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91.
Non-ionic contrast media (CM) are proven to be significantly safer than the high osmolar ionic contrast media (HOCM). Nevertheless deaths are reported after administration of non-ionic agents. The aim of the study was to investigate the rate of adverse reactions to non-ionic CM with special regard to high-risk patients and the effects of premedication with H1-and H2-receptor antagonists.In a prospective study conducted over about 2 years 12 995 examinations with intravenous or intra-arterial non-ionic CM were evaluated. Premedication with H1-and H2-antagonists was used in 1276 high-risk patients with known adverse reaction to CM, history of allergy or severe cardiac or pulmonary disease. 229 patients received no premedication inspite of known risk factors. In total, there were 143 (1.10%) adverse reactions (mild in 0.58%, moderate in 0.41% and severe in 0.05%). In high-risk patients there were adverse reactions in 4.37% without and in 1.57% with premedication. There were no severe adverse reactions in the high-risk patients after premedication. The age of the patient, CM dosage and CM concentration were not shown to be risk factors in the present study. In conclusion, the additional premedication with H1- and H2-antagonists could be an effective agent to reduce the risk of mild and moderate adverse reactions and to avoid severe adverse reactions in high-risk patients.
Correspondence to: U. Fink 相似文献
92.
93.
P. Andersson K. LeBlanc B-. Eriksson J. Samuelsson 《European journal of haematology》1997,59(5):310-317
Abstract: Polycythaemia vera (PV) is a myeloproliferative disorder characterized by haematopoietic progenitor cells being hypersensitive to cytokines such as erythropoietin, interleukin-3, stem cell factor and insulin-like growth factor 1, which results in an increased production of mature blood cells. The pathogenetic cellular mechanism(s) behind this hypersensitivity to cytokines is unknown, but the number of cytokine receptors and the interaction between ligand and receptor are normal in PV. Interest has therefore focused on post-receptor mechanism(s). Haematopoietic cell phosphatase (HCP) is an intracellular tyrosine phosphatase that has been demonstrated to regulate proliferative signals negatively induced by the cytokines mentioned above. Moreover, motheaten mice that genetically lack HCP have an increased amount of erythroid progenitors that are hypersensitive to Epo, and patients with familial polycythaemia have been shown to exhibit a mutation of the Epo receptor gene that includes the docking site for HCP. We therefore studied mRNA expression of HCP in pure populations of CD34+ cells, granulocytes, platelets and lymphocytes from patients with PV, chronic myeloid leukaemia (CML) or essential thrombocythemia (ET), as well as healthy controls. Using a polymerase chain reaction analysis employing specific primers for HCP, we failed to detect any abnormalities of HCP expression in PV in any of the cell populations that were examined. Moreover, HCP mRNA expression was similar in ET and CML compared to controls. Finally, Western blot analysis revealed a normal HCP protein content in PV granulocytes and platelets. We therefore conclude that neither an impaired expression of the HCP gene nor a defect in HCP protein synthesis is present in PV, and does not seem to play a role in the aetiology of this disorder. 相似文献
94.
J. Lepeintre H. Briandet F. Moussy D. Chicheportiche S. Darquy J. Rouchette P. Imbaud J. J. Duron G. Reach 《Artificial organs》1990,14(1):20-27
In bioartificial pancreatic systems, isolated islets of Langerhans are protected against immune rejection by an artificial membrane, permeable to glucose and insulin, but not to immunoglobulins and lymphocytes. Some of these devices, referred to as vascular systems, are set up to be connected to a vascular site in the recipient, with blood circulating in contact with one side of the membrane, and the islets on the other side. Such a bioartificial pancreas, containing isolated rat islets of Langerhans, was connected to an arteriovenous shunt of a normal anesthetized dog. The aim of this experiment was to investigate the kinetics of the insulin secretory response of the system to a glucose load. Glucose was infused upstream of the system, increasing the glucose concentration inside the bioartificial pancreas from 7 to 14 mmol/l, without altering the blood glucose concentration of the dog. Insulin concentration was determined simultaneously upstream and downstream of the bioartificial pancreas. Insulin production was calculated by multiplying the difference between these values by the blood flow rate. Blood flow rate (Q) was estimated from the change in the glucose concentration produced by the glucose infusion using a mass transfer analysis derived from Fick's principle. Insulin production increased from 20 +/- 8 to 59 +/- 15 microU/100 islets/min within 15 min following the beginning of the stimulation (n = 6, p less than 0.05). Five min after the end of the stimulation, insulin production decreased from 75 +/- 13 to 50 +/- 9 microU/100 islets/min (p less than 0.05) to reach the basal level (21 +/- 3 microU/100 islets/min) 30 min after the end of the glucose stimulation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
95.
