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101.
Working on histologic sections 7 microns thick in the equatorial part of male rat adrenal cortex, we found two high mitotic activity periods. The first one stays at midnight and shows an average number of 42 mitoses per section; the second one occurs at 5 a.m. with an average number of mitoses of 70,1 per section. If we except these particular points, the mitotic activity is low, the average number of mitoses being 13,2 per section.  相似文献   
102.
Added free fatty acids inhibit oxidation of glycerol 3-phosphate, succinate and NADH in brown-adipose tissue mitochondria from 10-day-old rats. The most pronounced is the inhibitory effect of glycerol 3-phosphate cytochrome c reductase (GP-cyto. c reductase). Contrary to other reductases, GP-cyto. c reductase activity of freshly isolated mitochondria is already inhibited by the fraction of endogenous free fatty acids. Both added and endogenous free fatty acids inhibition of GP-cyto. c reductase is fully reversible by the removal of free fatty acids by bovine serum albumine treatment. The inhibition of GP-cyto. c reductase is of strictly non-competitive type. The most inhibitory are unsaturated long-chain free fatty acids-oleic and linoleic acid. Results are discussed with regards to the regulatory importance of free fatty acids in brown-adiposetissue during intensive non-shivering thermogenesis.  相似文献   
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The situation of mitoses in the adrenal glands of the rat has been studied by measuring the distance between each of them (3,061 in the whole) at the surface. The curve of their distribution, logarithmic-normal type, shows that they are the most numerous in germinative zone classically described, but that they appear down to the depth of inner fascicula.  相似文献   
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Pustjens  T. F. S.  Streukens  B.  Vainer  J.  Gho  B.  Ruiters  A. W.  Stein  M.  Ilhan  M.  Veenstra  L.  Theunissen  R.  Bekkers  S. C. A. M.  van’t Hof  A. W. J.  Rasoul  S. 《Netherlands heart journal》2020,28(2):75-80
Netherlands Heart Journal - To compare ischaemia-driven complete coronary revascularisation by percutaneous coronary intervention (PCI) with usual care in patients with non-ST-elevation myocardial...  相似文献   
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Rechargeable batteries based on MnO2 cathodes, able to operate in mild aqueous electrolytes, have attracted attention due to their appealing features for the design of low‐cost stationary energy storage devices. However, the charge/discharge mechanism of MnO2 in such media is still a matter of debate. Here, an in‐depth quantitative spectroelectrochemical analysis of MnO2 thin‐films provides a set of unrivaled mechanistic insights. A major finding is that charge storage occurs through the reversible two‐electron faradaic conversion of MnO2 into Mn2+ in the presence of a wide range of weak Brønsted acids, including the [Zn(H2O)6]2+ or [Mn(H2O)6]2+ complexes present in aqueous Zn/MnO2 batteries. Furthermore, it is shown that buffered electrolytes loaded with Mn2+ are ideal to achieve highly reversible conversion of MnO2 with both high gravimetric capacity and remarkably stable charging/discharging potentials. In the most favorable case, a record gravimetric capacity of 450 mA·h·g?1 is obtained at a high rate of 1.6 A·g?1, with a Coulombic efficiency close to 100% and a MnO2 utilization of 84%. Overall, the present results challenge the common view on MnO2 the charge storage mechanism in mild aqueous electrolytes and underline the benefit of buffered electrolytes for high‐performance rechargeable aqueous batteries.  相似文献   
110.
Perovskite solar cells (PSC) have shown that under laboratory conditions they can compete with established photovoltaic technologies. However, controlled laboratory measurements usually performed do not fully resemble operational conditions and field testing outdoors, with day‐night cycles, changing irradiance and temperature. In this contribution, the performance of PSCs in the rooftop field test, exposed to real weather conditions is evaluated. The 1 cm2 single‐junction devices, with an initial average power conversion efficiency of 18.5% are tracked outdoors in maximum power point over several weeks. In parallel, irradiance and air temperature are recorded, allowing us to correlate outside factors with generated power. To get more insight into outdoor device performance, a comprehensive set of laboratory measurements under different light intensities (10% to 120% of AM1.5) and temperatures is performed. From these results, a low power temperature coefficient of ?0.17% K?1 is extracted in the temperature range between 25 and 85 °C. By incorporating these temperature‐ and light‐dependent PV parameters into the energy yield model, it is possible to correctly predict the generated energy of the devices, thus validating the energy yield model. In addition, degradation of the tested devices can be tracked precisely from the difference between measured and modelled power.  相似文献   
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