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11.
Lead was administred to adult female rats in drinking water (0;0.1:1 and 10 ppm) for 3 weeks before mating, during pregnancy and during 3 weeks after delivery. On day 21 after delivery the mothers and their newborns were sacrified and various parameters of blood -- lead concentration on (Pb-B), hematocrit (Htc), hemoglobin (Hb), free erythrocyte porphyrins (FEP), delta0aminolevulinate dehydratase (ALAD) -- and tissue -- ALAD, free tissue porphyrins (FTP), lead concentration (Pb-T) -- were determined. In mothers a significant increase in Pb-B and Pb concentration in kidney was found in the 10 ppm group, but this increase in lead concentration was not associated with any statistically significant modification of the biochemical parameters. In newborns, lead concentration in blood and in kidney was also significantly increased in the 10 ppm group and this lead exposure was associated with a decrease of the ALAD activity in blood and an increase of FTP in kidney. On the basis of the biochemical parameters investigated one can therefore conclude that the developing organism is more susceptible to the biological action of lead than the organism of adult animals and that the "no-effect" level of lead administered during pregnancy and in the neonatal period is around 1 ppm. 相似文献
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138例已绝经与未绝经子宫内膜癌患者临床病理分析 总被引:1,自引:0,他引:1
目的 回顾研究已绝经与未绝经子宫内膜癌的病理分型,组织分级和手术病理分期等.方法 分析1987年1月~1996年12月上海第一妇婴保健院收治的138例子宫内膜癌患者,其中已绝经者93例,未绝经者45例.所有的病人都进行了分段诊刮,134例经过手术治疗.标本均进行了病理诊断,并根据1988年FIGO标准进行分期,所得资料用X~2Fisher’s exact test分析.结果 已绝经组与未绝经组比较,早期患者(IaG_1)比例明显偏低,分别占6%与32%.(P<0.001).G_2、G_3和非内胰腺癌的发生率是高的,分别是71%和51%(P<0.05).Ⅰc、Ⅱ、Ⅲ、Ⅳ期所占的比例较大,分别是40%和30%(P<0.001).五年生存率:已绝经组为74.2%,未绝经组91.4%,两者比较有明显意义(P<0.05).结论 已绝经子宫内膜癌患者预后较未绝经者差与临床和病理特点有关. 相似文献
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Daniel J. Stein Christian Salinas Saher Sabri Rose Onyeali Stephen Caldwell Zachary Henry 《Journal of vascular and interventional radiology : JVIR》2019,30(2):187-194
Purpose
To assess short- and long-term mortality and rebleeding with endoscopic cyanoacrylate (EC) versus balloon-occluded retrograde transvenous obliteration (BRTO).Materials and Methods
A retrospective cohort comparison was conducted of 90 EC patients and 71 BRTO patients from 1997 through 2015 with portal hypertension who presented due to endoscopically confirmed bleeding cardiofundal gastric varices. Patients underwent either endoscopic intra-varix injection of 4-carbon-n-butyl-2-cyanoacrylate or sclerosis with sodium tetradecyl sulfate with balloon occlusion for primary variceal treatment.Results
Seventy-one BRTO patients and 90 EC patients, of whom 89% had cirrhosis and 35% were women, were included, with a respective average Model for End-Stage Liver Disease (MELD) score of 13.4 and 14.4, respectively. Mortality at 6 weeks was 14.4% for EC patients and 13.1% for BRTO patients (Kaplan-Meier/Wilcoxon, P = .85). No long-term mortality difference was observed (Cox hazard ratio [HR] = 0.89, P = .64). Also, 5.1% of EC patients and 3.5% of BRTO patients (Kaplan-Meier/Wilcoxon, P = .62) rebled at 6 weeks, but at 1 year, 22.0% of EC patients and 3.5% of BRTO patients had rebled (Kaplan-Meier/Wilcoxon, P < .01). Lower rates of long-term rebleeding were found with BRTO (Cox HR = 0.25, P = .03). No difference was seen in the rate of new portal hypertensive complications (Cox HR = 1.21, P = .464). However, 16/71 patients who underwent BRTO had simultaneous transjugular intrahepatic portosystemic shunt. Age, sex, MELD score, and presence of cirrhosis were the primary predictors of mortality. One death in the EC group and 5 deaths in the BRTO group were deemed to be procedurally related (chi-square, P = .088).Conclusions
BRTO is associated with a lower rate of rebleeding but no change in mortality. 相似文献16.
