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631.
Immune responses of whiteleg shrimp,Litopenaeus vannamei (Boone, 1931), to bacterially expressed dsRNA specific to VP28 gene of white spot syndrome virus 下载免费PDF全文
G Taju N Madan S Abdul Majeed T Raj Kumar S Thamizhvanan S K Otta A S Sahul Hameed 《Journal of fish diseases》2015,38(5):451-465
In this study, dsRNA specific to VP28 gene of white spot syndrome virus (WSSV) of shrimp was synthesized in Escherichia coli in large scale and studied the immune response of shrimp to dsRNA‐VP28. The haematological parameters such as clotting time and total haemocytes counts, and immunological parameters such as prophenoloxidase (proPO), superoxide dismutase (SOD), superoxide anion (SOA) and malondialdehyde content, as well as the mRNA expression of ten immune‐related genes were examined to estimate the effect of dsRNA‐VP28 on the innate immunity of Litopenaeus vannamei. The activities of proPO, SOA and SOD significantly increased in haemocyte after dsRNA‐VP28 treatment, whereas MDA content did not change significantly. Among the ten immune‐related genes examined, only the mRNA expression of proPO, cMnSOD, haemocyanin, crustin, BGBP, lipopolysaccharides (LPs), lectin and lysozyme in haemocytes, gill and hepatopancreas of L. vannamei, was significantly upregulated at 12 h after dsRNA‐VP28 treatment, while no significant expression changes were observed in Toll receptor and tumour receptor genes. The increase of proPO and SOD activities, and SOA level and mRNA expression level of proPO, cMnSOD, haemocyanin, crustin, BGBP, LPs, lectin and lysozyme after dsRNA‐VP28 stimulation indicate that these immune‐related genes were involved in dsRNA‐VP28‐induced innate immunity in shrimp. 相似文献
632.
Juan Carlos Molinero Li‐Chun Tseng Lucia Lopez‐Lopez Ulrich Sommer Sami Souissi Jiang‐Shiou Hwang 《Fisheries Oceanography》2016,25(6):555-564
Global environmental changes threaten the sustainable use of resources and raise uncertainties regarding marine populations' responses in a changing Ocean. The pelagic copepods of the genus Calanus play a central role in shelf ecosystems transferring phytoplankton carbon to harvested populations, from boreal to temperate regions. Here we examined a 15‐yr time series of Calanus sinicus abundance in regards to climate forcing in the East China Sea. We identified a compound effect of the Pacific Decadal Oscillation (PDO) and the East Asian Winter Monsoon (EAWM) on environmental conditions in the East China Sea. Such climate influences not only a southward transport of C. sinicus from its population centres into the Taiwan area, but favours advantageous thermal conditions for the species as well. On the interannual scale, our results show that the population size of C. sinicus echoes climate‐driven temperature changes. Hence, the possibility of using the PDO and EAWM variability for assessing and predicting interannual abundance changes of C. sinicus in the East China Sea is considered. The observed close relationship between climate and C. sinicus may promote bottom‐up controls in the pelagic food web, further influencing the southern edge of the species' geographic distribution. Owing to the prominent role this species plays in food web dynamics these results might help integrative fisheries management policies in the heavily exploited East China Sea. 相似文献
633.
The Nutrient Expert decision support system improves nutrient use efficiency and environmental performance of radish in North China 下载免费PDF全文
ZHANG Jia-jia DING Wen-cheng CUI Rong-zong LI Ming-yue Sami ULLAH HE Ping 《农业科学学报》2022,21(5):1501-1512
Excessive fertilization has led to nutrient use inefficiency and serious environmental consequences for radish cultivation in North China.The Nutrient Expert(NE) system is a science-based,site-specific fertilization decision support system,but the updated NE system for radish has rarely been evaluated.This study aims to validate the feasibility of NE for radish fertilization management from agronomic,economic,and environmental perspectives.A total of 46 field experiments were conducted over four... 相似文献
634.
Céleste Pritchard Sami Al-Nadaf Robert B. Rebhun Jennifer L. Willcox Katherine A. Skorupski Amandine Lejeune 《Veterinary and comparative oncology》2023,21(4):717-725
Palliative chemotherapy options for dogs with macroscopic non-osseous mesenchymal tumours are limited. The purpose of this study was to assess the response rate of these tumours to carboplatin chemotherapy. Medical records of 28 dogs treated with carboplatin for macroscopic mesenchymal neoplasia between 1990 and 2022 were retrospectively reviewed. Sixteen dogs with soft tissue sarcoma and 12 dogs with haemangiosarcoma were included. Responses observed included one complete response and three partial responses, for an overall response rate of 14.2% (4/28) and median time to progression of 42 days (range 21–259 days). Responses were only seen in patients with haemangiosarcoma, for a response rate of 33.3% (4/12) and median time to progression for responders of 103 days (range 39–252 days). Median time to progression for dogs with metastatic disease was similar to those with only local disease (distant median: 44 days; local median: 23 days, p = 0.56). Dogs with chemotherapy-naïve disease were compared to dogs having received previous chemotherapy treatment and had a median time to progression of 75 days and 40.5 days respectively (p = 0.13). Twenty-two dogs experienced 48 adverse events, with most being grade 1 or 2 (79%). Carboplatin was well tolerated, with variable macroscopic anti-tumour activity and short response duration. Carboplatin may be an acceptable rescue option for dogs with macroscopic haemangiosarcoma, especially those patients that cannot receive doxorubicin. 相似文献