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91.
We have studied, by the gel mobility shift assay, the interaction of DNA binding proteins with a fragment of the proximal promoter (from nucleotides -177 to -47) of the androgen-regulated canine prostate arginine esterase gene. Several shifted bands were obtained using nuclear extracts from various tissues. In the case of the prostate, the intensity of some of the shifted bands was decreased or increased when the extracts were prepared from animals that had been castrated 12 days earlier. Several of the DNA-protein complexes could be assigned to an interaction with part or all of the sequence GGGGGTGGGGG from-124 to -114. We also obtained evidence for the presence of protein(s) interacting with an Sp1 motif present in the same fragment. These results suggest that some ubiquitous factors different from the androgen receptors could be involved in the regulation of the arginine esterase gene. 相似文献
92.
Edward W. Khandjian Consuelo Salomon Nicole Lonard Sandra Tremblay Hans Türler 《Experimental cell research》1992,202(2):464-470
To study alterations in cellular gene expression in mouse kidney cell cultures infected with simian virus 40 (SV40) or polyomavirus, we performed a differential screening of a mouse kidney cDNA library with probes prepared from mRNAs of virus-infected and mock-infected cells. We isolated and characterized cDNA recombinant pKT13 which detected increased mRNA levels in infected cells. Sequence analysis of pKT13 revealed close to 100% homology with the 3'-end of mouse fibronectin (FN) mRNA. Since primary cultures of baby mouse kidney cells have been extensively characterized in our laboratories, we studied FN gene expression at different stages of uninfected and virus-infected cultures. High levels of FN and of its mRNA were found in the kidneys of suckling mice, while in primary cultures of proliferating epithelial kidney cells the expression of FN was very low until the cultures became confluent. Thereafter FN increased and reached high levels in cells which were irreversibly arrested in phase Go and which had apparently exhausted their finite division potential. Infection of confluent cultures with polyomavirus or SV40 resulted in a further stimulation of FN gene expression. However, during abortive infection with SV40, FN mRNA and FN levels decreased with emergence of transformed cells and were low in an established SV40-transformed mouse kidney cell line. These changes in FN gene expression suggest that high levels of FN might be indicative in vivo for terminal differentiation and in vitro for cellular senescence. 相似文献
93.
Isidrogalvia longiflora, a new combination based onAsagraea longiflora, is proposed. It is the first record ofIsidrogalvia from Bolivia. 相似文献
94.
Laurence J. Dorr 《Brittonia》1992,44(1):53-13
In 1843 S. B. Buckley (1809–1884) traveled up the St. Johns River, Florida in search of plants, shells, and possibly other
natural history objects. Buckley encountered many difficulties in interior Florida and his trip did not live up to his original
expectations. It was unfortunate that the took years to distribute his plant specimens, since few botanists or naturalists
had preceded him into that poorly explored region. 相似文献
95.
Laurence J. Dorr 《Brittonia》1992,44(1):1-13
In 1843 S. B. Buckley (1809–1884) traveled up the St. Johns River, Florida in search of plants, shells, and possibly other natural history objects. Buckley encountered many difficulties in interior Florida and his trip did not live up to his original expectations. It was unfortunate that the took years to distribute his plant specimens, since few botanists or naturalists had preceded him into that poorly explored region. 相似文献
96.
Summary The properties of surfactin, a biosurfactant lipopeptide, were highly modified in the presence of inorganic cations. The micellization of surfactin was favoured by monovalent and, especially by divalent cations with a modification of the molecular area at the air-water interface. Haemolysis of erythrocytes by surfactin was enhanced by low concentrations of divalent cations with an increase of the binding of the lipopeptide to membrane. Inorganic ions induced conformational rearrangements probably due to ion-surfactin associations which modify the surface-active properties. 相似文献
97.
The epididymis of adult rams is the primary source of alpha-glucosidase in seminal plasma. Two breeds of rams were selected to ascertain whether the enzyme was under androgenic control during adult life of rams. Opposite variations between serum testosterone and alpha-glucosidase were recorded over a period of 16 months in Suffolk and Finnish Landrace. In addition, the highest percentage of sperm motility was associated with a low alpha-glucosidase content of seminal plasma. Data from this study suggest that seasonal variations of testosterone in adult rams exert a negative control on the presence of alpha-glucosidase in semen. 相似文献
98.
Isolation and characterization of two individual glycoprotein components from human milk-fat-globule membranes.
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Two individual glycoprotein components from human milk-fat-globule membranes (MFGM) has been purified by selectively extracting the membrane glycoproteins followed by lectin affinity chromatography and gel filtration on Sephadex G-200 in the presence of protein-disaggregating agents. The purified glycoprotein components, termed 'epithelial-membrane glycoprotein' (EMGP-155 and EMGP-39) have estimated molecular weights of 155 000 and 39 000 respectively, and yield a single band under reducing conditions on sodium dodecyl sulphate/polyacrylamide gel. EMGP-155 and EMGP-39 contain 21.0% and 7.0% carbohydrate by weight, with fucose (13.5%, 12.4%), mannose (3.7%, 6.2%), galactose (28.5%, 22.6%), N-acetylglucosamine (17.8%, 7.4%) and sialic acid (36.4%, 51.4%) of the carbohydrate moiety respectively. For both the glycoprotein components, aspartic and glutamic acid and serine are the major amino acid residues. 相似文献
99.
A program of reconditioning through walking was prescribed for 130 patients following an exercise test on a treadmill 3 weeks after a myocardial infarction. At 8 and at 12 weeks the patients again underwent an exercise test. The protocol is safe and permits the detection of angina, arrhythmias and dyspnea during the exercise, thus avoiding delays in treatment. The heart rate and the systolic blood pressure were measured at the end of each stage of the test and after 3 minutes of recuperation. About 75% of the patients attained the target energy output of the two submaximal tests (4 and 7 mets at 3 and 8 weeks respectively); an output of 7 mets permits a patient to resume his or her usual daily activities. The results of the tests at 3 and 12 weeks (the latter a maximal test) showed that the probability of an aerobic capacity of 7 mets or greater at 12 weeks is 86% if the 3-week test is completed. Clinical observations alone did not have the same prognostic value 3 weeks after the infarction. 相似文献
100.
Johannes D. Veldhuis Patricia Klase Laurence M. Demers 《Prostaglandins & other lipid mediators》1982,23(3):319-327
Granulosa cells isolated from mature Graafian follicles of swine produced significant quantities of immunoreactive 6-keto-PGF1α under chemically defined conditions in vitro. Luteinizing hormone elicited a dose-dependent stimulation of 6-keto-PGF1α accumulation, but follicle stimulating hormone, prolactin, L-epinephrine, estradiol-17B, or PGE2 were devoid of effect. The time-dependent in vitro production of 6-keto-PGF1α by ovarian cells was susceptible to inhibition by indomethacin, U-51506, cycloheximide, and actinomycin D. These observations implicate granulosa cells in the specific and hormonally regulated production of prostacyclin. 相似文献