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Biomedical subjects

X Z Li

Publications and source records attributed to X Z Li.

85 records · Page 5Linked to original sources
PubMed1985

Varicocele: temporal considerations.

The pathophysiology of the abnormal spermatogenesis seen in the presence of the varicocele has not been elucidated in spite of extensive study. Furthermore, no satisfactory explanation exists for the bilateral abnormal spermatogenesis seen in a process which is felt to be unilateral in the majority of cases. The present study was designed to determine if a surgically produced unilateral varicocele would lead to ipsilateral testicular changes prior to the onset of contralateral testicular alterations. Utilizing the rat model and microsurgical techniques, the effects of the varicocele on ipsilateral and contralateral spermatogenesis was studied at intervals over 49 days. Mean seminiferous tubular diameter measurements and flow cytometric analysis of testicular tissue were utilized to assess spermatogenesis. A statistically significant decrease in mean seminiferous tubular diameter was seen between day 1 and day 49 in the left testicle. The right testicle tended to demonstrate similar changes but these were not significant by the method of analysis used. Flow cytometric analysis of testis DNA content also revealed a statistically significant difference in the percentage of haploid, diploid and tetraploid cells in the left testis on day 1 as compared to day 49. The right testis again tended to demonstrate similar but not significant changes. Though primarily a unilateral process, bilateral spermatic vein abnormalities were also visualized in some animals. This observation may contribute to the bilateral effect observed. These studies demonstrate that a surgically created left varicocele will result in bilateral testicular alterations. Within the time frame of the study, the ipsilateral alterations progressed to a greater degree.

Animals↗
PubMed1983

Study of nucleolar organizer in women with galactorrhea, or polycystic ovaries, or using oral contraceptive.

In this paper we report on changes of the Ag-stained NOR (Ag-NOR) and Ag-stained acrocentric association (Ag-AA) frequencies in lymphocytes of women with polycystic ovaries, galactorrhea, or taking oral contraceptives. The results showed that Ag-AA frequencies were increased significantly in all three study groups while the Ag-NOR frequencies apparently did not increase. We assume that a difference in average Ag-NOR frequency between the two groups may be a measure of the change in the number of active rRNA genes, and that differences of Ag-AA frequency among populations reflect the change in transcriptional rate of the active rRNA genes.

Adult↗
PubMedDate not supplied

2,4-dichlorophenol degradation by an integrated process: photoelectrocatalytic oxidation and E-Fenton oxidation.

A new reactor system was designed for an integrated process involving photoelectrocatalytic oxidation (PECO) and electro-Fenton (E-Fenton) oxidation. Its efficiency was evaluated in terms of 2,4-dichlorophenol (2,4-DCP) degradation in aqueous solution. In this process, a TiO2 electrode and an iron (Fe) electrode were used as anodes in parallel, while graphite felt (GF) was used as a cathode. When an electrical current is applied between the anodes and the cathode, the iron anode can release Fe2+ and the GF cathode can generate H2O2 continuously in the reaction solution. Under UV-A illumination, while a H2O2-assisted PECO reaction occurs on the surface of the TiO2 photo anode, an E-Fenton reaction takes place in the solution. The experimental results demonstrated that 2,4-DCP degradation in aqueous solution was greatly enhanced because of the interaction between the two types of reactions. Moreover, the effect of pH as an important factor was investigated. It was found that the combined reaction becomes less pH sensitive than the typical E-Fenton reaction and may be suitable for application in a wide pH range.

Catalysis↗