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1.
Sandra Danner Christiane Kirchhoff Richard Ivell 《Reproductive biology and endocrinology : RB&E》2009,7(1):67-14
Background
Post-meiotically expressed genes in the testis are essential for the proper progression of spermatogenesis, and yet, aside from the construction of individual transgenic mice using specific promoters to drive reporter plasmids, there are only very limited possibilities for relevant and quantitative analysis of gene promoters. This is due to the special nature of post-meiotic haploid cells, which to date are not represented in any appropriate cell-lines. This article reports the development of novel methodology using isolated and cultured rat seminiferous tubules in a multiwell format, into which promoter-reporter constructs can be introduced by a combination of microinjection and electroporation. 相似文献2.
The ultrastructure and distribution of receptor cells near the mouth and (where present) the pharynx of Hofstenia miamia, Proporus bermudensis, Conaperta thela, and Convoluta convoluta (Acoela) were investigated by transmission electron microscopy and confocal laser scanning microscopy of specimens stained with a fluorescence marker for actin. Five types of monociliary receptors were identified: (1) non‐collared receptors with a single long and narrow ciliary rootlet; (2) non‐collared receptors with a wide main ciliary rootlet and a smaller posterior rootlet; (3) non‐collared receptors with a single wide and hollow ciliary rootlet with a granulated core; (4) Collar (?) receptors with obliquely radial filament bundles in the cell apex and with a single hollow ciliary rootlet composed of numerous strand‐like elements; and (5) Collar receptors lacking a striated rootlet but with a granular body (swallow's nest rootlet). While H. miamia bears the first two receptor types, P. bermudensis has receptors of type 1, 3 and 5, and Cona. thela and Conv. convoluta have receptors of type 3, 4 and 5. The density of receptors is generally highest at the anterior body tip, regardless of where the mouth is located. Most receptor types occur scattered over the whole body but type 2 receptors of H. miamia are restricted to the pharynx and mouth region. The lack of a common receptor type specific for the mouth and pharynx of the investigated species points to an independent origin of the pharynges in Hofsteniidae and in Proporidae and of the mouth tube in Convolutidae. Moreover, the homology of the so‐called collar receptors in Acoela with typical collar receptors in other invertebrates is questioned. 相似文献
3.
4.
A cDNA clone containing the entire coding sequence of a mouse H-2Kd histocompatibility antigen 总被引:14,自引:4,他引:10 下载免费PDF全文
Jean-Louis Lalanne Christiane Delarbre Gabriel Gachelin Philippe Kourilsky 《Nucleic acids research》1983,11(5):1567-1577
We have isolated a cDNA clone carrying a 1560 bp long insert which contains the entire coding and 3' untranslated regions of an H-2K(d) mouse histocompatibility antigen. Its sequence and overal features are described. They point to the existence of unique properties of DNA sequences associated with the H-2K(d) antigen. 相似文献
5.
The nucleotide sequence of a segment of mtDNA from Rattus norvegiens (rat) which contains the genes for tRNAile, tRNAgl and tRNAf-met has been determined. A detailed comparison has been made between this sequence and the corresponding sequences of mouse, human and bovine mtDNAs with regard to the primary and secondary structure of the tRNA genes, the regions connecting the tRNA genes, and the regions flanking the tRNA genes which code for the carboxyl terminus of URF-1 and the amino terminus of URF-2. No differences were found in the nucleotide sequences of the genes for tRNAile, tRNAgln and tRNAf-met in mtDNAs from three different female lines of rats (SASCO-1, SASCO-2 and Wild-UT) that differ by substitutions of 0.8% to 1.8% of their total nucleotides. 相似文献
6.
Cathepsin B, H, L and D activities in liver lysosomes were compared between species. Although cathepsin B and D were detected in bovine, pig, chicken and rat liver, striking species differences were evident for cathepsin H and L. Cathepsin L activity was particularly high in chicken lysosomal extracts, but could not be detected in bovine and pig extracts. Whereas there was no significant cathepsin H activity in bovine extracts, rat liver lysosomal extracts contained large amounts of cathepsin H activity. 相似文献
7.
8.
Cell cultures ofThalictrum
rugosum released their protoberberine alkaloids into the medium, when cells were transferred to fresh medium lacking phosphate. The nutritional factors required and the impact of the cells' physiological state for the alkaloid excretion were analyzed. Cell cultures, having released their alkaloids into the medium, continued to grow when the alkaloid containing medium was replaced by fresh growth medium. 相似文献
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10.
Adrian S. Dobs Christiane Broussolle M. Daniel Lane 《In vitro cellular & developmental biology. Plant》1989,25(2):112-114
Summary The insulin-producing cell line RINm5F, has been used in short-term experiments to evaluate insulin secretion. We sought to
maintain the responsiveness of these cells to stimuli for up to 2 days. We examined the course of new insulin synthesis over
this period by measuring at intervals immunoreactive insulin (IRI) in two parts: IRI in the medium (M) and IRI extracted from
the cells (C). Control cells were incubated in RPMI 1640/2.8 mM glucose/10% fetal bovine serum/200 μg/ml bacitracin (to prevent
insulin degradation). The addition of dibutyryl cAMP 10 mM to the experimental dishes significantly increased total (M+C)
IRI at 48 hr to 37% above the insulin content of the control dishes (p<0.01). Theophylline 10 mM increased total (M+C) IRI
by 24% over control (p<0.05) after 24 hrs. Glucose, glyceraldehyde, leucine, arginine, glucagon and tolbutamide, other stimulants
of insulin production, had no effect. Under the experimental conditions reported here, including the use of bacitracin, IRI
synthesis can be studied for up to 48 hr.
Portions of this study have been published in abstract form for the 47th Annual Meeting of the American Diabetes Association,
Indianapolis, Indiana, 1987.
Supported in part by the American Diabetic Association, Maryland Affiliate. 相似文献