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901.
双歧杆菌制剂对腹泻动物保护作用的观察   总被引:3,自引:1,他引:2  
实验证明四联双歧活菌制剂大、中剂量对腹泻动作用达71.2%,小剂量为57.1%,3个剂量组都无动物死亡,而氟哌酸治疗组保护作用为28.6%,生理盐水治疗组为14.3%,死亡率分别为14.3%和28.6%,这提示双歧四联活菌制剂在维持宿主的正常免疫功能和提高定植抗力方面具重要作用。  相似文献   
902.
A comparison was made between a vertical tube rotor and a fixed angle rotor for isopycnic centrifugation of proteoglycans. In the vertical tube rotor, isopycnic gradient was achieved much faster than in the conventional fixed angle rotor. The use of a vertical tube rotor for isopycnic centrifugation shortens the time considerably for the isolation of proteoglycans fron various tissues.  相似文献   
903.
This technical note and its corresponding video show the procedure for optimal sample preparation to perform wood and phloem formation analyses.  相似文献   
904.
利用SiO2纳米微粒实现细胞分离技术的关键就是如何制备粒径为15~20mm,纯度高,比表面积大,吸附性好,结构为无定型的SiO2纳米微粒.以硅酸钠、硫酸为原料,采用一步法直接制备得到细胞分离用SiO2纳米微粒,探讨了制备条件对SiO2纳米微粒性能的影响,确立了最优化的制备条件.  相似文献   
905.
以单因素试验为基础,采用正交实验设计优化制备朝鲜蓟(Cynara scolymus)提取物颗粒剂的最佳工艺条件。以原料与辅料配比、原料药比例、乙醇浓度及干燥温度为考察因素,以颗粒合格率、溶化时间作为评价指标,采用L9(34)正交试验分别对颗粒合格率、溶化时间进行直观分析及方差分析。结果表明,最佳成型工艺为乳糖:糊精=3:1,乙醇浓度60%,原料药比例7.0%,干燥温度50 ℃。按此方案进行验证实验,颗粒性状良好,颗粒合格率为91.45%,含水量4.90%,减失重量不超过2.0%,溶解时间85.67 s,均符合2020年中国药典有关规定。通过正交试验优选的颗粒剂制备工艺稳定、简便易行,为朝鲜蓟提取物的剂型开发及工业化生产颗粒剂提供理论依据。  相似文献   
906.
907.
While pulsed field gel electrophoresis has become an important tool for genotyping of bacteria, one of its drawbacks is that standard methods are rather time-consuming. In order to overcome this problem, shortened procedures for DNA preparation have been developed for some bacterial species. The aim of this study was to examine if a short procedure used for pulsed field gel electrophoresis of Clostridium botulinum could be applied to other Clostridia species. For this, the protocol was modified and used to prepare the DNA of 34 strains of 25 different Clostridia species. In contrast to a standard procedure, which takes at least 5 days from DNA extraction to completion of the electrophoresis, this protocol yielded results within 2 days. In order to directly compare the results of the short protocol with those of the standard, long procedure, parallel DNA preparations were performed using both methods and the two DNA samples thus obtained per strain were then run on the same gel. Briefly, the procedure was as follows. After embedding the bacterial cells in agarose, the agarose blocks were incubated for 1 h in lysis solution containing lysozyme, mutanolysin, lysostaphin and RNase. This was followed by a 1-h proteinase K treatment. Then, slices were cut from the agarose blocks and washed for 15 min in TE buffer, these washes were repeated four times with fresh TE. After a 2-h restriction with SmaI, electrophoresis was carried out overnight.  相似文献   
908.
We studied the effects of in vitro treatment of differentiating osteogenic cells with FMS*Calciumfluor, to determine whether it caused changes in proliferative or differentiation potential of osteoblasts. FMS*Calciumfluor was developed for the therapy of post-menopausal and age-related osteoporosis on the basis of the principles of resonance homeopathy and VTR Vega test. Its daily prescribed therapeutical usage is about 30,000-fold less in fluoride concentration than that recommended for NaF associated with calcium monophosphate. Rat tibial osteoblast (ROB) primary cultures represent populations of early osteoblasts and their derivative cultures of more than 60 cumulative population doubling (CPD) represent more mature osteogenic cells. Both these populations were shown to undergo in vitro differentiation, as monitored by the sequential expression of markers that define the stages of the osteogenic progression. Here we report that continual treatment of ROB during osteogenesis with FMS*Calciumfluor modulated the expression of critical osteogenic markers: alkaline phosphatase (AP), an indicator of osteoblast maturation, and(45)Ca incorporation into the matrix and nodule formation, events of the last phase of osteogenesis and a measure of osteoid mineralization. Treatment did not affect proliferation, or expression and activation of metalloproteinases (MMP). AP activity and levels of AP mRNA were increased by treatment with FMS*Calciumfluor; the incorporation of radiolabelled Ca into the matrix was also increased and the formation of nodules occurred in a shorter time and with higher frequency than in untreated control cultures. The effects of FMS*Calciumfluor were concentration dependent and specific for its modalities of preparation, and were observed at a concentration about three orders of magnitude lower than similar effects reported in the literature by treatment of osteoblast cultures in vitro with NaF.  相似文献   
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