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Summary A substance immunologically related to mammalian insulin was demonstrated by immunofluorescence in one of five types of neurosecretory cells in the protocerebrum of the European corn borer, Ostrinia nubilalis. This A2 cell type contains a secretory material stainable with paraldehyde fuchsin.E.R.A. CNRS n° 850  相似文献   
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The spermicidal efficacy of synthetic peptides, dermaseptin (DS1) and (DS4), was studied under in vitro conditions using human spermatozoa. The data showed that sperm motility was inhibited with various concentrations of dermaseptins at different intervals ranging from 2 to 240 min. The effective 100% inhibitory concentration (EC100) of DS4 sperm immobilization assay was equal to 50 mg/ml at 30 min, while the EC 100 of DS1 was equal to 100 mg/ml. The presence of 0.1% of chelating agent, EDTA, reduced the EC100 of DS4 to 5 mg/ml, while less than a twofold enhancement in DS 1 activity was observed in combination with EDTA. The action of dermaseptins on sperm motility was observed to be dose-dependent. Addition of pentoxifylline, which is known to enhance sperm motility, and Ca2+, which is a key element for sperm movement, did not prevent the spermicidal action of dermaseptins.  相似文献   
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The combination of seminal vesicle cyst and homolateral renal agenesis is a rare congenital anomaly. However, this anomaly is diagnosed more frequently due to progress in medical imaging. The authors report three cases of seminal vesicle cyst associated with ipsilateral renal agenesis in two cases and ectopic ureter in one case. All cases presented nonspecific clinical symptoms. The diagnosis was suspected on imaging (ultrasound and computed tomography). Treatment was surgical in two cases and endoscopie in one case. The authors review the literature on the aetiology and pathogenesis of seminal vesicle cyst, its association with homolateral renal agenesis and diagnostic and therapeutic methods.  相似文献   
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The aim of this work was to investigate the cytotoxic effect of the essential oil of dried leaves of Lippia citriodora (H.B. & K.) harvested in different regions of Morocco. This effect was evaluated against the P815 murine mastocytoma cell line using the MTT assay. Interestingly, this work demonstrated for the first time that these essential oils exhibited a strong cytotoxic activity against the P815 cell line, with IC50 values ranging from 7.75 to 13.25 μg/ml. This cytotoxicity began early and increased in a dose‐ and time‐dependent manner. The chemical profile of these essential oils was analyzed by gas chromatography coupled to mass spectrometry. Importantly, the difference in terms of major components’ contents was not significant suggesting probably that the differential cytotoxicity between these essential oils could be attributed to the difference in the content of these essential oils in minor compounds, which could interact with each other or with the main molecules. Finally, this study demonstrated for the first time that essential oils of L. citriodora from different regions in Morocco induced apoptosis against P815 tumor cell line.  相似文献   
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DNA methylation is a chemical modification of DNA involved in the regulation of gene expression by controlling the access to the DNA sequence. It is the most stable epigenetic mark and is widely studied for its role in major biological processes. Aberrant DNA methylation is observed in various pathologies, such as cancer. Therefore, there is a great interest in analyzing subtle changes in DNA methylation induced by biological processes or upon drug treatments. Here, we developed an improved methodology based on flow cytometry to measure variations of DNA methylation level in melanoma and leukemia cells. The accuracy of DNA methylation quantification was validated with LC-ESI mass spectrometry analysis. The new protocol was used to detect small variations of cytosine methylation occurring in individual cells during their cell cycle and those induced by the demethylating agent 5-aza-2''-deoxycytidine (5AzadC). Kinetic experiments confirmed that inheritance of DNA methylation occurs efficiently in S phase and revealed a short delay between DNA replication and completion of cytosine methylation. In addition, this study suggests that the uncoupling of 5AzadC effects on DNA demethylation and cell proliferation might be related to the duration of the DNA replication phase.  相似文献   
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A bioassay for juvenile hormone activity in last-stage larvae of Adoxophyes orana M. was developed, in order to compare the morphogenetic activity of this compound and its analogues. After topical application, the activity of two non-sesquiterpenoids possessing the methylene-dioxyphenyl group greatly exceeded that of all other compounds tested, including three sesquiterpenoids and one non-sesquiterpenoid in which the methylenedioxy group was replaced by chlorine.
Zusammenfassung Er wurde ein Bio-Versuch zur Feststellung der Juvenilhormonaktivität im letzten Larvenstadium von Adoxophyes orana entwickelt, um die morphogenetische Aktivität dieser Verbindung und ihrer Analoge vergleichen zu können. Nach topischer Applikation übertraf die Aktivität zweier Non-Sesquiterpenoide, die eine Methylendioxyphenyl-Gruppe besitzen, die aller anderen geprüften Substanzen bei weitem, einschließlich dreier Sesquiterpenoide und eines Non-Sesquiterpenoids, deren Methylendioxy-Gruppe durch Chlor ersetzt war.
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150.

Due to the increasing use of radioactive sources, new challenges appear for the protection of humans and the environment against ionizing radiation. Thus, organizations handling these sources must be endowed with plans how to react in case of any radiological emergency situations. Monte Carlo simulations are among the most widely employed methods used for the management and reconstruction of radiological incidents and accidents. In this work, results of a Monte Carlo simulation study with the Geant4 simulation toolkit using a digital anthropomorphic phantom are reported. The investigated scenario included an emergency intervention carried out inside the ionization cell of the National Institute of Agronomic Research (NIAR) of Tangier/Morocco, which houses a 60Co gamma irradiator. In this scenario, a radiological incident was assumed where the source cage of the gamma irradiator is stuck in the guide tube and not completely inserted into its storage container. The objective of this work was to design a radiation shield to protect an operator during the emergency intervention and make sure that any radiation exposure is below the recommended dose limits, taking into account the date of occurrence (which determines the activity of the source at the time of the emergency situation) of the accident and economic aspects of shielding design. In this work, the maximum time available for the operator to accomplish the operation intervention while remaining protected is calculated. The results obtained show that the shielding prototype developed gives the operator a time between 3 and 300 s, depending on shielding design. It is concluded that shielding of the type investigated in the present study will allow any facility to manage the assumed emergency scenario, should it occur.

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