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101.
S. Kawa M. Tokoo O. Hasebe K. Hayashi H. Imai H. Oguchi K. Kiyosawa S. Furuta T. Homma 《British journal of cancer》1994,70(3):481-486
A comparative study of a new tumour marker, CA242, and CA19-9 was conducted with special reference to their diagnostic usefulness in pancreatic cancer. CA242 showed sensitivity similar to that of CA19-9 for overall cases and early cases (stage I tumour) of pancreatic cancer. For other malignancies, the positive rates of CA242 were lower than those of CA19-9 except for colorectal cancer. An important characteristics of CA242 was that it was only slightly and infrequently elevated in the sera of patients with benign diseases such as chronic pancreatitis, chronic hepatitis and liver cirrhosis. This characteristic was more apparent in the patients with benign obstructive jaundice, indicating that the serum level of this marker was scarcely affected by cholestasis. Using cut-off levels corresponding to a 90% specificity, the clinical results obtained with CA242 in the diagnosis of pancreatic cancer were similar to those obtained with CA19-9, except that CA19-9 was falsely negative in some patients with early-stage pancreatic cancer. These findings suggest the usefulness of this marker for screening pancreatic cancer in patients on their first hospital visit. However, CA242 was found to be influenced by the Lewis blood group system. This unfavourable result is attributed to the C241 catcher antibody of this assay system, which has almost the same epitope specificity as the C50 and the NS19-9 monoclonal antibodies. In conclusion, CA242 is superior to CA19-9 in diagnosing pancreatic cancer by virtue of its higher specificity. 相似文献
102.
103.
Sakamoto S Inagawa T Ikawa F Kawamoto H Ohbayashi N 《Neurologia medico-chirurgica》2002,42(6):250-254
A 65-year-old woman presented with multiple dissecting aneurysms of the anterior cerebral artery (ACA) manifesting as hemiparesis on the right with dominance in the lower extremity. Computed tomography revealed hematoma in the left frontal lobe, corresponding to the area perfused by the callosomarginal artery. Initial angiography showed string sign and occlusion in the distal portion of the left callosomarginal artery and abnormal feeding suggesting double lumen of the A2 portion of the left ACA. The patient was treated conservatively under a diagnosis of multiple spontaneous dissecting aneurysms of the left ACA. Repeat angiography on Day 8 showed improvement of the string sign and occlusion in the left callosomarginal artery, and change of the double lumen of the A2 portion into string sign. Further angiography on Day 36 showed normalization of the left callosomarginal artery and improvement of the string sign in the A2 portion. Multiple spontaneous dissecting aneurysms of the ACA are extremely rare. Serial angiography beginning in the early stage will be important for correct diagnosis. 相似文献
104.
Furukawa H Hamada T Hayashi MK Haga T Muto Y Hirota H Yokoyama S Nagasawa K Ishiguro M 《Molecular pharmacology》2002,62(4):778-787
Many biogenic amines evoke a variety of physiological responses by acting on G protein-coupled receptors. We have determined the conformation of two acetylcholine analogs, (S)-methacholine and (2S,4R,5S)-muscarine, bound to the M(2) muscarinic acetylcholine receptor (M(2) mAChR) by NMR spectroscopy. The analysis of the transferred nuclear Overhauser effect indicated that the receptor selectively recognized the conformers of (S)-methacholine and (2S,4R,5S)-muscarine with the gauche O-C2-C1-N dihedral angle at +60 degrees. This is distinct from the predominant conformations of these ligands in solution with O-C2-C1-N dihedral angle (+80 to approximately 85 degrees ) in the absence of the M(2) mAChR, as assessed by analyses of the coupling constants and nuclear Overhauser effect spectroscopy. We have also built a molecular model of the M(2) mAChR-(S)-methacholine complex, based on the X-ray crystallographic structure of rhodopsin. This model indicated that the conformation with the gauche O-C2-C1-N dihedral angle at +55.5 degrees, which is similar to the one determined by NMR measurement, is energetically favored in the binding of (S)-methacholine to the receptor. We suggest that this conformation represents the binding of the agonist to the M(2) mAChR in the absence of G protein. 相似文献
105.
It was demonstrated that trans-stilbene was metabolically activated to the estrogenic compound by rat liver microsomes (Sugihara et al., Toxicol. Appl. Pharmacol., 167, 46-54 (2000)). In this study, determination of the isoforms of cytochrome P450 involved in the oxidation of the proestrogen, trans-stilbene, to its hydroxylated metabolites was examined. When trans-stilbene was incubated with rat liver microsomes in the presence of NADPH, estrogenic compounds, trans4-hydroxystilbene and trans-4,4'-dihydroxystilbene were formed. Comparison of the oxidase activity among liver microsomes of untreated, 3-methylcholanthrene-treated, acetone-treated, clofibrate-treated, dexamethasone-treated and phenobarbital-treated rats toward trans-stilbene showed that those from 3-methylcholanthrene-treated rats exhibited the highest activity. Human liver microsomes also catalyzed the oxidation in varying degrees. Variation in trans-stilbene oxidase activity was closely correlated to that of phenacetin O-deethylase activity. The oxidase activity was inhibited by alpha-naphthoflavone; however, in this case trans-4,4'-dihydroxystilbene was not detected. The oxidase activity toward trans-stilbene was exhibited by recombinant human cytochrome P450 1A1 and 1A2 expressed in a human B lymphoblastoid cell line. 相似文献
106.
