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51.
Enhanced proliferation and progesterone production by porcine granulosa cells cultured with pseudorabies virus growth factor (PRGF). 总被引:1,自引:0,他引:1
R Piek?o E L Gregoraszczuk J Lesko F Golais S Stok?osowa 《Journal of physiology and pharmacology》1999,50(1):129-137
The objective of this research was to study possible interactions of pseudorabies virus growth factor (PRGF) with ovarian tissue. Granulosa cells isolated from porcine ovaries were cultured as monolayers for 6 days in a control medium without PRGF and in medium supplemented with different doses of this agent. Increased population density and change towards more fibroblastic-like shape of cells cultured with 10(9) I.U PRGF was observed when compared with control culture. The cells divided significantly faster during 6 days of culture under the influence of 10(3), 10(4), 10(5), 10(6), 10(7), 10(8) and 10(9) I.U./ml of PRGF at a dose dependent manner. PRGF in a dose 10(9) I.U. added to cultured cells isolated from small and medium follicles did not influence progesterone secretion . An increase of progesterone secretion under the influence of PRGF in all investigated days of cultures was observed in cells isolated from large preovulatory follicles. The marked increase in progesterone content in PRGF treated culture in doses of 0.5x10(7), 0.5x10(8), 0.5x10(9) I.U. was observed during 4 and 6 days of culture. The rise of progesterone content was not connected with increased number of secretory cells, but with a stimulation of production per cell. PRGF exerted no visible effect on progesterone secretion by granulosa cells from small and medium follicles cultured for 6 days. The presented in vitro data provide evidence for a local action of PRGF in the follicle depending on the stage of follicular development and duration of exposure. Precise relevance of the interaction of PRGF with follicular development requires further study. 相似文献
52.
Mazhar Ali Nasir Masood Hafiz Muhammad Rashad Javeed Ibrahim Al-Ashkar Khalid F. Almutairi Liyun Liu Muhammad Aqeel Sarwar Karthika Rajendran Ayman EL Sabagh 《Phyton》2022,91(10):2235-2248
Soil amendments containing carbonized materials increase the soil carbon reservoir, influence plant productivity,
and, ultimately, help to clean the environment. There is data on the effect of such additions on soil physicochemical
properties or plant growth, but few studies have focused on how these carbonized materials are distributed by termite species in the soil ecosystem. It is the first comprehensive study of the transportation of biochar (BC) by termite
species under tropical environmental conditions in Pakistan. The present study was carried out to test the hypothesis
that if termite species I) were involved in the distribution of biochar particles II) if yes, then how far these particles
were transported during the study period (10 days) and III) check their preference between the enriched BC (EBC)
and non-enriched BC. BC was enriched with the cattle slurry after its pyrolysis in the study. The results showed that
EBC particles were significantly more widely distributed than non-enriched BC particles, but both types of BC were
transported more than 4 cm (ring 4) within 10 days (at the end of the experiment). The current study also revealed
that EBC was easily attached to the setae, cuticle, and legs of termites, implying that it could potentially be transported over a greater distance. Furthermore, transportation of EBC over larger distances indicated a potential preference of termite species between the EBC and BC particles. During the study, however, the preference among the
termite species was also observed. Under the prevailing study conditions, the Coptotermes heimi and Heteroterme
indicola species transported the EBC further than Microtermes obesi and Odontotermes obesus. These findings
revealed that transportation preferences were observed among the four termite species. In conclusion, the current
study found that termites were involved in the distribution of BC particles, with a preference for EBC and that these
have the potential to transport BC particles more than 4 cm within 10 days. Furthermore, two species Coptotermes
heimi and Heteroterme indicola may be more suitable candidates for EBC transpiration in Pakistani soils. It was
necessary to conduct additional research into the effect of temperature on the transportation process. 相似文献
53.
