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1.
影响冻干制品残余水分的因素很多,但西林瓶胶塞的含水量是其关键因素。使用经干烤工艺处理和未干烤处理的药用溴丁基胶塞进行麻疹减毒活疫苗冻干试验,结果显示,用未经干烤工艺处理及处理的药用溴丁基胶塞冻干的麻疹减毒活疫苗,存储18个月后,水分上升的平均值分别为2.03%和0.08%,经单一因素的方差分析,两者有统计学意义(P0.01)。证明经处理的药用溴丁基胶塞,对保持麻疹减毒活疫苗在存储期内的残余水分稳定作用效果明显。  相似文献   

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不同水分处理对甘蒙柽柳幼苗根系生长特性的影响   总被引:2,自引:0,他引:2  
以1年生甘蒙柽柳幼苗为对象,采用人工壕沟挖掘法,对柽柳幼苗在不同水分处理条件下(干旱处理、适度灌溉、充分灌溉)根系生态学特征的季节变化进行了研究.结果表明,不同水分处理对柽柳幼苗根系生长影响显著,垂直根扎根深度和生长速率随着灌溉量的减小而增加.地面灌溉量的增加会导致根系分布的浅表化和根系消弱系数的减小,根系生物量与土壤深度呈显著负对数关系.不同水分处理条件下,7-10月的根/冠比平均值分别为0.43、0.60、0.90、1.12,其根、冠间存在典型的异速生长关系.根/冠比随土壤水分的减小而增加,且生长季后期大于初期.  相似文献   

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Barley seeds were treated with ethyl methanesulphonate (EMS) for 3 h at 25° C, washed with tap water for 24 h at 25° C, redried at 40° C to different moisture contents below 15% and stored at 25° C in desiccators or in sealed plastic bags. The criteria used for expressing the effect of storage were the M1 seedling height and the frequency of chromosomal aberrations. With 14·9% seed moisture a strong increase of biological injury occurred in the course of a 2-week storage, while storage of seeds having an initial moisture content of 11·7% led to a significant increase of injury only after 6 weeks. Superdry EMS-treated seeds with 5% or less moisture can be stored at 25° C without any changes in the biological effects. A method is recommended to avoid the EMS-storage effects.  相似文献   

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The level of antituberculous immunity seems to be related to the number of memory T cells induced. This may vary as a function of the multiplication and persistence of BCG in host tissues. The most important requirements for a BCG vaccine are, therefore, the immunogenicity of the strain, the high proportion of live to dead bacilli, and adequate dispersion and low levels of soluble antigens. The surface-grown Pasteur BCG vaccine contains a very high proportion of bacilli killed by ball-milling and freeze-drying. It also contains clumps and soluble antigens, all factors influencing cell-mediated immune processes and viability control. Therefore, several batches of vaccine were prepared on an industrial scale using one of the most immunogenic strains (French 1173 P2) and grown as dispersed bacilli by a modified cell type culture method. This method provided fully viable, well-dispersed vaccines which have a viability and heat stability superior to that of the classical surface-grown BCG. The immunogenicity was checked by multiplication and persistence in mouse organs and the skin reactivity and tuberculin hypersensitivity in guinea-pigs showed results comparable to those obtained with classical vaccine. Small-scale tests in children showed superior immunogenicity of the dispersed as opposed to the classical vaccine and there was no suppurative adenitis.  相似文献   

6.

Background and Aims

Great attention has been paid to N2O emissions from paddy soils under summer rice-winter wheat double-crop rotation, while less focus was given to the NO emissions. Besides, neither mechanism is completely understood. Therefore, this study aimed at evaluating the relative importance of nitrification and denitrification to N2O and NO emissions from the two soils at different soil moisture contents

Methods

N2O and NO emissions during one winter wheat season were simultaneously measured in situ in two rice-wheat based field plots at two different locations in Jiangsu Province, China. One soil was neutral in pH with silt loam texture (NSL), the other soil alkaline in pH with a clay texture (AC). A 15?N tracer incubation experiment was conducted in the laboratory to evaluate the relative importance of nitrification and denitrification for N2O and NO emissions at soil moisture contents of 40 % water holding capacity (WHC), 65 % WHC and 90 % WHC.

