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161.
Ogorzalek A 《The International journal of developmental biology》2008,52(2-3):135-139
Embryological research at the University of Wroclaw covers hormonal control of metamorphosis, primarily invertebrate embryology and gametogenesis, vertebrate myogenesis and the developmental impact of external factors. Developmental studies at the University of Wroclaw are a continuation of those conducted at the former Jan Kazimierz (Johannes Casimirus) University in Lwow before World War II. The Wroclaw embryological school is best characterized as comparative embryology which approaches embryonic development experimentally as well as through the analysis of its natural diversity. 相似文献
162.
Nicklas Samils Antoni Olivera Eric Danell Susan J. Alexander Christine Fischer Carlos Colinas 《Economic botany》2008,62(3):331-340
The Socioeconomic Impact of Truffle Cultivation in Rural Spain. Commercial black truffle (Tuber melanosporum) plantations have been promoted in Europe with the intention of benefiting rural economies while conserving biodiversity through the expansion of oak woodlands. In this context, a socioeconomic study was conducted around the town of Sarrión in eastern Spain, where government subsidies have supported oak reforestation and truffle cultivation in unproductive hilly areas since 1987. Currently there are about 4,500 ha of truffle orchards in the surrounding county and 530 members in the local truffle association, which has provided a key forum for truffle cultivators to share technical, financial and administrative experiences. Structured interviews were carried out in 2002 with a number of orchard owners, as well as representatives of financial and governmental institutions. Truffles, which are harvested using trained dogs, typically fetch local cultivators average prices of 220–670 EUR/kg, although retail prices of high-quality specimens may reach twice this amount. In addition to the direct economic impact, an increase in local land prices was also documented, as well as a tendency for continued expansion of truffle orchards, and thus oak reforestation. In conclusion, the promotion of truffle cultivation through autonomous community and provincial government subsidies, in conjunction with support by local banks, a dedicated local truffle association, and growing interest on behalf of local farmers, seems to have achieved the mutual goals of biodiversity conservation and improving the rural economy in this region of Spain. 相似文献
163.
The molecular and cellular basis of the psychotropic actions of adrenal corticosteroids is poorly understood. Previously,
we reported that modulation of large conductance Ca2+-activated potassium channel (BK-channel) function by glucocorticoids can be recapitulated in human embryonic kidney293 (HEK293)
cells (J Physiol 537:57, 2001). In the present paper, we examined the effect of dexamethasone on the expression of candidate
mediator proteins of glucocorticoid action, dex-ras1 and serum and glucocorticoid inducible protein kinase 1 (SGK), in HEK293
cells. Dex-ras1 mRNA was readily detectable under basal conditions however, no changes of dex-ras1 mRNA expression occurred
upon exposure to 100 nM of dexamethasone for 2 h. In contrast, a 2.5-fold increase of SGK mRNA was found under similar conditions.
Total levels of cellular SGK protein were unaltered upon exposure to dexamethasone, but a marked increase of SGK in a Triton-X100
insoluble fraction was observed. BK-channel α-subunits could not be co-immunoprecipitated with SGK. In summary, SGK, but not
dex-ras1, mRNA is rapidly induced by glucocorticoid stimulation in HEK293 cells. However, there appears to be no direct protein-protein
interaction between SGK and BK-channel α-subunits.
Presented to mark the 70th birthday of Professor George Fink.
Special issue article in honor of George Fink. 相似文献
164.
