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141.
The effects of ivermectin on transmission of Onchocerca volvulus 总被引:2,自引:0,他引:2
E W Cupp M J Bernardo A E Kiszewski R C Collins H R Taylor M A Aziz B M Greene 《Science (New York, N.Y.)》1986,231(4739):740-742
Ivermectin, given to onchocerciasis patients as a single oral dose of 200 micrograms per kilogram of body weight, substantially reduced the uptake of Onchocerca volvulus microfilariae by Simulium yahense, an efficient black fly vector of the parasite in the tropical rain forests of West Africa. Three months after treatment, patients given ivermectin infected flies at a significantly lower rate than those who had received diethylcarbamazine or placebo, thereby reducing the number of developing larvae in the vector population. This diminished rate of infectiousness was also evident 6 months after treatment. These results strongly suggest that ivermectin could be effective in interrupting transmission of Onchocerca volvulus for epidemiologically important periods of time. 相似文献
142.
Clinically successful hematopoietic cell transplantation is dependent on hematopoietic stem and progenitor cells. Here we identify the matricellular protein Nephroblastoma Overexpressed (Nov, CCN3) as being essential for their functional integrity. Nov expression is restricted to the primitive (CD34) compartments of umbilical vein cord blood, and its knockdown in these cells by lentivirus-mediated RNA interference abrogates their function in vitro and in vivo. Conversely, forced expression of Nov and addition of recombinant Nov protein both enhance primitive stem and/or progenitor activity. Taken together, our results identify Nov (CCN3) as a regulator of human hematopoietic stem or progenitor cells. 相似文献
143.
Abrar Muhammad Mohsin Xu Hu Aziz Tariq Sun Nan Mustafa Adnan Aslam Muhammad Wajahat Shah Syed Atizaz Ali Mehmood Khalid Zhou Baoku Ma Xingzhu Chen Xianni Xu Minggang 《Journal of Soils and Sediments》2021,21(2):705-723
Journal of Soils and Sediments - Soil organic carbon (SOC) is an important parameter determining soil fertility and sustaining soil health. How C, N, and P contents and their stoichiometric ratios... 相似文献
144.
145.
Gulzar Ahmad Amanullah Jan Muhammad Arif Mohammad Tariq Jan H. Shah 《Journal of plant nutrition》2013,36(14):2069-2082
Field experiments were conducted to evaluate the effects of nitrogen (N) and sulfur (S) levels and their methods of application on canola. Branches plant?1, pods plant?1 and biological yield significantly increased with increase in nitrogen level and no significant increase in seed pod?1 and seed and oil yields occurred beyond 120 kg N ha?1. However, thousand seed weight consistently decreased with increasing level of nitrogen. Pods plant?1 and biological yield continually increased with increase in sulfur level. Alternatively, significant increase in branches plant?1, seed pod?1, seed weight, seed and oil yields was noted with increase in sulfur level up to 40 kg ha?1. Applications of sulfur and nitrogen in split significantly decreased seed yield as compared to sole applications. It is concluded that sulfur and nitrogen application as sole at the rate of 40 and 120 kg ha?1, respectively performed better than the rest of their levels and method of application. 相似文献
146.
The effects of salinity, density, and nutrient on the growth, reproduction, and ecophysiology of a perennial halophyte, Cressa cretica L., were studied. Lower salinity concentration (425 mM) promoted the growth, but the highest salinity (850 mM) did not have a significant effect. Plants grew faster and were healthier at low density treatment. Lack of nitrogen (N) in the medium substantially inhibited shoot growth. Higher rhizome length and increased dry weight were some of the symptoms of N‐deficiency. Phosphorus (P)‐free plants also showed higher dry weight and higher ratio of rhizomes to shoots. Reproductive capacity of Cressa cretica plants was not affected by the absence of P. Growth and reproduction of Cressa cretica plants were significantly inhibited by potassium (K) deficiency. Optimal plant growth was recorded in complete nutrient solution. Higher concentrations of oxalate were found in plants growing under low density conditions and in non‐saline controls. Proline concentration increased with the increase in salinity of the medium. Chlorophyll a and b synthesis were inhibited by high salinity treatments whereas changes in density regimes did not have an effect. 相似文献
147.
