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781.
Mercury (Hg) concentration in fish depends on feeding strategies and age/size within the species as well as on water parameters related to acidity and Hg speciation. We chose two species of piranhas (Serrasalmus aff. eigenmanni and Serrasalmus rhombeus) to test their suitability as markers of Hg bioaccumulation. The results of Hg concentrations in piranhas of the Rio Negro, with no history of gold-mining activity, are similar to other Amazonian rivers with intensive gold mining. An increase in water Hg associated with low pH favored higher mean Hg concentrations in the two species. S. rhombeus in this habitat showed a consistently higher Hg concentration than S. eigenmanni. This result was attributed to fish size because of differences in correlation coefficient between S. rhombeus (r = 0.4443; P < 0.0001) and S. eigenmanni (r = 0.1520; P = 0.0135). Matching for fish weight resulted in comparable ranges of Hg concentrations between the two species.  相似文献   
782.
783.
The association of zinc and vitamin A levels was studied in liver of foetuses and infants which were stillborn or died of various causes between the age of 26 weeks of gestation up to 16 weeks post-partum. No correlation between zinc and vitamin A was observed (r = 0.07). Although smaller infants had more hepatic vitamin A than larger infants no significant difference was observed between these groups for liver zinc values.  相似文献   
784.
The authors review the neural pathways mediating nociceptive flexion reflexes, the method for analyzing these reflexes in human beings, and available data on their modulation by supraspinal, opioid as well as serotonergic systems. They present results of studies of the biceps femoris flexion reflex (RIII) in pain syndromes and various types of headache. Nociceptive flexor reflexes appear to be interesting for studying the pathophysiology of head pain mechanisms and possibly for evaluating analgesic treatment.  相似文献   
785.
BACKGROUND: We describe a 20-year old woman with retarded healing after a melanoma excision. After short time application of several creams containing antiseptic, antibiotic and anti-inflammatory ingredients she developed a severe contact dermatitis. Patch testing revealed sensitizations against corticosteroids, an antibiotic and quinoline. CONCLUSION: In our case multiple relevant contact sensitizations appeared within a short period of two months after excision of a malignant tumour.  相似文献   
786.
Abstract Nephrotoxicity represents a serious side-effect of immunosuppression following orthotopic liver transplantation. In order to preserve the therapeutic potential of cyclosporin (CsA) and FK 506 in human liver transplantation and to differentiate the nephrotoxic action of either drug in a clinical setting, we evaluated the incidence of early and late nephrotoxicity in 121 patients, 60 randomly assigned to CsA- and 61 to FK 506-based immunosuppression. Early postoperative renal insufficiency (between PODO and 30; SCr 1.5-3 mg/dl) was observed to a similar extent in patients treated with CsA (36.7%) and FK 506 (42.6%). Early postoperative acute renal failure (ARF; SCr > 3 mg/dl) occurred in 18.3%, regardless of the immunosuppressive management. Approximately 50% of patients with ARF required hemodialysis (CsA: 11.7%; and FK 506: 8.3%). Mean onset of hemodialysis in CsA-treated patients was POD1 and in FK 506-treated patients, POD 6, which demonstrated a different time course of drug-pecific nephrotoxicity of CsA and FK 506 in early ARF. All patients with early postoperative ARF requiring hemodialysis survived more than 1 year (100% survival). New onset of late ARF (between POD 30 and 365), however, occurred in 6.5% under FK 506 and in 1.7% under CsA immunosuppression due to severe infections with the multiple organ failure syndrome. This observation was consistent with the assumption of overimmunosuppression rather than a primary nephrotoxic effect. Mortality of patients with late ARF requiring hemodialysis was 100%. Late renal insufficiency appeared in 23.3% of CsA- and in 29.4% of FK 506-treated patients, and represented a slowly progressing form of drug-pecific nephrotoxicity. These preliminary results demonstrated a similar outcome in terms of early and late nephrotoxicity, but longer follow-up will delineate its overall efficacy and toxicity in humans.  相似文献   
787.