Micelle‐enhanced spectrofluorimetric method for determination of lacidipine in tablet form; application to content uniformity testing
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A highly sensitive, simple and rapid spectrofluorimetric method was developed for the determination of lacidipine (LCP) in tablets. The proposed method is based on the investigation of the fluorescence spectral behavior of LCP in both sodium dodecyl sulphate (SDS) and the tween‐80 micellar system. In aqueous solutions of acetate buffer (pH 4.5), the fluorescence intensities of LCP were greatly enhanced (ca. 2.4 and 4.3 folds) in the presence of either SDS or tween‐80, respectively. The fluorescence intensity was measured at 444 nm after excitation at 277 nm using either SDS or tween‐80 as a surfactant. The fluorescence–concentration plots were rectilinear over the ranges of 50.0–500.0 ng/ml and 5.0–200.0 ng/ml with lower detection limits of 5.11 and 2.06 ng/ml and lower quantification limits of 17 and 6.87 ng/ml using SDS and tween‐80, respectively. The method was successfully applied to the analysis of LCP in commercial tablets and the results were in good agreement with those obtained with the comparison method. Furthermore, content uniformity testing of pharmaceutical tablets was also conducted. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
54.
RENATA JACH ELŻBIETA MACHANIEC ALFRED UCHMAN 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(3):342-355
Jach, R., Machaniec, E. & Uchman, A. 2011: The trace fossil Nummipera eocenica from the Tatra Mountains, Poland: morphology and palaeoenvironmental implications. Lethaia, Vol. 45, pp. 342–355. The tubular trace fossil Nummipera eocenica Hölder 1989 occurs in a single stratigraphical horizon in Eocene nummulitic limestones of the Tatra Mountains, Poland. The wall of N. eocenica is built of Discocyclina and Nummulities (larger foraminifera) tests, very rarely of the Ditrupa (Polychaeta) tube fragments, bivalve shell fragments, echinoid spines and coralline algae. Morphotype are distinguished on the basis of wall composition and structure. Morphotype A is dominated by fusiform Discocyclina tests, which were preferentially selected by the trace makers for construction of a well‐constructed and resistant wall. Morphotype B contains more robust tests of Nummulites, while morphotype C is dominated by saddle‐shaped tests of Discocyclina. Nummipera eocenica was produced during a period of seafloor stabilization caused by a deepening. The succession of the morphotypes B, A reflects diminishing energy and increasing water depth. Probably morphotype C represents even lower energy environment than morphotype A. The trace fossil is interpreted as a domichnion, which wall was constructed for protection. The trace maker can be considered between polychaetes and crustaceans; however, comparisons to the closest recent analogues, the polychaete Diopatra cuprea or alpheid shrimps, are not satisfactory. □Bartonian, burrow, Carpathians, large foraminifera, trace fossils. 相似文献
55.
ANTHONY RAVEL LAURENT MARIVAUX RODOLPHE TABUCE MUSTAPHA BEN HAJ ALI EL MABROUK ESSID MONIQUE VIANEY‐LIAUD 《Palaeontology》2012,55(5):1035-1041
Abstract: Among the new dental remains from the late Early Eocene of Chambi (Kasserine area, Tunisia) is a large‐sized upper molar of a new bat species, Witwatia sigei nov. sp. (Chiroptera, Vespertilionoidea, Philisidae), described herein. The locality of Chambi has revealed evidence for an early appearance of two modern microchiropteran superfamilies in Africa: Dizzya exsultans, a Philisidae, which is considered to be an archaic Vespertilionoidea, and an indeterminate Rhinolophoidea. In addition to D. exsultans, the new species, W. sigei, is the second representative of the Philisidae in this locality. W. sigei extends back to the late Early Eocene the occurrence of the genus Witwatia, which was previously only reported from the early Late Eocene of the Fayum (BQ‐2, Egypt). By analogy with the largest extant microbats, the large size of Witwatia suggests a tendency to the opportunistic diet of this taxon, thereby contrasting with the strict insectivory characterizing primitive bats found in other continents in the same epoch. 相似文献
56.
