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91.

Research question

Previous studies of aromatase inhibitors on male infertility have focused on men with low testosterone–oestradiol ratio of less than 10. Can aromatase inhibitors improve spermatogenesis in men with idiopathic male infertility with normal testosterone–oestradiol ratio?

Design

Prospective study of men with idiopathic severe oligozoospermia (sperm concentration <5 million/ml) carried out between February 2015 and March 2017. The objective was to assess if semen-analysis parameters improved after treatment with letrozole. Secondary objectives were to monitor the safety of letrozole in men, and to measure the alterations in serum FSH, LH, oestradiol and testosterone levels.

Results

Fifteen men with normal testosterone–oestradiol ratio (>10) were treated with letrozole 2.5 mg daily for 4 months. This produced a 5.5-fold increase in sperm concentration (P?=?0.0068). All men had increased total serum testosterone and suppressed oestradiol levels after treatment, thus raising the overall testosterone–oestradiol ratio (P < 0.0001). Adverse effects from letrozole were relatively minor and included loss of libido (54%), headaches (25%), fatigue (21%), weakness (13%), loss of hair (8%) and dry mouth (8%).

Conclusions

Letrozole improves sperm concentration and increases testosterone–oestradiol ratio for men with oligozoospermia who have normal testosterone–oestradiol ratio; its role in the treatment of male infertility may be extended to this group of patients. In addition, it is a relatively well-tolerated drug with no serious adverse effects.  相似文献   
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There are various modifications of the transverse rectus abdominis musculocutaneous flap and deep inferior epigastric perforator flap to reduce the morbidity of the donor site or to augment the vascularity of the flap. For microanastomosis of multiple pedicles, multiple recipient vessels or an intervening vein graft should be provided. In addition, alternative perforator‐based flaps used in breast reconstruction have small caliber pedicles. Therefore, small recipient vessels such as internal thoracic artery perforators are more suitable for appropriate microanastomosis. Therefore, it is important to acquaint the distribution and anatomical characteristics of internal thoracic artery perforators. We researched the perforators running in the intercostal spaces under the pectoralis major muscle to provide an overview of the anatomical distribution and characteristics of the perforators in patients who underwent immediate subpectoral implant‐based breast reconstructions. In our study, the major perforators (diameter > 1.5 mm) were easily found 2–7 cm medially between the third and fourth intercostal space and were sparse in the lateral area from the midline of the breast (usually 8–9 cm lateral to the midsternal line) and above the third rib. In each side of the breast, the average number of perforators greater than 1.5 mm was 1.6, and the average number of perforators between 1 mm and 1.5 mm in diameter was 3.2. Our results provide information about perforators in the anterior chest wall related to the breast area. Clin. Anat. 32:471–475, 2019. © 2018 Wiley Periodicals, Inc.  相似文献   
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