A mathematical model of volatile release in mouth from the dispersion of gelled emulsion particles.

This paper presents a mathematical model of in-mouth volatile release from gelled emulsion particles dispersed in a continuous aqueous phase. Data based on APCI MS-Breath analysis is presented to demonstrate the effect of particle size, oil content and oil-water partition coefficients. It is shown that in-mouth release of aroma from the dispersion of gelled emulsion particles follows a two-component kinetic equation with fast and slow components. Both the fast and slow rate constants depend on the particle size, oil content and oil water partition coefficient of the aroma. The relative amount of aroma contributing to the fast and slow components also depends on the size of the particles. In order to understand this unexpected behaviour, an analytical model was developed that considers the interplay between the mass transfer of flavour across the interface of the particles and that across the air-liquid interface. Analytical expressions for the two rate constants and the relative ratio of aroma contributing to the fast component have been derived. From this model, three regimes of in-mouth release of aroma from the dispersion of gelled emulsion particles were identified including, the emulsion regime, the transition regime and the gel particle regime. In the emulsion regime, changes in the size of gelled emulsion particles had negligible impact on the overall release. In the transition regime, the release was controlled by the interaction of flavour transfer from the particles with that across the air-water interface. In the gel particle regime, aroma release at long times was governed by the particles and that at short times was governed by the air-water interface, and the two processes were fully decoupled. A simple relationship was derived for the critical size above which the release of aroma from the dispersion of gelled emulsion particles is affected by the size of the particles.     

胰岛素样生长因子1对新生大鼠缺氧缺血性脑损伤保护机制的研究

目的　建立单侧缺氧缺血性脑损伤 (HIBD)动物模型 ,研究胰岛素样生长因子 1(IGF 1)对HIBD的影响和可能机制。　方法　选择健康 7日龄Wistar大鼠 12 0只 ,建立HIBD模型 ,随机分成假手术组、HIBD组、HIBD后 0 .2mg/kg人基因重组IGF 1干预组 (RH IGF 1组 )、0 .0 6 6mg/kg人基因重组IGF 1干预组 (SRH IGF 1组 )及盐水对照组 (对照组 )。各组按观察时段进一步分为 2 4、4 8、72h组 ,每组 8只。各组于规定时刻观测脑形态学改变、谷氨酸 (Glu)含量、凋亡细胞计数、Bcl 2蛋白表达。　结果　 (1)HIBD 4 8h组Glu(116 2 .2± 10 8.1)mg/kg ,较假手术组(75 0 .9± 5 3.4 )mg/kg明显升高 (P <0 .0 5 ) ;HIBD组凋亡细胞计数 [2 4h :(7.6± 1.9) % ,4 8h(12 .6±1.2 ) % ,72h :(13.8± 0 .9) % ],较假手术组 [2 4h(2 .0± 0 .2 ) % ,4 8h(2 .0± 0 .3) % ,72h(2 .0±0 .2 ) % ]明显增加 (P均 <0 .0 5 )。 (2 )与对照组相比 ,RH IGF 1组脑组织病变减轻 ;干预 4 8h组Glu[SRH IGF 1组 (781.4± 5 4 .2 )mg/kg ,RH IGF 1组 (74 0 .5± 4 6 .6 )mg/kg],较对照组 (112 6 .6± 4 8.0 )mg/kg明显降低 (P均 <0 .0 5 ) ;RH IGF 1组凋亡细胞计数 [2 4h :(3.6± 0 .9) % ,4 8h(8.2± 2 .2 ) % ,72h(9.4± 1.4 ) % ],较对     

蛋白酶对降低异常精液粘稠度的实验对比研究

目的通过不同蛋白酶类对降低高粘稠度精液的粘稠度效果对比,寻找理想的降低精液粘稠度的药物。方法将高粘稠度精液标本分为两组,A组:31例采用α-糜蛋白酶降低精液粘稠度:B组:32例采用尿激酶降低精液粘稠度;两组均观察用药前后的精子活动力。采用配对t检验和单因素方差分析对所得数据作统计学处理。结果高粘稠度精液用药物(α-糜蛋白酶或者尿激酶)液化精液后,精子的活动力较用药前有明显提高(P<0．001);用药前后精液的粘稠度都存在着明显的差异,精液的粘稠度分别下降44．83％和55．45％(P<0．001);在A组和B组的对比研究中,单因素方差分析检验提示:用药后两组间粘稠度数据有显著的差异(P<0．001￡(?)。结论蛋白酶可以有效地降低异常精液粘稠度的精液,从实验结果提示尿激酶降低精液粘稠度的效果优于α-糜蛋白酶,这有助于临床开展应用性研究和治疗。     

