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21.
The present study was carried out to determine the detailed histological and cytological features of the excurrent ducts of
the male reproductive system in the rhesus monkey. The excurrent ducts show a regional difference in their histological features.
The use of some of these features as histological markers and their possible functional significance are discussed.
The epithelial cells in the different components of the excurrent duct system possess cytological features which suggest their
involvement in absorption and the secretion of different products into the lumen. 相似文献
22.
Sodium butyrate produces reversible changes in morphology, growth rate, and enzyme activities of several mammalian cell types in culture. Some of these changes are similar to those produced by agents which increase the intracellular level of adenosine 3',5'-cyclic monophosphate (cAMP) or by analogs of cAMP. Sodium butyrate increases the intracellular level of cAMP by about two fold in neuroblastoma cells; therefore, some of the effects of sodium butyrate on these cells may in part be mediated by cAMP. Sodium butyrate appears to have properties of a good chemotherapeutic agent for neuroblastoma tumors because the treatment of neuroblastoma cells in culture causes cell death and "differentiation"; however, it is either innocuous or produces reversible morphological and biochemical alterations in other cell types. 相似文献
23.
The incorporation of [35S]methionine into ovalbumin, a protein containing NH2-terminal N-acetylglycine, has been studied in chicken oviduct magnum cells. The purification of [35S]methionine-labeled ovalbumin from total oviduct proteins was accomplished by dialysis of a crude extract at pH 3.6 followed by chromatography on carboxymethyl cellulose. The radioactive ovalbumin eluted from the column in three peaks (P0, P1, and P2-containing 0, 1, and 2 moles of phosphate, respectively, per mole of ovalbumin). The kinetics of labeling of peaks P0 and P1 showed that the ratio of radioactivity in NH2-terminal methionine to total incorporation was greater at 2 min of labeling than at later times. The transient labeling of the NH2-terminus of ovalbumin with methionine indicates that methionine is the initiator amino acid for the synthesis of this protein, which in its mature form contains NH2-terminal N-acetylglycine. 相似文献
24.
Food preference as well as feeding efficiency studies of the carabid predator revealed that the grub of theChlaenius bioculatus
Chaud preferred mostPolytella gloriosae F. larvae in both 2nd and 3rd instar.Tarache tropica
Guénée was preferred least by the grub predator in both instar.T. tropica was found toxic and grubs of the predator died after consumption.
Résumé Les préférences alimentaires, de même que l'efficacité prédatrice deChlaenius bioculatus Chaud, montrent que ce carabide prédateur préfère le plus les larves dePolytella gloriosae F. du 2e et 3e stade.Tarache tropica Guénée est le moins attaqué aux deux stades.T. tropica est toxique et les larves du prédateur meurent après sa consommation.相似文献
25.
Epigenetic mechanisms of plant stress responses and adaptation 总被引:3,自引:0,他引:3
Pranav Pankaj Sahu Garima Pandey Namisha Sharma Swati Puranik Mehanathan Muthamilarasan Manoj Prasad 《Plant cell reports》2013,32(8):1151-1159
Epigenetics has become one of the hottest topics of research in plant functional genomics since it appears promising in deciphering and imparting stress-adaptive potential in crops and other plant species. Recently, numerous studies have provided new insights into the epigenetic control of stress adaptation. Epigenetic control of stress-induced phenotypic response of plants involves gene regulation. Growing evidence suggest that methylation of DNA in response to stress leads to the variation in phenotype. Transposon mobility, siRNA-mediated methylation and host methyltransferase activation have been implicated in this process. This review presents the current status of epigenetics of plant stress responses with a view to use this knowledge towards engineering plants for stress tolerance. 相似文献
26.
J S Prasad R R Erickson D L Crankshaw J L Holtzman 《Archives of biochemistry and biophysics》1986,248(2):639-645
In the presence of ATP hepatic microsomes sequester calcium. This sequestration is thought to be important in the modulation of free cytosolic calcium concentration. We find that on the addition of NADPH the uptake of calcium by the hepatic microsomes is inhibited 27-85%. This inhibition is reversed by the addition of 1 mM reduced glutathione (85-91% of control), incubation under a nitrogen atmosphere (112% of control), or incubation in a 80% carbon monoxide/20% oxygen atmosphere (75% of control). Superoxide dismutase had no effect on the inhibition, while catalase reversed the inhibition by 35%. The addition of 1 mM reduced glutathione at 2 and 5 min after the addition of NADPH led to uptakes of calcium which paralleled the uptake seen when the reduced glutathione was added at the beginning of the incubation. The effect of reduced glutathione showed saturation kinetics with a Km of 10 microM. Together these data suggest that cytochrome P-450 reduces the activity of the microsomal ATP-dependent calcium pump both by the production of hydrogen peroxide and by the direct oxidation of the protein thiols. The reversal of this effect by reduced glutathione appears to be enzymatically catalyzed. 相似文献
27.
Saluja P Yelchuri RK Sohal SK Bhagat G Paramjit Prasad GS 《Antonie van Leeuwenhoek》2012,101(4):733-742
Four yeast strains (APSS 805, APSS 806, APSS 815 and AP-18) belonging to a novel Torulaspora species were isolated from coal mine soils of Singareni in Andhra Pradesh state, India. Another strain (PBA-22) was isolated
from agricultural field soil from Gujarat state, India. The vegetative cells of all these strains were round, haploid and
produced asci by conjugation between independent cells or mother cell and bud, with rough ascospores, suggesting their possible
relation to ascomycetous yeast genus Torulaspora. Phylogenetic analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and Internal Transcribed Spacer (ITS) regions
revealed that, among the five strains, three viz. APSS 805, APSS 806 and APSS 815 have identical sequences. The other two
strains (AP-18 and PBA-22) differed from the other three strains in less than 1% nucleotide substitutions in the combined
D1/D2 domain and ITS sequences, indicating that all of them (five strains) may belong to the same species. These five strains
were closely related to Torulaspora globosa, but showed more than 3–7% sequence divergence from T. globosa and all other species in the genus Torulaspora in the combined sequence analysis of D1/D2 domain and ITS region of rRNA gene. In addition, these strains also showed distinct
microsatellite finger-printing pattern from related species and differed in several physiological responses suggesting that
these strains belong to a novel species of Torulaspora. We propose to name these strains as Torulaspora indica sp. nov., and designate APSS 805T = MTCC 9772 T = CBS 12408 T as the type strain of this novel species. The Mycobank number of the novel species is MB 563738. 相似文献
28.
Cyclo (His-Pro) (10 ng/ml), inhibits KCl (59 mM) or thyrotropin-releasing hormone (10 ng/ml) stimulated, but not basal, release of prolactin from rat hemipituitaries . However, cyclo (His-Pro) has no effect on the basal or stimulated release of thyrotropin and growth hormone. Cyclo (His-Pro) does not inhibit the binding of thyrotropin-releasing hormone to pituitary membrane suggesting that cyclo (His-Pro) inhibition of prolactin release is not mediated via the pituitary TRH-receptor. 相似文献
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