摘要：
Treatment of potato (Solanum tuberosum L.) with chlorocholine chloride (CCC) applied twice as a foliar spray 25 and 30 days after planting has shown to decrease shoot and stolon growth but increase tuber yield. However, the regulatory role of CCC on translocation of recently fixed photoassimilates into different parts of potato plants has not been fully illustrated. In this study, C-14-isotope labelling technique was used to estimate the photosynthetic capacity and photoassimilate partitioning among leaves, stems, roots + stolons, and tubers of potted potatoes treated with 1.5 g l(-1) CCC. CCC treatment significantly increased tuber dry mass but reduced leaf dry mass. CCC-treated leaves had significantly higher chlorophyll and carotenoid contents and assimilated 22.0% more (CO2)-C-14 per leaf dry mass than the controls. Compared with the control, CCC treatment reduced the translocation of C-14-photoassimilates into leaves, steins and roots + stolons but increased that into tubers. CCC-treated leaves exported 14.6% more C-14-photoassimilates into other parts of the plants. In addition, CCC treatment reduced C-14-Soluble sugarand C-14-starch accumulation in leaves and stems but enhanced them in tubers and roots + stolons. Collectively, the results indicate that CCC treatment significantly improves the photosynthetic capacity of potato leaves and promotes photoassimilates partitioning into tubers thereby enhancing tuber growth. (C) 2008 Elsevier B.V. All rights reserved.
关键词：
Human immunoglobulin E (IgE);Methylene blue (MB);Gold nanoparticles (GNPs)
摘要：
A label-free electrochemical immunosensor for the detection of protein analytes without redox-active centers is for the first time developed based on the combination of gold nanoparticles and the mediated charge transport through the multilayer films that is related to an electrocatalytic process. Given the low detection limit, high sensitivity and selectivity, the success achieved here seems plausibly to serve as a significant step toward the development of versatile label-free immunoassay.
摘要：
Background: Studies have demonstrated that lead exposure can result in cognitive dysfunction and behavior disorders. However, lead exposure impairments vary under different experimental conditions. Objective: To detect changes in spatial learning and memory following low-level lead exposure in rats, in Morris water maze test under the same experimental condition used to analyze lead exposure effects on various memory types and learning processes. Design and setting: The experiment was conducted at the Animal Laboratory, Institute of Psychology, Chinese Academy of Science between February 2005 and March 2006. One-way analysis of variance (ANOVA) and behavioral observations were performed. Materials: Sixteen male, healthy, adult, Sprague Dawley rats were randomized into normal control and lead exposure groups (n = 8). Methods: Rats in the normal control group were fed distilled water, and those in the lead exposure group were fed 250 mL of 0.05% lead acetate once per day. At day 28, all rats performed the Morris water maze test, consisting of four phases: space navigation, probe test, working memory test, and visual cue test. Main outcome measures: Place navigation in the Morris water maze was used to evaluate spatial learning and memory, probe trials for spatial reference memory, working memory test for spatial working memory, and visual cue test for non-spatial cognitive function, Perkin-Elmer Model 300 Atomic Absorption Spectrometer was utilized to determine blood lead levels in rats. Results: (1) In the working memory test, the time to reach the platform remained unchanged between the control and lead exposure groups (F(1, 1) = 0.007, P = 0.935). A visible decrease in escape latencies was observed in each group (P= 0.028). However, there was no significant difference between the two groups (F(1, 1) = 1.869, P = 0. 193). The working memory probe test demonstrated no change between the two groups in the time spent in the target quadrant during the working memory probe test (F(1, 1) = 1.869, P = 0.193). However, by day 4, differences were observed in the working memory test (P < 0.01). (2) Multivariate repetitive measure and ANOVA in place navigation presented no significant difference between the two groups (F(1, 11) = 0.579, P = 0.459). (3) Spatial probe test demonstrated that the time to reach the platform was significantly different between the two groups (F(1, 1) = 4.587, P = 0.048), and one-way ANOVA showed no significant diff erence in swimming speed between the two groups (F(1, 1) = 1.528, P = 0.237). (4) In the visual cue test, all rats reached the platform within 15 seconds, with no significant difference (F(1, 1) = 0.579, P = 0.459). (5) During experimentation, all rats increased in body mass, but there was no difference between the two groups (F(1, 1) = 0.05, P = 0.943). At day 28 of 0.05% lead exposure, the blood lead level was 29.72 μ g/L in the lead exposure group and 5.86 μ g/L in the control group (P< 0.01). Conclusion: The present results revealed low-level lead exposure significantly impaired spatial reference memory and spatial working memory, but had no effect on spatial learning.