TCD观察动脉瘤性SAH后脑血管痉挛的血流动力学改变

目的探讨动脉瘤性蛛网膜下腔出血(SAH)后脑血管痉挛的血流动力学改变。方法经CT、DSA证实为动脉瘤性SAH患者179例,床旁经颅超声多谱勒(TCD)在术前、术后1~3d、5~7d、9~11d、12~14d记录并分析大脑中动脉(M CA)的血流参数及频谱改变。结果M CA平均血流速度(Vm)于SAH后1~3d开始升高,5~7d、9~11d达到高峰;L I(血管痉挛指数)为3~6时预后良好;>6时可以出现神经系统功能损害,颅内压增高且有脑血管痉挛(CV S)者预后较差。结论TCD能无创、实时评价SAH后CV S的动态变化,可以推断SAH后CV S的严重程度及临床转归。     

血管内皮生长因子与妊娠高血压综合征发病的关系

目的　探讨血管内皮生长因子 (VEGF)在妊娠高血压综合征发病中的作用。方法　分别采用酶联免疫吸附试验检测 40例妊高征孕妇的血清VEGF水平 ,免疫组化检测胎盘及蜕膜组织VEGF及CD3 4表达情况 ,35例正常孕妇作对照。结果　①妊高征组孕妇的外周血VEGF水平及胎盘组织MVD明显低于正常妊娠组 (P <0 0 5 ) ;②两组胎盘绒毛滋养叶细胞和蜕膜组织中均有VEGF阳性表达 ,胎盘组织强阳性表达高于蜕膜。与对照组比较 ,其胎盘组织VEGF强阳性表达的轻度妊高征无显著性差异 ;而中度和重度妊高征与对照组相比 ,则明显降低 ,差异显著 (P <0 0 5 )。各组孕妇蜕膜组织中VEGF的表达强度和差异无显著性。③孕妇外周血VEGF水平与新生儿出生体重 (r =0 2 9,P <0 0 5 )和胎盘重量 (r =0 34,P <0 0 1)均存在直线正相关关系。结论　妊高征患者血清VEGF水平和胎盘组织MVD降低 ,胎盘组织VEGF表达明显下降 ,都可能在妊高征的发病中起一定的作用。     

Association of the expressions of platelet-derived growth factor receptor and c-Fos with the biological characteristics of bladder cancer.

OBJECTIVE: To elucidate the relation of platelet-derived growth factor receptor (PDGFR) and c-Fos protein expressions with human bladder transitional epithelial cell carcinoma (BTCC). METHODS: The expressions of PDGFR and c-Fos were investigated in 11 normal bladder tissue samples, 14 adjacent non-carcinoma tissues and 43 BTCC tissues by means of SP immunohistochemical technique. RESULTS: The c-Fos expression was found in the cell nuclei and cytoplasm, and PDGFR in the nuclear membrane, cytoplasm, and cellular membrane. PDGFR and c-Fos were detected in 81.40% and 48.83% of the BTCC tissues respectively, at the rates both significantly higher than those in normal and adjacent non-carcinoma tissues (P<0.05). Correlation between the expression of c-Fos and the tumor grading was noted (P<0.05). The expressions of PDGFR and c-Fos in tumor blood vessels were significantly higher than those in normal vessels. CONCLUSIONS: The expressions of PDGFR and c-Fos might be involved in the development of BTCC, possibly related to the angiogenesis of the tumors. c-Fos expression can indicated the cell proliferative status of the BTCC.     

