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Abstract – Aims: The aim of this study was to retrospectively evaluate iatrogenic dental root damage, caused by two different techniques that utilized bone anchor screws, for intermaxillary fixation (IMF) in orofacial trauma. Materials and methods: The techniques used included either predrilled or drill‐free bone anchor screws. A total of 123 patients who required IMF were evaluated (97 men and 26 women). Sixty‐four patients were treated in the predrilled group, and 59 patients were treated in the drill‐free group. The data were collected over an 8‐year period and were analyzed using crosstabs and Fisher’s exact test. Results: Injuries to dental roots were found only in the predrilled group. Twenty‐nine patients (45.3%) were injured at the time of surgery. One year after surgery, 10 patients (15.6%) had permanently injured dental roots. There was a significant difference in injury rates between the predrilled and drill‐free groups 1 year after surgery (P < 0.001). Conclusion: There is an increased potential risk of iatrogenic injury and permanent damage to the dental roots when a technique that involves predrilled holes for bone anchor screws is used.  相似文献   
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Background

The ethnic usage of exotics and indigenous problem plants is a highly debated topic, as legislative requirements over-shadow their potential medicinal value, particularly to treat sexually transmitted infections (STIs). Limited information exists regarding their medicinal value among the Bapedi.

Objectives

To ascertain the importance of exotics and indigenous problem plants in the treatment of STIs, a major global primary health care challenge.

Methods

A field observation and semi-structured questionnaire focussing on species diversity, types of STIs treated and medicinal preparation as well as application was used to collect data from 34 traditional healers.

Results

Seven exotics and three indigenous problem species were identified. These species were used to treat four STIs; with Catharanthus roseus illustrating its dominance in the treatment of gonorrhoea. Some medicinal species used by Bapedi traditional healers have been validated through scientific research or through their extensive use by various cultures in South Africa and other parts of Africa. To the best of our knowledge Alternanthera pungens, Caesalpinia decapetala, Cinnamomum verum, and Citrullus lanatus are reported for the first time in the treatment of the investigated STIs.

Conclusions

Exotic and indigenous problem species constitute an important component of the STIs treatment protocol. Their utilization by Bapedi cautions against the narrow-minded approach of indiscriminate eradication, as these species can play a significant role in the primary health care needs of socio-economic vulnerable people.  相似文献   
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To investigate the role of sex steroids of the seminal fluid on sperm quality, the relationships between sex steroids and milt quality parameters (sperm motility and sperm production) were investigated in the Persian sturgeon. The seminal fluid levels of 17α,20β,21-trihydroxy-4-pregnen-3-one (20βs), and 11-ketotestosterone (11-KT) had positive relationships with sperm motility characteristics (percentage and duration of motility) and sperm density. Also, no relationships were found between other sex steroids including: Testosterone (T), progesterone (P), 17α-hydroxyprogesterone (OHP), and milt quality parameters. The good correlation of 20βs and 11-KT of the seminal fluid with sperm motility and sperm density suggests that these steroids may be important hormones involving in final maturation of the Persian sturgeon spermatozoa.  相似文献   
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Purpose

The real mechanisms of intensive exercise training-induced energy efficiency have not yet been well examined. Therefore, the aim of the present study was to investigate the effects of sprint interval training (SIT) on gene expression of uncoupling proteins (UCPs) and endothelial nitric oxide synthase (eNOS).

Methods

For this purpose, 16 Albino Wistar rats (250–300 g) were randomly divided into equal groups of control and sprint training. The animals run on treadmill for 10 weeks, 5 days per week at intensity corresponding to 90–95% maximal oxygen consumption. The gene expression of UCP2, UCP3 and eNOS was analyzed by RT-PCR method in hearts. The data were analyzed by independent samples T test at P?<?0.05 level.

Results

Sprint interval training significantly decreased mRNA expression of UCP2 (t14?=?4.818, P?=?0.001) and UCP3 (t14?=?4.620, P?=?0.001) in cardiac muscle of rats. In contrast, mRNA expression of eNOS in cardiac muscle significantly increased following sprint interval training (t14?=?7.967, P?=?0.001).

Conclusion

This study elucidates that SIT through reduction in gene expression of uncoupling proteins can improve energy efficiency. But, more studies are needed to confirm this hypothesis.

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