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31.
Effects of sodium salts of various monovalent inorganic anions on transdermal permeation of salicylic acid were investigated. In in-vitro experiment using a Franz-type diffusion cell and excised mouse skin, the permeation-enhancing activities of the sodium salts of inorganic anions were roughly proportional to lyotropic Hofmeister swelling abilities of the anions; F?<SO4 2?<Cl? <ClO4 ?<NO3 <SCN? <Br <I?, i.e. l, Br and SCN increased the flux of drugs through the mouse skin, while F?, SO4 2?, Cl?, ClO4 ? and NO3 ? decreased or did not affect the flux. In invivo experiment using the rabbit as the test animal, the plasma concentration of salicylic acid of the rabbit to which 10%-salicylic acid ointment containing 5%-Nal or NaBr was applied was significantly higher than that of the rabbit to which the ointment without the electrolytes was applied. The amounts of sterol leached out of stratum corneum sheet when the sheet was immersed in aqueous solutions of Nal, NaBr, or NaSCN were much more than that of stratum corneum immersed in aqueous solutions of the other inorganic anions. The FTIR/ATR spectroscopy showed that the peaks at 2853 cm?1 and 2924 cm?1 in the IR absorption spectrum of the stratum corneum sheet of the mouse were shifted to higher frequencies by the anions which enhanced the transdermal drug permeation, while not shifted by the anions which did not have any permeation-enhancing activities or have permeation-reducing activities. These results suggest that sodium salts of some anions such as iodide, bromide and thiocyanate enhance transdermal permeation of salicylic acid through swelling and perturbation of the skin structure by these anions. 相似文献
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33.
Background Previous studies have noted that there is a high utilization rate of traditional Chinese medicine (TCM) services in Taiwan, China and in western countries, but few studies investigated factors associated with the utilization of TCM in Taiwan. This study analyzes the utilization rate and the factors associated with the utilization of TGM in Taiwan. Methods Data for this study were from the 2002 HPKAP Survey that conducted the face-to-face questionnaire interviews of people aged 15 years and over from October 2002 to March 2003 in Taiwan. This study analyzed the utilization of TCM outpatient services, including admission to the hospital and clinic visits. Results A total of 26 755 participants completed the survey in the six-month period. The data revealed that 10.4% of participants had utilized TCM services in the past one month while 4.2% of participants utilized TCM only (without using Western medicine outpatient services (WM) or Folk therapy (F'I')). The average visits of TCM services per patient was higher among people who had utilized TCM and FT services (2.68 visits) than among those who had utilized WM and FT services (2.15 visits) or TCM services alone (2.15 visits) during the previous one month. Younger people (odds ratio OR= 1.78, 95%C/= 1.47-2.16), women (compared with men), and people with higher education levels (OR = 1.58, 95%CI =1.25-1.98) were more likely to visit TCM than compared groups. People with self-reported poor health status (OR = 2.07,95%CI = 1.76-2.44) and people who exercise regularly (OR = 1.17, 95%CI = 1.07-1.27) had higher ORs to visit TCM service than comparison group.Conclusions There is a high utilization of TCM in Taiwan. Further studies are needed to investigate the related factors and determinants between the utilization of TCM and the utilization of FT in Taiwan. 相似文献
34.
Performance measurement of the microPET focus 120 scanner. 总被引:6,自引:0,他引:6
Jin Su Kim Jae Sung Lee Ki Chun Im Su Jin Kim Seog-Young Kim Dong Soo Lee Dae Hyuk Moon 《Journal of nuclear medicine》2007,48(9):1527-1535
The microPET Focus 120 scanner is a third-generation animal PET scanner dedicated to rodent imaging. Here, we report the results of scanner performance testing. METHODS: A (68)Ge point source was used to measure energy resolution, which was determined for each crystal and averaged. Spatial resolution was measured using a (22)Na point source with a nominal size of 0.25 mm at the system center and various off-center positions. Absolute sensitivity without attenuation was determined by extrapolating the data measured using an (18)F line source and multiple layers of absorbers. Scatter fraction and counting rate performance were measured using 2 different cylindric phantoms simulating rat and mouse bodies. Sensitivity, scatter fraction, and noise equivalent counting rate (NECR) experiments were repeated under 4 different conditions (energy window, 250 approximately 750 keV or 350 approximately 650 keV; coincidence window, 6 or 10 ns). A performance phantom with hot-rod inserts of various sizes was scanned, and several animal studies were also performed. RESULTS: Energy resolution at a 511-keV photopeak was 18.3% on average. Radial, tangential, and axial resolution of images reconstructed with the Fourier rebinning (FORE) and filtered backprojection (FBP) algorithms were 1.18 (radial), 1.13 (tangential), and 1.45 mm full width at half maximum (FWHM) (axial) at center and 2.35 (radial), 1.66 (tangential), and 2.00 mm FWHM (axial) at a radial offset of 2 cm. Absolute sensitivities at transaxial and axial centers were 7.0% (250 approximately 750 keV, 10 ns), 6.7% (250 approximately 750 keV, 6 ns), 4.0% (350 approximately 650 keV, 10 ns), and 3.8% (350 approximately 650 keV, 6 ns). Scatter fractions were 15.9% (mouse phantom) and 35.0% (rat phantom) for 250 approximately 750 keV and 6 ns. Peak NECR was 869 kcps at 3,242 kBq/mL (mouse phantom) and 228 kcps at 290 kBq/mL (rat phantom) at 250 approximately 750 keV and 6 ns. Hot-rod inserts of 1.6-mm diameter were clearly identified, and animal studies illustrated the feasibility of this system for studies of whole rodents and mid-sized animal brains. CONCLUSION: The results of this independent field test showed the improved physical characteristics of the F120 scanner over the previous microPET series systems. This system will be useful for imaging studies on small rodents and brains of larger animals. 相似文献
35.
