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11.
1—取代苯基—1,4—二氢—6—甲基—4—哒嗪酮—3—酰胺的合成 总被引:3,自引:1,他引:2
用杂交方法培育新作物品种是农业增产的重要措施。与常规杂交育种方法相比,采用化学杀雄法(Chemical induction lf male sterility)育种具有程序简单,节省劳力,时间缩短等优点,可以诱导产生非遗传性的雄性不育母本,与另一品种的文本杂交而得优化组合的良种,国外在小麦上已试验成功但在水稻上尚在探索,美国Rohm and Haas公司曾报道一些哒嗪酮类 相似文献
12.
不同细胞质雄性不育小麦中谷胱甘肽过氧化物酶活性比较 总被引:2,自引:0,他引:2
以几种具有较好应用前景的细胞质雄性不育型小麦为材料 ,对分蘖期小麦叶片中的谷胱甘肽过氧化物酶的活性进行了测定 ,实验结果表明 ,亲本中国春的谷胱甘肽的含量和谷胱甘肽过氧化物酶的比活最高 ,华麦 8号次之 ,细胞质雄性不育小麦均低于保持系中国春与华麦 8号 ,这可能意味着细胞质雄性不育小麦在分蘖期植株体内清除活性氧代谢的能力低于可育品种 ,是小麦以后发育过程花粉走向败育的内在原因之一 . 相似文献
13.
旨在研究比较右手持拍男性乒乓球运动员与普通男性大学生的脊柱形态差异. 利用DIERS光学三维脊柱分析仪各测量了40名男性大学生的脊柱参数. 研究发现右手持拍男性乒乓球运动员的骨盆倾斜距离、脊柱冠状面偏移距离、躯干倾角、脊柱偏移距离、脊柱矢状面偏移距离以及脊柱矢状面偏移角度与普通男性大学生相关指标表现出显著性差异(P<0.05); 右手持拍男性乒乓球运动员胸曲后凸角和腰曲前凸角均值低于普通男性大学生, 但无显著性差异(P>0.05). 结果表明, 乒乓球运动员的脊柱形态产生一定程度的变化可能与其长时间进行单侧的大强度训练有关. 相似文献
14.
徐乃瑜;刘江东 《武汉大学学报(理学版)》1995,(2)
选用属D2型细胞质的粗厚山羊草(Aegilopscrassa)、牡山羊草(Ae.juvenalis)和瓦维洛夫山羊草(Ae.vavilovii)分别与普通小麦(Tr.aestivum)品种鄂恩1号、NPFP和白皮224连续回交进行核置换组配的9个异质系(即核质杂种)[1],和核供体品种鄂恩1号、NPFP和白皮224,于分蘖始期(叶原基期)和拔节始期(小花分化期)分别置于15.5~16h和24h长光照下,以武汉自然光照为对照.抽穗时套袋隔离,取样用碘液进行花粉育性观察.结果表明:(1)三个核供体品种在不同发育时期进行上述光长处理,对雄性不育和结实率没有明显影响.而异质小麦在分率始期给予24h长光照处理,花粉高度不育或全不育,在拔节始期进行上述处理,雄性不育和结实率下降程度大大减低.(2)在异质小麦中以牡山羊草对24h长光照最敏感,其次为粗厚山羊草和瓦维洛夫山羊草.(3)15.5~16h光长对引起雄性不育虽有一定效果,但不及24h光长影响大.(4)在同一异质条件下,不同核对引起雄性不育的程度有异.(5)碘染花粉观察育性与套袋结实率的变化结果相一致.(6)D2型细胞质可作为小麦光周期敏感细胞质雄性不育来源的重要遗? 相似文献
15.
以花粉可育率和自然结实率为指标,对红莲型细胞质雄性不育系丛广41 A 与其恢复系配制的 F1 、 F2 、 B C1 和 B C2 等世代的育性表现进行了调查,结果表明,红莲型细胞质雄性不育系丛广41 A 属配子体不育,其不育性受一对隐性核主基因和不育细胞质共同控制,其核不育基因与珍汕 97 A 不等位 其恢复性受显性单基因控制,密阳 23 有一对强恢复基因,珍汕 97 有一对弱恢复基因 相似文献
16.
