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111.
112.
Takeo Miyamae 《Microbiology and immunology》1994,38(12):937-941
The protective effects in mice by nasal vaccination of amine- and amide-inactivated Sendai viruses were investigated by a contact exposure experiment, immunofluorescent examination of the entire respiratory tract, and checking the serum HI antibody development. Of 10 monoamines, ethanolamine and 2-methoxyethylamine vaccines induced complete protection, and methylamine, ethylamine, n-propylamine, n-butylamine, 2-ethoxyethylamine, diethylamine and triethylamine vaccines brought about almost complete protection or lower respiratory infection. The methoxyamine-treated mouse conferred the least protection. Of 5 diamines, 1, 3-diaminopropane vaccine inhibited completely the infection, but hydrazine, ethylenediamine, putrescine, and cadaverine vaccines produced regional infection. Two polyamines, spermine and spermidine, did not inactivate the virus. Of 4 amides, only semicarbazide vaccine conferred complete mucosal defense, while acetamide, propionamide, and isonicotinic acid hydrazide vaccines lead to regional infection. Serum HI titers developed by vaccination were low on the whole, following their slight rise, fall or maintenance postexposure. In effect, the 4 vaccines inactivated by a best-suited interstrand crosslink between phosphate groups in helix of viral RNA brought about the strongest protection, and showed the necessity of a definite length of molecules for inactivants. 相似文献
113.
Single ATP-sensitive potassium channels (K
ATP channels) were studied in inside-out membrane patches excised from mouse skeletal muscle. Channel blockage by the non-hydrolysable ATP analogue AMP-PNP was investigated in the absence or presence of 1 mM MgCl2 with K+-rich solutions bathing the internal membrane surface. Currents through single. K
ATP channels were recorded at –40 and +40 mV AMP-PNP (5 to 500 M; Li salt) reduced the open-probability po of K
ATP channels and decreased the single-channel currents at high nucleotide concentrations by approximately 10%. Half maximal reduction of po at –40 mV was observed at nucleotide concentrations of 29 M in the absence and of 39 M in the presence of Mg2+. The steepness of the AMP-PNP concentration-response curves was strongly affected by Mg2+, the Hill coefficients of the curves were 0.6 in the absence and 1.6 in the presence of 1 mM MgCl2. The efficacies of channel blockage by AMP-PNP at –40 and +40 mV were not significantly different. The results indicate that a K
ATP channel can bind more divalent Mg2+-complexes of AMP-PNP than trivalent protonated forms of the nucleotide and that channel blockage is hardly affected by the membrane electric field. To estimate the contribution of lithium ions to the observed results, we studied the effects of LiCl (0.8 to 10 mM) in the Mg2+-free solution on the single channel current i. At a Li+ concentration of 10 mM, i was hardly affected at –40 mV but reduced by a factor of 0.75 at +40 mV. The results are interpreted by a fast, voltage-dependent blockage of K
ATP channels by internal Li+ ions.
Correspondence to: B. Neumcke 相似文献
114.
Kiao Inthavong Kai Zhang 《Computer methods in biomechanics and biomedical engineering》2013,16(7):633-643
Recent advances in nanotechnology have seen the manufacture of engineered nanoparticles for many commercial and medical applications such as targeted drug delivery and gene therapy. Transport of nanoparticles is mainly attributed to the Brownian force which increases as the nanoparticle decreases to 1 nm. This paper first verifies a Lagrangian Brownian model found in the commercial computational fluid dynamics software Fluent before applying the model to the nasal cavity and the tracheobronchial (TB) airway tree with a focus on drug delivery. The average radial dispersion of the nanoparticles was 9x greater for the user-defined function model over the Fluent in-built model. Deposition in the nasal cavity was high for very small nanoparticles. The particle diameter range in which the deposition drops from 80 to 18% is between 1 and 10 nm. From 10 to 150 nm, however, there is only a small change in the deposition curve from 18 to 15%. A similar deposition curve profile was found for the TB airway. 相似文献
115.
Despite centuries of investigation, the function of the maxillary sinus (MS) and underlying patterns governing its form remain elusive. In this study, we articulate a methodology for collecting volumetric data for the MS and nasal cavity (NC) from computed tomography (CT) scans and report details for a small sample of 39 dried human crania of known ecogeographic provenience useful for assessing variation in MS size and shape. We use scaling analyses to preliminarily test the hypothesis that volumes of the nasal cavity (NCV) and maxillary sinus (MSV) are inversely correlated such that the NC covaries with size of the face, whereas the MS "fills in" the leftover space [proposed by Shea: Am J Phys Anthropol 47 (1977):289-300]. Against expectation, MSV is not significantly correlated with NCV or any cranial size variable. NCV, on the other hand, scales isometrically with facial size. The results of this pilot study suggest that NCV covaries with facial size, but that the MS does not simply fill in the leftover space in the face. The role, if any, of the MSs in midfacial function and architecture remains unclear. Larger sample sizes, additional environmental variables, and assessment of MS and NC shape are necessary to resolve this issue. 相似文献
116.
