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991.
Ana Magdalena Hurtado Kristen Hawkes Kim Hill Hillard Kaplan 《Human ecology: an interdisciplinary journal》1985,13(1):1-28
Anthropologists have frequently proposed that sexual division of labor is produced by childcare constraints on women's subsistence work. We present data on the forest activities of Ache women that show that differences in parental investment partially account for variation in food acquisition among individual women. Data also suggest that childcare constraints are important in understanding the sexual division of labor. 相似文献
992.
993.
Streptomyces coelicolor DNA homologous with acyltransferase domains of type I polyketide synthase gene complex 总被引:1,自引:0,他引:1
Katarzyna Kuczek Krzysztof Pawlik Magdalena Kotowska Marian Mordarski 《FEMS microbiology letters》1997,157(1):195-200
An acyltransferase-homologous DNA fragment was amplified in a PCR reaction on a cosmid DNA template from the genomic DNA library of the soil bacterium Streptomyces coelicolor A3(2). The putative amino acid sequence of the fragment resembles acyl-CoA:ACP acyltransferase domains from several bacterial enzymatic complexes of polyketide synthase. There is a high similarity with acyltransferase domains from so-called type I polyketide synthases. Such synthases catalyze production of the aglycone portion of macrolides and polyethers that are important as antibiotics or immunosuppressants. The amplified fragment is considered to be a part of a larger gene complex. 相似文献
994.
995.
Magdalena Frańska Dobrochna Ginter-Kramarczyk Andrzej Szymański Tomasz Kozik Rafał Frański 《International biodeterioration & biodegradation》2009,63(8):1066-1069
Biodegradation of a commercially available mixture of octylphenol ethoxylates (Triton X-100) under the condition of OECD 301E screening test was studied by using electrospray ionisation mass spectrometry. It was found that ethoxylate containing six ethoxylene units (OPEO6) is more resistant to the biodegradation process than other ethoxylates (e.g. than OPEO5 and OPEO7). After 40 days of biodegradation process the signal of OPEO6 was clearly seen, but signals of OPEO5 and OPEO7 were not detected. After 40 days, all OPEOn with n > 4 were converted into carboxylated derivatives. Carboxylated derivatives were observed in negative ion mode as OPEOn-CH2COO? ions. Biodegradation of OPEO5-CH2COOH (carboxylated derivative correspondent of OPEO6) occurred slower than biodegradation of the others, as resulted from obtained ESI mass spectra. 相似文献
996.
Magdalena Endová Milena Masojidková Ivan Rosenberg 《Nucleosides, nucleotides & nucleic acids》2013,32(12):2151-2164
Abstract The use of (chloromethylene)diakylammonium chloride in selective transprotection of N-benzoylated nucleobase derivatives is reported along with the evaluation of the stability of various protecting groups widely used in nucleoside and/or nucleotide chemistry. 相似文献
997.
Sieprawska Apolonia Skórka Magdalena Bednarska-Kozakiewicz Elżbieta Niedojadło Katarzyna Janiak Agnieszka Telk Anna Filek Maria 《Plant and Soil》2021,461(1-2):389-405
Plant and Soil - As drought threatens the yield and quality of maize (Zea mays L.), it is important to dissect the molecular basis of maize drought tolerance. Flavonoids, participate in the... 相似文献
998.
999.
Ratajska A Złotorowicz R Błazejczyk M Wasiutyñski A 《Birth defects research. Part A, Clinical and molecular teratology》2005,73(12):966-979
BACKGROUND: Although normal coronary artery embryogenesis is well described in the literature, little is known about the development of coronary vessels in abnormal hearts. METHODS: We used an animal model of retinoic acid (RA)-evoked outflow tract malformations (e.g., double outlet right ventricle [DORV], transposition of the great arteries [TGA], and common truncus arteriosus [CTA]) to study the embryogenesis of coronary arteries using endothelial cell markers (anti-PECAM-1 antibodies and Griffonia simplicifolia I (GSI) lectin). These markers were applied to serial sections of staged mouse hearts to demonstrate the location of coronary artery primordia. RESULTS: In malformations with a dextropositioned aorta, the shape of the peritruncal plexus, from which the coronary arteries develop, differed from that of control hearts. This difference in the shape of the early capillary plexus in the control and RA-treated hearts depends on the position of the aorta relative to the pulmonary trunk. In both normal and RA-treated hearts, there are several capillary penetrations to each aortic sinus facing the pulmonary trunk, but eventually only 1 coronary artery establishes patency with 1 aortic sinus. CONCLUSIONS: The abnormal location of the vessel primordia induces defective courses of coronary arteries; creates fistulas, a single coronary artery, and dilated vessel lumens; and leaves certain areas of the heart devoid of coronary artery branches. RA-evoked heart malformations may be a useful model for elucidating abnormal patterns of coronary artery development and may shed some light on the angiogenesis of coronary artery formation. 相似文献
1000.
Proteomic analysis of the porcine interphotoreceptor matrix 总被引:2,自引:0,他引:2
Hauck SM Schoeffmann S Deeg CA Gloeckner CJ Swiatek-de Lange M Ueffing M 《Proteomics》2005,5(14):3623-3636
The interphotoreceptor matrix (IPM) is located between photoreceptors and pigment epithelium in the retina and is involved in fundamental functions of the visual cycle. These include visual pigment chromophore exchange, retinal adhesion, metabolite trafficking, and growth factor presentation. In general, IPM preparations are contaminated with intracellular proteins, as has also been described for other body fluids. This study aimed at identifying new components of the IPM by discriminating between truly secreted proteins and proteins that are part of the IPM for secondary reasons. "Soluble" porcine IPM was extracted from retina and pigment epithelium with PBS by two different procedures, followed by extraction with water alone that released "insoluble" IPM matrix sheets. Samples from all preparations were separated by 2-DE and a total of 140 protein spots were identified by MALDI-TOF and/or CapLC Q-TOF MS. Although identified proteins included several already known in the IPM, the majority had not been previously described in this structure. Gene ontology classifications allocated the identified proteins into nine different functional networks. The IPM preparations also included intracellular proteins from cells adjacent to the IPM, which may have resulted from cell disruption. This underlines the experimental difficulties of a biochemical analysis of the IPM as an intact compartment. We show here a strategy for predicting the probability of identified IPM proteins occurring in vivo by combined high-resolution protein separation methods with computational prediction methods. Thus, a set of potentially neuroprotective proteins could be extracted, including PEA-15, peroxiredoxin 5, alpha-B-crystallin, macrophage migration inhibitory factor, 78 kDa glucose-regulated protein (GRP78), protein disulfide-isomerase, and PEP-19, which have not been previously associated with the IPM. Furthermore, with immunohistochemical staining we could confirm the localization of GRP78 in the IPM on porcine eye sections, thus validating the proposed prediction method. 相似文献