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991.
Measurements have been made of the ratios of chlorine-36 to chlorine in five halite samples from Searles Lake sediments, previously dated by carbon-14, thorium-230, and magnetostratigraphic techniques. The ages calculated from the chlorine ratios are generally concordant with those from the other methods, implying the constancy of the chlorine input ratio over the last million years. 相似文献
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993.
Induction of CD4+ human cytolytic T cells specific for HIV-infected cells by a gp160 subunit vaccine 总被引:25,自引:0,他引:25
R J Orentas J E Hildreth E Obah M Polydefkis G E Smith M L Clements R F Siliciano 《Science (New York, N.Y.)》1990,248(4960):1234-1237
Cytolytic T lymphocyte (CTL) responses were evaluated in humans immunized with recombinant human immunodeficiency virus type 1 (HIV) envelope glycoprotein gp160. Some vaccinees had gp160-specific CTLs that were shown by cloning to be CD4+. Although induced by exogenous antigen, most gp160-specific CTL clones also recognized gp160 synthesized endogenously in target cells. These clones lysed autologous CD4+ T lymphoblasts infected with HIV. Of particular interest were certain vaccine-induced clones that lysed HIV-infected cells, recognized gp160 from diverse HIV isolates, and did not participate in "innocent bystander" killing of noninfected CD4+ T cells that had bound gp120. 相似文献
994.
Gelfand MJ Raver JL Nishii L Leslie LM Lun J Lim BC Duan L Almaliach A Ang S Arnadottir J Aycan Z Boehnke K Boski P Cabecinhas R Chan D Chhokar J D'Amato A Ferrer M Fischlmayr IC Fischer R Fülöp M Georgas J Kashima ES Kashima Y Kim K Lempereur A Marquez P Othman R Overlaet B Panagiotopoulou P Peltzer K Perez-Florizno LR Ponomarenko L Realo A Schei V Schmitt M Smith PB Soomro N Szabo E Taveesin N Toyama M Van de Vliert E Vohra N Ward C Yamaguchi S 《Science (New York, N.Y.)》2011,332(6033):1100-1104
With data from 33 nations, we illustrate the differences between cultures that are tight (have many strong norms and a low tolerance of deviant behavior) versus loose (have weak social norms and a high tolerance of deviant behavior). Tightness-looseness is part of a complex, loosely integrated multilevel system that comprises distal ecological and historical threats (e.g., high population density, resource scarcity, a history of territorial conflict, and disease and environmental threats), broad versus narrow socialization in societal institutions (e.g., autocracy, media regulations), the strength of everyday recurring situations, and micro-level psychological affordances (e.g., prevention self-guides, high regulatory strength, need for structure). This research advances knowledge that can foster cross-cultural understanding in a world of increasing global interdependence and has implications for modeling cultural change. 相似文献
995.
Green ML Smith JD Kass PH 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(10):1101-1105
This study retrospectively evaluated long-term outcomes of 18 cats diagnosed with small intestinal adenocarcinoma, based on surgical versus non-surgical treatment and the presence or absence of metastasis at the time of surgery. Ten cats had surgery and histopathologic confirmation of adenocarcinoma and 8 cats did not have surgery but had cytologic diagnosis of adenocarcinoma. Median survival of cats with adenocarcinoma that underwent surgical excision was 365 days and 22 days for those with suspected adenocarcinoma that did not undergo surgery (P = 0.019). Median survival of cats was 843 days for those without evidence of metastatic disease at the time of surgery and 358 days for those that had (P = 0.25). In conclusion, surgical excision is beneficial in the treatment of small intestinal adenocarcinoma in the cat, including those patients with metastasis, and may result in a significantly longer survival time compared with patients which do not have their mass surgically excised. 相似文献
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Smith RJ 《Science (New York, N.Y.)》1985,228(4701):831-832
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