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5-Butyl-1,4-diphenyl pyrazole and 2-amino-5-chloro pyrimidine acylsulfonamides were developed as potent dual antagonists of Bcl-2 and Bcl-xL. Compounds were optimized for binding to the I88, L92, I95, and F99 pockets normally occupied by pro-apoptotic protein Bim. An X-ray crystal structure confirmed the proposed binding mode. Observation of cytochrome c release from isolated mitochondria in MV-411 cells provides further evidence of target inhibition. Compounds demonstrated submicromolar antiproliferative activity in Bcl-2/Bcl-xL dependent cell lines.  相似文献   
63.
The superfamily Testudinoidea is the most diverse and widely distributed clade of extant turtles. Surprisingly, despite an extensive fossil record, and increasing amount of molecular data available, the temporal origin of this group is still largely unknown. To address this issue, we used a comprehensive molecular dataset to perform phylogenetic and molecular dating analyses, as well as seven fossil constraints to calibrate the ages of the nodes in the phylogeny. The molecular dataset includes the complete mitochondrial genomes of 37 turtle species, including newly sequenced mitochondrial genomes of Phrynops hilarii, Emys orbicularis, Rhinoclemmys punctularia, and Chelonoidis nigra, and four nuclear markers. Our results revealed that the earliest divergences within crown testudinoids occurred around 95.0 Mya, in the early Late Cretaceous, earlier than previously reported, raising new questions about the historical biogeography of this group.  相似文献   
64.
In the broader context of research on the Sicilian Porcellio imbutus-complex, the postmarsupial development of Porcellio siculoccidentalis Viglianisi, Lombardo & Caruso, 1992 was studied in detail. This research was conducted in the laboratory under controlled conditions, allowing us to follow the stages of development, from the formation of the marsupium in ovigerous females until the larval stages and development of the seventh pair of legs. The timing of developmental stages and the morphological modifications of appendages in the postmarsupial manca stages (M I-M III) are described. The manca stage M I had a duration of about one hour. Ovigerous females were collected and reared separately, and the number of parturial molts in the absence of males was counted. The results showed a maximum of four successive parturial molts. Fecundity and fertility were evaluated as the number of eggs and embryos, respectively, inside the marsupium of the ovigerous females. Both parameters were positively correlated with the size of the females. The maximum numbers of eggs and embryos in the marsupium were 113 and 141, respectively. Data describing the total number of postmarsupial mancas released per month indicated that the highest release occurred in April.  相似文献   
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Introduction of the 2,4-difluoro-5-(cyclopropylcarbamoyl)phenylamino group at the C-4 position of the pyrrolo[2,1-f][1,2,4] triazine scaffold led to the discovery of a novel sub-series of inhibitors of VEGFR-2 kinase activity. Subsequent SAR studies on the 1,3,5-oxadiazole ring appended to the C-6 position of this new sub-family of pyrrolotriazines resulted in the identification of low nanomolar inhibitors of VEGFR-2. Antitumor efficacy was observed with compound 37 against L2987 human lung carcinoma xenografts in athymic mice.  相似文献   
68.
Dyscophus antongilii and D. guineti are two morphologically very similar microhylid frogs from Madagascar of uncertain taxonomy. D. antongilii is currently included in Appendix I of the Convention on the International Trade in Endangered Species (CITES) and its exportation is banned completely. In contrast, D. guineti does not receive any legal protection and it is regularly exported. Field data on ecology and behaviour are to a large extent lacking. Here we report on a genetic survey of D. antongilii and D. guineti using nuclear and mitochondrial DNA markers. Sequences of a fragment of 501 bp of the mitochondrial cytochrome b gene from one population of D. antongilii and two populations of D. guineti resulted in a single haplotype network, without haplotype sharing among the populations. However, haplotypes of D.␣guineti were only 1–4 mutational steps from those of D. antongilii, and did not form a clade. The analysis of eight microsatellites newly developed and standardized for D. antongilii revealed an excess of homozygotes and the absence of Hardy–Weinberg equilibrium. The microsatellite data clearly distinguished between D. antongilii and D. guineti, and fixed differences were observed at one locus. Although confirmation of the status of Dyscophus antongilii and D. guineti as separate species requires further data, our study supports the definition of these two taxa as different evolutionary significant units under the adaptive evolutionary conservation concept.  相似文献   
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It has been previously demonstrated that glucagon increased plasma post-heparin lipolytic activity (PHLA) in normal rats, but this was not the case in alloxan diabetic rats. The present work was designed to determine if the administration of exogenous glucagon (0.2 mg i.v.) during suppression of endogenous hormone secretion with somatostatin modifies the plasma post-heparin lipolytic activity in normal rats and the action of such hormone upon monoglyceride hydrolase (MGH) activity. It was found that exogenous glucagon significatively increased PHLA and MGH activity in normal rats after 18-24 hours of starvation. However, both enzymatic activities were not influenced by exogenous glucagon when they were measured during somatostatin administration. Therefore it is believed that the enhancement of these activities observed when somatostatin was not simultaneously given was due to the insulin secretion that follows the glucagon injection.  相似文献   
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