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1.
A. Tavakkolizadeh A.P. Ramsanahie L.L. Levitsky M.J. Zinner S.W. Ashley E.E. Whang D.B. Rhoads 《The Journal of surgical research》2004,121(2):273
The objective of this study was to examine the function of vagal innervation in maintaining diurnal rhythmicity in the expression of intestinal absorptive genes. Rats underwent truncal vagotomy and were maintained for 7 days on nighttime scheduled feeding (12-h light/12-h dark cycle). Vagotomized rats (V; n = 9) were pair-fed with sham-operated controls (S; n = 4). Unoperated normal rats (N; n = 6) were also included as controls. Half the rats were killed 3 h after lights on (ZT3; Zeitgeber Time, with lights-on considered ZT0) and the other half at ZT9, the time interval over which we have previously shown that sucrase and sugar transporter expression exhibits a significant anticipatory increase. RNA and protein extracted from mucosa of proximal jejunums were subjected to Northern and Western blot analyses to assess the increase in gene expression. Sham operation did not alter the normal diurnal rhythmicity of intestinal gene expression. Control rats (S plus N) exhibited the expected increase in RNA levels at ZT9 versus ZT3 for SGLT1 (4.5-fold), GLUT2 (5.3-fold), GLUT5 (4.1-fold), and sucrase (2.9-fold; P > 0.001 in all cases). In contrast, the induction in V rats was markedly blunted for GLUT2 (1.3-fold) and sucrase (1.5-fold) but not for SGLT1 (5.0-fold) or GLUT5 (4.2-fold). The mRNA levels for GLUT2 and sucrase at ZT9 were significantly lower in V rats versus controls (P < 0.001). GLUT2 and SGLT1 protein levels exhibited a parallel pattern: SGLT1 induction was 4.3-fold in control rats (P < 0.01) and 3.8-fold in V rats (P <0.01), whereas GLUT2 induction was 3.3-fold in control rats (P < 0.01) but only 1.4-fold in V rats (NS). Our results indicate that signaling through the vagus nerve is necessary to maintain the anticipatory induction pattern of GLUT2 and sucrase. The persistent rhythm in both SGLT1 and GLUT5 indicates that (1) diurnal induction of these genes is independent of vagal innervation and (2) the procedure did not cause an overall loss of intestinal function. Thus, entrainment of anticipatory diurnal gene expression in the intestine occurs via two separate pathways that are differentially dependent on vagal input. 相似文献
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3.
Chang Hyun Lee Jung-Gi Im Jin Mo Goo Hyun Ju Lee Sung-Tae Hong Cheng Hua Shen Doo Hyun Chung Kyu Ri Son Jung Min Chang Hong Eo 《Korean journal of radiology》2007,8(5):372-381
OBJECTIVE: To investigate the serial CT findings of Paragonimus westermani infected dogs and the microscopic structures of the worm cysts using Micro-CT. MATERIALS AND METHODS: This study was approved by the committee on animal research at our institution. Fifteen dogs infected with P. westermani underwent serial contrast-enhanced CT scans at pre-infection, after 10 days of infection, and monthly thereafter until six months for determining the radiologic-pathologic correlation. Three dogs (one dog each time) were sacrificed at 1, 3 and 6 months, respectively. After fixation of the lungs, both multi-detector CT and Micro-CT were performed for examining the worm cysts. RESULTS: The initial findings were pleural effusion and/or subpleural ground-glass opacities or linear opacities at day 10. At day 30, subpleural and peribronchial nodules appeared with hydropneumothorax and abdominal or chest wall air bubbles. Cavitary change and bronchial dilatation began to be seen on CT scan at day 30 and this was mostly seen together with mediastinal lymphadenopathy at day 60. Thereafter, subpleural ground-glass opacities and nodules with or without cavitary changes were persistently observed until day 180. After cavitary change of the nodules, the migratory features of the subpleural or peribronchial nodules were seen on all the serial CT scans. Micro-CT showed that the cyst wall contained dilated interconnected tubular structures, which had communications with the cavity and the adjacent distal bronchus. CONCLUSION: The CT findings of paragonimiasis depend on the migratory stage of the worms. The worm cyst can have numerous interconnected tubular channels within its own wall and these channels have connections with the cavity and the adjacent distal bronchus. 相似文献
4.