D. Schiffer M.T. Giordana P. Cavalla M.C. Vigliani A. Attanasio 《International journal of developmental neuroscience》1993,11(2)
The astrocytic reaction in the rat after brain injury has been studied immunohistochemically for intermediate filaments (GFAP and vimentin), also with double staining procedures, and for markers of proliferation (BrdU and PCNA). GFAP-positive reactive astrocytes appeared around the lesion, where they were vimentin-positive and at a distance. BrdU and PCNA showed a high labelling index around the wound at day 2 and scattered positive nuclei were also found at a distance in the ipsilateral side. BrdU-positive astrocytes represented a minor fraction of GFAP- and vimentin-positive astrocytes. The expression of vimentin persisted at least 15 days after the lesion. Our results could suggest that distant reactive astrocytes originate through hypertrophy while those close to lesion arise by hyperplasia from mature or immature glial cells. The hypothesis is formulated that cells of the periventricular matrix contribute to the post-traumatic proliferative activity. 相似文献
96.
以聚合酶链反应(PCR)法在mRNA水平检测T淋巴细胞受体α链可变区基因表达为例,介绍用~(32)P标记的人工合成寡核苷酸探针对PCR产物特异性作阳性证实的方法。该法以干琼脂糖凝胶作为支持物、相对较为简便和省财。用Ca探针以干凝胶作支持物的杂交结果,证实29个Vα基因的PCR扩增中物均为特异性的,放射自显影的带型与位置和溴乙锭染色所示完全吻合。 相似文献
97.
98.
在温度220~260°C,压力5MPa,转筐转速2600r/min,空速1000~2000mL/(g·h)条件下,建立了工业级双功能混合催化剂上含氮合成气直接制二甲醚的宏观动力学模型,并获得了模型参数。统计检验和残差分析表明模型可靠。根据获得的宏观动力学及本征动力学的模拟计算,比较了两模型下温度及含氮量对反应的影响。由于含氮量影响反应组分的分压,进而影响CO的转化率,还通过影响反应组分在催化剂颗粒内的内扩散来影响产物的选择性,但总的结果是内扩散的存在减弱了催化剂的协同效应。 相似文献
99.
100.
子宫内膜癌组织中p16 mRNA及P16蛋白的表达 总被引:7,自引:3,他引:4
①目的 探讨抑癌基因 p16与子宫内膜癌发生、发展的关系。 ②方法 应用逆转录聚合酶链反应(RT PCR)和免疫组织化学技术 ,对 4 2例子宫内膜癌及 15例正常子宫内膜组织中 p16mRNA及P16蛋白进行检测 ,并结合临床病理特征进行分析。③结果 子宫内膜癌组织中p16mRNA及P16蛋白的阳性表达率分别为6 9.0 5 %和 5 9.5 2 % ,显著低于正常组织 (χ2 =6 .0 15、8.6 2 5 ,P <0 .0 5 )。p16mRNA及P16蛋白的表达缺失与肿瘤的组织学类型无关 (χ2 =0 .10 0、0 .2 94 ,P >0 .0 5 ) ,而与组织学分级和临床分期有关 (χ2 =3.95 4、6 .873,P <0 .0 5 )。④结论 p16mRNA和P16蛋白的表达缺失在子宫内膜癌的发生和发展中可能起重要作用 相似文献