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21.
核素显像对小儿消化道出血的病因诊断 总被引:5,自引:0,他引:5
目的探讨核素显像对小儿消化道出血,特别是对Meckel憩室、肠重复畸形的病因诊断的价值。方法对26例腹痛、便血为主要症状的患儿行99m锝酸盐(99mTcO-4)显像,其中12例显像阴性者于检查后24小时有活动性出血者,再行99m锝标记红细胞显像。所有病例的诊断均经手术、病理及内窥镜等检查所证实。结果99mTcO-4显像诊断Meckel憩室和肠重复畸形的敏感性、特异性、准确性分别为85.7%(12/14)、91.7%(11/12)及88.5%(23/26)。结论核素显像具有无创、方法简单易行等特点,特别是对异位胃粘膜诊断具有较好的灵敏性和特异性。核素显像可作为下消化道出血病因诊断的有效方法。 相似文献
22.
通过42例重型肺心病、7例轻型肺心病、16例肺心病伴发冠心病患者和30例正常人在静息状态下的左右心脏射血分数及其临床资料的分析表明,重型肺心病患者在病情的急性发作期,存在有不同程度的左心功能不全,而轻型肺心病患者则无左心功能不全的表现。表明慢性肺心病仅在病程晚期,才由以右心为主的疾病发展成为全心病。本文还对重型肺心病与肺心病伴发冠心病患者的左心功能进行比较,结果表明,肺心病伴发冠心病患者左室功能受损程度更为明显,双重病因导致的左室功能减退,常造成心肌更严重的损害而且不容易恢复。 相似文献
23.
研究深低温停循环(DHCA)与逆行脑灌注(RCP)时脑组织自由基的变化。健康杂种犬14只,随机等分为DHCA组和RCP组,在停循环前(A点)、DHCA/RCP30分(B点)、DHCA/RCP60分(C点)DHCA/RCP90分(D眯)和复温再灌注30分(E点)取脑皮层lg,检测丙二醛(MDA)和超氧化物歧化酶(SOD)水平。结果见两组在A点MDA和SOD无差别。在B、C、D、E点,DHCA组MDA 相似文献
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SK&F 86466, 6-chloro-3-methyl-2,3,4,5-tetrahydro-1-H-3-benzazepine, is a potent and selective antagonist of the α2-adrenoceptor in vitro. This compound produced a small pressor response accompanied by a marked bradycardia when administered i.v. to the pithed normotensive rat. The pressor response was not affected by reserpine treatment, pretreatment with α- or β-adrenoceptor antagonists, atropine, or hexamethonium. The bradycardia was markedly reduced by bilateral vagotomy and pretreatment with atropine and attenuated by hexamethonium. The negative chronotropic action of SK&F 86466 was abolished by a combination of vagotomy and atropine. Mediation of the bradycardia by a baroreceptor reflex was ruled out by the observations that a lack of change in heart rate was associated with the vasopressor response to phenylephrine in the pithed rat pretreated with propranolol. It is concluded that the negative chronotropic action of SK&F 86466 in the pithed rat is mediated indirectly by activation of the cholinergic innervation of the heart. 相似文献
26.
Bobak A. Ghaheri MD Karen J. Fong MD Peter H. Hwang MD 《Otolaryngology--head and neck surgery》2006,134(6):1006-1009
OBJECTIVE: The surgical treatment of epistaxis associated with hereditary hemorrhagic telangiectasia (HHT) is varied. Laser therapy is often inadequate for larger complex lesions. This study sought to determine if bipolar cautery can be effectively and safely used in treating HHT-associated epistaxis. STUDY DESIGN AND SETTING: Records from all patients with HHT treated surgically over 8 years were reviewed retrospectively. Outcomes or complications were noted in the clinic on follow-up evaluation. RESULTS: Twenty-seven patients with HHT who underwent surgical treatment of epistaxis were evaluated; 18 were treated with bipolar cautery. Forty-two separate bipolar treatments were performed. No new septal perforations or synechiae were noted. Twenty-two of 42 treatments were coupled with ancillary laser treatments. The bipolar was also used as the sole technique in 20 procedures. CONCLUSION: Bipolar electrocautery is a safe and effective tool for the intraoperative control of HHT-related epistaxis. SIGNIFICANCE: Bipolar electrocautery may be used as an adjunct to laser techniques or as a stand-alone technique. EBM RATING: C-4. 相似文献
27.
利用特异性DNA倍增技术(polymerase chain Reaction,PCR)检测t-PA cDNA基因在表达细胞基因组中的稳定性,并对所得的PCR反应产物进行了限制性内切酶片段、分子杂交和核苷酸顺序分析等方面的研究,证实了t-PA cDNA基因已插入到表达细胞染色体中。这种方法快速、简便、灵敏度和特异性高,是检测基因工程表达细胞中cDNA基因稳定整合状况的好方法。 相似文献
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29.
Interstitial retinoid binding protein (IRBP) is a 136,000 molecular weight photoreceptor cell protein which is a highly pathogenic autoantigen for the induction of experimental autoimmune uveitis (EAU). In this study we produced a series of monoclonal antibodies (MAbs) which define different epitopes in the native molecule. These MAbs were further subdivided into three distinct groups based on a radioimmunoassay, and by ELISA assay using native IRBP and synthetic peptides corresponding to its entire amino acid sequence. Group I MAbs (MAbD7-B1 and MAbC6-B4) bound to native IRBP but not to any synthetic peptides, suggesting that their antigenic epitopes are strictly conformation dependent. Group II MAbs (MAbC7-D3 and MAbG8-H4) bound weakly to multiple peptides which shared amino acid sequence similarity located within each of four homology domains indicating that these epitopes are also conformation dependent. In group III (MAbH3-B5, MAbH7-A5, and MAbB6-D12) MAb binding was localized to a specific peptide. The MAbH3-B5 binding site was further refined to amino acid positions 361 to 367 in the native molecule. MAbH3-B5 was also useful in localizing IRBP in the mouse retina by immunohistochemical techniques. The application of these MAbs in the study of EAU and interphotoreceptor transport mechanisms is discussed. 相似文献
30.
OBJECTIVE: The authors weighed the risks and benefits of repeat liver resections for colorectal metastatic disease. METHOD: In the 6-year period between January 1985 and June 1991, 499 patients underwent liver resections for colorectal metastases at the Memorial Sloan-Kettering Cancer Center. Of these, 25 patients had repeat surgical resections for isolated recurrent disease to the liver. The clinical data for these patients were reviewed. RESULTS: The median interval between the two resections was 11 months. There were no perioperative deaths, and the complication rate was 28%. Median follow-up after the second liver resection is 19 months, with median survival of 17 months for nonsurvivors. Although the median survival after the second resection is 30 months, 20 of the 25 patients have had recurrences with a median disease-free interval of only 9 months. No characteristic of primary or metastatic disease predicted outcome, including time between presentation of the primary and development of liver metastases, disease-free interval after the first liver resection, and bilobar liver involvement. CONCLUSIONS: Although repeat liver resections can be performed safely and improves survival, the likelihood of cure from such resection therapy is low. This likelihood of further recurrences encourage studies of adjuvant or alternative treatments of this population. 相似文献