我国是胃癌的高发病国家之一，这与幽门螺杆菌在我们国家的高感染率（70%左右）密切相关。幽门螺杆菌感染可以导致慢性持续性胃炎，已知慢性持续性胃炎是最终引发胃癌的重要因素之一。虽然幽门螺杆菌感染是导致胃炎的关键因素，但是幽门螺杆菌胃炎的临床表征受遗传、饮食等多种因素影响，神户地震后流行病学调查表明压力可以加重幽门螺杆菌胃炎，但目前对其分子机制并没有相关研究。我们前期研究发现持续性压力可以导致胃内菌群紊乱，而且我们前期已发表研究表明压力诱导肠道菌群紊乱是导致肠激惹综合征（IBS）的重要原因之一，基于此我们提出科学假设：压力诱导胃内菌群紊乱加重幽门螺杆菌胃炎。我们将从菌群平衡角度，通过小鼠恐水模型，应用16srDNA组测序技术以及其它分子生物学技术研究压力诱导胃内菌群紊乱的机制以及紊乱菌群加重幽门螺杆菌胃炎的机制。我们的研究可以为幽门螺杆菌胃炎以至胃癌的预防与控制提供线索。

China is one of the countries with high incidence of gastric cancer, which is closely related to high prevalence (about 70%) of H. pylori infection . H.pylori is a main pathogenic factor resulting in chronic gastritis and peptic ulcer, and is intimately associated with gastric carcinoma. Although H. pylori infection is a key factor leading to gastritis, the clinical manifestations of H. pylori gastritis are influenced by many factors, including genetic background, diet and other subjects. After the Great Hanshin Earthquake, epidemiological survey showed that stress could aggravate the H. pylori gastritis，however the molecular mechanism remains largely unknown. On the basis of former studies, we found that stress could cause stomach flora disturbance, and our previous published studies have shown that stress-induced intestinal flora disorders are one important cause to induce irritable bowel syndrome (IBS).Based on this, we propose scientific hypothesis: H.pylori gastritis is aggravated by dysbacteriosis induced by stress. We'll focus on microbiota homeostasis, using water-avoid stress mouse model, application 16srDNA sequencing and other molecular biology techniques to study the mechanisms of stomach flora disorder induced by stress and H. pylori gastritis aggravated by disorder flora. Our study may provide clues for prevention and control of H. pylori gastritis as well as gastric cancer.