G protein-coupled receptors (GPCRs) are involved in several physiological processes, and they represent the largest family of drug targets to date. However, the presence and function of these receptors are poorly described in human spermatozoa. Here, we aimed to identify and characterize the GPCRs present in human spermatozoa and perform an in silico analysis to understand their potential role in sperm functions. The human sperm proteome, including proteomic studies in which the criteria used for protein identification was set as <5% FDR and a minimum of 2 peptides match per protein, was crossed with the list of GPCRs retrieved from GLASS and GPCRdb databases. A total of 71 GPCRs were identified in human spermatozoa, of which 7 had selective expression in male tissues (epididymis, seminal vesicles, and testis), and 9 were associated with male infertility defects in mice. Additionally, ADRA2A, AGTR1, AGTR2, FZD3, and GLP1R were already associated with sperm-specific functions such as sperm capacitation, acrosome reaction, and motility, representing potential targets to modulate and improve sperm function. Finally, the protein-protein interaction network for the human sperm GPCRs revealed that 24 GPCRs interact with 49 proteins involved in crucial processes for sperm formation, maturation, and fertilization. This approach allowed the identification of 8 relevant GPCRs (ADGRE5, ADGRL2, GLP1R, AGTR2, CELSR2, FZD3, CELSR3, and GABBR1) present in human spermatozoa that can be the subject of further investigation to be used even as potential modulatory targets to treat male infertility or to develop new non-hormonal male contraceptives. 相似文献
17.
Prof. Dr. Jinfei Yang Dengfeng Lin Weiwei Yao Damin Yun Liwei Zhou Sheng Gao Prof. Dr. Fei Sun 《ChemistryOpen》2022,11(3):e202100219
18.
《Biomedical chromatography : BMC》2017,31(8)
Male factor infertility is involved in almost half of all infertile couples. Lack of the ejaculated sperm owing to testicular malfunction has been reported in 6–10% of infertile men, a condition named nonobstructive azoospermia (NOA). In this study, we investigated untargeted metabolomic profiling of the seminal plasma in NOA men using gas chromatography–mass spectrometry and advance chemometrics. In this regard, the seminal plasma fluids of 11 NOA men with TESE‐negative, nine NOA men with TESE‐positive and 10 fertile healthy men (as a control group) were collected. Quadratic discriminate analysis (QDA) technique was implemented on total ion chromatograms (TICs) for identification of discriminatory retention times. We developed multivariate classification models using the QDA technique. Our results revealed that the developed QDA models could predict the classes of samples using their TIC data. The receiver operating characteristic curves for these models were >0.88. After recognition of discriminatory retention time's asymmetric penalized least square, evolving factor analysis, correlation optimized warping and alternating least squares strategies were applied for preprocessing and deconvolution of the overlapped chromatographic peaks. We could identify 36 discriminatory metabolites. These metabolites may be considered discriminatory biomarkers for different groups in NOA. 相似文献
19.
微量元素与男性不育症 总被引:1,自引:0,他引:1
对近年微量元素与男性不育症关系的研究进行了综述,并介绍了一些宏量元素对男性生育功能的影响。 相似文献
20.
Jung-Sun Kim Ji-Min Han Yoon-Sook Cho Kyung-Hee Choi Hye-Sun Gwak 《Molecules (Basel, Switzerland)》2021,26(11)
Background: Although nilotinib hepatotoxicity can cause severe clinical conditions and may alter treatment plans, risk factors affecting nilotinib-induced hepatotoxicity have not been investigated. This study aimed to elucidate the factors affecting nilotinib-induced hepatotoxicity. Methods: This retrospective cohort study was performed on patients using nilotinib from July of 2015 to June of 2020. We estimated the odds ratio and adjusted odds ratio from univariate and multivariate analyses, respectively. Several machine learning models were developed to predict risk factors of hepatotoxicity occurrence. The area under the curve (AUC) was analyzed to assess clinical performance. Results: Among 353 patients, the rate of patients with grade I or higher hepatotoxicity after nilotinib administration was 40.8%. Male patients and patients who received nilotinib at a dose of ≥300 mg had a 2.3-fold and a 3.5-fold increased risk for hepatotoxicity compared to female patients and compared with those who received <300 mg, respectively. H2 blocker use decreased hepatotoxicity by 11.6-fold. The area under the curve (AUC) values of machine learning methods ranged between 0.61–0.65 in this study. Conclusion: This study suggests that the use of H2 blockers was a reduced risk of nilotinib-induced hepatotoxicity, whereas male gender and a high dose were associated with increased hepatotoxicity. 相似文献