animals but also through selective breeding. Recently, a dinucleotide substitution located in the exon 8 of the gene coding for acyl CoA: diacylglycerol acyltransferase 1 (DGAT1), that alters the amino acid sequence from a lysine to an alanine (p.Lys232Ala) in the mature protein, was shown to have a strong effect on milk fat content in some cattle breeds. Therefore, the objectives of this work were to study the occurrence of the DGAT1 p.Lys232Ala polymorphism in Romanian Holstein cattle and Romanian Buffalo breeds and to further investigate its possible influence on fat percentage and fatty acid profiles. The results obtained in this study show that in Romanian Holstein cattle the K allele is associated with increased fat percentage and higher levels of C16:0 and C18:0 fatty acids. The ratio of saturated fatty acids versus unsaturated fatty acids (SFA/UFA) was also higher in KK homozygous individuals, whereas the fractions of C14:0, unsaturated C18 decreased. The DGAT1 p.Lys232Ala polymorphism revealed a high genetic variance for fat percentage, unsaturated C18, C16:0, and SFA/UFA. Although the effect of this polymorphism was not so evident for short chain fatty acids such as C4:0–C8:0, it was significant for C14:0 fatty acids. We concluded that selective breeding of carriers of the A allele in Romanian Holsteins can contribute to improvement in unsaturated fatty acids content of milk. However, in buffalo, the lack of the A allele makes selection inapplicable because only the K allele, associated with higher saturated fatty acids contents in milk, was identified. 相似文献