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M A Akbarsha B Manivannan K S Hamid B Vijayan 《Indian journal of experimental biology》1990,28(5):421-426
Dry leaf powder of A. paniculata, when fed orally to male albino rats, at a dose level of 20 mg powder per day for 60 days, resulted in cessation of spermatogenesis, degenerative changes in the seminiferous tubules, regression of Leydig cells and regressive and/or degenerative changes in the epididymis, seminal vesicle, ventral prostate and coagulating gland. There was reduction in the weight and fluid content of the accessory glands. The treatment also resulted in accumulation of glycogen and cholesterol in the testis, and increased activities of lactate dehydrogenase in testis and alkaline phosphatase in testis and ventral prostate. The results suggest antispermatogenic and/or antiandrogenic effect of the plant. 相似文献
23.
Intermolecular base-paired interaction between complementary sequences present near the 3'' ends of 5S rRNA and 18S (16S) rRNA might be involved in the reversible association of ribosomal subunits. 总被引:6,自引:6,他引:0 下载免费PDF全文
A A Azad 《Nucleic acids research》1979,7(7):1913-1929
Highly conserved sequences present at an identical position near the 3' ends of eukaryotic and prokaryotic 5S rRNAs are complementary to the 5' strand of the m2(6)A hairpin structure near the 3' ends of 18S rRNA and 16S rRNA, respectively. The extent of base-pairing and the calculated stabilities of the hybrids that can be constructed between 5S rRNAs and the small ribosomal subunit RNAs are greater than most, if not all, RNA-RNA interactions that have been implicated in protein synthesis. The existence of complementary sequences in 5S rRNA and small ribosomal subunit RNA, along with the previous observation that there is very efficient and selective hybridization in vitro between 5S and 18S rRNA, suggests that base-pairing between 5S rRNA in the large ribosomal subunit and 18S (16S) rRNA in the small ribosomal subunit might be involved in the reversible association of ribosomal subunits. Structural and functional evidence supporting this hypothesis is discussed. 相似文献
24.
Trisomic analysis of ribosomal RNA cistron multiplicity in barley (Hordeum vulgare L.) 总被引:1,自引:1,他引:0
Ribosomal RNA cistron numbers in all the seven primary trisomics of diploid barley (Hordeum vulgare L.) were determined by DNA-rRNA filter hybridisation. Trisomies for the nucleolus organiser (NO) chromosomes 6 and 7 showed the highest levels of rDNA (DNA complementary to rRNA) indicating the localisation of rRNA cistrons on the NOs. Chromosomes 6 and 7 possessed 1,580 and 2,690 rRNA (18S + 5.8S + 26S) cistrons respectively. Trisomics for the other chromosomes (except for 3) also displayed levels of rDNA significantly higher (22–32%) than the diploid controls although the dosage of NOs was not altered. These non-specific increases were also present in trisomics for 6 and 7 (NOs) which showed further increases equivalent to their respective contributions. The nonspecific increases due to trisomy is indicative of rDNA compensation. Such increases did not persist in diploid sibs of the trisomics, demonstrating the nonheritable nature of the compensation. 相似文献
25.
Mohyeddin Mandana Bonab Kamran Alimoghaddam Fatemeh Talebian Syed Hamid Ghaffari Ardeshir Ghavamzadeh Behrouz Nikbin 《BMC cell biology》2006,7(1):14-7
Background
A hot new topic in medical treatment is the use of mesenchymal stem cells (MSC) in therapy. The low frequency of this subpopulation of stem cells in bone marrow (BM) necessitates their in vitro expansion prior to clinical use. We evaluated the effect of long term culture on the senescence of these cells. 相似文献26.
Nazemian Maryam Hojati Vida Zavareh Saeed Madanchi Hamid Hashemi-Moghaddam Hamid 《International journal of peptide research and therapeutics》2020,26(1):259-269
International Journal of Peptide Research and Therapeutics - Chemotherapy using drug delivery systems can target tumor cells selectively and do not affect normal cells. In this paper, a specific... 相似文献
27.
Kumar Deepak Jain Ravikumar Shahjahan Banerjee Sabyasachi Prabhu Shriganesh S. Kumar Ranjan Azad Abul K. Roy Chowdhury Dibakar 《Plasmonics (Norwell, Mass.)》2020,15(6):1925-1934
Plasmonics - We present enhancement of operational bandwidths of planar terahertz metasurfaces by incorporating a complex unit cell that consists of a pair of concentric ring resonators. The inner... 相似文献
28.
