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991.
C4 concentrations and C4 deficiency alleles in systemic lupus erythematosus. 总被引:1,自引:0,他引:1
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In a study of 66 patients with systemic lupus erythematosus (SLE) and 80 controls it was found that the presence of two deficiency (null) alleles of C4 had a significant effect on mean C4 concentrations in serum. In six controls who each had two C4 null alleles the mean C4 concentration in serum was 56% lower than in 43 controls without C4 null alleles; the nadir of the C4 concentration in four patients with SLE with two null alleles was also lower by a mean of 55% than in 32 patients who did not have null alleles. Reduced production of C4 allotypes in subjects with two null alleles may be an important determinant of total C4 concentration in patients with SLE. For optimal interpretation of C4 concentrations in SLE, C4 allotyping appears to be indicated, particularly to identify patients who have two null alleles of C4. 相似文献
992.
Intestinal infarction caused by carcinoid associated elastic vascular sclerosis: early presentation of a small ileal carcinoid tumour. 总被引:2,自引:1,他引:1
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We describe a patient with extensive ischaemic necrosis of the ileum as a result of elastic vascular sclerosis (EVS). A 2 cm carcinoid tumour was located nearby with microscopic evidence of spread to regional lymph nodes. Severe intestinal ischaemia caused by carcinoid associated EVS may be the presenting feature of small carcinoid tumours resulting in their early diagnosis. 相似文献
993.
The activation of phospholipase A2 is believed to have an important role in the inflammatory process owing to its induction of eicosanoids, platelet activating factor, and other mediators. Soluble phospholipase A2 has been associated with exudates in different inflammatory conditions. In this review the general physiology and control of this enzyme and, in particular, the most recent findings on human synovial fluid phospholipase A2s are discussed. 相似文献
994.
995.
HPLC法测定欣康胶囊中次乌头碱含量 总被引:3,自引:0,他引:3
目的测定欣康胶囊中次乌头碱的含量。方法采用反相高效液相法,以C18为固定相,甲醇-水-三乙胺(75∶25∶0.05)为流动相,检测波长为232nm。结果平均回收率为94.65%,RSD为3.54%。结论方法简便,准确。 相似文献
996.
997.
998.
Meg Sears C Robin Walker Richard HC van der Jagt Paul Claman 《Paediatrics & child health》2006,11(4):229-234
Pesticide regulation is examined in the context of Health Canada’s Pest Management Regulatory Agency’s assessment of the chlorophenoxy herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) for turf. 2,4-D is the most common herbicide used to kill weeds in grass.The medical literature does not uniformly indicate harms from herbicides. However, the balance of epidemiological research suggests that 2,4-D can be persuasively linked to cancers, neurological impairment and reproductive problems. These may arise from 2,4-D itself, from breakdown products or dioxin contamination, or from a combination of chemicals.Regulators rely largely on toxicology, but experiments may not replicate exposures from 2,4-D application to lawns because environmental breakdown products (eg, 2,4-dichlorophenol) may not accumulate and selected herbicides are possibly less contaminated. Dioxins are bioaccumulative chemicals that may cause cancer, harm neurological development, impair reproduction, disrupt the endocrine system and alter immune function. No dioxin analyses were submitted to the Pest Management Regulatory Agency, and the principal contaminants of 2,4-D are not among the 17 congeners covered in pesticide regulation. Independent assessment of all dioxins is needed, in tissues and in the environment.The 2,4-D assessment does not approach standards for ethics, rigour or transparency in medical research. Canada needs a stronger regulator for pesticides. Potentially toxic chemicals should not be registered when more benign solutions exist, risks are not clearly quantifiable or potential risks outweigh benefits. Until landscaping pesticides are curtailed nationally, local bylaws and Quebec’s Pesticide Code are prudent measures to protect public health. Physicians have a role in public education regarding pesticides. 相似文献
999.
1000.
目的探讨基质金属蛋白酶-2(matrix metalloproteinase-2,MMP-2)和环氧合酶-2(cyclooxygenase.2,COX.2)蛋白在非小细胞肺癌组织中的表达与意义。方法应用免疫组化SP方法检测80例非小细胞肺癌组织中MMP-2,COX-2的表达。结果MMP2及COX-2的阳性率分别为31.25%、41.25%。MMP-2及COX-2蛋白表达与临床病理因素无相关性。MMP2和COX-2的阳性表达之间无相关性。结论MMP2及COX-2参与非小细胞肺癌的发生,然而它们也许并不能作为重要的预后指标。 相似文献