Peter Guterstam Fatemeh Madani Hisaaki Hirose Toshihide Takeuchi Shiroh Futaki Samir EL Andaloussi Astrid Gräslund Ülo Langel 《生物化学与生物物理学报:生物膜》2009,1788(12):2509-2517
Cell-penetrating peptides (CPPs) are membrane permeable vectors recognized for their intrinsic ability to gain access to the cell interior. The hydrophobic counter-anion, pyrenebutyrate, enhances cellular uptake of oligoarginine CPPs. To elucidate CPP uptake mechanisms, the effect of pyrenebutyrate on well-recognized CPPs with varying hydrophobicity and arginine content is investigated. The cellular CPP uptake and CPP-mediated oligonucleotide delivery is analyzed by fluorescence activated cell sorting, confocal microscopy, and a cell-based splice-switching assay. The splice-switching oligonucleotide is a mixmer of 2′-O-methyl RNA and locked nucleic acids delivered as a non-covalent complex with 10-fold molar CPP excess. CPP-induced membrane perturbation on large unilamellar vesicles is investigated in calcein release experiments. We observed that pyrenebutyrate facilitates cellular uptake and translocation of oligonucleotide mediated by oligoarginine nonamer while limited effect of pyrenebutyrate on more hydrophobic CPPs was observed. By combining the different experimental results we conclude that the pathway for cellular uptake of oligoarginine is dominated by direct membrane translocation, whereas the pathway for oligoarginine-mediated oligonucleotide translocation is dominated by endocytosis. Both mechanisms are promoted by pyrenebutyrate and we suggest that pyrenebutyrate has different sites of action for the two uptake and translocation mechanisms. 相似文献
57.
D. Jabborova R.Z. Sayyed A. Azimov Z. Jabbarov A. Matchanov Y. Enakiev Alaa Baazeem Ayman EL Sabagh Subhan Danish Rahul Datta 《Saudi Journal of Biological Sciences》2021,28(9):5268-5274
Ginger is used as one of the important ingredients in traditional as well as modern medicine besides as a spice. It boosts immunity and is a rich source of many biologically active substances and minerals. Although it is a medicinally important crop, its productivity is, however, affected due to poor nutrient management and therefore it requires an adequate supply of nutrients in the form of inorganic fertilizers or organic manuring, or a mixture of both. In this context, the present study was aimed to investigate the effect of mineral fertilizers on the content of mineral elements in the ginger rhizome, on soil enzyme activity, and soil properties. Lysimeter experiments were conducted at the Institute of Genetics and Plant Experimental Biology, Kibray, Tashkent region, Uzbekistan. The experiment comprised of four treatments T1 – Control, T2 - N75P50K50 kg/ha, T3 - and T4 - N100P75K75 + B3Zn6Fe6 kg/ha. The results showed that the application of N125P100K100 kg/ha increased rhizome K content by 49%, P content by 20%, and Na content by 58% as compared to control without fertilizer. While the application of N100P75K75 + B3Zn6Fe6 kg/ha showed a significant enhancement in rhizome K, Ca, P, Mg, Na, Fe, Mn, Zn, Cu, Cr, Mo, and Si contents over the control. This treatment also improved active P content by 29%, total P content by 80%, total K content 16%, and N content by 33% content, and the activities of urease, invertase, and catalase activities as compared to control of without mineral fertilizer and control respectively. Thus the application of NPK + BZnFe at the rate of 100:75:75:3:6:6 kg/ha helps in improving macroelements and microelements in the ginger rhizome and activities of soil enzymes that helps in mineral nutrition of the rhizome. 相似文献
58.
Przała J Gregoraszczuk EL Kotwica G Stefańczyk-Krzymowska S Ziecik AJ Blitek A Ptak A Rak A Wójtowicz A Kamiński T Siawrys G Smolińska N Franczak A Kurowicka B Oponowicz A Wasowska B Chłopek J Kowalczyk AE Kaczmarek MM Wacławik A 《Reproductive biology》2006,6(Z1):59-87
The paper summarizes results of a series of studies concerning luteolysis and early pregnancy in pigs. The involvement of the oxytocin (OT)/OT receptor system in the mechanism of corpus luteum (CL) protection during early pregnancy as well as the implication of luteinizing hormone (LH) in the endometrial prostaglandin (PG) release and synthesis are described. In addition, the role of leptin in the regulation of ovarian steroidogenesis and the expression of leptin and its receptor (OB-Rb) genes in hypothalamus, pituitary and reproductive tissues are reported. Moreover, a strong emphasis was placed on the mechanism of PGE2 participation in the local endocrine regulations of reproductive processes occurring in the utero-ovarian area as well as on the vascular endothelial growth factor (VEGF) ligand-receptor system in the ovary and uterus. 相似文献
59.
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