Research conducted predominantly in male populations on physical activity and lung cancer has yielded inconsistent results. We examined this relationship among 416,277 men and women from the European Prospective Investigation into Cancer and Nutrition (EPIC). Detailed information on recent recreational, household and occupational physical activity, smoking habits and diet was assessed at baseline between 1992 and 2000. Relative risks (RR) were estimated using Cox regression. During 6.3 years of follow-up we identified 607 men and 476 women with incident lung cancer. We did not observe an inverse association between recent occupational, recreational or household physical activity and lung cancer risk in either males or females. However, we found some reduction in lung cancer risk associated with sports in males (adjusted RR = 0.71; 95% confidence interval 0.50-0.98; highest tertile vs. inactive group), cycling (RR = 0.73; 0.54-0.99) in females and non-occupational vigorous physical activity. For occupational physical activity, lung cancer risk was increased for unemployed men (adjusted RR = 1.57; 1.20-2.05) and men with standing occupations (RR = 1.35; 1.02-1.79) compared with sitting professions. There was no evidence of heterogeneity of physical activity associations across countries, or across any of the considered cofactors. For some histologic subtypes suggestive sex-specific reductions, limited by subgroup sizes, were observed, especially with vigorous physical activity. In total, our study shows no consistent protective associations of physical activity with lung cancer risk. It can be assumed that the elevated risks found for occupational physical activity are not produced mechanistically by physical activity itself but rather reflect exposure to occupation-related lung cancer risk factors.  相似文献   
788.
We report a case of cutis verticis gyrate-mental deficiency syndrome (CVG-MD) which was associated with drug-resistant epilepsy and bilateral occipital polymicrogyria. Genetic analysis showed an increased number of breaks at the 3p14 and 16q23 sites. We hypothesize that a deleterious factor acting at a critical period of intrauterine development could result in the cerebral malformation and in the development of CVG. Neuroradiological investigation is warranted in cases of CVG-MD.  相似文献   
789.
Due to poor willingness in the population to donate organs and increasing number of patients on the waiting list for organ transplantation there is an imminent need on cadaveric organs. Although efforts have been to optimize the prerequisites for organ donation, less than 50% of possible organ harvesting procedures take place. In our country, only 13.1 organ donations .per 1 million inhabitants were realized in 2001. These data force the medical community to maximize the utility of the donor pool. A refined surgical technique, increased efficacy of solutions for graft conservation, an advanced perioperative management and new potent immunosuppressive drugs contributed to a post-transplant 1-year graft and patient survival of up to 80 to 90%. The quality of a graft has a significant impact on the outcome of transplantation. An optimal graft function will not only be achieved with an adequate surgical and preservation technique but also with an appropriate management of the brain-dead donor on the intensive care unit. Basic knowledge of brain death definition, insight into the organization of organ donation, management of the donor, and modern surgical harvesting techniques are presented.  相似文献   
790.
Recently, single blood level measurement 2 hours after cyclosporine administration (C2) is taken as a more sensitive indicator of drug exposure in de novo transplant recipients than trough levels (C0). However, few studies focused on the determination of the C2 target range maximum and its associated adverse events in stable liver recipients. This prospective study was designed to assess the relative risk of developing CsA related side effects in patients with high C2-levels. Adverse effects were determined clinically, and by using a specially designed questionnaire. Eventual adverse events as well as C2 levels were determined repeatedly up to 4 times in 3-months intervals (observation period 9 +/- 3 months) in 36 long-term liver recipients (1-13.5 years post-transplant), in addition to conventional C0 levels. Cyclosporine dose was adjusted according to a predefined C0 target level range and clinical status. Totally 103 questionnaires and the corresponding paired CsA blood level records were obtained. C0 levels and C2 levels ranged from 90 to 287 (143 +/- 31) ng/ml and from 212 to 1358 (672 +/- 203) ng/ml respectively. No patient experienced a rejection episode during the observation period, demonstrating the efficiency of the immunosuppressive therapy. However, 33/36 patients (91%) showed symptoms attributable to CsA therapy. C2 levels above 750 ng/ml, determined at least twice in an interval of 3 months, were identified as a relevant risk factor for the presence of multiple adverse effects, which were defined as the combination of hypertension, renal insufficiency and more than two neurological complaints (RR = 3.11, p<0.01). This risk population was not completely identified by determination of C0 level.  相似文献   
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