YOU Han XIAO Bing CUI Da-Xiang SHI Yong-Quan FAN Dai-Ming 《World journal of gastroenterology : WJG》1998,4(4)
AIM To clone novel gastric cancer-associated genes and investigate their roles in gastric cancer occurrence.METHODS A method called differential display was used which allows the identification of differentially expressed genes by using PAGE to display PCR-amplified cDNA fragments between gastric cancer cells and normal gastric mucosa cells. These fragments were cloned into plasmid vector pUC18. Homology analysis was made after sequencing these fragments.RESULTS Two novel genes were identified compared with sequences from GenBank. One was registered with the AD number AF 051783. In situ hybridization showed that these two novel genes expressed specifically in gastric cancer tissues.CONCLUSION The two novel genes obtained by differential display were confirmed to be gastric cancer-associated genes using in situ hybridization. 相似文献
36.
中风后癫痫的临床研究 总被引:5,自引:0,他引:5
本文报告36例中风后癫痫发作的临床和CT资料。通过回顾性病历复习和随访发现,中风后癫痫的发生率占同期住院中风患者的5.26%,以蛛网膜下腔出血和脑栓塞发生癫痫比率最高,分别为15%和12.5%。癫痫发作与CT所见病灶分布密切相关,皮质病灶较皮质下病灶更易发生病病。癫痫发作可发生于中风后任何时期,但早期癫痫以出血性中风多见,而迟发性癫痫则更多见于脑梗塞患者。 相似文献
37.
Expression and distribution of vascular endothelial growth factor protein in human brain tumors 总被引:9,自引:0,他引:9
T. Pietsch Markus M. Valter Helmut K. Wolf A. von Deimling H.-J. Su Huang Webster K. Cavenee Otmar D. Wiestler 《Acta neuropathologica》1997,93(2):109-117
Marked neovascularization is a hallmark of many neoplasms in the nervous system. Recent reports indicate that the endothelial
mitogen vascular endothelial growth factor (VEGF) may play a critical role in the regulation of vascular endothelial proliferation
in malignant gliomas. Using novel monoclonal antibodies to the VEGF polypeptide we have determined the expression and cellular
distribution of VEGF protein in a representative series of 171 human central nervous system (CNS) tumors by immunohistochemistry
and immunoblotting. In agreement with previous in situ hybridization data, 19 out of 20 glioblastomas (95%) showed immunoreactivity
for VEGF, whereas both the percentage of immunoreactive tumors and the extent of immunoreactivity for VEGF were significantly
lower in astrocytomas. Of the pilocytic astrocytomas (WHO grade I) 44% were immunoreactive for VEGF, but we observed several
cases with pronounced vascular proliferates in the absence of VEGF. In ependymomas, meningiomas, hemangioblastomas, and primitive
neuroectodermal tumors, there was no correlation between VEGF expression, vascular endothelial proliferation and the grade
of malignancy. Oligodendrogliomas and the oligodendroglial component of mixed gliomas lacked immunoreactive VEGF, indicating
that endothelial growth factors other than VEGF may regulate tumor angiogenesis in these neoplasms. Western blot analysis
showed a predominant VEGF protein species of 23 kDa and confirmed the immunohistochemical data in all cases. Our findings
demonstrate that VEGF is expressed in a wide spectrum of brain tumors in which it may induce neovascularization. However,
other angiogenic factors also appear to contribute to the vascularization of CNS neoplasms.
Received: 18 April 1996 / Revised, accepted: 20 August 1996 相似文献
38.
39.
聚合酶链反应(PCR)对单纯疱疹病毒性脑炎的临床诊断价值 总被引:2,自引:1,他引:1
应用聚合酶链反应(PCR)检测技术对118例颅内感染性疾病患者及37例无神神经系统疾病患者脑脊液(CSF)中的单纯疱疹病毒DNA(HSV-DNA)进行了检测及分型。结果提示:“散发性脑炎”组的阳性率为38.46%(20/52),细菌、真菌性脑膜炎、其它病毒性脑炎组以及无神经系统疾病组均为阴性。作者认为:①本检测是目前单纯疹病毒性脑炎(HSE)较为简便而准确的早期诊断方法之一;②HSV分型检测,对病原诊断更具有全面性;③两型单纯疱疹病毒均可引起HSE。 相似文献
40.
M D Mesa M Anguita A López-Granados R Vivancos J Suárez de Lezo F Vallés G Bueno 《Revista espa?ola de cardiología》1991,44(5):347-350
Two cases of digitalis toxicity due to uncontrolled ingestion of medicinal herbs are presented. The first of them was caused by oleander (Nerium oleander); digoxinemia levels were very high in this patient (4.44 ng/l), who presented many brady- and tachyarrhythmias. These arrhythmias disappeared when digoxinemia returned to normal values. The second patient had atrial fibrillation with slow ventricular rate, severe hypokalemia (2.1 mEq/l) and normal digoxinemia levels. He was taking medicinal herbs for a cold, with sorbitol between its components. Sorbitol may be similar to mannitol and glycerol (osmotic diuretic drugs) when taken at high doses. Uncontrolled ingestion of medicinal herbs is not safe, and severe poisoning can occur. 相似文献