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Although many monoclonal antibodies have been made in human colon cancer, none of them are from the Chinese species. Recently, a colon cancer cell line CC-M2 established from a Chinese patient has been completely characterized and used as immunogen to produce monoclonal antibodies. Monoclonal antibodies were produced by standard hybridoma technique. The fusion rate was 95.8%. An isotype IgG1 of high proliferation named as Sam-2 was used in this study. The titers were measured around 10(4). Further studies on MoAb Sam-2 through indirect immunofluorescent and immunoperoxidase tests revealed its good specificity and sensitivity in colorectal cancer tissue. In CEA study, the result indicated that Sam-2 may react on a non-CEA related antigen. For further clinical application, the antigen was identified as a glycoprotein by chemical resistant test. In preliminary studies using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting techniques, Sam-2 could recognize two closed antigens or a dimer antigen with molecular weight 25.2 and 27 Kd respectively. 相似文献
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Harbhej Singh Jay Yang Katina Thornton Adolph H. Giesecke 《Journal canadien d'anesthésie》1995,42(11):987-991
The purpose of investigation was to study the effect of intrathecal fentanyl on the onset and duration of hyperbaric bupivacaine-induced spinal block in adult male patients. Fortythree patients undergoing lower extremity or genitourinary surgery were enrolled to receive either 13.5 mg hyperbaric bupivacaine 0.75% + 0.5 ml CSF it, (Group I) or 13.5 mg hyperbaric bupivacaine 0.75% + 25 μg fentanyl it, (Group II) according to a randomized assessor-blind protocol. The onset and duration of sensory block were assessed by pinching the skin with forceps in the midclavicular line bilaterally every two minutes for first twenty minutes and then every five to ten minutes. Similarly, the onset and duration of motor block were assessed and graded at the same time intervals using the criteria described by Bromage. The time required for two sensory segment regression and sensory regression to L1 dermatome was 74 ± 18 and 110 ± 33 min vs 93 ± 22 and 141 ± 37 min in Groups I and II, respectively (P < 0.05). Intrathecal fentanyl did not enhance the onset of sensory or motor block, or prolong the duration of bupivacaine-induced motor spinal block. Fewer patients demanded pain relief in the fentanyl-treated group than in the control group in the early postoperative period (19% vs 59%; P < 0.05). Episodes of hypotension were more frequent in the fentanyl-treated group than in the control group (43% vs 14%; P < 0.05). We conclude that fentanyl, 25 μg it, prolonged the duration of bupivacaine-induced sensory block (sensory regression to L1 dermatone) by 28% and reduced the analgesic requirement in the early postoperative period following bupivacaine spinal block. 相似文献
166.
Serial peritoneal macrophage function studies in new and established continuous ambulatory peritoneal dialysis patients 总被引:1,自引:0,他引:1
Peritoneal macrophages (PM) perform first-line defense activity against peritonitis, the most important complication in continuous ambulatory peritoneal dialysis (CAPD) therapy. Our longitudinal study has compared the PM function in 20 uremic patients during periods free of peritonitis since they started CAPD therapy in January 1987. The results showed that at the initiation of CAPD, there was a higher bactericidal activity, phagocytosis index, H2O2 production and interleukin-1 (IL-1), gamma-interferon (IFN-gamma) and tumor necrosis factor (TNF) production ability and MHC expression. As time went on, these progressively decreased, and by 9 months after CAPD therapy had started they were significantly lower than at the beginning. During the 1.5-year follow-up period, there was a significantly increased peritonitis rate in the period 6 months after the beginning of CAPD than in the period before the 6th month (88.3 vs. 11.7% respectively; p less than 0.001). These results indicate that PM of new CAPD patients have a more active function than those of established patients. The established patients had a greater risk of peritonitis. A comparison of the immunological profiles of PM from patients who had a peritonitis history shows that phagocytosis index, bactericidal activity and IL-1 and TNF production of PM were significantly decreased during the period free of peritonitis. This result suggests that these parameters may serve as an indicator in developing peritonitis. 相似文献
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本文报告动脉粥样硬化(AS)形成和消退研究的部分工作。在复制AS形成和消退模型的基础上,研究了AS形成和消退中的内皮细胞、平滑肌细胞和单核细胞的改变。 相似文献
169.
Calcitonin gene-related peptide (CGRP) causes vasorelaxation in rat aorta involving endothelium/nitric oxide (NO)-dependent elevations of both cAMP and cGMP levels. When endothelium is removed, preincubation with exogenous NO uncovers and potentiates direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP. This enhancing effect of NO potentially involves elevation of cGMP and inhibition of Type III (cGMPinhibitable) phosphodiesterase, causing accumulation of cAMP. However, NO may have other actions. The aim of the present study was to determine if brain natriuretic peptide (BNP), which elevates cGMP levels independent of NO, could enhance cAMP accumulations and vasorelaxations induced by CGRP in rat aortic rings denuded of endothelium. When added separately, neither CGRP (100 nM) nor BNP (10 nM) altered cAMP levels. When added in combination, CGRP (100 nM) and BNP (10 nM) significantly elevated cAMP levels (from control of 0.95 ± 0.08 to 1.53 ± 0.09 pmol/mg protein) at 2 min. BNP (10 nM) elevated cGMP levels 10-fold at 2 min and this response was not altered by co-administration of CGRP (100 nM).Pretreatment with BNP at concentrations as low as 1 nM in endothelium-denuded aortic rings greatly enhanced the direct vasorelaxant effects of CGRP (100 nM) (from control of 0% to 57.6 ± 6.8% relaxation of phenylephrineprecontractions). Our findings indicate that BNP enhances direct (endothelium-independent) cAMP elevations and vasorelaxations caused by CGRP in rat aorta, thus supporting the concept that cGMP inhibits cAMP metabolism and enhances CGRP-induced responses in aortic smooth muscle cells. 相似文献
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