颈动脉狭窄在脑保护装置下的支架置入治疗

目的探讨颈动脉狭窄患者支架治疗中的脑保护装置的有效性和安全性及治疗意义。方法对14例颈动脉狭窄患者进行血管内支架治疗。全部应用了脑保护装置(滤网型)。结果14例患者成功地释放了18枚自膨式支架。其中2例发生微栓子脱落轻度卒中,治疗1～3d完全恢复,颈动脉狭窄6例出现短暂性心率减慢和低血压。随访期所有患者均未发生脑梗死。结论在支架治疗中,脑保护装置的应用可减少治疗中的神经并发症,是一种有效和安全的治疗方法。     

腹腔镜胆总管切开取石术后内置管引流与T管引流临床研究

目的 :比较分析腹腔镜胆总管切开取石术后内置管引流与T管引流两种方法对患者康复的影响。方法 :回顾性总结分析 1999年以来行腹腔镜胆总管切开取石术后内置管引流的 2 6例患者临床疗效 ,并与同期行T管引流的 31例患者进行了比较。结果 :内置管引流组术后无胆汁丢失 ,较T管引流组痛苦小、胃肠功能恢复快。两组比较 ,手术时间无明显差异 ,术后开始进食时间分别为 13.8± 3.4,35 .5± 6 .8h ,(P <0 .0 5 ) ,恢复肠蠕动时间为 30 .5± 5 .6 ,43.8± 7.4h ,(P <0 .0 5 ) ,抗生素平均使用天数 3.5± 0 .6 ,6 .4± 1.1d ,(P <0 .0 5 ) ,术后输液量 45 5 0± 5 84,135 0 0± 12 5 0ml,(P <0 .0 1) ,术后平均住院日 4.6± 1.7,9.6± 2 .4d ,(P <0 .0 1) ,平均住院费用 815 0± 910 ,5 0 0± 12 70元 (P <0 .0 5 ) ,恢复日常工作时间 12 .8± 2 .5 ,2 7.4± 6 .9d ,(P <0 .0 5 )。结论 :腹腔境胆总管探查、内置管引流术后胆总管一期缝合避免了T管引起的并发症 ,大大减轻了患者的痛苦 ,缩短了输液时间和住院时间 ,减少了抗生素的用量 ,值得推广应用。     

甲醛固定源同种异体骨移植材料的体外实验研究

OBJECTIVE: To conduct an in vitro study to assess the preliminary possibility of using formalin-fixed, instead of fresh, human bone tissues for allografting. METHODS: Fresh cadaveric bone tissues were fixed by formalin for more than 6 months and dissected into 5 mmx5 mmx5 mm pieces and 5 mmx5 mmx40 mm sticks, followed by chemical treatments to prepare the allograft bone materials. When alls treatments were completed, the bone grafts were centrifuged and their properties and cellular compatibility assessed in comparison with the currently used bone grafts clinically. RESULTS: The residual formaldehyde of the fixed allograft bone material was much below the controlled level and no significant differences were noted between the bone graft materials tested in regard to the chemical and mechanical properties and biocompatibility. CONCLUSION: This material we have prepared may meet the clinical demands for bone grafting, with good biocompatibility and less chance for infection by pathological agents.     

Effect of age and caloric restriction on insulin receptor binding and glucose transporter levels in aging rats

We report on the effect of age and chronic caloric restriction (CR) on insulin binding and glucose transporter content in both diaphragm and heart muscle membrane of young (11 months), mid-age (17 months), and old (29 month) ad libitum fed and CR Brown-Norway rats. The control animals received rat chow ad lib and CR animals were allowed 60% of ad libitum food. The CR regimen was initiated at four months of age and the animals were maintained on their respective diets until necropsy. There was no effect of age on insulin binding for either ad libitum or CR animals at each age evaluated. Caloric restriction significantly lowered insulin levels at each age studied when compared to the ad libitum-fed rats. However, CR animals were noted to have increased insulin binding (p < 0.001) compared to ad libitum-fed animals at each age for diaphragm muscle. For the heart, there appeared to be a decreased binding, particularly at higher insulin concentrations, in CR-fed animals. There was no net change in Glut-1 or Glut-4 levels for heart muscle membrane, or Glut-4 levels for diaphragm muscle membrane between ad libitum or CR animals. This data indicates that caloric restriction may have tissue-specific effects for insulin receptor binding, and that the improved insulin sensitivity in CR states is not a result of altered glucose transporter protein content.