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1.

Background  

Coordinated differentiation of the endometrial compartments in the second half of the menstrual cycle is a prerequisite for the establishment of pregnancy. Endometrial stromal cells (ESC) decidualize under the influence of ovarian progesterone to accommodate implantation of the blastocyst and support establishment of the placenta. Studies into the mechanisms of decidualization are often hampered by the lack of primary ESC. Here we describe a novel immortalized human ESC line.  相似文献   
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The interactions of Paecilomyces lilacinus strain 251 with the arbuscular mycorrhizal fungus Glomus intraradices and their significance for the control of Meloidogyne incognita on tomato were investigated in greenhouse experiments. Application of P. lilacinus had no effect on the frequency and intensity of tomato root colonization by G. intraradices. Likewise, the decline of the nematophagous fungus densities after single application in soil was not affected by the presence of the mycorrhizal fungus. Single application of P. lilacinus, as pre-planting soil treatment, resulted in significant reduction of nematode damage. In contrast, mycorrhizal inoculation did not provide sufficient biocontrol. Combined application of the two agents did not enhance root protection compared to single treatments. Double treatment of mycorrhized seedlings with P. lilacinus, as seedling drench and pre-planting soil treatment, 4 and 1 week before transplanting, respectively, resulted in the highest reduction of the nematode damage. These results indicate the potential of the commercial P. lilacinus strain 251 and mycorrhiza for integration in nematode control strategies.  相似文献   
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One of the intermediates involved in dissociation and reassociation of the subunits of the type II cAMP-dependent protein kinase has been characterized. This intermediate can be generated when the protein kinase is prepared from the isolated catalytic subunit (C) and the isolated regulatory subunit-[3H]cAMP complex (R2-[3H]cAMP4) by dialysis for 18 h followed by gel filtration. The intermediate, which could be separated from the holoenzyme and the isolated subunits by polyacrylamide gel electrophoresis, had an apparent molecular weight of 149,000, consistent with an R2C form. Following electrophoresis, measurements of R and bound nucleotide indicated that R2C was half-saturated with [3H]cAMP. The bound [3H]cAMP exhibited biphasic dissociation kinetics indicating that both types of cAMP binding sites were occupied. These findings suggested that the intermediate is R2C-cAMP2. This intermediate was not seen when the dialysis time was increased to 5 days, but could be observed when cAMP was added to the holoenzyme or when holoenzyme was mixed with R2cAMP4 and cAMP. The presence of two occupied cAMP binding sites on this intermediate suggests that there is minimal cooperativity between the two members of the regulatory subunit dimer, i.e. one member of the dimer binds 2 molecules of cAMP while the other binds C.  相似文献   
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Variants shown by the orientation of the cover-plate and of the superior articular facets of the sacrum have a considerable influence on the lumbosacral biostatistics. This can be illustrated by parallelograms of forces. If we assume a certain force stressing upon the sacrum, we are able to calculate the distribution of stress upon the cover-plate and the articular facets by help of the size and the orientation of these weight bearing faces.  相似文献   
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The site-specific phosphorylation of bovine histone H1 by protein kinase C was investigated in order to further elucidate the substrate specificity of protein kinase C. Protein kinase C was found to phosphorylate histone H1 to 1 mol per mol. Using N-bromosuccinimide and thrombin digestions, the phosphorylation site was localized to the globular region of the protein, containing residues 71-122. A tryptic peptide containing the phosphorylation site was purified. Modification of the phosphoserine followed by amino acid sequence analysis demonstrated that protein kinase C phosphorylated histone H1 on serine 103. This sequence, Gly97-Thr-Gly-Ala-Ser-Gly-Ser(PO4)-Phe-Lys105, supports the contention that basic amino acid residues C-terminal to the phosphorylation site are sufficient determinants for phosphorylation by protein kinase C.  相似文献   
9.
The ATP production of human erythrocytes in the steady state (approximately 2 mmoles . 1 cells-1 . h-1, 37 degrees C, pHi 7.2) is maintained by glycolysis and the ATP consumption is essentially limited to the cell membrane. About 25% of the ATP consumption is used for ion transport ATPases. The bulk of the ATP consuming processes in intact erythrocytes remains poorly understood. "Isotonic" erythrocyte membranes prepared under approximate intracellular conditions after freeze-thaw hemolysis have high (Ca2+, Mg2+)-ATPase activities (80% of the total membrane ATPase activity). There is a great discrepancy between the high capacity of the (Ca2+, Mg2+)-ATPase in isotonic membranes and the actual activity in the intact cell. The (Ca2+, Mg2+)-ATPase of isotonic membranes has a "high" Ca2+-affinity (Ka less than 0.5 microM) and a "low" Mg-ATP affinity (Km approximately 760 microM). This state of (Ca2+, Mg2+)-ATPase is caused by the association of calmodulin and 30000 Dalton polypeptides (ATP affinity modulator protein). Hypotonic washings of isotonic membranes result in a loss of the 30 kD polypeptides. EGTA (0.5 mM) extracts derived from isotonic membranes contain the 30 kD modulator protein and restore the properties of the (Ca2+, Mg2+)-ATPase of hypotonic membrane preparations to the isotonic characteristics. The Mg-ATP affinity modulator protein is assumed to form a complex with calmodulin and (Ca2+, Mg2+)-ATPase.  相似文献   
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