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991.
Quilter J E BO Pearsall DM Sandweiss DH Jones JG Wing ES 《Science (New York, N.Y.)》1991,251(4991):277-283
Studies of food remains from the Preceramic monumental site of E1 Paraíso, Peru (1800 to 1500 B.C.), have shed new light on a debate regarding the relative importance of seafood versus terrestrial resources and the role of cultigens in subsistence economies during the early development of Peruvian civilization. Fish was the primary animal food at the site whereas plant foods consisted of a mixture of cultivated resources (squashes, beans, peppers, and jicama) with an additional reliance on fruits (guava, lucuma, and pacae). Wild plants, especially the roots of sedges and cat-tail, also may have accounted for a substantial part of the diet. Cotton was a chief crop, used in making fishing tackle and the textiles that served as clothing and items of high value and status. As an example of the beginnings of civilization, El Paraíso is a case in which impressive architecture was built on a relatively simple subsistence economy and energy was expended in the production of resources useful in local and regional exchange systems. 相似文献
992.
993.
A new variant of the normal minor component Hb A(2) has been detected in a family that lives in Sphakiá, Crete. Chemical studies of this abnormal hemoglobin, designated Hb A(2) delta Sphakiá, indicates a substitution of the histidyl residue number two of the delta-chain by an arginyl residue. 相似文献
994.
Protection of cattle against rinderpest with vaccinia virus recombinants expressing the HA or F gene 总被引:11,自引:0,他引:11
T Yilma D Hsu L Jones S Owens M Grubman C Mebus M Yamanaka B Dale 《Science (New York, N.Y.)》1988,242(4881):1058-1061
Rinderpest is a highly contagious ruminant viral disease manifested by a rapid course and greater than 90% mortality. Infectious vaccinia virus recombinants were constructed that express either the hemagglutinin or the fusion gene of rinderpest virus. All cattle vaccinated with either recombinant or with the combined recombinants produced neutralizing antibodies against rinderpest virus and were protected against the disease when challenged with more than 1000 times the lethal dose of the virus. 相似文献
995.
13-Methylhentriacontane has been identified in the feces and larvae of the corn earworm, Heliothis zea (Boddie), as the major constituent that triggers the short-range host-seeking response of the parasite Microplitis croceipes (Cresson). This chemical, the first found that mediates the complex host-parasite relation, could upgrade present efforts to use parasites for insect control. Bioassay of closely related compounds indicated that the structural requirements for activity are remarkably specific. 相似文献
996.
997.
Jones T Ehardt CL Butynski TM Davenport TR Mpunga NE Machaga SJ De Luca DW 《Science (New York, N.Y.)》2005,308(5725):1161-1164
A distinct species of mangabey was independently found at two sites 370 kilometers apart in southern Tanzania (Mount Rungwe and Livingstone in the Southern Highlands and Ndundulu in the Udzungwa Mountains). This new species is described here and given the name "highland mangabey" Lophocebus kipunji sp. nov. We place this monkey in Lophocebus, because it possesses noncontrasting black eyelids and is arboreal. L. kipunji is distinguished from other mangabeys by the color of its pelage; long, upright crest; off-white tail and ventrum; and loud call. This find has implications for primate evolution, African biogeography, and forest conservation. 相似文献
998.
999.
Tournier C Hess P Yang DD Xu J Turner TK Nimnual A Bar-Sagi D Jones SN Flavell RA Davis RJ 《Science (New York, N.Y.)》2000,288(5467):870-874
The c-Jun NH2-terminal kinase (JNK) is activated when cells are exposed to ultraviolet (UV) radiation. However, the functional consequence of JNK activation in UV-irradiated cells has not been established. It is shown here that JNK is required for UV-induced apoptosis in primary murine embryonic fibroblasts. Fibroblasts with simultaneous targeted disruptions of all the functional Jnk genes were protected against UV-stimulated apoptosis. The absence of JNK caused a defect in the mitochondrial death signaling pathway, including the failure to release cytochrome c. These data indicate that mitochondria are influenced by proapoptotic signal transduction through the JNK pathway. 相似文献
1000.
A new hemoglobin (Hb), Portland 1, has been found in a newborn infant having multiple congenital anomalies and complex autosomal chromosomal mosaicism. The new hemoglobin has a unique tetrameric structure (molecular weight, 66,000) composed of two pairs of different types of chains, neither of which is alpha, gamma(2)x(2). The x-chain of Hb Portland 1 may be a new type of hemoglobin chain, but the available evidence suggests that it may be identical with the epsilon chain. We suggest that Hb Portland 1 is an embryonic hemoglobin that persisted until after birth in relatively large amounts in this patient. 相似文献