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羟甲芬太尼(I)是一个新的高强度高选择性阿片μ受体激动剂。本文用cis-A-N-[1-(2-羟基-2-苯乙基)-3-甲基-4-哌啶基]-苯胺(II)或cis-N-[1-(苯甲酰甲基)-3-甲基-4-哌啶基]-苯胺(III)作为前体合成了[11C]-羟甲芬太尼,以便用正电子发射断层扫描(PET)来观察μ受体。通过水解cis-A-羟甲芬太尼(I)和cis-N-[1-(苯甲酰甲基)-3-甲基-4-哌啶]-N-苯基丙酰胺(cis-IV)的4-N-丙酰基分别获得II和III。溴乙烷的格氏试剂与回旋加速器产生的[11C]-二氧化碳反应后继而直接加入邻苯二甲酸二酰氯和2,6-二叔丁基吡啶生成同位素标记中间体[11C]-丙酰氯。[11C]-丙酰氯与OH-前体(II)反应后再经HPLC分离纯化直接得[11C]-羟甲芬太尼;[11C]-丙酰氯与酮-前体(III)反应后,再用硼氢化钠甲醇溶液处理,然后进行HPLC分离纯化得[11C]-羟甲芬太尼。两种方法均可获得ll.1~14.8GBq/μmol的特异性放射化学纯[11C]-羟甲芬太尼。总共耗时为40~50min(EOB)。 相似文献
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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
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Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献
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Tarsometatarsal joint: anatomic details on MR images 总被引:3,自引:0,他引:3
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IS Park H Kiyomoto F Alvarez YC Xu HE Abboud SL Abboud 《American journal of kidney diseases》1998,32(6):1000-1010
The renal insulin-like growth factor-I (IGF-I) system has been implicated in the pathogenesis of renal hypertrophy, altered hemodynamics, and extracellular matrix expansion associated with early diabetes. The relative abundance of IGF binding proteins (IGFBPs) in the renal microenvironment may modulate IGF-I actions. However, the precise IGFBPs expressed in the glomerular and tubulointerstitial compartments during diabetic renal growth have not been characterized. In the present study, in situ hybridization studies were performed to examine the expression of IGFBP-1 to -6 messenger RNAs (mRNAs) 3, 7, and 14 days after streptozotocin (STZ) injection in rats. In control, nondiabetic kidneys, all six IGFBP mRNAs were differentially expressed with a predominance of IGFBP-5. The onset of renal hypertrophy in STZ-induced diabetes was associated with a rapid and site-specific induction of IGFBP-1, -3, and -5 mRNAs. In contrast, basal expression of IGFBP-2, -4, and -6 mRNAs was not altered in diabetic rats. IGFBP-5 mRNA expression increased in diabetic glomeruli, cortical, and inner medullary peritubular interstitial cells at days 3, 7, and 14. Although normal glomeruli failed to express IGFBP-3, it was induced concomitantly with IGFBP-5 in diabetic glomeruli and cortical peritubular interstitial cells. IGFBP-1 mRNA levels also increased in cortical tubular cells at each time point tested. Peak induction of IGFBP-3 and -5 was observed at day 3, whereas IGFBP-1 was delayed until day 7. IGFBP-1, -3, and -5 mRNA levels declined by day 14, but remained persistently elevated above control. By immunoperoxidase staining, similar alterations in the pattern of IGFBP-3 and -5 protein expression were observed at each time point. The preferential and site-specific increase in IGFBP-1, -3, and -5 suggest that these IGFBPs may regulate the local autocrine and/or paracrine actions of IGF-I and contribute to the pathogenesis of the early manifestations of diabetic nephropathy. 相似文献
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Chen M Aosai F Norose K Mun HS Ishikura H Hirose S Piao LX Fang H Yano A 《International immunology》2004,16(7):937-946
Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by the presence of autoantibodies and lupus nephritis. In the present study using New Zealand Black (NZB) x New Zealand White (NZW) F1 (NZBW F1) mice, we planned to investigate the effects of Toxoplasma gondii infection on the progress of lupus nephritis. Female NZBW F1 mice at the age of 2 months were perorally infected with T. gondii. The T. gondii infection reduced the number of mice developing proteinuria and immune complex deposits in their kidneys and prolonged their life span. A marked decrease in the levels of IgM and IgG anti-DNA antibodies, especially IgG2a and IgG3 subclasses, was observed in T. gondii-infected NZBW F1 mice at 9 months of age. The level of anti-HSP70 IgG autoantibody in the sera of NZBW F1 mice was significantly higher than that in control mice at 9 weeks after T. gondii infection. Moreover, NZBW F1 mice treated with anti-self heat shock protein 70 (HSP70) monoclonal antibody were substantially protected against the onset of glomerulonephritis. Further, down-regulation of intracellular expression of IFN-gamma and IL-10 was shown in spleen cells of T. gondii-infected NZBW F1 mice. This was consistent with the previous data indicating the involvement of Th1-type and Th2-type cytokines in the development of lupus-like nephritis. These results suggest that T. gondii infection is capable of preventing the development of autoimmune renal disorder in NZBW F1 mice. 相似文献
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E. Hamsˇíková M. Sˇmahel M. Sapp N. Munˇoz F. X. Bosch K. V. Shah V. Vonka 《Archives of virology》1997,142(2):413-416
Summary. The L1 capsid proteins derived from human papillomavirus (HPV) type 33 were expressed in a recombinant baculovirus system
using Sf9 insect cells. Selected sera originating in women from case-control study carried out in Spain and Colombia found
negative and positive for HPV16, 18, 31, 33 and 35 DNA were tested in ELISA for the presence of IgG antibodies to purified
virus-like particles (VLP). The reactivity was type-restricted with the possible exception of HPV31.
Received July 4, 1996 Accepted September 17, 1996 相似文献