摘要：
To assess the influence of long-term fertilization on weed communities of early and late rice crops, the weed species composition was investigated in experimental plots initiated in 1981 at the Key Field Experimental Monitoring Station of the Reddish Paddy Soil Eco-Environment in Wangcheng, China. The treatments were (1) a control (CK), no fertilizer; (2) N–P, no K; (3) N–K, no P; (4) P–K, no N; (5) N–P–K; (6) N–P–K + Ca, N, P, and K plus lime; (7) N–P + S, N and P plus additional rice straw return; (8) N–P–K + S, N, P, and K plus additional rice straw; (9) N–K + M, N and K plus swine manure. The results indicated that weed flora composition and density were influenced by the different fertilization treatments. Multivariate analyses indicated that changes in the weed community composition were primarily due to soil-available N, followed by light intensity on the field surface, and soil-available P. More weed species and total weed density were observed in the control and P–K plots than in plots in which N, P, and K were applied together. Omission of N application had a greater effect on the weed community than the omission of P or K applications. Nutrients derived from synthetic fertilizers and organic manure or the additional application of lime had no obvious effect on the weed community of late rice crops. Nomenclature: Rice, Oryza sativa L.
摘要：
The present study was conducted to determine the effects of a polysaccharide of Atractylodes macrophala Koidz (PAM) as a dietary additive on growth performance, immunoglobulin concentration and IL-1β expression in weaned piglets. One hundred and twenty Landrace×Yorkshire piglets weaned at 28 days old (body weight 7·5±0·07 kg) were assigned to five treatment groups (three pens/group, eight piglets/pen) fed maize/soybean-based diets supplemented with 0, 3, 6 or 9 g of PAM/kg diet or antibiotics (0·4 g flavomycin/kg+0·13 g olaquindox/kg). The experimental period was 28 days. With increasing PAM supplementation levels, average daily gain was greater (quadratic, P<0·05) and the ratio of amount fed to live weight (LW) gain (feed/gain) improved (quadratic, P<0·05) during days 14–28 and overall, and diarrhoea incidence decreased (linear, P<0·05) during days 14–28. Supplementation of PAM also increased (quadratic, P<0·05) serum concentrations of interleukin (IL)-2 and IL-6 on day 14, and increased (quadratic, P<0·05) IL-1β expression in jejunal mucosa and lymph nodes. Concentrations of PAM between 6 and 9 g/kg presented the strongest bioactivity compared to the control group or antibiotic-fed group. These findings indicate that PAM is effective in improving growth performance and cytokine response, which suggests that PAM can be used as a diet additive for weanling piglets.
摘要：
The subfamily Siloscinae Gozmány, 1968 and the genus Autochthonus Walsingham, 1891 are recorded from Guangdong Province, China. Autochthonus singulus sp. nov. is described and illustrated. This is the first record of the genus and the subfamily outside the Ethiopian Region.
作者机构：
[Song, H. Q.; Zhao, G. H.; Weng, Y. B.; Mo, X. H.; Li, J.; Lin, R. Q.; Yuan, Z. G.; Zhu, X. Q.] S China Agr Univ, Coll Vet Med, Parasitol Lab, Guangzhou 510642, Guangdong, Peoples R China.;[Zou, F. C.] Yunnan Agr Univ, Coll Anim Sci & Technol, Kunming 650201, Yunnan Province, Peoples R China.;[Liu, W.] Hunan Agr Univ, Coll Vet Med, Changsha 410128, Hunan, Peoples R China.;[Zhu, X. Q.] S China Agr Univ, Coll Vet Med, Parasitol Lab, 483 Wushan St, Guangzhou 510642, Guangdong, Peoples R China.
通讯机构：
[Zhu, X. Q.] S;S China Agr Univ, Coll Vet Med, Parasitol Lab, 483 Wushan St, Guangzhou 510642, Guangdong, Peoples R China.
