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111.
目的:研究β趋化因子受体5(CCR5)NH2端膜外第一襻结构域的功能及其特异抗体F(ab′)2的制备。方法:计算机分析趋化因子超基因家族,定位超基因家族中同源顺序最低的结构域NH2端膜外结构域,PCR扩增出该结构域114个核苷酸序列。构建融合表达载体pGEX-IN/NR5,经测序鉴定正确后,在E.coli中表达,经纯化后免疫新西兰兔。蛋白A亲和层析和胰蛋白酶消化IgG,经Sepharose-12柱层析制备F(ab′)2。结果:经还原和非还原聚丙烯酰胺凝胶电泳和FAX分析证明得到抗CCR5NH2端的特异性抗体。结论:本方法为一简捷快速的特定功能结构域抗体F(ab′)2制备方法,对研究该基因在体内的表达及生物学功能提供了重要的实验材料,同时也对超基因家族中亚家族特异抗体研制提供了一种研究思路和方法。  相似文献   
112.
113.
Objective  Exposure to polychlorinated biphenyls (PCBs) is considered to have culminated between 1950 and 1970 in Japan, and exposure through diet, the major exposure route, has decreased significantly over the last 10 years. The primary goal of the present study was to investigate the long-term trends and congener profiles of serum and dietary levels of PCBs using historical samples. Methods  Using banked samples collected in 1980, 1995, and 2003 surveys, we determined the daily intakes and serum concentrations of 13 PCB congeners (#74, #99, #118, #138, #146, #153, #156, #163, #164, #170, #180, #182, and #187) in women. Results  The total daily PCB intake [ng/day, geometric mean (geometric standard deviation)] decreased significantly from 523 (2.5) in 1980 to 63 (3.2) in 2003. The serum total PCB level (ng/g lipid) in women <40 years of age decreased significantly from 185 (1.8) in 1980 to 68 (1.8) in 2003. In contrast, the level in women >50 years of age increased significantly from 125 (1.7) in 1980 to 242 (1.7) in 2003. Specifically, the serum concentrations of hexa (#138, #146, #153, #156, #163, and #164) and hepta (#170, #180, #182, and #187) congeners increased significantly. A comparison of the serum PCB levels of women born from 1940 to 1953 revealed that their serum total PCB level was significantly higher in the 2003 survey [242 (1.7), n = 9] than in the 1995 [128 (2.0), n = 17] surveys. This increase in the total PCB level was attributable to increases in the hepta congener groups. Conclusion  Present results suggest a decreased rate of elimination of hepta congeners with aging in females, rather than a birth-generation phenomenon.  相似文献   
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115.
Combined chemotherapy including 5-FU plus radiation treatment resulted in a synergistic effect has been reported. S-1 enhances a radiation response of colon cancer cell line xenografts. Also the effectiveness of S-1 + radiation therapy has been reported. A 66-year-old man underwent a low anterior resection for lower rectal cancer. Adjuvant chemotherapy was not performed due to Stage II rectal cancer. Twenty months after the operation, solitary sacral bone metastasis was found during the postoperative work-up. S-1 (120 mg/day) combined with radiotherapy was performed on days 1-14 and 21-35. Radiation (3 Gy) was administered a total of 45 Gy on days 1-5, 7-12 and 35-40. Moreover, the reduction was judged as complete response after 11 courses of mFOLFOX 6. There has been no sign of recurrence for 44 months. It suggested that local control therapy (S-1 + radiation) plus systemic chemotherapy (mFOLFOX6) was one of the promising effective therapies for single sacral bone metastasis of rectal cancer.  相似文献   
116.
We describe here a case of accidental electrocution. A 48-year-old male was found dead in his room. At autopsy, there was a current mark on the right thumb and big toe. Histological examination revealed that the skin wound had the characteristics of a current mark, including vacuolation and elongation of the cell nuclei. We could also identify titanium metallization on the skin surface of the current mark using a variable-pressure scanning electron microscope (VP-SEM) equipped with energy dispersive X-ray microanalyser (EDX). The autopsy finding and the subsequent investigation support the conclusion that the cause of his death was electrocution. Our result shows that the VP-SEM with EDX is a useful tool for the forensic diagnosis of electrocution.  相似文献   
117.
