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991.
992.
Global mapping of pharmacological space 总被引:6,自引:0,他引:6
We present the global mapping of pharmacological space by the integration of several vast sources of medicinal chemistry structure-activity relationships (SAR) data. Our comprehensive mapping of pharmacological space enables us to identify confidently the human targets for which chemical tools and drugs have been discovered to date. The integration of SAR data from diverse sources by unique canonical chemical structure, protein sequence and disease indication enables the construction of a ligand-target matrix to explore the global relationships between chemical structure and biological targets. Using the data matrix, we are able to catalog the links between proteins in chemical space as a polypharmacology interaction network. We demonstrate that probabilistic models can be used to predict pharmacology from a large knowledge base. The relationships between proteins, chemical structures and drug-like properties provide a framework for developing a probabilistic approach to drug discovery that can be exploited to increase research productivity. 相似文献
993.
Prolonged rapamycin treatment inhibits mTORC2 assembly and Akt/PKB 总被引:15,自引:0,他引:15
Sarbassov DD Ali SM Sengupta S Sheen JH Hsu PP Bagley AF Markhard AL Sabatini DM 《Molecular cell》2006,22(2):159-168
The drug rapamycin has important uses in oncology, cardiology, and transplantation medicine, but its clinically relevant molecular effects are not understood. When bound to FKBP12, rapamycin interacts with and inhibits the kinase activity of a multiprotein complex composed of mTOR, mLST8, and raptor (mTORC1). The distinct complex of mTOR, mLST8, and rictor (mTORC2) does not interact with FKBP12-rapamycin and is not thought to be rapamycin sensitive. mTORC2 phosphorylates and activates Akt/PKB, a key regulator of cell survival. Here we show that rapamycin inhibits the assembly of mTORC2 and that, in many cell types, prolonged rapamycin treatment reduces the levels of mTORC2 below those needed to maintain Akt/PKB signaling. The proapoptotic and antitumor effects of rapamycin are suppressed in cells expressing an Akt/PKB mutant that is rapamycin resistant. Our work describes an unforeseen mechanism of action for rapamycin that suggests it can be used to inhibit Akt/PKB in certain cell types. 相似文献
994.
995.
Quantitative ethnobotany of two east Timorese cultures 总被引:1,自引:0,他引:1
Sean Collins Xisto Martins Andrew Mitchell Awegechew Teshome John Thor Arnason 《Economic botany》2006,60(4):347-361
This is the first time aspects of the ethnobotany of East Timor have been reported. The medicinal plant traditions of two distinct East Timorese cultures, the Laklei and Idate, were studied and compared using quantitative ethnobotanical methods. A total of 86 medicinal plant species were identified. The medicinal plant traditions of the Laklei and Idate cultures were compared using Trotter and Logan’s (1986) quantitative “informant agreement ratio.” On average, informant consensus was greater in Laklei, suggesting a medicinal plant tradition that is more defined than in Idate, where informants are more likely to use the same medicinal plants when treating the same usage categories. Furthermore, only 11 of the 86 medicinal plant species documented were used by both cultures, of which only six had similar mentions. These findings have important implications for the understanding of ethnobotany as they demonstrate how relatively closely situated cultural groups can have significantly different traditional knowledge systems. 相似文献
996.
The predicted gene models derived from the sea urchin genome were compared to the gene catalogs derived from other completed genomes. The models were categorized by their best match to conserved protein domains. Identification of potential orthologs and assignment of sea urchin gene models to groups of homologous genes was accomplished by BLAST alignment and through the use of a clustering algorithm. For the first time, an overview of the sea urchin genetic toolkit emerges and by extension a more precise view of the features shared among the gene catalogs that characterize the super-clades of animals: metazoans, bilaterians, chordate and non-chordate deuterostomes, ecdysozoan and lophotrochozoan protostomes. About one third of the 40 most prevalent domains in the sea urchin gene models are not as abundant in the other genomes and thus constitute expansions that are specific at least to sea urchins if not to all echinoderms. A number of homologous groups of genes previously restricted to vertebrates have sea urchin representatives thus expanding the deuterostome complement. Obversely, the absence of representatives in the sea urchin confirms a number of chordate specific inventions. The specific complement of genes in the sea urchin genome results largely from minor expansions and contractions of existing families already found in the common metazoan "toolkit" of genes. However, several striking expansions shed light on how the sea urchin lives and develops. 相似文献
997.
