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排序方式: 共有88条查询结果,搜索用时 31 毫秒
41.
Ahuja SK Aiuti F Berkhout B Biberfeld P Burton DR Colizzi V Deeks SG Desrosiers RC Dierich MP Doms RW Emerman M Gallo RC Girard M Greene WC Hoxie JA Hunter E Klein G Korber B Kuritzkes DR Lederman MM Malim MH Marx PA McCune JM McMichael A Miller C Miller V Montagnier L Montefiori DC Moore JP Nixon DF Overbaugh J Pauza CD Richman DD Saag MS Sattentau Q Schooley RT Shattock R Shaw GM Stevenson M Trkola A Wainberg MA Weiss RA Wolinsky S Zack JA 《Science (New York, N.Y.)》2006,314(5801):924-925
42.
Vinceti M Pellacani G Malagoli C Bassissi S Sieri S Bonvicini F Krogh V Seidenari S 《Public health nutrition》2005,8(8):1307-1314
OBJECTIVE: We aimed at examining the association between dietary constituents and risk of cutaneous melanoma. DESIGN: In an area of northern Italy we recruited 59 newly diagnosed melanoma patients and 59 age- and sex-matched population controls, to whom we administered a validated semi-quantitative food-frequency questionnaire. RESULTS: We found an excess risk of melanoma in subjects with a higher energy-adjusted intake of total polyunsaturated fatty acids and, in particular, of linoleic acid (relative risk = 2.16 for intake in the highest tertile compared with the lowest tertile, P for linear trend = 0.061). Conversely, disease risk was inversely associated with the consumption of soluble carbohydrates (relative risk = 0.34 for intake in the upper vs. the lowest tertile adjusting for total energy intake, P for linear trend = 0.046). No other dietary factors, including alcohol, vitamins and trace elements, correlated with melanoma risk. The association of melanoma risk with linoleic acid and soluble carbohydrates intakes was further strengthened in multivariate analysis, and when analysis was limited to females. CONCLUSIONS: Overall, these results indicate that an excess energy-adjusted intake of linoleic acid and a lower consumption of soluble carbohydrates may increase melanoma risk. 相似文献
43.
Fusco Valeria Pasciuta Vittorio Lumia Valentina Matere Antonio Battaglia Valerio Bertinelli Giorgia Sansone Domenico Brunetti Angela Pilotti Massimo 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(1):71-96
European Journal of Plant Pathology - Lethal wilting was observed on young olive trees cv Favolosa in a grove in central Italy. White mycelial strands wrapped the basal portion of the stems that... 相似文献
44.
Téglás E Vul E Girotto V Gonzalez M Tenenbaum JB Bonatti LL 《Science (New York, N.Y.)》2011,332(6033):1054-1059
Many organisms can predict future events from the statistics of past experience, but humans also excel at making predictions by pure reasoning: integrating multiple sources of information, guided by abstract knowledge, to form rational expectations about novel situations, never directly experienced. Here, we show that this reasoning is surprisingly rich, powerful, and coherent even in preverbal infants. When 12-month-old infants view complex displays of multiple moving objects, they form time-varying expectations about future events that are a systematic and rational function of several stimulus variables. Infants' looking times are consistent with a Bayesian ideal observer embodying abstract principles of object motion. The model explains infants' statistical expectations and classic qualitative findings about object cognition in younger babies, not originally viewed as probabilistic inferences. 相似文献
45.
Formisano V Atreya S Encrenaz T Ignatiev N Giuranna M 《Science (New York, N.Y.)》2004,306(5702):1758-1761
We report a detection of methane in the martian atmosphere by the Planetary Fourier Spectrometer onboard the Mars Express spacecraft. The global average methane mixing ratio is found to be 10 +/- 5 parts per billion by volume (ppbv). However, the mixing ratio varies between 0 and 30 ppbv over the planet. The source of methane could be either biogenic or nonbiogenic, including past or present subsurface microorganisms, hydrothermal activity, or cometary impacts. 相似文献
46.
47.