Matsuzaki S Hayashi I Nara Y Kamata K Yamanaka M Okamoto H Hoka S Majima M 《International immunopharmacology》2002,2(13-14):2005-2012
Involvements of kinin and prostaglandin and their interaction in noxious thermal stimuli were investigated in noninflamed and inflamed rats. The nociceptive response was evaluated from the escape latency of foot withdrawal to the thermal stimuli with a beam of light. The escape latency in kininogens-deficient Brown Norway (B/N-) Katholiek rats was significantly longer than that in the normal strain, B/N-Kitasato rats. The latency in B/N-Kitasato rat was prolonged by administration of a bradykinin (BK) B2 receptor antagonist, FR173657 (30 mg/kg, p.o.), whereas it was shortened by pretreatment with a kininase II inhibitor, captopril (10 mg/kg, i.p.). Both agents did not affect the latency in B/N-Katholiek rats. In normal Sprague-Dawley (SD) rat, administration of indomethacin did not change the escape latency against the thermal stimuli. In contrast, administration of indomethacin or a relatively cyclooxygenase-1-selective inhibitor, mofezolac (10 mg/kg, p.o.) significantly reduced numbers of writhing reaction in mice induced by acetic acid solution. Injection of lipopolysaccharide (1 mg/kg, i.v.) resulted in shortening escape latency at 8 h after the injection in B/N-Kitasato rats. This hyperalgesia could be reversed by pretreatment of the rats with indomethacin, a cyclooxygenase-2-selective inhibitor JTE-522 (10 mg/kg, p.o.), or FR173657, but not with mofezolac. The hyperalgesia was not seen in B/N-Katholiek rats. These results indicate that kinin has major participation in peripheral skin thermal nociception under noninflamed condition, although cyclooxygenases may have little participation. Prostaglandins produced by cyclooxygenase-2 could coordinate with BK to elicit hyperalgesia during inflammation induced by lipopolysaccharide. 相似文献
107.
Microcystic adnexal carcinoma (MAC) affects predominantly the face and seldom metastasizes. We report a case occurring in the axilla of a 63-year-old male. Histology revealed the characteristic features of MAC. Eleven months after the excision, he underwent a reexcision with wide margins because of local recurrence. Histologically, the central area of the recurrent lesion revealed the typical histologic features of MAC, and the periphery showed a proliferation of irregular duct-like and glandular structures with a mixed pattern. Two lymph nodes that were not adherent to the tumor had metastatic tumor cells. The present case confirms that MAC can metastasize, although it may also be hypothesized that the recurrent lesion represented transformation into a higher-grade carcinoma. 相似文献
108.
109.
Valved jugular vein segments for right ventricular outflow tract reconstruction in young sheep 总被引:9,自引:0,他引:9
Herijgers P Ozaki S Verbeken E Van Lommel A Meuris B Lesaffre E Daenen W Flameng W 《The Journal of thoracic and cardiovascular surgery》2002,124(4):798-805
OBJECTIVE: This study was undertaken to investigate the degeneration and calcification of valved bovine jugular vein segments for right ventricular outflow tract reconstruction in juvenile sheep. METHODS: Seven valved bovine jugular vein conduits (Contegra model 220; VenPro Corporation, Irvine, Calif) and 3 control conduits (MH100; Medtronic, Inc, Minneapolis, Minn) were implanted in the pulmonary artery in young sheep. After 20 weeks the conduits were explanted and qualitatively analyzed by epicardial echocardiography, gross examination, x-ray analysis, light microscopy, and transmission electron microscopy. Calcification was determined quantitatively by flame atomic absorption spectrometry. RESULTS: Two Contegra conduits could not be analyzed because of endocarditis. All other Contegra conduits functioned well, with preserved structure and minimal calcification. The control MH100 conduits exhibited extensive fibrous sheathing, with calcification of the aortic wall portion and the commissural part of the Hancock valve. CONCLUSIONS: The Contegra conduit's performance was clearly superior to that of the control MH100 conduit when implanted in the pulmonary artery position in juvenile sheep for 5 months. 相似文献
110.
Nakamura K Kokubo H Kato K Aoki S Taki T Mitsui K Yamada Y Honda N Fukatsu H Kamijo A 《Hinyokika kiyo. Acta urologica Japonica》2002,48(8):483-486
A 32-year-old woman complained of right back pain and pyuria. The plain radiograph (KUB) and drip infusion pyelography (DIP) demonstrated a right renal stone and hydronephrosis. The stone was successfully treated using extracorporeal shock wave lithotripsy. Infrared spectrophotometry revealed that the stone was composed of pure ammonium acid urate. The patient had a 3-year history of excessive anorexia. The low-caloric diet was considered to have caused the disease. 相似文献