The current study investigated the effect of developmental stages on the chemical composition and the antioxidant activity of fifteen crude oil samples obtained from Pistacia atlantica Desf. leaves, galls, and fruits. Twelve fatty acids were detected by GC/FID, linolenic acid (C18 : 3) was the major fatty acid detected in leaves crude oils that registered [41.73 % (P<0.05)] on the last stage. The best content of tocopherols and carotenoids was recorded at the last stage for leaves and galls oils, respectively, with values of [1.530±0.01, 0.52±0.01 (P<0.05) mg α‐tocopherol equivalent/g DW] and [86.60±0.95, 69.15±0.13 (P<0.05) μg β‐carotene equivalent/g DW]. For fruits oils, the content varied depending on the levels of fruits maturation. The results from DPPH, FRAP, and ABTS assays revealed that the antioxidant activity increased with the increasing content of tocopherols and carotenoids in leaves and galls oils during development stages, and varied for fruits oils depending on the ripening stages. Moreover, according to PCA analysis, the best phytoconstituent content and antioxidant activity were attributed to P. atlantica Desf. fruit's crude oils. Also, a strong relationship was found between the antioxidant activity and bioactive phytochemical components, such as tocopherols, carotenoids, and omega‐three fatty acid, which confirmed that P. atlantica Desf. crude oils present a valuable source of natural antioxidant that could be used for pharmaceutical and food industries purposes. 相似文献
29.
Zeinab Hamid Andrew Wadsworth Elham Rezasoltani Sarah Holliday Mohammed Azzouzi Marios Neophytou Anne A. Y. Guilbert Yifan Dong Mark S. Little Subhrangsu Mukherjee Andrew A. Herzing Helen Bristow R. Joseph Kline Dean M. DeLongchamp Artem A. Bakulin James R. Durrant Jenny Nelson Iain McCulloch 《Liver Transplantation》2020,10(8)
The temperature‐dependent aggregation behavior of PffBT4T polymers used in organic solar cells plays a critical role in the formation of a favorable morphology in fullerene‐based devices. However, there is little investigation into the impact of donor/acceptor ratio on morphology tuning, especially for nonfullerene acceptors (NFAs). Herein, the influence of composition on morphology is reported for blends of PffBT4T‐2DT with two NFAs, O‐IDTBR and O‐IDFBR. The monotectic phase behavior inferred from differential scanning calorimetry provides qualitative insight into the interplay between solid–liquid and liquid–liquid demixing. Transient absorption spectroscopy suggests that geminate recombination dominates charge decay and that the decay rate is insensitive to composition, corroborated by negligible changes in open‐circuit voltage. Exciton lifetimes are also insensitive to composition, which is attributed to the signal being dominated by acceptor excitons which are formed and decay in domains of similar size and purity irrespective of composition. A hierarchical morphology is observed, where the composition dependence of size scales and scattering intensity from resonant soft X‐ray scattering (R‐SoXS) is dominated by variations in volume fractions of polymer/polymer‐rich domains. Results suggest an optimal morphology where polymer crystallite size and connectivity are balanced, ensuring a high probability of hole extraction via such domains. 相似文献
30.
Syed Muhammad Hamid Mevlut Citir Erdem Murat Terzi Ismail Cimen Zehra Yildirim Asli Ekin Dogan Begum Kocaturk Umut Inci Onat Moshe Arditi Christian Weber Alexis TraynorKaplan Carsten Schultz Ebru Erbay 《EMBO reports》2020,21(12)
The ER‐bound kinase/endoribonuclease (RNase), inositol‐requiring enzyme‐1 (IRE1), regulates the phylogenetically most conserved arm of the unfolded protein response (UPR). However, the complex biology and pathology regulated by mammalian IRE1 cannot be fully explained by IRE1’s one known, specific RNA target, X box‐binding protein‐1 (XBP1) or the RNA substrates of IRE1‐dependent RNA degradation (RIDD) activity. Investigating other specific substrates of IRE1 kinase and RNase activities may illuminate how it performs these diverse functions in mammalian cells. We report that macrophage IRE1 plays an unprecedented role in regulating phosphatidylinositide‐derived signaling lipid metabolites and has profound impact on the downstream signaling mediated by the mammalian target of rapamycin (mTOR). This cross‐talk between UPR and mTOR pathways occurs through the unconventional maturation of microRNA (miR) 2137 by IRE1’s RNase activity. Furthermore, phosphatidylinositol (3,4,5) phosphate (PI(3,4,5)P3) 5‐phosphatase‐2 (INPPL1) is a direct target of miR‐2137, which controls PI(3,4,5)P3 levels in macrophages. The modulation of cellular PI(3,4,5)P3/PIP2 ratio and anabolic mTOR signaling by the IRE1‐induced miR‐2137 demonstrates how the ER can provide a critical input into cell growth decisions. 相似文献