关键词：
Major Histocompatibility Complex;Schistosoma;Major Histocompatibility Complex Gene;Schistosoma Japonicum;Unweighted Pair Group Method With Arithmetic Average
作者机构：
[He, Feifei; Chen, Qing; Zhang, Fusuo; Su, Fang; Jiang, Rongfeng] Key Laboratory of Plant-soil Interactions of Ministry of Education, Key Laboratory of Plant Nutrition of Minstry of Agriculture, College of Resources and Environmental Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, Haidian District, Beijing 100193, China;[He, Feifei] College of Bioscience and Biotechnology, Hunan Agricultural University, Furong District, Changsha 410128, China
通讯机构：
[Su, F.] K;Key Laboratory of Plant-soil Interactions of Ministry of Education, Key Laboratory of Plant Nutrition of Minstry of Agriculture, College of Resources and Environmental Sciences, China Agricultural University, No. 2 Yuanmingyuan West Road, China
期刊：
Journal of Veterinary Pharmacology and Therapeutics,2009年32:220-221 ISSN：0140-7783
作者机构：
[Chrzistek, K.; Suszko, A.; Szczypka, M.; Lis, M.; Switala, M.; Pozniak, B.; Obminska-Mrukowicz, B.] Wroclaw Univ Environm & Life Sci, Fac Vet Med, Wroclaw, Poland.;[Yi, J.] Hunan Agr Univ, Coll Vet Med, Changsha, Hunan, Peoples R China.
作者机构：
[Distefano, Gaetano; Gentile, Alessandra; La Malfa, Stefano] Univ Catania, Dipartimento OrtoFloroArboricoltura & Tecnol Agro, I-95123 Catania, Italy.;[Vitale, Alessandro] Univ Catania, Dipartimento Sci & Tecnol Fitosanit, I-95123 Catania, Italy.;[Lorito, Matteo] Univ Naples Federico 2, Dipartimento Arboricoltura & Patol Vegetale, I-80055 Portici, NA, Italy.;[Deng, Ziniu] Hunan Agr Univ, Hort & Landscape Coll, Changsha 410128, Hunan, Peoples R China.;[Gentile, Alessandra] Univ Catania, Dipartimento OrtoFloroArboricoltura & Tecnol Agro, Via Valdisavoia 5, I-95123 Catania, Italy.
通讯机构：
[Gentile, Alessandra] U;Univ Catania, Dipartimento OrtoFloroArboricoltura & Tecnol Agro, Via Valdisavoia 5, I-95123 Catania, Italy.
关键词：
Citrus limon;Defence response modification;Disease resistance assays;Real time PCR
摘要：
Constitutive over-expression of antifungal genes from microorganisms involved in plant defence mechanisms represents a promising strategy for conferring genetic resistance against a broad range of plant pathogenic fungi. In the present work, two transgenic lemon clones with the chit42 gene from Trichoderma harzianum were tested for resistance to fungal disease and expression level of defence-related genes was evaluated. Different resistance-related processes, such as production of reactive oxygen species (ROS), systemic acquired resistance (SAR) and induced systemic resistance (ISR), were monitored in transgenic and wild type lemon clones inoculated with Botrytis cinerea, the causal agent of grey mould in citrus. Expression of genes that encode gluthatione peroxidase (GPX), a producer of ROS, chitinases, glucanases (SAR), PAL, HPL, and AOS (ISR) was measured by quantitative PCR during the first 24 h after leaf inoculation. Leaves of transgenic lemon plants inoculated with B. cinerea showed significantly less lesion development than wild type leaves. Tissues from detached leaves of different transgenic lemon clones showed a significant correlation between resistance and transgene expression. On the other hand, the over-expression of the transgenic fungal gene enhanced by two-three folds transcript levels of genes associated with enhanced ROS production and ISR establishment, while the expression of native chitinase and glucanase genes involved in SAR was down-regulated.
摘要：
Laboratory batch experiments were conducted to study arsenic （As） removal from a naturally contaminated soil using phosphoric acid （H_3PO_4） and potassium dihydrogen phosphate （KHEPO_4）. Both H_3PO_4 and KHEPO_4 proved to reduce toxicity of the soil in terms of soil As content, attaining more than 20% As removal at a concentration of 200 mmol/L. At the same time, acidification of soil and dissolution of soil components （Ca, Mg, and Si） resulted from using these two extractants, especially H_3PO_4. The effectiveness of these two extractants could be attributed to the replacement of As by phosphate ions （PO~(3-)_4）. The function of H_3PO_4 as an acid to dissolve soil components had little effects on As removal. KH_2PO_4 almost removed as much As as H_3PO_4, but it did not result in serious damage to soils, indicating that it was a more promising extractant. The results of a kinetic study showed that As removal reached equilibrium after incubation for 360 rain, but dissolution of soil components, especially Mg and Ca, was very rapid. Therefore dissolution of soil components would be inevitable if As was further removed. Elovich model best described the kinetic data of As removal among the four models used in the kinetic study.
