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排序方式: 共有690条查询结果,搜索用时 15 毫秒
81.
GG Sheng J Shao H Sheng EB Hooton PC Isakson JD Morrow RJ Coffey Jr RN DuBois RD Beauchamp 《Gastroenterology》1997,113(6):1883-1891
BACKGROUND & AIMS: Constitutive expression of cyclooxygenase 2 (COX-2) has been found in 85% of colorectal cancers. Ras mutations are found in 50% of colorectal adenocarcinomas. The aim of this study was to determine the role of COX-2 in ras-induced transformation in rat intestinal epithelial (RIE) cells. METHODS: Cell growth was determined by cell counts. The expression of COX-2 was examined by Northern and Western analyses. For tumorigenicity assays, cells were inoculated into dorsal subcutaneous tissue of athymic nude mice. DNA-fragmentation assays were performed to detect apoptosis. RESULTS: The expression of COX-2 was increased in RIE-Ras cells at both messenger RNA (9-fold) and protein (12-fold) levels. Prostaglandin I2 levels were elevated 2.15-fold in RIE-Ras cells. Serum deprivation further increased COX-2 expression 3.8-fold in RIE-Ras cells. Treatment with a selective COX-2 antagonist (SC58125) inhibited the growth of RIE-Ras cells through inhibition of cell proliferation and by induction of apoptosis. SC-58125 treatment reduced the colony formation in Matrigel by 83.0%. Intraperitoneal administration of SC-58125 suppressed RIE-Ras tumor growth in nude mice by 60.3% in 4 weeks. SC-58125 treatment also induced apoptosis in RIE-Ras cells as indicated by increased DNA fragmentation. CONCLUSIONS: Overexpression of COX-2 may contribute to tumorigenicity of ras-transformed intestinal epithelial cells. Selective inhibition of COX-2 activity inhibits growth of ras-transformed intestinal epithelial cells and induces apoptosis. (Gastroenterology 1997 Dec;113(6):1883-91) 相似文献
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S. W. MacGowan P. Sidhu T. Aherne D. Luke A. E. Wood M. C. Neligan E. McGovern 《Irish journal of medical science》1993,162(6):223-226
Despite being the most common benign intracardiac tumour with an excellent prognosis after surgical excision the incidence of atrial myxoma (except at autopsy) is unknown. We reviewed all patients admitted to the National Cardiac Surgery Unit (n=26) with an atrial myxoma over a fifteen year period (1977–1991) to compile national incidence data and assess pre-operative diagnosis, management, surgical technique, and outcome. Preoperative symptoms were: congestive cardiac failure (12 patients), embolism (8 patients), constitutional (3 patients), asymptomatic (2 patients) and tachyarrhythmia (1 patient). The diagnosis was confirmed by 2D echocardiography alone in thirteen patients and by a combination of echocardiography and angiography in thirteen patients. At operation the site of the tumour was left atrial in 24 patients and bi-atrial in two patients. All cases were confirmed by histology. All patients made a good post-operative recovery, although one patient survived a pulmonary embolus and one patient developed a deep venous thrombosis. There has been one late death (five months after surgery) from a cerebrovascular accident. Serial echocardiography has revealed one recurrence to date (8 years after surgery). The surgical incidence of these tumours in the Republic of Ireland over the study period was 0.5 atrial myxomas/million population/year. Although rare atrial myxomas are the most important cardiac tumours to diagnose as the results from surgery are excellent. 相似文献
85.
Hepatic spiral CT: reduction of dose of intravenous contrast material 总被引:13,自引:0,他引:13
86.
目的尿液沉渣分析红、白细胞由传统的定性报告方式改为定量分析(××/μl).由于使用的检查方法不同,其参考值也不一样,国内目前尚未有统一的参考值,为使牡丹江市有一个统一的判断标准.方法我们对1109名健康成人其中男性591人,女性518人进行尿中红细胞及白细胞的参考值调查.方法采用国内的专用尿沉渣计数板,显微镜下计数.对体检者在统一时间清晨7点钟留取尿液20~30毫升,按统一操作规程进行操作,对不同性别的人群进行参考值的调查.结果男性红细胞x是1.12,S是1.42,95%可信界限0~3.96,参考值范围0~4/μl;男性白细胞x是1.84,是S 2.05,95%可信界限0~5.94,参考值范围0~6/μl.女性红细胞x是2.46,S是3.26,95%可信界限0~8.98,参考值范围0~9/μl;女性白细胞x是2.25,S是3.82,95%可信界限0~9.89,参考值范围0~10/μl.结论通过1109名正常成人尿液红细胞及白细胞含量的调查,建立了牡丹江市的参考值. 相似文献
87.
Ambulatory sclerotherapy for malignant pleural effusions 总被引:12,自引:0,他引:12
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