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Biomedical subjects

G H Tang

Publications and source records attributed to G H Tang.

25 records · Page 2Linked to original sources

[Orthodontic wires in a simulated oral environment:change in mechanical properties]

In this study,some different kinds of orthodontic archwires were tested to evaluate the changes of their mechanical properties.The results showed that in oral environment,all wires suffered degradation of their properties:the force-generating capacity decreased and the permanent deformation increased.The force-generating capacity decreased and the permanent deformation increased.The force decay resulted mainly from the tooth movement.The deformation occurred within 7 days.Chinese-NiTi alloy suffered less stress-relaxation and residual deformation than the stainless steel wires.Arch wires with vertical loops showed similar properties with NiTi,which could deliver more constant force.

Journal Article↗

[The inhibitory effect and its mechanism of transferrin on FSH-induced differentiation of granulosa cells].

Transferrins are a class of related metal-binding transport glycoproteins for transporting iron to various organs and tissues of the body. In recent years, it has been reported that the transferrin can play an important role in the local regulation of ovarian function, apart from its iron-binding characteristic. Transferrin could attenuate FSH-induced differentiation of rat and human granulosa cells and its mechanisms were considered as follows: (1) Transferrins partially blocked the binding of FSH with its receptors on granulosa cells and reduced the formation of intracellular cAMP, and therefore inhibited the expression of FSH receptors. (2) Acting sites beyond cAMP formation also existed for the inhibitory effect of transferrin on inhibin and estradiol production. (3) The inhibitory effect of transferrin seemed not to be involved in the changes of protein kinase C activity, the calcium release and "proliferation-differentiation reversed mechanism" in granulosa cells.

Animals↗

Vasectomy and health: cardiovascular and other diseases following vasectomy in Sichuan province, People's Republic of China.

The long-term sequelae of vasectomy were studied in a retrospective cohort study of 4596 vasectomized and 4340 nonvasectomized farmers from eight rural communes in Sichuan, People's Republic of China. The mean duration since the operation was 14.5 years with a range of 10 to 25 years. At the time of evaluation the vasectomized men were generally healthier than the non-vasectomized for a wide range of health indicators including clinical signs of cardiovascular disease, resting ECG changes, positive ECG changes following a maximal stress test, or fundus abnormalities. The lack of association between vasectomy and cardiovascular disease noted in Europe and the USA is supported by the present study conducted in a population with a low prevalence of cardiovascular disease and risk factors.

Adult↗

Sperm autoimmunity in vasectomized men and its relationship to atherosclerotic coronary artery disease.

A study is reported of sperm autoimmunization in 707 men and its relationship with atherosclerotic coronary artery disease. The following groups were studied: healthy vasectomized men (278), healthy non-vasectomized men (231), vasectomized men with atherosclerotic coronary disease (ACD; 87) and non-vasectomized men with ACD(111). The gelatin agglutination test (GAT), tube slide agglutination test (TSAT) and sperm immobilization test (SIT) were used to detect circulating anti-sperm antibodies. Sperm antibodies developed within 6 months of vasectomy and persisted for more than 20 years. There was no difference in the incidence of antibodies in vasectomized healthy and ACD men. The results of this study provide no evidence for an association between cardiac disease and vasectomy.

Adult↗