艺术嗓音歌声客观评价初探 总被引:1,自引:0,他引:1
目的探讨客观评价艺术嗓音歌声的方法。方法对48名声乐专业青年大学生录制专业训练歌声信号,提取歌声平均能量、频率误差、音域误差作为评价参数,使用神经网络方法和多元线性回归方法客观评价歌声质量,并与资深专业教师的主观评价进行比较。结果客观评价歌声质量的方法中,神经网络方法误差在4%之内,而线性回归方法误差在6%之内,前者较优。结论神经网络方法利用评价参数能正确客观评价歌声质量,有助于科学地指导选拔和训练艺术嗓音人才。 相似文献
5.
Mun Su Kang Dong Il Park Jung Ho Park Hong Joo Kim Yong Kyun Cho Chong Il Sohn Woo Kyu Jeon Byung Ik Kim 《Taehan Sohwagi Hakhoe chi》2006,48(6):395-400
BACKGROUND/AIMS: Bamboo joint-like (BJL) appearance is an endoscopic finding characterized by swollen longitudinal folds transversed by erosive fissures or linear furrows on the lesser curvature side of gastric body and cardia. It has been reported to be associated with Crohn's disease (CD). This study was aimed to evaluate the incidence of BJL appearance in Korean patients with CD. METHODS: From January to December in 2005, we performed esophagogastroduodenoscopy (EGD) in patients diagnosed as CD and ulcerative colitis (UC) in our hospital. Non-inflammatory bowel disease (IBD) subjects with upper gastrointestinal symptoms who underwent EGD were consecutively enrolled during the same period. One endoscopist performed all the endoscopic examinations to avoid inter-observer variation. A dye-spraying technique with 0.4% indigocarmine was used to allow the detection of subtle changes during the endoscopic examination. RESULTS: A total of 21 patients with CD (mean age+/-SD, 40+/-15 yr; M/F, 13/8), 28 patients with UC (42+/-15 yr; 21/7), and 685 non-IBD subjects (49+/-14 yr; 354/331) were enrolled. EGD findings in CD patients were gastric erosions (11/21), chronic superficial gastritis (5/21), chronic atrophic gastritis (1/21), duodenal erosions or ulcers (2/21), and normal (2/21). Incidence of BJL appearance was significantly higher in patients with CD (47.6%, 10/21) than others (UC, 3.6%, 1/28; non-IBD, 0.1%, 1/685) (p< 0.0001). Among patients with CD, incidence of BJL appearance was not significantly different according to the sex, status of H. pylori infection, Vienna classification for phenotype, medications or EGD findings. CONCLUSIONS: BJL appearance on the gastric body and cardia can be a diagnostic clue to CD. 相似文献
6.
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
7.
Li‐Hsuan Wang Kuang‐Yang Hsu Yow‐Shieng Uang Feng‐Lin Hsu Li‐Ming Yang Shwu‐Jiuan Lin 《Phytotherapy research : PTR》2010,24(6):852-858
The impacts of caffeic acid (3,4‐dihydroxycinnamic acid, CA) on the pharmacokinetics of levodopa (L‐dopa) were studied in rabbits. A single dose of 5/1.25 mg·kg?1 l ‐dopa/carbidopa was administered alone or was co‐administered with three different doses of caffeic acid (2.5, 5, and 10 mg·kg?1), or a single dose of 5 mg·kg?1 caffeic acid was administered alone via an intramuscular route to six rabbits each in a crossover treatment protocol. Plasma levels of l ‐dopa, 3‐O‐methyldopa (3‐OMD), caffeic acid, and ferulic acid were determined and subsequently used to calculate their pharmacokinetic parameters. The results indicated that caffeic acid administered at a dose of 10 mg·kg?1 decreased about 22% of the peripheral formation of 3‐OMD and about 31% of the Cmax of 3‐OMD. In addition, the metabolic ratios (MR, AUC of 3‐OMD/AUC of L‐dopa) decreased by about 22%. Results also indicated that caffeic acid significantly decreased the proportion of 3‐OMD (p < 0.05). In contrast, the parameters of neither caffeic acid nor ferulic acid were significantly affected by l ‐dopa/carbidopa. In conclusion, caffeic acid at a dose of 10 mg·kg?1 can significantly affect the COMT metabolic pathway of L‐dopa. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
8.