Results

Higher N2O emission rates in the AC soil than in the NSL soil were found both in the field and in the laboratory experiments; however, the differences in N2O emissions between AC soil and NSL soil were smaller in the field than in the laboratory. In the latter experiment, nitrification was observed to be the more important source of N2O emissions (>70 %) than denitrification, regardless of the soils and moisture treatments, with the only exception of the AC soil at 90 % WHC, at which the contributions of nitrification and denitrification to N2O emissions were comparable. The ratios of NO/N2O also supported the evidence that the nitrification process was the dominant source of N2O and NO both in situ and in the laboratory. The proportion of nitrified N emitted as N2O (P N2O ) in NSL soil were around 0.02 % in all three moisture treatments, however, P N2O in the AC soil (0.04 % to 0.10 %) tended to decrease with increasing soil moisture content.

Conclusions

Our results suggest that N2O emission rates obtained from laboratory incubation experiments are not suitable for the estimation of the true amount of N2O fluxes on a field scale. Besides, the variations of P N2O with soil property and soil moisture content should be taken into account in model simulations of N2O emission from soils.  相似文献   

7.
冻干人用狂犬病纯化疫苗的研制   总被引:3,自引:0,他引:3  
在以原代地鼠肾细胞培养生产狂犬病疫苗工艺的基础上,通过对病毒收获液的浓缩倍数、灭活方式的改进及优化、冻干稳定剂的筛选、冻干曲线的确立,制备出了冻干疫苗,其质量及稳定性较液体疫苗有了整体水平的提高,各项检定结果均符合《中国生物制品规程》(2000版)。  相似文献   

8.
应用旋转培养的方法,建立冻干水痘减毒活疫苗的生产工艺。选择长成致密单层的2BS细胞,接种带状疱疹病毒Oka株,待细胞病变达75%以上时,收获病毒液,经超声破碎、离心、澄清,冻干后,按常规检定,疫苗各项检定符合《WHO水痘活疫苗规程》及《冻干水痘减毒活疫苗制造及检定试行规程》要求。与克氏瓶相比,应用旋转培养,不但提高了疫苗单产,降低了牛血清蛋白残留量,而且疫苗质量也保持稳定。  相似文献   

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冻干人用狂犬病纯化疫苗稳定剂的筛选   总被引:1,自引:0,他引:1  
取同一批人用狂犬病纯化疫苗纯化液,分别加入筛选出的A、B、C和D稳定剂,按已确定的适宜冻干曲线进行冻干后,分别检测其安全、效力、外观、水分等,效力结果显示,使用A、B、D稳定剂的制品在37℃放置3个月,效价降低了48%~60%;使用C稳定剂的制品在37℃放置3个月效价仅下降了16.1%。表明C稳定剂为冻干人用狂犬病纯化疫苗适宜的稳定剂配方。  相似文献   

11.
影响生物制品冻干粉针剂水分的探讨   总被引:3,自引:0,他引:3  
探讨生物制品冻干粉针剂样品放置一时间后残余水分增高的原因。进行了水分测定,真空度检测,二甲硅油和丁基橡胶药用瓶塞干燥失重的检测。冻干后每只丁基橡胶药用瓶塞平均含水分0.00224g。结果表明丁基橡胶药用瓶塞灭苗,干燥和冻干过程中去除水分不彻底是引起样品中水分升高的直接原因。  相似文献   

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目的为皮上划痕人用布氏菌活疫苗筛选存活率高、无明胶冻干稳定剂。方法以冻干活菌存活率为指标,对甘油、甘露醇、蔗糖、葡萄糖、乳糖、谷氨酸钠、甘氨酸、谷氨酸、脯氨酸和硫脲等10种稳定剂通过单因素筛选法,筛选出冻干存活率高的4种单因素稳定剂成分;将4种单因素稳定剂成分进行正交试验优化,筛选出最优稳定剂组合。结果单因素试验结果显示,甘油、葡萄糖、谷氨酸钠和硫脲4种稳定剂成分冻干后活菌存活率较高,对布氏菌活疫苗具有良好保护效果。通过正交试验筛选出最优稳定剂配方中四组分的质量分数分别为甘油1.5%、葡萄糖5%、硫脲1.5%、谷氨酸钠1.0%,该配方的冻干存活率可达81.5%。结论无明胶冻干稳定剂对布氏菌活疫苗具有较好的保护作用。  相似文献   