We have examined the utility of DDC as a novel marker for the detection of peritoneal micrometastases of gastric cancer. DDC mRNA in the peritoneal wash from 114 gastric cancer patients was quantified for a comparison of carcinoembryonic antigen (CEA) mRNA by means of real-time RT-PCR with a fluorescently labeled probe to predict peritoneal recurrence. The cut-off value was set at the upper limit of the quantitative value for non-cancer patients, and those above this cut-off value constituted the micrometastasis (MM+) group. Thirteen of 15 cases with peritoneal dissemination were MM+DDC (87% sensitivity), and one of 48 t1 cases was MM+ (98% specificity). DDC levels in peritoneal washes from patients with synchronous peritoneal metastases were more than 50 times higher than in those from patients without metastasis (p<0.01). For 15 cases of peritoneal dissemination (seven cases were cytologically positive), DDC was positive in 13 cases (87% sensitivity), but CEA failed to detect micrometastases in four cases (73% sensitivity), indicating that DDC is in some cases superior to CEA for the detection of peritoneal micrometastases of gastric cancer in terms of sensitivity as well as specificity, especially for poorly differentiated adenocarcinomas. Combination of CEA and DDC improved the accuracy of diagnosis up to 93%. These results suggest that DDC is potentially a novel marker for peritoneal dissemination of gastric cancer and that quantitative RT-PCR of DDC is reliable and efficient for the selection of patients for adjuvant intraperitoneal chemotherapy to prevent peritoneal recurrence.  相似文献   
118.
A 59-year-old man with cardiac dysfunction was admitted to our hospital because of thrombus formation in the left ventricle 10 days following acute myocardial infarction. Echocardiography revealed evidence of two mobile thrombi, each measuring about 2 cm in diameter. Urgent coronary artery bypass grafting and video-assisted transaortic thrombectomy were performed without making a left ventricular incision to preserve his cardiac function. Endoscopy was useful for visualizing the anatomical structures in the left ventricular cavity.  相似文献   
119.
Abstract: The long-term effect of percutaneous transhepatic choledochoscopic YAG laser therapy for malignant biliary tract obstruction was evaluated. Ten consecutive patients underwent laser therapy to alleviate the obstruction. All patients were followed up for 8 months or more (range: 8–33 month, average: 15). Cholangiography was performed when re-elevation of the alkaline phosphatase level was observed during the regular checkup. Choledochoscopy was performed when any sign of recurrence was observed on cholangiography. Sufficient re-opening of the bile duct was obtained in every case, without complications. Indwelling of the internal drainage tube was perfomed in 5 patients, the remaining 5 having “tube free” internal drainage. Five patients showed no rise in alkaline phosphatase levels during their 8- to-13 month follow-up period. Re-elevation of the alkaline phosphatase level was observed 9 times in 5 patients, mostly from internal drainage tube occlusion. The cholangiogram performed on each occasion revealed a patent bile duct without any sign of recurrence (6/9), slight narrowing (2/9) or tumorous obstruction (1/9). Cholangitis was complicated 6 times in 3 patients, mostly from internal drainage tube occlusion. Choledochoscopy was performed in the 3 patients suspected of tumor recurrence on cholangiogram. In 2 of them, no signs of recurrence were noted endoscopically or histologically, but the tumor was revealed to have recurred only at the part previously treated, in the remaining. Thus, choledochoscopic I'AG laser therapy can locally control the malignant biliary tract obstruction for a long period of time. “tube free” internal drainage may serve as a means to prevent cholangitis, which is one of the complications frequently occurring with conventional stent therapy.  相似文献   
120.
We performed an endoscopic study of the acute gastric lesions induced by transcatheter arterial embolization (TAE) and infusion chemotherapy (one shot infusion: OSI). Forty-eight patients with primary hepatocellular carcinoma were investigated, and of them, 25 received TAE and 23 were treated with OSI. Endoscopy was performed within 1 week both before and after therapy and any gastric mucosal changes were noted. Before treatment, all patients had gastric lesions such as redness, erosion, hemorrhage and ulcer. These lesions were exacerbated or new lesions appeared after both TAE and OSI in about 50% of the subjects, and no significant difference in the incidence of lesions was observed between these two treatments. Moreover, there was no significant correlation between the exacerbation or new appearance of gastric lesions and the Child's classification, the catheter position, or the presence or absence of A-P shunt or portal thrombus. The appearance and/or exacerbation of these gastric lesions was not prevented by the administration of common antiulcer drugs before treatment. Thus the possibility that these gastric effects of TAE and OSI may occur should always be kept in mind and appropriate preventive or therapeutic measures should be adopted.  相似文献   
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