Two trials were conducted with two sizes, grow‐out (80.0 mg b.w.) and fattening (5.0 g b.w.), of Penaeus semisulcatus to compare the production and yield of shrimp cultured at different stocking densities within an indoor running‐seawater system. In the first experiment, postlarvae were cultured at 50, 100, 150 and 200 m?3 for 68 days, while in the second experiment, juveniles were cultured at 24, 50, 74 and 100 m?3 for 126 days. The results of the two experiments showed significant decrease in weight of shrimp as the stocking density increased. During the grow‐out stage, no statistical differences were observed on survival rates among the shrimp stocked at different densities. Thus, as the primary factor to consider at this stage is the number of shrimp produced, it is recommended to use a density of 200 shrimp m?3. During the fattening stage, the survival rate at the highest density was statistically lower than the other three densities. The mean yield was 437.02, 869.16, 1217.62 and 1446.78 g m?3 for shrimp stocked at 24, 50, 74 and 100 m?3 respectively. Although the average harvest size of juveniles at the lowest stocking density was statistically higher than those stocked at the highest stocking density, both sizes (18.12 and 16.67 g) will be classified as one size group in the market, i.e. medium. As the yield significantly increases as the stocking density is increased, it is therefore recommended that the stocking density for the fattening stage be 100 shrimp m?3. 相似文献
148.
Yamin Muhammad bin Wan Ismail Wan Ishak Abd Aziz Samsuzana bin Mohd Kassim Muhamad Saufi Akbar Farah Naz Ibrahim Muhammad 《Precision Agriculture》2022,23(4):1413-1448
Precision Agriculture - This research study focuses on the design of variable rate liquid fertilizer applicator which can measure the NPK status of soil and applies N, P and K nutrients... 相似文献
149.
Genotype×tillage interaction and the performance of winter bread wheat genotypes in temperate and cold dryland conditions 下载免费PDF全文
Ebrahim ROOHI Reza MOHAMMADI Abdoul Aziz NIANE Javad VAFABAKHSH Mozaffar ROUSTAEE Mohammad Reza JALAL KAMALI Shahriar SOHRABI Shahriar FATEHI Hossain TARIMORADI 《农业科学学报》2022,21(11):3199-3215
Growing concerns for food security and the alleviation of hunger necessitate knowledge-based crop management technologies for sustainable crop production. In this study, 13 winter bread wheat genotypes (old, relatively old, modern, and breeding lines) were evaluated under three different tillage systems, i.e., conventional tillage (CT, full tillage with residue removed), reduced tillage (RT, chisel tillage with residue retained) and no-tillage (NT, no-tillage with residue retained on the soil surface) in farmer's fields under rainfed conditions using strip-plot arrangements in a randomized complete block design with three replications in the west of Iran (Kamyaran and Hosseinabad locations) over two cropping seasons (2018–2019 and 2019–2020).The main objectives were to investigate the effects of tillage systems and growing conditions on the agronomic characteristics, grain yield and stability performance of rainfed winter bread wheat genotypes.Significant (P<0.01) genotype×tillage system interaction effects on grain yield and agronomic traits suggested that the genotypes responded differently to the different tillage systems. The number of grains per spike and plant height were positively (P<0.0) associated with grain yield under the NT system, so they may be considered as targeted traits for future wheat breeding. Using statistical models, the modern cultivars (“Sadra” and “Baran”) were identified as high yielding and showed yield stability across the different tillage systems. As per each tillage system, genotype “Sadra” followed by “Zargana-6//Dari 1-7 Sabalan” exhibited higher adaption to CT; while cultivars “Jam” and “Azar2” showed better performance under the RT system; and cultivars “Varan” and “Baran” tended to have better performance expression in the NT condition.The increased grain yields achieved in combination with lower costs and greater profits from conservation agriculture suggest that adapted cultivar and NT systems should be evaluated and promoted more widely to farmers in the west of Iran as an attractive package of crop management technologies.In conclusion, variations in the performance of genotypes and the significant genotype×tillage system interaction effects on grain yield and some agronomic traits assessed in this study suggest that the development and selection of cultivars adapted to the NT system should be considered and included in the strategies and objectives of winter wheat breeding programs for the temperate and cold dryland conditions of Iran. 相似文献
150.
Saida Rifai Aziz Fassouane Paulo M. Pinho Anake Kijjoa Nair Nazareth Maria S?o José Nascimento Werner Herz 《Marine drugs》2005,3(1):15-21
Fasciculatin, a furanosesterterpene isolated from the marine sponge Ircinia variabilis from the Atlantic Coast of Morocco, has been evaluated for its influence on a mitogen-induced proliferation of human lymphocytes and growth of human tumor cell lines. 相似文献