全自动吸乳挤奶器的研制

本文介绍一种集吸乳和挤乳为一体的新型全自动多功能吸乳挤奶器,它克服以往人工吸奶器使用不方便,效果不理想等缺点,能安全,自动,舒适地对产妇进行负压吸乳和正压挤乳,以促进乳汁的分泌和排出,提高纯母乳喂养率。     

静磁场对单株人体体表正常菌生长影响的研究

本文通过40mT和120mT两种静磁场作用下表皮葡萄球菌生长过程的研究,发现试验所选强度静磁场加速了表皮葡萄球菌在对数生长期的生长速率,而在进入稳定生长期后其生长速率反而低于对照组,但就整个生长周期而言,静磁场作用下表皮葡萄球菌的总量大于对照组,表明了试验所选静磁场对表皮葡萄球菌生长有一定促进作用.     

清栓酶作用机理研究

本文应用动物DIC模型进行清栓酶作用机理的实验研究,观察指标包括应用清栓酶前后血浆中6-K-PGF_2α,TXB_2,全血粘度等的变化以及脑、肺、肾等脏器的不同病理改变。实验结果表明,A组血中TXB_2增高明显,全血粘度增高,病理改变以血栓形成、血小板聚集,血管内纤维蛋白原沉积为主,B组血中6-K-PGF_1α增高明显、全血粘度下降,病理改变以血管扩张为著,程度淤血,未见透明血栓。从而推测清栓酶之所以具有去纤、溶栓、扩血管、改善微循环等作用与血中前列腺毒的增高等因素有关。     

Sodium Perchlorate Effects on the Helical Stability of a Mainly Alanine Peptide

Sodium perchlorate salt (NaClO₄) is commonly used as an internal intensity standard in ultraviolet resonance Raman (UVRR) spectroscopy experiments. It is well known that NaClO₄ can have profound effects on peptide stability. The impact of NaClO₄ on protein stability in UVRR experiments has not yet been fully investigated. It is well known from experiment that protein stability is strongly affected by the solution composition (water, salts, osmolytes, etc.). Therefore, it is of the utmost importance to understand the physical basis on which the presence of salts and osmolytes in the solution impact protein structure and stability. The aim of this study is to investigate the effects of NaClO₄, on the helical stability of an alanine peptide in water. Based upon replica-exchange molecular dynamics data, it was found that NaClO₄ solution strongly stabilizes the helical state and that the number of pure helical conformations found at room temperature is greater than in pure water. A thorough investigation of the anion effects on the first and second solvation shells of the peptide, along with the Kirkwood-Buff theory for solutions, allows us to explain the physical mechanisms involved in the observed specific ion effects. A direct mechanism was found in which ClO₄⁻ ions are strongly attracted to the folded backbone.     

Identification of two novel missense WFS1 mutations,H696Y and R703H,in patients with non-syndromic low-frequency sensorineural hearing loss

Non-syndromic low-frequency sensorineural hearing loss(LFSNHL) is an unusual type of hearing loss in which frequencies≤2000 Hz predominantly are affected.To date,different mutations in two genes,DIAPH1 and WFS1,have been found to be associated with LFSNHL. Here,we report a five-generation Chinese family with postlingual and progressive LFSNHL.We mapped the disease locus to a 2.5 Mb region on chromosome 4p16 between markers SNP_A-2167174 and D4S431,overlapping with the DFNA6/14/38 locus.Sequencing of cand...     

Stable nuclear transformation of rhodophyte species Porphyridium purpureum: advanced molecular tools and an optimized method

Photosynthesis Research - A mutated phytoene desaturase (pds) gene, pds-L504R, conferring resistance to the herbicide norflurazon has been reported as a dominant selectable marker for the genetic...