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71.
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   
72.
A 7-year-old Turkish boy had suffered from chronic coughing from early childhood. Severe bronchiectasis in the right lung was confirmed by bronchography. Ciliary beat frequency determined in a bronchial mucosal biopsy was markedly decreased (5.7 Hz). Electron microscopy revealed cilia with a length of 15 m. No structural abnormality was found. A possible link between the abnormally long, slow beating cilia and the clinical symptoms is discussed.  相似文献   
73.
Kumagai  Y.  Shimoji  K.  Honma  T.  Uchiyama  S.  Ishijima  B.  Hokari  T.  Fujioka  H.  Fukuda  S.  Ohama  E. 《Acta neurochirurgica》1992,115(3-4):71-78
Summary Several clinical problems related to the dorsal root entry zone lesions (DREZLs) in 15 patients with chronic pain are presented and discussed in terms of ratings of pain relief following surgery, development of sensory or motor weakness and postmortem histologies. Subjective pain relief exceeding 70% was achieved at around 2 weeks after the operations in most patients (13/15), and then decreased in some to 30 from 70% in the follow-up observations. Our new objective pain relief score was tested in these patients. A significant positive correlation between subjective pain relief and our objective pain relief scale was found, but some discrepancies between them were also found during the follow-up. Sensory loss, motor weakness, paraesthesia and a new pain were found as complications in 12, 7, 4 and 6 patients, respectively. Postmortem histological findings of the spinal cord in two patients with systemic lupus erythematosus and uterine cancer, who received bilateral DREZLs twice and bilateral DREZLs plus commissural myelotomy, respectively, indicate that care should be taken to avoid extension of the coagulation beyond the dorsal horn.  相似文献   
74.
文中主要讨论了“D”型牵伸的结构特点,同时分析了“牵伸区不集束、集束区不牵伸”的优越性。其次,对牵伸罗拉的表面结构和扭矩及其与提高粗纱牵伸质量之间的关系作了阐述。最后说明采用小模数牵伸齿轮的优点。  相似文献   
75.
In addition to the activation of cAMP-dependent pathways, odorant binding to its receptor can lead to inositol 1,4,5-trisphosphate (InsP3) production that may induce the opening of plasma membrane channels. We therefore investigated the presence and nature of such channels in carp olfactory cilia. Functional analysis was performed by reconstitution of the olfactory cilia in planar lipid bilayers (tip-dip method). In the presence of InsP3 (10 microM) and Ca2+ (100 nM), a current of 1.6 +/- 0.1 pA (mean +/- SEM, n = 4) was measured, using Ba2+ as charge carrier. The I/V curve displayed a slope conductance of 45 +/- 5 pS and a reversal potential of -29 mV indicating a higher selectivity for divalent cations. This current was characterized by two mean open times (3.0 +/- 0.4 ms and 42.0 +/- 2.6 ms, n = 4) and was strongly inhibited by ruthenium red (30 microM) or heparin (10 microg/mL). Importantly, the channel activity was closely dependent on the Ca2+ concentration, with the highest open probability (Po) at 100 nM Ca2+ (Po = 0.50 +/- 0.02, n = 4). Po is lower at both higher and lower Ca2+ concentrations. A structural identification of the channel was attempted by using a large panel of antibodies, raised against several InsP3 receptor (InsP3R)/Ca2+ release channel isoforms. The type 1 InsP3R was detected in carp cerebellum and whole brain, while a lower molecular mass InsP3R, which may correspond to type 2 or 3, was detected in heart, whole brain and the soma of the olfactory neurons. None of the antibodies, however, cross-reacted with olfactory cilia. Taken together, these results indicate that in carp olfactory cilia an InsP3-dependent channel is present, distinct from the classical InsP3Rs localized on intracellular membranes.  相似文献   
76.
 目的采用3种环糊精为毛细管电泳手性选择剂,研究美索巴莫对映体的拆分方法。方法用区带毛细管电泳模式,探讨β-环糊精、二甲基-β-环糊精和羧甲基-β-环糊精对美索巴莫对映体的拆分之影响,确定拆分美索巴莫对映体的最佳条件。此外,还探讨了手性识别机制。结果以β-环糊精和二甲基-β-环糊精作为手性选择剂时,不能使美索巴莫对映体达到基线分离,而羧甲基-β-环糊精能获得很好的分离结果。结论在拆分碱性药物对映体时,可在低pH下以酸性衍生化环糊精作为手性选择剂。  相似文献   
77.
