In order to evaluate the reproductive toxicity of environmental horm ones and explore them echanism of male infertility,the present experiment used in situ ending labeling (ISEL) assay to analyse the effects of environmental chemicals on apoptosis Firstly established the method of ISEL ,and secondly used the ISEL to measure the reproduction tox icity of GnRH-A.ISEL has the advantages of high specifity and sensitivity, and good repetition. In situ analysis of developing test is demonstrated that sperm atocytes and sperm atogon ia constituted the major PCD cell types That PCD rate in GnRHA group was apparently higher than that of the control group showed that GnRH -A is an apogen exerting reproduction toxicity.

Human cytomegalovirus (HCMV) and Toxoplasma gondii (Tox) were detected intissues of abortions and stillbirths Diagnosticmethods involved virus isolation, nested PCR,restriction endonucleases analyses of HCMV and the etiological isolation of Tox- trophozoites through m ice inoculation and single PCR to Tox The results showed, that among28 stillbirths and abortions HCMV DNA was found in the lung tissue of one fetal death ,which was negative in virus isolation. Tox DNA was positive in all tissues of a stillbirth including the heart, lungs, brain, liver, kidney ,and eye tissues Tox tachyziotes was isolated from the brain ,lung ,eye and liver tissues in the fetal death through animal inocuation but negative resultswere seen in the heart and kidney .A ll these suggests that some abortions and stillbirths result from fetal infection w ith HCMV or Tox, PCR, being more sensitive and rapid than pathogen isolation, m ight be useful for early diagnosis of abortions and stillbirths w ith HCMV or Tox infection.

The micromass culture was used to determine the effects of vanadium pentoxide(v2O5)on the proliferation and differentiation of limb bud cells of rat．In the in vitro test,the results showed that V2O had obvious inhibiting effects on both proliferation and difierentiation of limb bud cells with a dose-dependent response，its proliferating and differentiating IC50 being 13．64 and 4．77 Vmol／L，respectively． In the in vivo/in vitro test，the results showed that V2O5 had no obvious effect on cell proliferation but had obvious inhibiting effect on cell differentiation．These results indicated that V205 might have a specific inhihifing effec t on the differentiation oflim b bud cells．