Water stress memory in wheat/maize intercropping regulated photosynthetic and antioxidative responses under rainfed conditions.

Drought is a most prevalent environmental stress affecting the productivity of rainfed wheat and maize in the semiarid Loess Plateau of China. Sustainable agricultural practices such as intercropping are important for enhancing crop performance in terms of better physiological and biochemical characteristics under drought conditions. Enzymatic and non-enzymatic antioxidant enzyme activities are associated with improved abiotic tolerance in crop plants, however, its molecular mechanism remains obscure. A 2-year field study was conducted to evaluate the influence of intercropping treatment viz. wheat mono-crop (WMC), maize mono-crop (MMC), intercropping maize (IM) and wheat (IW) crops, and nitrogen (N) application rates viz. control and full-dose of N (basal application at 150 and 235 kg ha-1 for wheat and maize, respectively) on chlorophyll fluorescence, gas exchange traits, lipid peroxidation, antioxidative properties and expression patterns of six tolerance genes in both crops under rainfed conditions. As compared with their respective monocropping treatments, IW and IM increased the Fo/Fm by 18.35 and 14.33%, PS-11 efficiency by 7.90 and 13.44%, photosynthesis by 14.31 and 23.97%, C-capacity by 32.05 and 12.92%, and stomatal conductance by 41.40 and 89.95% under without- and with-N application, respectively. The reductions in instantaneous- and intrinsic-water use efficiency and MDA content in the range of 8.76-26.30% were recorded for IW and IM treatments compared with WMC and MMC, respectively. Compared with the WMC and MMC, IW and IM also triggered better antioxidant activities under both N rates. Moreover, we also noted that intercropping and N addition regulated the transcript levels of six genes encoding non-enzymatic antioxidants cycle enzymes. The better performance of intercropping treatments i.e., IW and IM were also associated with improved osmolytes accumulation under rainfed conditions. As compared with control, N addition significantly improved the chlorophyll fluorescence, gas exchange traits, lipid peroxidation, and antioxidant enzyme activities under all intercropping treatments. Our results increase our understanding of the physiological, biochemical, and molecular mechanisms of intercropping-induced water stress tolerance in wheat and maize crops.

Selection of surgical methods for breast cancer and follow-up analysis / 国际外科学杂志

Objective:To analyze the surgical methods of operable breast cancer and analyze the follow-up results.Methods:A retrospective analysis of the clinical and pathological data of 636 operable breast cancer patients admitted to Zibo First Hospital from July 2008 to April 2018, including the clinical stage, pathological staging. Analyze of the proportion of four surgical methods, and through follow-up, analyze the treatment effect of different surgical methods.Results:All patients are female, aged 26-80 years, the clinical stage of 636 patients: Tis 18 cases, stage Ⅰ 143 cases, stage Ⅱ 354 cases, stage Ⅲ 114 cases, stage Ⅳ 7 cases. There are four types of surgery: ① breast conserving surgery + sentinel lymph node biopsy in 124 cases (19.50%); ② breast conserving surgery + axillary lymph node dissection in 39 cases (6.13%); ③ mastectomy + sentinel lymph node biopsy in 163 cases (25.63%); ④ modified radical surgery in 310 cases (48.74%). Sentinel lymph node biopsy in 427 cases (67.14%), success in 404 patients (94.61%); all patients with lymph node negative 384 cases (60.38%). Follow-up for 1 to 9 years, 11 cases of local recurrence after breast-conserving surgery, It accounted for 6.75% of breast-conserving surgery; 43 cases of local recurrence of chest wall after mastectomy, accounting for mastectomy 9.09%; 33 cases of recurrence and metastasis of axillary lymph nodes and supraclavicular lymph nodes, 4 cases of axillary recurrence after sentinel lymph node biopsy.Conclusions:The proportion of breast-conserving surgery in this group of patients was high and the local recurrence rate of breast-conserving surgery was less than that of mastectomy group; the proportion of simple modified radical surgery declined further; patients with axillary lymph node metastasis were less in the whole group. The choice of reasonable operation method is an important factor to improve the prognosis of breast cancer.