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Previous studies have demonstrated that the water content of freeze-dried vaccines increases during storage. The reasons for these variations in water content are discussed in this paper. Different possible mechanisms have been considered: microleakages at the closure sealing point, water vapour transfer through the closure (permeation, loss and uptake of water by the stopper). Several types of vials and closures were studied, under different conditions of storage. Regardless of the vial form selected, the probability of microleakages was low. The stopper would seem to play an important role in the water transfer mechanisms. The moisture content of the stopper determines its equilibrium relative humidity (ERH) and whether there will be moisture transfer between the stopper and the vial contents and between the stopper and the storage atmosphere.  相似文献   

15.
J C May  R M Wheeler  E Grim 《Cryobiology》1989,26(3):277-284
The gravimetric test for the determination of residual moisture in freeze-dried biological products performed in a humidity- and temperature-controlled room with the use of scrupulous gravimetric analytical technique can be used to accurately determine residual moisture in freeze-dried biological products such as antihemophilic factor (human) or honey bee venom allergenic extract. This method determines the first water of hydration of sodium tartrate dihydrate (7.93%) to within 1.3% of the calculated value with a relative standard deviation of 0.3% for 10 replicates. For this gravimetric procedure, freeze-dried samples containing from 1.12 to 4.4% residual moisture had relative standard deviations ranging from 3.6 to 9.1%. Samples containing less than 1.0% residual moisture by the gravimetric method such as intravenous immune globulin and antihemophilic factor (human) had relative standard deviations ranging from 16.7 to 47.0%. Relative standard deviations for residual moisture tests performed on comparable samples by the Karl Fischer and thermogravimetric methods showed similar variability.  相似文献   

16.
为选择合适的的冻干A、C群脑膜炎球菌结合疫苗的稀释液,以注射用水(H2O)、生理盐水(NS)、磷酸盐缓冲液(PBSpH6.8~7.2)作为候选稀释液,进行了相关溶解度、pH、渗透压、异常毒性、免疫原性的检测比较。溶解度、pH、免疫原性结果显示三种稀释液无差异;H2O作为稀释液的渗透压不符合人用制剂渗透压的要求,另两者则符合要求;三种稀释液溶解制品后的pH检测数据均符合要求,但PBS的缓冲能力更强。故认为PBS更适合作为冻干A、C群脑膜炎球菌结合疫苗的稀释液。  相似文献   

17.
Bouma  Tjeerd J.  Bryla  David R. 《Plant and Soil》2000,227(1-2):215-221
Estimates of root and soil respiration are becoming increasingly important in agricultural and ecological research, but there is little understanding how soil texture and water content may affect these estimates. We examined the effects of soil texture on (i) estimated rates of root and soil respiration and (ii) soil CO2 concentrations, during cycles of soil wetting and drying in the citrus rootstock, Volkamer lemon (Citrus volkameriana Tan. and Pasq.). Plants were grown in soil columns filled with three different soil mixtures varying in their sand, silt and clay content. Root and soil respiration rates, soil water content, plant water uptake and soil CO2 concentrations were measured and dynamic relationships among these variables were developed for each soil texture treatment. We found that although the different soil textures differed in their plant-soil water relations characteristics, plant growth was only slightly affected. Root and soil respiration rates were similar under most soil moisture conditions for soils varying widely in percentages of sand, silt and clay. Only following irrigation did CO2 efflux from the soil surface vary among soils. That is, efflux of CO2 from the soil surface was much more restricted after watering (therefore rendering any respiration measurements inaccurate) in finer textured soils than in sandy soils because of reduced porosity in the finer textured soils. Accordingly, CO2 reached and maintained the highest concentrations in finer textured soils (> 40 mmol CO2 mol−1). This study revealed that changes in soil moisture can affect interpretations of root and soil measurements based on CO2 efflux, particularly in fine textured soils. The implications of the present findings for field soil CO2 flux measurements are discussed. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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将现行伤寒多糖疫苗和A群脑多糖疫苗各1人份,联合后以乳糖为保护剂冻干,制备成1人份二联冻干疫苗。并对该疫苗进行鉴别试验、伤寒Vi多糖含量测定、A群流脑多糖磷含量测定、安全试验、冻干二联苗与单价苗Sepharose CL-4B柱层析图比较以及免疫保护效果、动物血清抗体滴度和稳定性试验。试验初步表明,该二联多糖疫苗是安全的,混合后不会引起各自的主要成份、免疫保护效果和抗体应答水平发生变化。即相互没有干扰。一年后各项指标检测表明稳定性良好。可以作为二联苗接种同时预防伤寒和A群汉脑所引起的传染。  相似文献   

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