The possibility of gene flow between two varieties of transgenic rice with bar gene (Y0003 and 99-t) (male) and barnyard grass(Echinochloa crusgalli var. mitis ) (female) was studied by means of reproductive biology. ...The possibility of gene flow between two varieties of transgenic rice with bar gene (Y0003 and 99-t) (male) and barnyard grass(Echinochloa crusgalli var. mitis ) (female) was studied by means of reproductive biology. The germination and growth of rice pollen grains on barnyard grass stigmas at 30 min, and 1-4 h after crossing by hand were observed with an optical microscope. The results were compared with the germination and growth of barnyard grass pollen grains at the corresponding time after self-pollination. The results showed that germination and growth of the pollen grains of the two varieties were similar on barnyard grass stigmas, but differed significantly from self-pollination of barnyard grass. Pollen grains germinated and pollen tubes penetrated stigmas normally, and the number of pollen grains being condensing or releasing their inclusions or having released them increased with the time after self-pollination. Pollen grains of transgenic rice on the stigmas of barnyard grass couldn't germinate or grow normally after crossing, neither could they penetrate the stigmas of barnyard grass. Therefore, it could be concluded that the sexual incompatibility between transgenic rice with bar gene and barnyard grass is due to the rice pollen being unable to penetrate the stigma of barnyard grass. Further proof of incompatibility lies in the fact that the emasculated barnyard grass pollinated with the rice pollen grains could not seed.展开更多
BACKGROUND Streptococcus mitis(S.mitis)is an opportunistic pathogen that can lead to severe ocular infections.In previous reports,penetrating keratoplasty(PK)was usually adopted for the treatment of persistent corneal...BACKGROUND Streptococcus mitis(S.mitis)is an opportunistic pathogen that can lead to severe ocular infections.In previous reports,penetrating keratoplasty(PK)was usually adopted for the treatment of persistent corneal ulcers.This report describes an unusual case of nonhealing descemetocele caused by S.mitis treated by antibiotics plus amniotic membrane transplantation(AMT).CASE SUMMARY A 63-year-old woman presented with a right persistent corneal ulcer that she had suffered from for the past 9 mo.The culture of a corneal scraping yielded S.mitis.The right eye descemetocele decreased in diameter from 3 to 0.8 mm after the continuous administration of topical vancomycin and ceftriaxone for 2 wk.Due to the slow healing,AMT was performed.Her corneal erosion healed and gradually became clear.Her visual acuity recovered from initially counting fingers to 100/200 at the last follow-up,67 mo after AMT.CONCLUSION Antibiotics plus AMT may be an effective alternative treatment other than PK to promote epithelializationand to reduce inflammation in the corneas complicated by S. mitis keratitis.展开更多
Streptococcus mitis is a component of the normal oropharynx, skin, gastrointestinal system, and genital tract florae. It is generally considered as a relatively benign bacterium. We present a case of spontaneous Strep...Streptococcus mitis is a component of the normal oropharynx, skin, gastrointestinal system, and genital tract florae. It is generally considered as a relatively benign bacterium. We present a case of spontaneous Streptococcus mitis meningitis in a patient with liver cirrhosis and no known risk factors for invasive infectious diseases.展开更多
基金the Ministry ofScience and Technology,P.R.ChinaEvaluation of Safety of Transgenic Crops(E200102).
文摘The possibility of gene flow between two varieties of transgenic rice with bar gene (Y0003 and 99-t) (male) and barnyard grass(Echinochloa crusgalli var. mitis ) (female) was studied by means of reproductive biology. The germination and growth of rice pollen grains on barnyard grass stigmas at 30 min, and 1-4 h after crossing by hand were observed with an optical microscope. The results were compared with the germination and growth of barnyard grass pollen grains at the corresponding time after self-pollination. The results showed that germination and growth of the pollen grains of the two varieties were similar on barnyard grass stigmas, but differed significantly from self-pollination of barnyard grass. Pollen grains germinated and pollen tubes penetrated stigmas normally, and the number of pollen grains being condensing or releasing their inclusions or having released them increased with the time after self-pollination. Pollen grains of transgenic rice on the stigmas of barnyard grass couldn't germinate or grow normally after crossing, neither could they penetrate the stigmas of barnyard grass. Therefore, it could be concluded that the sexual incompatibility between transgenic rice with bar gene and barnyard grass is due to the rice pollen being unable to penetrate the stigma of barnyard grass. Further proof of incompatibility lies in the fact that the emasculated barnyard grass pollinated with the rice pollen grains could not seed.
文摘BACKGROUND Streptococcus mitis(S.mitis)is an opportunistic pathogen that can lead to severe ocular infections.In previous reports,penetrating keratoplasty(PK)was usually adopted for the treatment of persistent corneal ulcers.This report describes an unusual case of nonhealing descemetocele caused by S.mitis treated by antibiotics plus amniotic membrane transplantation(AMT).CASE SUMMARY A 63-year-old woman presented with a right persistent corneal ulcer that she had suffered from for the past 9 mo.The culture of a corneal scraping yielded S.mitis.The right eye descemetocele decreased in diameter from 3 to 0.8 mm after the continuous administration of topical vancomycin and ceftriaxone for 2 wk.Due to the slow healing,AMT was performed.Her corneal erosion healed and gradually became clear.Her visual acuity recovered from initially counting fingers to 100/200 at the last follow-up,67 mo after AMT.CONCLUSION Antibiotics plus AMT may be an effective alternative treatment other than PK to promote epithelializationand to reduce inflammation in the corneas complicated by S. mitis keratitis.
文摘Streptococcus mitis is a component of the normal oropharynx, skin, gastrointestinal system, and genital tract florae. It is generally considered as a relatively benign bacterium. We present a case of spontaneous Streptococcus mitis meningitis in a patient with liver cirrhosis and no known risk factors for invasive infectious diseases.