998.
Abstract Epiphyas postvittana (Walker) is a serious pest of a number of horticultural crops including grapes in Australia and New Zealand. This study brings together information on the parasitoid complex associated with E. postvittana that previously was fragmented and largely inaccessible. We include species reared during a 3-year study of the parasitoids of E. postvittana in the vineyards of the Coonawarra region, South Australia, material from several Australian agricultural insect collections and records from the literature. An illustrated key is presented for 25 species of parasitoids and hyperparasitoids associated with E. postvittana , along with information on the taxonomy, identification, distribution and biology of each species. Taxa newly recorded from this host are Perilampus sp. (Perilampidae), and six species of Ichneumonidae: Euceros sp., Labium sp., Netelia sp., Plectochorus sp., Temalucha minuta (Morley) and Eriborus epiphyas sp. n., the latter species being described in full. 相似文献
999.
Sinéad Murphy Jerry S. Herman † Graham J. Pierce ‡ Emer Rogan § Andrew C. Kitchener ¶ 《Marine Mammal Science》2006,22(3):573-599
The common dolphin has a widespread distribution and is relatively abundant in the temperate to subtropical waters of the eastern North Atlantic. However, it is not known whether different species, subspecies, or populations occur in this region. We examined 393 common dolphin skulls obtained from both stranded and bycaught individuals collected between 1901 and 2005. The series included skulls of 152 females and 199 males, from animals ranging in body length from 93 to 230 cm and 105 to 244 cm, respectively. The ranges of total body length, skull size, RL/ZGW ratio and maximum upper alveolar (tooth) count of common dolphins in the eastern North Atlantic overlapped with those of both short- ( D. delphis ) and long-beaked ( D. capensis ) species found off the Californian coast. However, in the absence of additional data, the common dolphin in the eastern North Atlantic is regarded here as a large form of Delphinus delphis . Sexual dimorphism and possible sex-linked characters were identified within the sample. Results of the current study indicate some population differentiation within the eastern North Atlantic, with common dolphins off Portugal showing segregation in morphometric characteristics from common dolphins in other areas. 相似文献
1000.
Robert K Browne Hong Li Jessica Seratt Andrew Kouba 《Reproductive biology and endocrinology : RB&E》2006,4(1):3-7
Combinations of progesterone, lutenizing hormone releasing hormone analogue (LHRHa), human chorionic gonadotrophin (hCG),
and the dopamine-2 (DA2) receptor antagonist 1-[1-[4,4-bis(4-Fluorophenyl)butyl]-4-piperidinyl]-1,3-dihydro-2H-benzimidazol-2-one
(Pimozide; Orap) were tested for improvement of spawning rates, oocyte numbers, fertilization and neurulation rates of the
Fowler toad (Bufo fowleri). Only treatments combined with progesterone produced large numbers of oocytes. The best treatment on oocyte numbers, neurulation
rates, and the number of neurulas was with 5 mg progesterone, 20 mic.g LHRHa, and 0.25 mg Pimozide. Progesterone (5 mg) with
60 mic.g LHRHa gave high spawning rates, oocyte numbers, and fertilization rates but neurulation rates were low. Progesterone
alone in high repeated doses did not result in ovulation. High doses of LHRHa (60 mic.g) with hCG, progesterone, and Pimozide
gave the greatest number of toads spawning, however, they resulted in low oocyte numbers, fertilization and neurulation rates.
A low dose of LHRHa (4 mic.g) with hCG, or hCG alone as a second administration, and progesterone with Pimozide produced few
good quality oocytes. Toads were given normal ovulatory doses of hormones 24 or 48 hrs after their initial dose, but these
resulted in low oocyte numbers followed by poor fertilization. Overall, these results suggest that progesterone with a dose
between 20 mic.g and 60 mic.g of LHRHa may be optimal for the induction of ovulation in these toads. Moreover, Pimozide can
supplement low doses of LHRHa but not replace it. 相似文献