Understanding the societal impact and trends of coronary heart disease through basic epidemiological measures is essential to evaluate treatment effectiveness and organize resource distribution. In the following narrative review, data are presented on the prevalence, incidence, and prognosis of coronary heart disease in general and of acute coronary syndrome in particular. 相似文献
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Hybrid imaging for ischemic heart disease refers to the fusion of information from a single or usually from multiple cardiovascular imaging modalities enabling synergistic assessment of the presence, the extent, and the severity of coronary atherosclerotic disease along with the hemodynamic significance of lesions and/or with evaluation of the myocardial function. A combination of coronary computed tomography angiography with myocardial perfusion imaging, such as single-photon emission computed tomography and positron emission tomography, has been adopted in several centers and implemented in international coronary artery disease management guidelines. Interest has increased in novel hybrid methods including coronary computed tomography angiography-derived fractional flow reserve and computed tomography perfusion and these techniques hold promise for the imminent diagnostic and management approaches of patients with coronary artery disease. In this review, we discuss the currently available hybrid noninvasive imaging modalities used in clinical practice, research approaches, and exciting potential future technological developments. 相似文献
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Molecular defects in mucosal serotonin content and decreased serotonin reuptake transporter in ulcerative colitis and irritable bowel syndrome 总被引:45,自引:0,他引:45
Coates MD Mahoney CR Linden DR Sampson JE Chen J Blaszyk H Crowell MD Sharkey KA Gershon MD Mawe GM Moses PL 《Gastroenterology》2004,126(7):1657-1664
BACKGROUND & AIMS: Serotonin (5-HT) is a critical signaling molecule in the gut. 5-HT released from enterochromaffin cells initiates peristaltic, secretory, vasodilatory, vagal, and nociceptive reflexes. Despite being pathophysiologically divergent, ulcerative colitis (UC) and irritable bowel syndrome (IBS) are both associated with clinical symptoms that include alterations in the normal patterns of motility, secretion, and sensation. Our aim was to test whether enteric 5-HT signaling is defective in these disorders. METHODS: Rectal biopsy specimens were obtained from healthy controls and patients with UC, IBS with diarrhea (IBS-D), and IBS with constipation (IBS-C). Key elements of 5-HT signaling, including measures of 5-HT content, release, and reuptake, were analyzed with these samples. RESULTS: Mucosal 5-HT, tryptophan hydroxylase 1 messenger RNA, serotonin transporter messenger RNA, and serotonin transporter immunoreactivity were all significantly reduced in UC, IBS-C, and IBS-D. The enterochromaffin cell population was decreased in severe UC samples but was unchanged in IBS-C and IBS-D. When 5-HT release was investigated under basal and mechanical stimulation conditions, no changes were detected in any of the groups relative to controls. CONCLUSIONS: These data show that UC and IBS are associated with similar molecular changes in serotonergic signaling mechanisms. While UC and IBS have distinct pathophysiologic properties, these data suggest that shared defects in 5-HT signaling may underlie the altered motility, secretion, and sensation. These findings represent the first demonstration of significant molecular alterations specific to the gut in patients with IBS and support the assertion that disordered gastrointestinal function in IBS involves changes intrinsic to the bowel. 相似文献
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Mycotoxins are secondary metabolites produced by fungi contaminating the food chain that are toxic to animals and humans. Children up to 12 years old are recognized as a potentially vulnerable subgroup with respect to consumption of these contaminants. Apart from having a higher exposure per kg body weight, they have a different physiology from that of adults. Therefore they may be more sensitive to neurotoxic, endocrine and immunological effects. For these reasons, a specific and up-to-date risk analysis for this category is of great interest.In this review, an accurate analysis of the main mycotoxins occurring in food intended for children (deoxynivalenol, aflatoxins, ochratoxins, patulin and fumonisins) is presented. In particular, known mechanisms of toxicity and levels of exposure and bioaccessibility in children are shown. In addition, recent discoveries about the strategies of mycotoxins managing are discussed. 相似文献