Vein fluorite and barite deposits in southeast Sichuan occur mainly in the Lower Ordovician carbonate rocks.

川东南脉状萤石-重晶石矿床主要产于下奥陶统碳酸盐岩中。

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The investigation shows that the potential regions and target areas occur mainly in the North China and South China gas accumulation regions.

研究表明：中国煤层气的有利聚气带和目标区主要分布在华北聚气区和华南聚气区；

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Conclusion the prevalence of cholera in Hainan in 2005 occur mainly during the dining together parties through food-borne transmission and the principal risk factor is eating seafood.

结论聚餐爆发是海南省2005年霍乱的主要流行形式，经食物传播是唯一的传播途径，海产品是主要的危险因素。

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That's plenty of time to protect against influenza, which tends to occur mainly in January and February.

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Meanwhile, Cubist's injectible entrant, Cidecin, is incredibly powerful against some bacteria but will be useful mainly for infections that occur in hospitals.

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