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71.
During our systematic studies on the arginine vasopressin receptor V1a-antagonistic activity of 1-(1-benzoyl substituted 4-piperidyl)-3,4-dihydro-2(1H)-quinolinones, we found a general substituent effect on the benzene ring. Hydrogen-bonding ability at the ortho position was especially important for enhancement of the affinity of multi-substituted analogs. Details of the syntheses and structure-activity relationships for this series are presented.  相似文献   
72.
OBJECTIVE: To elucidate the role of adhesion molecules in the pathogenesis of rheumatoid arthritis (RA). METHODS: We evaluated their expression and that of an activation marker on CD4+ cell populations and CD4+ cell subsets in specimens of peripheral blood (PB) and synovial fluid (SF) obtained from 10 patients with RA and 7 with osteoarthritis (OA). A 2 or 3-color immunofluorescent method was used for analysis. RESULTS: The SF from both groups of patients showed a greater density of adhesion molecules including LFA-1 alpha, LFA-1 beta, CD2, VLA-4 alpha and VLA-5 alpha on CD4+ cells, and a higher percentage of CD4+HLA-DR+ cells compared with their PB. IN PB-CD4+ cell subsets from the arthritic and healthy subjects, the CD4+CD45RO+ cell population showed an increased expression of adhesion molecules compared with CD4+CD45RA+ cell population. The expression of adhesion molecules on circulating CD4+ cell population and CD4+ cell subsets from the patients with RA and OA was comparable to that from healthy subjects. SF from both groups of patients showed a higher percentage of CD4+CD45RO+ cells and a lower percentage of CD4+CD45RA+ cells. In SF-CD4+ cell subsets from patients with RA, the CD4+CD45RO+ cell population had an increased expression of VLA-4 alpha compared to the CD4+CD45RA+ cell population; however, there was no significant difference in other adhesion molecule expression and the percentage of HLA-DR+ cells between the 2 cell subsets. Furthermore, the expression of VLA-4 alpha on the CD4+CD45RO+ cell population in SF from patients with RA was significantly higher than that in matched PB. In CD4+CD45RA+ cell population from both groups of patients, SF showed an enhanced expression of adhesion molecules and an increased percentage of HLA-DR+ cells compared with matched PB. CONCLUSION: Our results suggest that increased expression of adhesion molecules and increased percentage of HLA-DR+ cells on CD4+ cells in SF may be responsible for cellular interactions between these cells and synovial cells or extracellular matrix.  相似文献   
73.
The organization and nucleotide sequence of the capsular gene cluster involved in the biosynthesis of the type 33F capsular polysaccharide of Streptococcus pneumoniae have been determined. The complete type 33F operon (cap33f) is composed of 14 potential open reading frames where the last ten genes are group-specific. Putative functions have been assigned to several gene products by sequence comparison with the proteins included in the databases. A functional promoter located immediately upstream from the first gene of the cap33f gene cluster has been demonstrated. A 20 kb DNA fragment containing the cap33f genes and the operon promoter was sufficient to transform a S. pneumoniae type 3 unencapsulated mutant to the type 33F capsule.  相似文献   
74.
75.
N Yoshioka  S Tominaga 《Canadian Metallurgical Quarterly》1997,47(5):460-5; discussion 465-6
BACKGROUND: Although the most common technique of cerebral revascularization is superficial temporal artery to middle cerebral artery bypass, we occasionally encounter a situation in which the ipsilateral superficial temporal artery is not available. Treatment may require several techniques including long vein graft bypass. METHODS: A 54-year-old man experienced transient ischemic attacks, and cerebral angiography revealed occlusion of the right common carotid artery. Cerebral blood flow study revealed reduced perfusion reserve capacity of the right cerebral hemisphere. We applied an omental free flap to the brain surface using the contralateral superficial temporal vessels as recipient vessels. RESULTS: Cerebral blood flow study revealed improvement of perfusion reserve capacity. Cerebral angiography revealed good collateral circulation from the omentum to the brain. The patient has not experienced a transient ischemic attack, following additional ligation of the occipital artery 13 months after the first operation. CONCLUSIONS: Because an omental flap has a long pedicle and its circulation can be monitored easily, this method is safe and as effective as a long bypass graft in a patient such as ours in whom the ipsilateral superficial temporal artery is not available for anastomoses.  相似文献   
76.
