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1.
Three Approaches to the Study of Language and Gender 总被引:1,自引:0,他引:1
Bonnie McElhinny 《American anthropologist》2003,105(4):848-852
Gender across Languages: The Linguistic Representation of Women and Men. Vol. 2. Marlis Hellinger and Hadumod Bußmann eds. Amsterdam: John Benjamins, 2002. 348 pp.
Gender Identity and Discourse Analysis. Lia Litosseliti and Jane Sunderland eds. Amsterdam: John Benjamins, 2002. 335 pp.
Talking Gender and Sexuality. Paul McIlvenny. ed. Amsterdam: John Benjamins, 2002. 327 pp. 相似文献
Gender Identity and Discourse Analysis. Lia Litosseliti and Jane Sunderland eds. Amsterdam: John Benjamins, 2002. 335 pp.
Talking Gender and Sexuality. Paul McIlvenny. ed. Amsterdam: John Benjamins, 2002. 327 pp. 相似文献
2.
Melinda Bonnie Fagan 《Biology & philosophy》2012,27(2):179-213
Stem cell biology and systems biology are two prominent new approaches to studying cell development. In stem cell biology,
the predominant method is experimental manipulation of concrete cells and tissues. Systems biology, in contrast, emphasizes
mathematical modeling of cellular systems. For scientists and philosophers interested in development, an important question
arises: how should the two approaches relate? This essay proposes an answer, using the model of Waddington’s landscape to
triangulate between stem cell and systems approaches. This simple abstract model represents development as an undulating surface
of hills and valleys. Originally constructed by C. H. Waddington to visually explicate an integrated theory of genetics, development
and evolution, the landscape model can play an updated unificatory role. I examine this model’s structure, representational
assumptions, and uses in all three contexts, and argue that explanations of cell development require both mathematical models
and concrete experiments. On this view, the two approaches are interdependent, with mathematical models playing a crucial
but circumscribed role in explanations of cell development. 相似文献
3.
4.
Human λ light chain locus: Organization and DNA sequences of three genomicJ regions 总被引:14,自引:0,他引:14
Evidence for the genomic organization of human lambda light chain joining (J) region gene segments is presented. A mouse J probe was used in Southern hybridizations to localize joining region sequences in a cosmid clone containing the genomic cluster of six human lambda constant (C) region gene segments. The results of these hybridizations suggest the presence of at least one J gene segment upstream from each constant region gene segment. The DNA sequences indicate that the human JI, J2, and J3 gene segments have consensus nonamer and heptamer sequences, proposed to be involved in V-J joining, are capable of encoding the known amino acid sequences for the respective J peptides, and have a sequence which could give functional RNA splice site at the end of their coding regions. Our data show that a single functional J is located 1.3 or 1.6 kb upstream of each of the C gene segments known to encode the Mcg, Kern– Oz–, and Kern–Oz+ isotypes. Therefore, the gene organization of this region of the human lambda locus is J1 CI -J2C2-J3C3. The DNA sequences ofJ
1,J
2, andJ
3 presented in this paper establish that a singleJ
gene segment precedes each expressed C gene segment, and support a model for the evolution of the human JC clusters where JICI andJ2C2-J3C3. arose from different ancestral JC units. 相似文献
5.
Raymond R. Wilson Jr Joseph F. Siebenaller Bonnie J. Davis 《Biochemical Systematics and Ecology》1990,18(7-8):565-572
The heart-type lactate dehydrogenase (LDH-B4) homologs of two species of Nezumia and eight species of Coryphaenoides are isomobile on two commonly used electrophoretic buffer systems. To test the hypothesis that the homologs possess the same primary structures, the allozymes from N. bairdii and four species of Coryphaenoides were purified by affinity chromatography on an oxamate aminohexyl Sepharose column and digested with trypsin. The resulting peptide mixtures were then mapped using reversed-phase high-performance liquid chromatography. The peptide maps of the enzyme homologs indicate that the overall similarity of the homologs is high, but unique peptides in each species indicate that the allozymes are not identical in primary structure. 相似文献
6.
The response of a bumblebee goby,Brachygobius sabanus,to chemical stimuli from injured conspecifics 总被引:1,自引:0,他引:1
Synopsis
Brachygobius sabanus move less often and spend less time swimming when they detect chemicals released from injured conspecifics. This resembles the alarm response found in ostariophysan fishes, darters, and at least one other gobiid. Chemicals from injured Poecilia reticulata do not induce an alarm response in B. sabanus. 相似文献
7.
