Objective To investigate the prevalence rate of thyroid nodules as well as related influencing factors. Methods In this clinical study, 8,912 healthy people were included, involving medical staff, teachers, electric enterprise staff and civil authorities from January to December in 2014 . The prevalence rate of thyroid nodules and related influencing factors were investigated . Results (1) The prevalence rate of thyroid nodules was 40.4%, 34.9%for male and 46.7%for female. The prevalence of female was higher than that of male (P<0.001);(2) The prevalence rate of thyroid nodules showed a trend of increase with age (P<0.01);(3) The prevalence rate of thyroid nodules in medical staff and teachers was significantly higher than others (P<0.001);(4) The difference was statistically significant in BMI, blood pressure, blood lipid, blood glucose in thyroid nodule group and non thyroid nodules group (P<0.001). All indexes mentioned above of thyroid nodule group was much higher than those of non thyroid nodules group. (5) The prevalence rate of breast hyperplasia of females under the age of fifty years was significantly higher than those of non thyroid nodule group (P<0.001). Conclusion The prevalence rate of thyroid nodules is high. It is related to gender, age, occupation and estrogen. Effective measures should be taken to change people's bad habits, blood sugar control and blood pressure, reduce BMI and work tension in order to reduce the incidence of thyroid nodules.

Gene therapy represents a promising treatment for the Alzheimer׳s disease (AD). However, gene delivery specific to brain lesions through systemic administration remains big challenge. In our previous work, we have developed an siRNA nanocomplex able to be specifically delivered to the amyloid plaques through surface modification with both CGN peptide for the blood-brain barrier (BBB) penetration and QSH peptide for -amyloid binding. But, whether the as-designed nanocomplex could indeed improve the gene accumulation in the impaired neuron cells and ameliorate AD-associated symptoms remains further study. Herein, we prepared the nanocomplexes with an siRNA against -site amyloid precursor protein-cleaving enzyme 1 (BACE1), the rate-limiting enzyme of A production, as the therapeutic siRNA of AD. The nanocomplexes exhibited high distribution in the A deposits-enriched hippocampus, especially in the neurons near the amyloid plaques after intravenous administration. In APP/PS1 transgenic mice, the nanocomplexes down-regulated BACE1 in both mRNA and protein levels, as well as A and amyloid plaques to the level of wild-type mice. Moreover, the nanocomplexes significantly increased the level of synaptophysin and rescued memory loss of the AD transgenic mice without hematological or histological toxicity. Taken together, this work presented direct evidences that the design of precise gene delivery to the AD lesions markedly improves the therapeutic outcome.