We have synthesized mesoporous silica (MPSi) as a novel type of inorganic filler for polyether-based electrolytes and have characterized the effect of addition on ionic conduction. Both poly(ethylene oxide) (PEO) and PMEO composites filled with MPSi showed higher ionic conductivity than the original and the composites filled with particle silica (pSiO2). It was considered that the increase is caused by the difference in the surface area between MPSi and pSiO2. In the PEO composites, the addition of MPSi gave rise to the reduction of crystal PEO and crystalline complex domains. The glass transition temperature of the PMEO composites increased with the addition of the MPSi, in spite that the conductivity increased with increasing the filler contents. It has been suggested that the Lewis acid-base interactions between ions, ether chains and filler surface strongly affect on the ionic conduction in the composite electrolytes.  相似文献   
77.
We studied the long-term outcome of percutaneous isolated hepatic perfusion (PIHP) for patients with hepatocellular carcinoma. This study included 31 patients with Stage IVA and 5 with IVB disease treated by PIHP until December, 1997. The mean age and tumor diameter were 55 and 7.7 cm, respectively. Twenty-two had portal vein invasion, 13 had hepatic vein invasion, and all patients had multiple intrahepatic metastases of more than 5 tumor foci. The PIHP with adriamycin or cisplatin was undertaken in a total of 50 treatments in these 36 patients. CR was observed in 6 and PR in 13 with an overall response rate of 59%, excluding 4 patients who were not evaluable. Five of 6 patients with CR remain free of disease at 7 to 54 months after the first treatment. The overall survival rate was 67% at 1 year and 32% at 5 years. The survival rates of Stage IVA patients (1-year = 71%, 5-year = 36%) were higher than Stage IVB patients (1-year = 20%, 5-year = 0%). The 5-year survival rates of patients with vascular invasion (Vp1-3 = 23%, Vv1-3 = 8%) were lower than those without it (Vp0 = 47%, Vv0 = 51%). These results indicated that PIHP achieved a 5-year survival rate of approximately 40% in patients with multiple advanced hepatocellular carcinoma in the absence of distant organ metastases and marked vascular invasion, and yielded complete long-term remission in some of these patients.  相似文献   
78.
Mutation of the adenomatous polyposis coli (APC) gene is frequently found in colorectal tumors from both familial adenomatous polyposis (FAP) and non-FAP patients. Analysis of APC mutation is time-consuming and costly due to the large size of the APC gene. As the majority of APC mutations result in the truncation of gene products, the detection of truncated APC proteins may be used as a screening method for APC mutations. The aim of this study is to establish a practical method of detecting truncated APC proteins for the screening of APC mutations. APC proteins in human colorectal cancer cell lines were analyzed by western blotting. Truncated APC proteins were expressed in all of the colorectal cancer cell lines studied. Two species of truncated APC proteins were expressed in two cell lines. Western blotting is a rapid, reliable screening method for APC mutations and provides information on both alleles.  相似文献   
79.
A method to treat lower limb ischemia associated with the insertion of an intraaortic balloon catheter is herein reported. A low dose of prostaglandin E1 was administered into the descending aorta continuously from the tip of the intraaortic balloon catheter. Immediately after the administration of prostaglandin E1 in patients whose lower limbs were ischemic due to obstruction with the catheter, the peripheral circulation of the ischemic limbs recovered with minimal changes in the systemic arterial blood pressure. This method is simple and noninvasive and was found to induce a satisfactory effect.  相似文献   
80.
In this study, morphologic changes in brain lesions initiated by moderate lateral fluid percussion injury in rats were investigated chronologically using high-resolution magnetic resonance imaging (MRI) and histopathologic methods. Rats were subjected to moderate fluid percussion injury (average 2.80 +/- 0.48 atmospheres) over the exposed dura overlying the right parietal cortex. MRI obtained in vivo were compared with corresponding pathologic findings at 1, 6, and 24 h and at 3, 6, 14 and 80 days after injury. T2-weighted images showed scattered low-signal intensity in the injured cortex within a few hours after injury, whereas histologic findings revealed intraparenchymal hemorrhages. T2-weighted images of the ipsilateral cerebral cortex and/or corpus callosum showed a high-signal-intensity area 4 h after injury. The high-signal-intensity area became largest in size between 6 and 24 h, then declined gradually, and almost disappeared 14 days after injury. Histologic examination revealed pyknosis, retraction of the cell body of neurons with vacuolated neuropil in the corresponding regions 6 and 24 h after injury, and cystic necrosis 14 days after injury. The location and extent of these pathologic changes were depicted accurately by MRI in vivo. In the hippocampus, pyknosis and retraction of the cell body of pyramidal neurons were observed on the injured side 24 h after injury, and the number of neurons in the CA1 and CA2-CA3 regions decreased significantly on the same side by 14 days after injury. It is concluded that morphologic changes in the brain following experimental traumatic brain injury in rats are detectable in vivo by high-resolution MRI, and that MRI may be useful for the evaluation of treatment effects in experimental brain injury.  相似文献   
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