Tomoaki Hishida Eric Vazquez-Ferrer Yuriko Hishida-Nozaki Ignacio Sancho-Martinez Yuta Takahashi Fumiyuki Hatanaka Jun Wu Alejandro Ocampo Pradeep Reddy Min-Zu Wu Laurie Gerken Reuben J. Shaw Concepcion Rodriguez Esteban Christopher Benner Hiroshi Nakagawa Pedro Guillen Garcia Estrella Nu ez Delicado Antoni Castells Josep M. Campistol Guang-Hui Liu Juan Carlos Izpisua Belmonte 《蛋白质与细胞》2019,10(7):485
Identification of the precise molecular pathways involved in oncogene-induced transformation may help us gain a better understanding of tumor initiation and promotion. Here, we demonstrate that SOX2+ foregut epithelial cells are prone to oncogenic transformation upon mutagenic insults, such as KrasG12D and p53 deletion. GFP-based lineage-tracing experiments indicate that SOX2+ cells are the cells-of-origin of esophagus and stomach hyperplasia. Our observations indicate distinct roles for oncogenic KRAS mutation and P53 deletion. p53 homozygous deletion is required for the acquisition of an invasive potential, and KrasG12D expression, but not p53 deletion, suffices for tumor formation. Global gene expression analysis reveals secreting factors upregulated in the hyperplasia induced by oncogenic KRAS and highlights a crucial role for the CXCR2 pathway in driving hyperplasia. Collectively, the array of genetic models presented here demonstrate that stratified epithelial cells are susceptible to oncogenic insults, which may lead to a better understanding of tumor initiation and aid in the design of new cancer therapeutics. 相似文献
165.
Carey Philip G. Sargent Angela J. Taberner Antoni Martínez Ramón Guillem Moyà Gabriel 《Hydrobiologia》2001,448(1-3):193-201
On the island of Mallorca, anchihaline lagoons, meromictic in character, are common in the flooded coastal karst. These subterranean lagoons, containing important populations of crustacea, maintain a connection, albeit tenuous, to the sea. Thus, the first truly quantitative study of marine ciliates inhabiting anchihaline lagoons was undertaken between April 1996 and April 1997. Physical and chemical measurements were taken in-situ, together with water samples for faunal analysis in each of four stratified lakes. These lagoons typically displayed a temperature inversion, an increase in conductivity and a decrease in dissolved oxygen concentration with depth. Ciliates were present in all lagoons studied, with a total of nine species recorded. All were assigned to known taxa. Spatial distribution of the trophic cells was noteworthy with populations clearly stratified within the water column, most being found at the waters surface, sometimes in association with rafts of floating calcite crystals, or in the sediment. Only on one occasion were ciliates recorded in mid-water. Abundance was very low, typically <1 ciliate cm–3. The floating calcite crystals may form a delimitable biotope for ciliate populations. The role of the cyst in maintaining populations of ciliates in these cave waters is discussed. 相似文献
166.
Teresa Pérez Antoni Gómez Raimon Sanmarti Odette Vi?as Guadalupe Ercilla Isabel Haro 《Letters in Peptide Science》2002,9(6):291-300
Antifilaggrin autoantibodies (AFA) have described to be the most specific markers of rheumatoid arthritis (RA) and epitopes containing citrulline within the sequence of filaggrin identified as major antigenic sites recognised by AFA. In this paper we confirm that citrulline is an essential constituent of filaggrin related antigenic determinants recognised by RA specific autoantibodies, thus having an important role for the development of filaggrin peptides based serological tests. Moreover, we describe our findings on the comparative conformational analysis of filaggrin (306–324) peptide sequence and an analogue in which two arginines were simultaneously substituted by citrulline carried out by Circular Dichroism (CD) and Fourier-Transform Infrared Spectroscopy (FTIR). Results might contribute to the understanding of the structural features that may be important to explain the enhanced binding characteristics of citrullinated peptides to the autoantibodies in rheumatoid arthritis. 相似文献
167.
168.
169.
Antoni Sicras-Mainar Javier Rejas Ruth Navarro Milagrosa Blanca Ángela Morcillo Raquel Larios Soledad Velasco Carme Villarroya 《Arthritis research & therapy》2009,11(2):R54-14
Introduction
The objective of this study was to analyze health care and non-health care resource utilization under routine medical practice in a primary care setting claims database and to estimate the incremental average cost per patient per year of fibromyalgia syndrome (FMS) compared with a reference population. 相似文献170.