Luciana Rossi Alessia Di Giancamillo Serena Reggi Cinzia Domeneghini Antonella Baldi Vittorio Sala Vittorio Dell'Orto Annelies Coddens Eric Cox Corrado Fogher 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(3):263-270
Verocytotoxic Escherichia (E.) coli strains are responsible for swine oedema disease, which is an enterotoxaemia that causes economic losses in the pig industry. The production of a vaccine for oral administration in transgenic seeds could be an efficient system to stimulate local immunity. This study was conducted to transform tobacco plants for the seed-specific expression of antigenic proteins from a porcine verocytotoxic E. coli strain. Parameters related to an immunological response and possible adverse effects on the oral administration of obtained tobacco seeds were evaluated in a mouse model. Tobacco was transformed via Agrobacteium tumefaciens with chimeric constructs containing structural parts of the major subunit FedA of the F18 adhesive fimbriae and VT2e B-subunit genes under control of a seed specific GLOB promoter. We showed that the foreign Vt2e-B and F18 genes were stably accumulated in storage tissue by the immunostaining method. In addition, Balb-C mice receiving transgenic tobacco seeds via the oral route showed a significant increase in IgA-positive plasma cell presence in tunica propria when compared to the control group with no observed adverse effects. Our findings encourage future studies focusing on swine for evaluation of the protective effects of transformed tobacco seeds against E. coli infection. 相似文献
48.
Dynamics of ascocarp development, ascospore maturation, and dispersal in Erysiphe necator were studied over a 4-year period, from the time of ascocarp formation to the end of the ascosporic season at the end of June in the following spring. Naturally dispersed chasmothecia were collected from mid-August to late November (when leaf fall was complete); the different collections were used to form three to five cohorts of chasmothecia per year, with each cohort containing ascocarps formed in different periods. Chasmothecia were exposed to natural conditions in a vineyard and periodically sampled. Ascocarps were categorized as containing mature or immature ascospores, or as empty; mature ascospores inside chasmothecia were enumerated starting from late February. Ascospore discharge was determined using silicone-coated slides that were placed 3 to 4 cm from sections of the vine trunk holding the chasmothecia. Before complete leaf fall, 34% of the chasmothecia had mature ascospores, 48% had immature ascospores, and 18% were empty; in the same period, the trapped ascospores represented 56% of the total ascospores trapped in an ascosporic season (i.e., from late summer until the next spring or early summer). The number of viable chasmothecia diminished over time; 11 and 5% of chasmothecia had mature ascospores between complete leaf fall and bud break and after bud break, respectively. These ascocarps discharged ≈2 and 42% of the total ascospores, respectively. All the ascocarp cohorts released ascospores in autumn, survived the winter, and discharged viable ascospores in spring; neither ascospore numbers nor their pattern of temporal release was influenced by the time when chasmothecia were collected and exposed in the vineyard. Abundance of mature ascospores in chasmothecia was expressed as a function of degree-days (DD) (base 10°C) accumulated before and after bud break through a Gompertz equation (R2 = 0.92). Based on this equation, 90% of the ascospores were mature when 153 DD (confidence interval, 100 to 210 DD) had accumulated after bud break. Most ascospores were trapped in periods with >2 mm of rain; however, a few ascospores were airborne with <2 mm of rain and, occasionally, in wet periods of ≥3.5 h not initiated by rain. 相似文献
49.
Paola Battilani Silvia FormentiCesare Ramponi Vittorio Rossi 《Journal of Cereal Science》2011,54(3):467-472
The dynamic of water activity (aw) and humidity (h) of maize (Zea mays L.) kernels and their relevance for fumonisin (FUM) accumulation in kernels was studied in 10 commercial hybrids grown in 5 locations of North Italy, in 2007 and 2008. The dynamic of both aw and h in maize kernels was different in diverse hybrids and was accurately described by monomolecular and linear regression, respectively, using degree-days (base 0 °C) accumulated between female flowering and harvest as an independent variable (R2 = 0.61-0.96, depending on the hybrid). FUM contamination at harvest was predicted by using aw as an independent variable in a logistic regression which provided 67% of correct prediction of cases with FUM ≥ 4000 μg/kg of kernel; accuracy of prediction increased to 72% by using both aw and ECB severity as independent variables. The use of h as independent variable provided 71% correct predictions, but specific correction factors were necessary for each hybrid. Results showed that “slow dry down” hybrids were more prone to FUM accumulation, irrespective of their season length. The identification of factors able to drive aw dynamic in maize kernels and their genetic bases may then provide a crucial contribution in breeding maize for resistance to FUM contamination. 相似文献
50.