Purified erythroid progenitor cells (CFU-E) were used to study in vitro the production of the proteins present in the plasma membrane and the membrane skeleton. At different stages of erythropoiesis incorporation of [35S]methionine was measured and membranes were isolated. Whereas incorporation in the total protein mass of the cells increased during erythropoiesis, the labeling of the membrane protein fraction decreased. The major erythrocyte membrane proteins were synthesized already in the CFU-E and continued to be made till the orthochromatic erythroblast stage. Band 3 protein, however, was made at a much lower rate. The incorporation in the late stages was only 5% of that in the CFU-E. The major changes in the protein composition of the membrane and its adherent skeleton occurred at the enucleation step. 相似文献
8.
The transbilayer distribution of phosphatidylethanolamine in erythroid plasma membranes during erythropoiesis 总被引:1,自引:0,他引:1
W Nijhof P H van der Schaft P K Wierenga B Roelofsen J A Op den Kamp L L van Deenen 《Biochimica et biophysica acta》1986,862(2):273-277
Fluorescamine was used to assess the transbilayer distribution of phosphatidylethanolamine in the plasma membrane of murine erythroid progenitor cells, CFU-E (colony-forming unit erythroid), at different stages of their differentiation pathway. Intact cells were exposed to increasing concentrations of fluorescamine and the amount of labeled phosphatidylethanolamine was determined by measuring the fluorescence intensity of its fluorescamine derivative. A semilogarithmic plot of the dose-response curve revealed three different pools of phosphatidylethanolamine, representing its fractions in, respectively, the inner- and outer monolayers of the plasma membrane and subcellular membrane systems. These results show that 9-11% of the total cellular phosphatidylethanolamine is present in the outer leaflet and 9-10% of it is located in the inner leaflet of the plasma membrane in early as well as late erythroblasts. This symmetric distribution of phosphatidylethanolamine over the two halves of the bilayer in the plasma membrane of CFU-E is very similar to that observed earlier in the plasma membrane of friend erythroleukaemic cells (Rawyler, Van der Schaft, Roelofsen and Op den Kamp (1985) Biochemistry 24, 1777-1783). These observations imply that the characteristic asymmetric distribution of phosphatidylethanolamine, as is found in mature erythrocytes, is accomplished at a very late stage of erythropoiesis and possibly during enucleation of the cells or shortly thereafter. 相似文献
9.
Patsy M. Brannon Bonnie M. Orrison Norman Kretchmer 《In vitro cellular & developmental biology. Plant》1985,21(1):6-14
Summary Rat pancreatic acinar cells were isolated and cultured in Ham's F12 medium with 15% bovine calf serum. Caerulein, insulin,
somatostatin, and dexamethasone (DEX) had no effect on intracellular or secreted amylase in these cultured cells. A serum-free
medium, using Waymouth's MB 752/1 supplemented with albumin, epidermal growth factor (EGF), DEX, and HEPES, was then developed
to avoid serum factors that might mask hormonal effects. In this SF medium, pancreatic acinar, cells maintained the morphological
and ultrastructural characteristics of freshly isolated cells and secreted amylase in response to the secretagogue, carbamyl
choline. Insulin, at a concentration of 1 μg/ml, significantly increased intracellular and secreted amylase activity after
3 d. This model cell system can be used to study the regulation of the synthesis of amylase and other pancreatic enzymes in
vitro. 相似文献
10.
Erythroid progenitor cells, CFU-E (colony-forming-unit-erythroid), were isolated to practical homogeneity by a combination of three enrichment procedures. CFU-E were generated in large amounts in spleens of mice previously bled and treated with the erythropoiesis-suppressing drug thiamphenicol. The average CFU-E concentration in spleens from mice 4 d after the thiamphenicol-treatment was 10%. These CFU-E were separated from lymphocytes, erythrocytes, and granulocytes and their progenitor cells by centrifugal elutriation and Percoll density gradient centrifugation. A three- to five-fold enrichment was obtained by elutriation, leading to a CFU-E concentration of 45%. With the Percoll gradient another twofold enrichment was achieved, providing us with a 80-100% CFU-E cell population. The overall recovery of CFU-E was 60- 70%. This is a cheap, rapid, and highly efficient method of obtaining large quantities of viable CFU-E. The sequential formation of two-, four-, and eight-cell colonies from CFU-E cultured in vitro was studied. These cells enable us to study the biochemical changes occurring in the differentiation process of an erythroid progenitor cell induced by the hormone erythropoietin. The morphological and some physical and biological properties of these cells are presented. 相似文献