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21.
Herein we studied the preparation of different thiazoles via the reaction of 2-(3,4-dimethoxybenzylidene)hydrazine-1-carbothioamide (1) with hydrazonoyl halides under base-catalyzed conditions. The reactions proceed through nucleophilic substitution attack at the halogen atom of the hydrazonoyl halides by the thiol nucleophile to form an S-alkylated intermediate. The latter intermediate undergoes cyclization by the loss of water to afford the final products. The structures of the azo compounds were confirmed by FTIR, MS, NMR, and elemental analyses. Indeed, the newly synthesized azo compounds were estimated for their potential anticancer activities by an MTT assay against different human cancer cells, such as lung adenocarcinoma (A549) and colorectal adenocarcinoma (DLD-1). The caspase-3 levels were also estimated using Western blotting and the dual staining technique to evaluate the potency of the titled compounds to promote apoptosis.  相似文献   
22.
Carbonic anhydrases (EC 4.2.1.1) catalyse the reversible hydration of CO2 into bicarbonate and protons. As a hypoxia-sensitive and tumour-associated isoform, isoform CA IX, is significantly overexpressed in various malignancies, being a validated target for new anticancer/antimetastatic drugs. A multitude of studies has shown that CA IX inhibition decreases cancer cell proliferation and metastasis through pHe/pHi modulation and enhancement of ferroptosis among others. Numerous studies demonstrated increased efficacy of cytotoxic drugs combined with CA inhibitors (CAIs) in various cancer types. We tested the inhibitory effect of boric acid (BA), an inorganic Lewis acid, on CA IX as well as other isoforms (CA I, II, and XII). BA acted as a millimolar in vitro CAI, decreased proliferation of two cancer cell lines, although not strong correlations between the in vitro inhibition and in vivo effects were observed. The mechanism of antiproliferative action of BA should be investigated in more detail.  相似文献   
23.
Summary The antibacterial effect of negapillin in combination with other antibiotics and sulfa drugs was studied using Gram+ve and Gram-ve bacteria as test organisms. Subsequently, various proportions of negapillin in combination with the antibiotics and the sulfa drugs were examined to determine the optimum proportions which exert maximum inhibitory effects on the bacterial growth. Mixtures of these antibiotics with negapillin were found more superior not only as antimicrobial agents but also for having comparatively low toxicity.  相似文献   
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Annual variations in plasma testosterone and cortisol levels were determined in male wild rabbits caught monthly in their natural biotope (Zembra island). For comparison, a group of warrens was hold in semi-captivity close to Tunis. In both conditions plasma testosterone concentrations were low from January to September and peak values were observed in October. Captive warrens exhibited a clear cut annual rhythm in plasma cortisol levels also and ether stress resulted in a very large increase of cortisolemia. In rabbits caught in ther habitat however, cortisol concentrations were always extremely high throughout the year, probably due to stressing conditions. Interestingly, wild rabbits of Zembra island appear to subsist from a very remote past without any contact with other strains. As to Zembra, it is a hardly get-at-able, uninhabited island which is a part of a strictly protected natural reserve and constitutes a fairly useful and valuable ecosystem.  相似文献   
26.
Differences in the composition and amount of proteins synthesized in the cell culture and leaves of field plants Serratula coronata have been shown. They proceed from differences in intensity of synthesis of secondary metabolites, ecdysteroids, whose content in the cell culture is considerably lower.  相似文献   
27.
Ecological restoration is considered to play an important role in mitigating climate change, protecting biodiversity, and preventing environmental degradation. Yet, there are often multiple perspectives on what outcomes restoration should be aiming to achieve, and how we should get to that point. In this study we interview a range of policymakers, academics, and non‐governmental organization (NGO) representatives to explore the range of perspectives on the restoration of Indonesia's tropical peatlands—key global ecosystems that have undergone large‐scale degradation. Thematic analysis suggests that participants agreed about the importance of restoration, but had differing opinions on how effective restoration activities to date have been and what a restored peatland landscape should look like. These results exemplify how ecological restoration can mean different things to different people, but also highlight important areas of consensus for moving forward with peatland restoration strategies.  相似文献   
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This paper represents an attempt to investigate the mating behaviour of Symmorphus allobrogus, explaining the willingness of male to mount and copulate. The male displays including mode and frequency of antennation and position while copulating, the displays further comprises of intensity and frequency of rejecting behaviour. The presence of the male’s copulatory and postcopulatory courtship studies, understands the maintenance of monandry. The wasp has numerous secondary sexual characters, and the mating behaviour follows a phyletic and the specific sexual mating characters in context of sexual selection. The duration of mating phases and the number of male antennation series during precopulatory, copulatory and postcopulatory phases of mounting, differs significantly. Mating success depends mostly on the activities of male in the premounting phase and the behaviour of both sexes has a roughly equal importance for it in precopulatory phase. While during copulation, activity of male has little influence on its duration; however, behaviour of female has crucial effect, inducing its earlier termination.  相似文献   
30.
International Journal of Peptide Research and Therapeutics - The original version of the article unfortunately contained a typo in co-author name.  相似文献   
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