As with any screening test, and most vaccines, the process is not 100 percent effective, and a small number of women with precancerous cells escape detection with false negative tests, for example.

如同大多数疫苗一样，任何筛选试验的程序都不是百分之一百的有效。举例来说，有一小部分妇女的癌前期病变细胞在筛选试验中显示假阴性而逃过了检测。

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False negative tests can result from low worm counts, immature infections and all male infections.

心蠕虫数量小、未成熟或仅有雄虫感染时会导致检测出现假阴性。

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The study's authors suggest women who have had negative results over years of negative tests are at little chance of developing the disease after the menopause.

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The decision by New York Presbyterian Hospital not to discipline Dr. Moses and to allow him to continue to operate was made in light of the negative tests and a court-ordered examination of Dr. Moses in May 2006 by a forensic psychiatrist who opined that he had no cocaine addiction problem.

FORBES: New York Post Disavows Portions Of Article About Jeffrey Moses

Results were not made public by authorities but Sergi said the tests were negative.

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