[Effects of chemical fertilizer reduction combined with humic acid bio-fertilizer on soil biological properties and dry matter mass of maize.].

A reduction of chemical fertilizers and improving fertilizer utilization rate are important for ensuring a balance between plant growth and minimizing the degradation of the black soil. We conducted a 2-year pot experiment with four treatments during 2019 and 2020, including T: no fertilizer, T: conventional use of chemical fertilizer, T: 15% reduction of the chemical fertilizer combined with 400 kg·hm of humic acid bio-fertilizer (HABF), and T: 30% reduction of the chemical fertilizer combined with 600 kg·hm of HABF, to examine the effect of reduction rates of chemical fertilizers combined with the HABF on soil microbial abundance, enzyme activity and nutrient content in maize cultivation. The results showed that the application of HABF significantly increased the abundance of soil bacteria and fungi, with the number of microbial colonies being positively correlated with the amount of HABF.

Progress in culture and gene editing of porcine spermatogonial stem cells.

Research on culture and gene editing of domestic spermatogonial stem cells (SSCs) is of considerable interest but remains a challenging issue in animal science. In recent years, some progress on the isolation, purification, and genetic manipulation of porcine SSCs has been reported. Here, we summarize the characteristics of porcine SSCs as well current advances in their culture, potential usage, and genetic manipulation.

[Simultaneous determination of five water-soluble vitamins in human serum by high performance liquid chromatography].

Objective: To establish a method for the simultaneous determination of 5 water-soluble vitamins including VB1, VB6, Nicotinic acid, Nicotinamide and Folic acid by high performance liquid chromatography.

Methods: Methanol (200 microL) was added to 50 microL human blood sample to precipitate proteins. The sample was frozen (-18 degrees C) for 30 min, and then centrifuged at 8000 r/min for 8 min.