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1.
Ajania semnanensis (Compositae: Anthemideae), a new species of Ajania from northeast of Iran, Semnan province, is described and illustrated. Ajania semnanensis is a suffruticose perennial growing on rocky and stony slopes of mountains at altitudes of 1500–2800 m a.s.l. Karyological and micromorphological data of the pollen and achenes, as well as a distribution map for the species are provided. The cytotype of the species was found to be diploid (2n = 2x = 18) based on x = 9. The karyotype formula is 2n = 2x = 4M + 6m + 6sm + 2st. Pollen grains of A. semnanensis are prolate‐spheroidal (P/E = 1.1), 3‐zonocolporate and echinate (Anthemis type). The achenes of A. semnanensis are obovate, 1.0–1.5 × 0.5–0.6 mm, light brown, with 4–6 fine and inconspicuous ribs, glabrous, without pappus and with a subbasal carpopodium. The IUCN status of the new species is suggested to be ‘Least Concern’ (LC).  相似文献   
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Molecular Biology Reports - Coronary artery disease (CAD), is the leading cause of mortality and morbidity worldwide. Tenascin-C (TNC) with high expression levels in inflammatory and cardiovascular...  相似文献   
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Neurochemical Research - Hippocampal oxidative stress has a vital role in the pathophysiology of Alzheimer’s disease (AD)-associated behavioral deficits. Ecdysterone (Ecdy), a natural product...  相似文献   
4.
Kahalalide F (KF) and the regioisomer isoKF are novel anticancer drugs of marine origin and currently under clinical investigation. Here we report the synthesis of two new KF analogs with significant in vitro and in vivo antifungal and antitumor activities. The primary amine hydrogen of ornithine in KF has been replaced with 4-fluoro-3-methylbenzyl and morpholin-4-yl-benzyl via reductive N-alkylation. The TGI of these analogs using the NCI-60 cell line screening revealed promising results when compared to paclitaxel. The result of in vivo hollow fiber and animal toxicity assays are presented.  相似文献   
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Foehn-like extreme hot and dry wind conditions (34°C, >2.5 kPa vapor pressure deficit, and 7 m s−1) strongly affect grain quality in rice (Oryza sativa L.). This is a current concern because of the increasing frequency and intensity of combined heat and water-deficit stress under climate change. Foehn-induced dry wind conditions during the grain-filling stage increase ring-shaped chalkiness as a result of spatiotemporal reduction in starch accumulation in the endosperm, but kernel growth is sometimes maintained by osmotic adjustment. Here, we assess the effects of dry wind on chalky ring formation in environmentally controlled growth chambers. Our results showed that hot and dry wind conditions that lasted for >24 h dramatically increased chalky ring formation. Hot and dry wind conditions temporarily reduced panicle water potential to –0.65 MPa; however, kernel growth was maintained by osmotic adjustment at control levels with increased transport of assimilate to the growing kernels. Dynamic tracer analysis with a nano-electrospray-ionization Orbitrap mass spectrometer and quantitative polymerase chain reaction analysis revealed that starch degradation was negligible in the short-term treatment. Overall expression of starch synthesis-related genes was found to be down-regulated at moderately low water potential. Because the events observed at low water potential preceded the packing of starch granules in cells, we concluded that reduced rates of starch biosynthesis play a central role in the events of cellular metabolism that are altered at osmotic adjustment, which leads to chalky ring formation under short-term hot and dry wind conditions.  相似文献   
7.
Photoactive perovskite semiconductors are highly tunable, with numerous inorganic and organic cations readily incorporated to modify optoelectronic properties. However, despite the importance of device reliability and long service lifetimes, the effects of various cations on the mechanical properties of perovskites are largely overlooked. In this study, the cohesion energy of perovskites containing various cation combinations of methylammonium, formamidinium, cesium, butylammonium, and 5‐aminovaleric acid is reported. A trade‐off is observed between the mechanical integrity and the efficiency of perovskite devices. High efficiency devices exhibit decreased cohesion, which is attributed to reduced grain sizes with the inclusion of additional cations and PbI2 additives. Microindentation hardness testing is performed to estimate the fracture toughness of single‐crystal perovskite, and the results indicated perovskites are inherently fragile, even in the absence of grain boundaries and defects. The devices found to have the highest fracture energies are perovskites infiltrated into a porous TiO2/ZrO2/C triple layer, which provide extrinsic reinforcement and shielding for enhanced mechanical and chemical stability.  相似文献   
8.
Heterocyclic compounds such as quinazolinones have variety of biological and pharmacological properties (anticancer, antiinflammatory, antimicrobial, antimalaria, etc.). Effects of two new quinazolinones viz., 4(3H)-quinazolinone-2-propyl-2-phenylethyl (QPPE) and 4(3H)quinazolinone-2-ethyl-2-phenylethyl (QEPE) were investigated on Balb/C mice embryos livers-the major organ of metabolism and detoxification of drugs and toxins. Histological and pathological studies demonstrated QPPE and QEPE as producers of toxic metabolites after biotransformation, creating necrosis, fatty changes, increase in the number of band cells, hepatocytes' diameters and alkaline phosphatase, in addition to sinusoid dilation, hemorrhages and hyperemia. Transmission electron micrographs showed lipid droplets in hepatocytes' cytoplasm, necrosis, vacuolization, cytoplasm disintegration, disfigured and swollen mitochondria, irregular and abnormal nuclei, nuclei with heterochromatin, condensed chromatins, myelin figures and autophages in injured hepatocytes. In conclusion, QPPE and QEPE make toxic components after biotransformation injuring membranes and creating inflammatory reactions. They also disturb metabolism of lipids pathways and cause the appearances of lipid droplets in hepatocytes.  相似文献   
9.
Legionella pneumophila peptidoglycan-associated lipoprotein (PAL) protein is an extremely conserved antigen among Legionella species. In this study, rabbit and rat anti-PAL immunoglobulin G antibodies were produced by immunization with purified, recombinant PAL (r-PAL) protein of L. pneumophila serogroup 1 and used as capture and detection antibodies in the PAL antigen-based enzyme-linked immunosorbent assay (ELISA) to detect urinary PAL antigen. Urine samples were obtained from rats experimentally infected with L. pneumophila serogroup 1. The PAL antigen was measured in urine samples of 40 infected and 40 uninfected rats. After choosing the cut-off value of 0.192, the sensitivity and specificity of the PAL antigen-based ELISA were 87.5 and 97.5 %, respectively. The results obtained by PAL antigen base ELISA were compared with those obtained by Biotest. The PAL antigen was detected efficiently by both of the assays and all of the control human urine samples were negative by the ELISA test. The PAL antigen-based ELISA assay was relatively simple to perform, precise, highly sensitive and specific, and reproducible. Based on our data the PAL antigen-based ELISA described here is the first indirect sandwich ELISA for urinary antigen detection which could easily be applied for diagnosis of Legionnaires disease.  相似文献   
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