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121.
采用普米克气雾吸入治疗 48例咳嗽变异型哮喘患者。结果表明 :治疗组气道高反应性显著降低 (P <0 .0 0 1) ,肺功能显著改善 ( P <0 .0 0 1) ,与对照组比较差异有显著性 ( P <0 .0 1)。证实普米克吸入对改善咳嗽变异型哮喘病人肺功能及降低气道高反应性疗效肯定 ,有积极意义 相似文献
122.
目的:研究安乃近溶液弄粘膜吸收规律。方法:以大鼠在体鼻循环法为实验模型,考察循环液的体积、流速等对安乃近弃枯膜吸收的影响。并在体积、流速确定的条件下,考查循环液浓度不同时,安乃近鼻粘膜吸收规律。结果:循环液体积越大,单位时间内粘膜吸收百分率越小;当流速较小时,随着流速的增加,吸收速度常数K增大,流速超过2 . 0 ml · min-1后,K显著减小;以循环液体积为3 ml,流速2.0 ml"min-1,考察了50,100,150,200 g·L-1安乃近溶液弄粘膜吸收规律,表明不同浓度的安乃近鼻粘膜吸收速度为一常数。结论:安乃近溶液鼻粘膜吸收机制为被动扩散,吸收符合一级动力学,吸收速度常数K为0.022 19 min-1 。 相似文献
123.
Marttin Emmeline Verhoef J. Coos Cullander Christopher Romeijn Stefan G. Nagelkerke J. Fred Merkus Frans W. H. M. 《Pharmaceutical research》1997,14(5):631-637
Purpose. To visualize the transport pathway(s) of high molecular weight model compounds across rat nasal epithelium in vivousing confocal laser scanning microscopy. Furthermore, the influence of nasal absorption enhancers (randomly methylated -cyclodextrin and sodium taurodihydrofusidate) on this transport was studied.
Methods. Fluorescein isothiocyanate (FITC)-labelled dextrans with a molecular weight of 3,000 or 10,000 Da were administered intranasally to rats. Fifteen minutes after administration the tissue was fixed with Bouin. The nasal septum was surgically removed and stained with Evans Blue protein stain or DiIC18(5) lipid stain prior to visualization with the confocal laser scanning microscope.
Results. Transport of FITC-dextran 3,000 across nasal epithelium occurred via the paracellular pathway. Endocytosis of FITC-dextran 3,000 was also shown. In the presence of randomly methylated -cyclodextrin 2% (w/v) similar transport pathways for FITC-dextran 3,000 were observed. With sodium taurodihydrofusidate 1% (w/v) the transport route was also paracellular with endocytosis, but cells were swollen and mucus was extruded into the nasal cavity. For FITC-dextran 10,000 hardly any transport was observed without enhancer, or after co-administration with randomly methylated -cyclodextrin 2% (w/v). Co-administration with sodium taurodihydrofusidate 1% (w/v) resulted in paracellular transport of FITC-dextran 10,000, but morphological changes, i.e. swelling of cells and mucus extrusion, were observed.
Conclusions. Confocal laser scanning microscopy is a suitable approach to visualize the transport pathways of high molecular weight hydrophilic compounds across nasal epithelium, and to study the effects of absorption enhancers on drug transport and cell morphology. 相似文献
124.
嗅神经上皮瘤的临床病理分析 总被引:1,自引:0,他引:1
分析嗅神经上皮瘤(嗅神经母细胞瘤)的临床、病理特点,探讨免疫组化技术和电镜在嗅神经上皮瘤诊断中的应用价值。方法对19例嗅神经上皮瘤进行了临床分析,光镜复查,免疫组化检测,4例做了透射电镜观察。结果嗅神经上皮瘤主要发生于中青年,起病缓慢,首发症状以单侧鼻塞和鼻出血为多见,病理形态为小圆细胞和短梭形细胞呈巢状及弥散分布,菊形团结构少见或缺如;免疫组化检测NSE、Syn阳性,CK、S-100等部分阳性,GFAP阴性;电镜超微结构2例在胞质内找到神经分泌颗粒,3例在胞质内发现中间丝、微丝和基膜,1例有细胞连接和神经突起。结论嗅神经上皮瘤这个名称较嗅神经母细胞瘤更确切,诊断除常规病理外,尚需借助于免疫组化检测,分化差的病例只能通过电镜或其他先进的手段来解决。 相似文献
125.