实行特殊政策和实施特殊管理体制是世界经济特区共有的基本特征。正是这两个基本特征构成了特区经济学的两个理论前提。对经济特区实行特殊政策和实施特殊管理体制进行理论分析 ,目的在于为构筑特区经济学的理论体系作理论上的准备  相似文献   
78.
短毛细管区带电泳快速测定增效联磺片中三组分含量   总被引:2,自引:0,他引:2  
目的:在短毛细管上应用毛细管区带电泳法快速测定增效联磺片中磺胺甲嗯唑(SMZ)、磺胺嘧啶(SD)及甲氧苄氨嘧啶(TMP)三组分的含量。方法:采用未涂层弹性石英毛细管(35cm×50 μm,有效长度20 cm),以咖啡因为内标(IS),检测波长214 nm(0.01 AUFS),电压10 kV,重力进样(10 cm×5 s),温度15℃,运行缓冲液为20 mmol·L-1硼砂溶液(磷酸调pH6.0)。每次电泳运行前用0.1 mol·L-1氢氧化钠溶液、水及缓冲溶液各冲洗毛细管3 min。结果:SMZ、SD、TMP的线性范围分别为0.0398-0.199,0.0399-0.200,0.0160-0.0800 mg·mL-1。平均回收率(n=9)分别为99.4%,99.0%,99.8%;RSD均小于1.5%。结论:该法简便快捷,准确可靠,灵敏度高。  相似文献   
79.
Objectives: Evaluate the age-dependency of ciliary beat frequency (CBF) in biopsies after ciliogenesis in culture. Study Design: Retrospective analysis of CBF and ciliary ultrastructure in biopsies and after ciliogenesis from 203 individuals, aged 3 months to 74 years. Methods: All patients with successful culture were included. Ciliogenesis was obtained using the sequential monolayer-suspension culture technique for dissociated nasal epithelial cells. CBF was measured using computerized microscope photometry. Secondary ultrastructural abnormalities were evaluated in transmission electron microscopy. Results: There was no correlation between age and CBF, in either the biopsies (7.0 ± 2.6 Hz; n = 113) or after ciliogenesis in culture (8.1 ± 1.3 Hz; n = 203). Even in individuals older than 70 years, CBF was normal in bioptic material (6.7 ± 1.7 Hz) and after ciliogenesis in culture (7.9 ± 1.0 Hz). Also, in individuals less than 1 year of age CBF was normal in biopsies as well as after ciliogenesis. CBF correlated inversely with the percentage of secondary ultrastructural abnormalities in the biopsies as seen with transmission electron microscopy: 8.1 ± 1.8 Hz when ciliary ultrastructure was normal and 3.5 ± 3.3 Hz in cases of severe secondary ciliary dyskinesia. After ciliogenesis in culture, ciliary ultra-structure was always normal, as was CBF. Conclusion: CBF is age independent but correlates with secondary ultrastructural abnormalities. CBF after ciliogenesis in culture is the intrinsic one.  相似文献   
80.
PURPOSE: By the use of three different head models in EEG dipole analysis, we tried to model the origin of interictal and ictal epileptic activity as precisely as possible. Further, as a control, a second evaluation was made by an independent group to control for interindividual reliability of the dipole source analysis. With the realistic head model (CURRY) considering cortex, skull, and skin segmentation, the spike source was located. METHODS: In five patients with mesial temporal epileptogenesis, confirmed by successful epilepsy surgery, the spike source was close to the hippocampus, with a mean distance of the dipole source from the hippocampus of 13.6 mm (range, 9-17.2 mm). In one case the ictal EEG also could be analyzed and resulted in a dipole-source localization comparable to the interictal source. RESULTS: In both head models using either pure cortex segmentation only or a concentric three-shell model, the dipole source was systematically dislocated in a more superior position. Data analysis by a second group with independently chosen EEG samples and identical individual head model resulted in deviations of <5.3 mm. Data analysis using independently selected spikes and independently segmented head models resulted in deviations < or =16.7 mm. CONCLUSIONS: In four cases of extratemporal epileptogenesis, the origin of interictal epileptiform discharges was localized to the suspected primary epileptogenic zone.  相似文献   
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