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11.
运用DNA荧光探针结合显微荧光术,系统地研究了3种水稻细胞质雄性不育系的败育过程、时期和特点.结果表明,珍汕97不育系不能完成小孢子第一次有丝分裂;马协不育系小孢子可完成第一次有丝分裂,但不能进入第二次有丝分裂;广丛41不育系部分小孢子可完成第二次有丝分裂,因此可看到许多三核花粉,但因核行为异常而败育.小孢子的败育过程可能是一种程序性细胞死亡(PCD)的过程  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斯植株体内清除活性氧代谢的能力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   
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14.
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   
15.
董娟娥  马希汉 《色谱》2007,25(2):217-220
建立了利用反相高效液相色谱法(RP-HPLC)同时测定杜仲雄花及其产品中京尼平苷酸和绿原酸的方法。所用的色谱柱为Shim-pack VP-ODS(150 mm×4.6 mm,5 μm),流动相组成为甲醇-水-乙酸(体积比为24∶75∶1),检测波长为240 nm。在该色谱条件下,京尼平苷酸的含量在0.025~0.400 g/L、绿原酸的含量在0.075~1.200 g/L范围内线性关系良好,相关系数分别为0.9997和0.9999;加标回收率分别为100.2%和100.5%。该法适用于杜仲雄花及其产品中这2种成分的含量分析。  相似文献   
16.
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   
17.
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   
18.
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   
19.
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   
20.
A radiometric system originally developed for testing of blood samples obtained from patients suffering from bacteraemia has been adapted for sterility testing of radiopharmaceuticals. Radiometric sterility tests on 202 batches of 19 different radio-pharmaceutical injections were performed and compared with the conventional sterility test method. This technique is more sensitive and rapid than the conventional method.

The radiometric method can be used for injectable radiopharmaceuticals of the radionuclides 35S, 51Cr, 57Co, 58Co, 59Fe, 82Br, 86Rb, 99mTc, 113mIn, 123I and 169Yb. The method is not applicable to iodine-131 labelled radiopharmaceuticals owing to the interference of volatile and radioactive xenon-131m. In the case of neohydrin-203Hg it is necessary to carry out the test after removal of the radioactive material by filtration through a microbe retaining filter.  相似文献   
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