搜索结果: 1-7 共查到“性医学 Nature:”相关记录7条 . 查询时间(0.14 秒)
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哈佛医学院的Steven McCarroll及其同事利用这种方法分析了20名供体的31,000多个精子细胞,并将结果发表在《Nature》杂志上。他们发现,人与人之间、细胞之间甚至染色体之间,交叉重组(crossover)及其他减数分裂的表型都是不同的。
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海绵体组织是男性外生殖器的重要组成部分,具有完整海绵窦结构的健康海绵组织是维持阴茎正常勃起功能和泌尿功能的前提。
多种疾病或外伤可能会导致阴茎发育畸形或缺损,严重影响患者性功能和生殖功能,最终需要重建海绵体组织。然而由于各种解剖学,美学和功能方面的挑战,海绵体缺损的修复一直很难取得满意的效果。
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大多数哺乳动物雄性中的性染色体只有一个很小的同源片段,这段区域被称为假常染色体区(Pseudoautosomal region, PAR),PAR区域正确发生DNA双链断裂、配对以及交换才能确保减数分裂的正常进行。在小鼠减数分裂重组过程中,发生DNA双链断裂的PAR区域大小只有大约700kb。在常染色体中平均每10Mbp发生一次DNA双链断裂,PAR区域如果与典型的常染色体区段表现相同的话,肯定会...
Nature of alpha subunit secretion in men:circadian rhythms, pulsatile release and secretory profiles
alpha subunit secretion men circadian rhythms pulsatile release secretory profiles
2009/2/23
Alpha subunit complements LH as a marker of the activity of the hypothalamic GnRH pulse generator. To characterize episodes of alpha subunit release and to determine if a circadian pattern of alpha ...
Nature of the Clearance of Exogenous Testosterone and Progesterone in Ejaculated Bovine Semen
progesterone testosterone blood semen ejaculated
2009/2/19
Plasma and semen concentrations of androgens and progestins were not influenced by repetitive ejaculation in bulls. Within 20 minutes after the injection of testosterone (100 mg Intravenously), plas...
Cavernosus Muscle Contraction During Erection:Is It Voluntary or Reflex, Given the Striated Nature of the Muscles?
Ischio-/bulbo-cavernosus muscle corpora cavernosa intracorporal pressure electromyography
2008/12/24
The bulbo- and ischio-cavernosus muscles (BCM, ICM) contract in the rigid erection phase, leading to a suprasystolic cavernosal pressure. We investigated the hypothesis that the contraction of caver...
Nurture vs Nature: How Can We Optimize Sperm Quality?
Nurture Nature: Optimize Sperm Quality
2008/12/19
The number and quality of sperm produced by the testis is determined to a great extent by the interaction of three factors: 1) the genetic make-up of the spermatogonia; 2) normal Sertoli and Leydi...