Cisplatin is a common cause of hypomagnesemia and hypokalemia due to renal magnesium (Mg) and potassium (K) losses. Magnesium plays an important role in the maintenance of intracellular K. An unrecognized and untreated Mg depletion can lead to a refractory K repletion. We describe two patients with hypomagnesemia-associated refractory hypokalemia following cisplatin following cisplatin therapy. Potassium supplementation failed to replace the K deficit. Profound hypokalemia persisted until hypomagnesemia was recognized and corrected. In neither patient was the concurrent hypomagnesemia recognized until the 11th and 9th hospital days. These two cases demonstrated the association of a refractory K repletion and an Mg deficiency. Thus, both serum K ion and Mg levels should routinely be assessed in patients who require cisplatin therapy. 相似文献
9.
Simple measurement of spinal cord evoked potential: a valuable data source in the rat spinal cord injury model. 总被引:1,自引:0,他引:1
Jong-Pil Park Ki-Jeong Kim Ji Hoon Phi Chul-Kee Park Jong-Hoon Kim Hyo Jin Kang Dohun Lee Kyu Hyun Han Kyu-Chang Wang Sun Ha Paek 《Journal of clinical neuroscience》2007,14(11):1099-1105
Measurement of spinal cord evoked potentials (SCEPs) is proposed as a means of predicting locomotion outcome in the rat spinal cord injury (SCI) model. Using 55 rats, three reproducible peak waves (waves I, II and III) were observed during stimulation at the C7 level with recording at the L1 epidural space. Hemisection at the T13 level showed three wave loss patterns: wave III loss only, loss of both wave II and III, and loss of all three waves. Defining an ideal SCI model as establishment of stable monoparesis or paraparesis, all animals in the wave II-III loss group showed favorable results. Histological data and electrophysiological properties allowed reasonable assumptions of wave origin: wave I from extrapyramidal tracts, wave II from the ventral corticospinal tract, and wave III from the dorsal corticospinal tract. Complete destruction of pyramidal tracts in both dorsal and ventral fibers was essential for long-term impairment of locomotion. 相似文献
10.
Oh SH Kim JK Song KS Noh SM Ghil SH Yuk SH Lee JH 《Journal of biomedical materials research. Part A》2005,72(3):306-316
Sol-gel transition temperature-controllable Pluronic F127/F68 mixtures including mildly crosslinked alginate and nonsteroidal anti-inflammatory drug (ibuprofen) were prepared to evaluate their potential as tissue adhesion barrier gels. The sol-gel transition temperatures of the Pluronic mixtures could be controlled by adjusting F127/F68 ratio and polymer concentration. The mildly crosslinked alginate with still flow property provided the residence stability of Pluronic mixture gels in the body. Ibuprofen was loaded in Pluronic mixtures to reduce inflammatory response in the body and, thus, to prevent tissue adhesion. The gelation temperatures of the Pluronic mixtures were not affected by the alginate but lowered by the addition of ibuprofen. The in vitro drug release behavior and in vivo peritoneal tissue adhesion of the Pluronic mixtures with the sol-gel transition just below body temperatures were investigated. The drug release behavior from the ibuprofen (1 wt%)-loaded Pluronic mixture gels at 37 degrees C was examined using a membrane-less dissolution model. The drug in the mixture gels was released continuously up to about 45-65% of the total loading amount during the first 7 days. For in vivo evaluation of tissue anti-adhesion potential, the Pluronic mixtures with/without drug were coated on the peritoneal wall defects of rats and their tissue adhesion extents and tissue reactions (inflammatory response, granulation tissue formation, and toxicity in organs) were compared. It was observed that ibuprofen has a positive effect for the peritoneal tissue anti-adhesion. The Pluronic F127/F68/alginate/ibuprofen mixture gel (25 wt% of F127/F68 [7/3], 1 wt% ibuprofen) was highly effective for the prevention of peritoneal tissue adhesion and showed a relatively low inflammatory response and non-toxicity, and thus can be a good candidate material as a coatable or injectable tissue adhesion barrier gel. 相似文献