This paper tests six methods of predicting external nasal profile proportions, using the form and dimensions of the bony nasal (piriform) aperture. A sample of 122 lateral cephalograms was measured and traced before each method was attempted, under blind conditions where appropriate. Error was assessed by comparing predicted to actual proportions. Methods used by the following authors were tested: Krogman and Iscan (1986 The Human Skeleton in Forensic Medicine, Springfield: C.C. Thomas), Gerasimov (1955 The Reconstruction of the Face on the Skull), Prokopec and Ubelaker (2002 Forensic Sci. Commun. 4:1-4), Macho (1986 J. Forensic Sci. 31:1391-1403), George (1987 J. Forensic Sci. 32:1305-1330), and Stephan et al. (2003 Am J. Phys. Anthropol. 122:240-250). The two-tangent method by Gerasimov (1955 The Reconstruction of the Face on the Skull) was found to perform best at predicting a point on the nasal tip on male and female preoperative subjects. The method of Krogman and Iscan (1986 The Human Skeleton in Forensic Medicine, Springfield: C.C. Thomas) performed poorly, as did the nasal profile determination method (Prokopec and Ubelaker 2002 Forensic Sci. Commun. 4:1-4). The other methods, all derived by a process of regression calculations, were shown to perform with variable accuracy on this sample, despite the age range and ethnicity of this sample closely resembling that of the samples from which these methods were derived. 相似文献
117.
118.
目的:探讨免疫球蛋白辅助高流量鼻导管湿化氧疗(HHFNC)对重症肺炎患儿血气分析指标和免疫球蛋白水平的影响。方法:选取2017年6月到2018年9月期间在河北省儿童医院接受治疗的重症肺炎患儿93例,根据治疗方式的不同将93例重症肺炎患儿分为A组、B组和C组,A组给予经鼻持续气道正压通气(NCPAP),B组给予HHFNC,C组给予免疫球蛋白辅助HHFNC。比较三组患儿的临床疗效、血气分析指标、免疫球蛋白、临床症状改善情况、住院情况和并发症情况。结果:三组患儿的临床疗效整体比较差异无统计学意义(P0.05);通气后24 h,C组和B组患儿的二氧化碳分压(PaCO2)水平低于A组(P0.05);C组患儿的发绀消失时间、肺部哕音消失时间短于B组和A组(P0.05),治疗7 d后,C组患儿的免疫球蛋白G(Ig G)水平高于B组和A组(P0.05),C组和B组患儿的鼻损伤发生率均低于A组(P0.05)。结论:与NCPAP相比,HHFNC可更有效地改善重症肺炎患儿二氧化碳潴留的现象,且可降低鼻损伤的发生率,联用免疫球蛋白可有效改善患儿的体液免疫功能,促进患儿的康复。 相似文献
119.
目的:探讨中医序贯疗法联合丙酸氟替卡松鼻喷雾剂治疗慢性鼻窦炎的临床疗效。方法:选择2017年8月至2019年2月在我院接受治疗的120例慢性鼻窦炎Ⅱ型患者,采用抽签法分为观察组(n=61)和对照组(n=59)。两组均给予功能性内镜鼻窦手术治疗,对照组给予丙酸氟替卡松鼻喷雾剂治疗,观察组在对照组的基础上给予中医序贯疗法治疗。比较两组患者的临床疗效,治疗前后鼻黏膜纤毛传输速率(MTR)、血清白细胞介素4(IL-4)、白细胞介素6(IL-6)、肿瘤坏死因子(TNF-α)、中医症候积分水平的变化情况及并发症的发生情况。结果:治疗后,两组总有效率分别为96.72%,79.66%,观察组显著高于对照组(P0.05);两组MTR、血清IL-4、IL-8、TNF-α水平均较治疗前显著改善,且观察组MTR高于对照组,血清IL-4、IL-8、TNF-α水平明显低于对照组(P0.05);两组中医症候积分水平均较治疗前显著降低,且观察组中医症候积分水平显著低于对照组(P0.05)。治疗期间,两组并发症总发生率分别为1.64%、15.25%观察组显著低于对照组(P0.05)。结论:中医序贯疗法联合丙酸氟替卡松鼻喷雾剂慢性鼻窦炎患者的临床效果显著优于丙酸氟替卡松鼻喷雾剂治疗,其可更有效改善患者MTR。减轻炎症反应,且安全性更高。 相似文献
120.
目的:研究在单排CT轴位螺旋扫描联合多层面重组技术重建冠状面影像诊断鼻腔疾病,评价其诊断价值和可行性。方法:对2012年1月-2013年3月我院耳鼻咽喉科进行单排CT轴位螺旋扫描的患者,共219例,对这些患者加做冠状位扫描,比较重建后的影像资料与直接冠状位扫描的图像的分辨率情况,并评估重建质量及运用价值。,结果:单排CT轴位螺旋扫描后冠状面重组的图像:边界清楚、完整,数据无丢失。利用重组技术后重建的结构清晰、连续,能够真实地反映鼻腔、鼻窦及病变结构的实际情况。但分辨率较直接冠状位平扫的患者稍差。结论:单排CT轴位螺旋扫描后冠状面重组的图像,虽然分辨率不如直接冠状位扫描图像高,但与解剖结构、原图像等相结合仍能分辨出病变情况,基本可以满足诊断要求和临床需要。 相似文献