Wood dust is an irritant and is carcinogenic to the nasal mucosa. It inhibits its own clearance from the nose. It therefore makes sense to lavage retained wood dust from the nose following exposure. To our knowledge this is the second study conducted to determine whether the procedure of nasal lavage reduces nasal symptoms in woodworkers. Forty-six woodworkers from 150 approached volunteered to trial nasal lavage using gravity fed, home-made unbuffered isotonic saline for 2 months in a crossover trial and then be followed-up a year later. The group reported significantly decreased nasal symptoms and over half continued to use nasal lavage voluntarily after 1 year. Results support the findings of the previous study that nasal lavage improves nasal symptoms and supplements those findings with data indicating patterns of voluntary usage following the study's conclusion. It is concluded that nasal lavage is an acceptable, effective and inexpensive option with minimal side effects for woodworkers who experience nasal symptoms and who wish to try the procedure. 相似文献
126.
Summary The effects of cocaine on the contractile response of isolated human nasal mucosal blood vessels to field stimulation and methoxamine were investigated. Results showed that cocaine antagonized methoxamine and inhibited field stimulation. The drug increased resting tension in human nasal mucosa in vitro through direct actions and potentiated mucosal contractions by norepinephrine and epinephrine. The study indicated that high concentrations of cocaine may actually antagonize -adrenoceptors, but these concentrations are not necessary in eliciting desired degrees of vasoconstriction in nasal blood vessels while being applied as a local anesthetic. 相似文献
127.
Absorption Enhancing Effect of Cyclodextrins on Intranasally Administered Insulin in Rats 总被引:4,自引:0,他引:4
Merkus Frans W. H. M. Verhoef J. Coos Romeijn Stefan G. Schipper Nicolaas G. M. 《Pharmaceutical research》1991,8(5):588-592
The absorption enhancing effect of -, -, and -cyclodextrin (CD), dimethyl--cyclodextrin (DMCD), and hydroxypropyl--cyclodextrin (HPCD) on intranasally administered insulin was investigated in rats. Coadministration of 5% (w/v) DMCD to the insulin solution resulted in a high bioavailability, 108.9 ± 36.4% (mean ± SD, n = 6), compared to i.v. administration, and a strong decrease in blood glucose levels, to 25% of their initial values. Coadministration of 5% -CD gave rise to an insulin bioavailability of 27.7 ± 11.5% (mean ± SD, n = 6) and a decrease in blood glucose to 50% of its initial value. The rate of insulin absorption and the concomitant hypoglycemic response were delayed for the -CD-containing solution as compared to the DMCD preparation. The other CDs, HPCD (5%), -CD (1.8%), and -CD (5%), did not have significant effects on nasal insulin absorption. DMCD at a concentration of 5% (w/v) induces ciliostasis as measured on chicken embryo tracheal tissue in vitro, but this effect is reversible. In conclusion, DMCD is a potent enhancer of nasal insulin absorption in rats. 相似文献
128.
喷雾干燥对溶菌酶一级结构的影响 总被引:1,自引:1,他引:1
目的 考察喷雾干燥对溶茵酶一级结构稳定性的影响。方法 以送料速度2.4 ml/min、进口气流温度150℃、出口气流温度70℃、雾化器转速18 000 r/min制备喷雾干燥溶茵酶。采用MALDI-TOF/MS测定喷雾干燥对溶菌酶一级结构的影响。结果 喷雾干燥溶菌酶除了具有溶菌酶相同的准分子离子峰、二聚体、三聚体、四聚体及三聚体的两电荷离子峰外,另多5个碎片离子峰。结论 喷雾干燥可造成溶菌酶一级结构破坏。 相似文献
129.
雪荔颗粒喷雾干燥法制备的工艺优化 总被引:4,自引:0,他引:4
采用正交试验法,选定药液密度、进液速度和进风温度3因素,筛选雪荔颗粒喷雾干燥的最佳工艺。最佳工艺为药液密度1.07mg/ml(热测法),进液速度9ml/min,进风温度176℃。 相似文献
130.
功能性鼻内镜鼻窦手术后术腔清理(附1080例临床分析) 总被引:3,自引:1,他引:3
目的:探讨功能性鼻内镜鼻窦手术后术腔清理对鼻窦结构及上皮功能恢复的影响。方法:1080例均为采取Messerklinger术式完成功能性鼻内镜鼻窦手术的病例。手术后2周进行第一次鼻腔鼻窦清理,以后每隔2周一次,共进行4或4次以上清理至术腔基本上皮化。结果:112例手术后1个月术腔基本上皮化,456例手术后2个月术腔基本上皮化,255例手术后3个月术腔基本上皮化;98例出现术后窦口闭锁,176例出现术腔粘连,在术腔清理过程中进行处理,这些并发症均消失;95例出现术后复发而需要进一步手术治疗。结论:术腔粘膜的再上皮化对功能性鼻内镜鼻窦手术后鼻窦功能的恢复至关重要,这一过程一般需要1~3个月甚至更长时间,手术后规范化的术腔清理能早期发现并处理粘膜病变、术腔狭窄及窦口阻塞,因而术后清理对提高功能性鼻内镜鼻窦手术的疗效有重要价值。 相似文献