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排序方式: 共有1234条查询结果,搜索用时 15 毫秒
1.
Emilia Lachica Aurelio Luna Enrique Villanueva 《International journal of legal medicine》1989,103(2):111-119
Summary The diagnosis of myocardial infarction requires the use of a group of tests that are very efficient, quick and inexpensive. Another important consideration is the choice of myocardial sampling zones, especially in cases of differential diagnosis between a cardiac injury secondary to a trauma or violent asphyxia and others, secondary to myocardial infarction. The aim of this work was to choose, through discriminant analysis, the most useful zones of cardiac tissue for the quantification of free fatty acids and free carnitine and for the performance of the K/Na quotient, as biochemical parameters for the postmortem diagnosis of myocardial infarction. According to the discriminant analysis performed, seven zones of cardiac tissue are necessary to achieve a differential diagnosis among myocardial infarction, other natural deaths, and violent deaths with a 71.9% efficacy. Greater diagnostic efficacy was found (78.1%) for differentiating between natural deaths and violent deaths.
Offprint requests to: E. Lachica 相似文献
2.
Brighina F Piazza A Daniele O Fierro B 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,145(2):177-181
Recent studies showed hyperexcitability of the occipital cortex in subjects affected by migraine with aura. It has been shown that 1 Hz repetitive transcranial magnetic stimulation (rTMS) reduces excitability of visual cortex in normal subjects. The aim of the study was to investigate the effects of low frequency (1 Hz) rTMS on visual cortical excitability by measuring changes in phosphene threshold (PT) in subjects with migraine with aura. Thirteen patients with migraine with aura and 15 healthy controls were examined. Using a standardized transcranial magnetic stimulation protocol of the occipital cortex, we assessed the PT (the lowest magnetic stimulation intensity at which subjects just perceived phosphenes) before and after a 1-Hz rTMS train delivered at PT intensity for 15 min. The difference in the proportion of subjects reporting phosphenes in migrainer and control groups was significant (migrainers: 100% vs controls 47%; P<0.05), and 1 Hz rTMS over the occipital cortex led to a significantly increased visual cortex excitability expressed as a decrease in PT in subjects affected by migraine with aura. Conversely, after a 1-Hz TMS train normal subjects showed increased PT values, which suggests a decreased visual cortex excitability. Our findings confirm that the visual cortex is hyperexcitable in migrainers and suggest a failure of inhibitory circuits, which are unable to be upregulated by low frequency rTMS. 相似文献
3.
Bellido I Gomez-Luque A Plaza A Rius F Ortiz P Sanchez de la Cuesta F 《Neuroscience letters》2002,321(1-2):110-114
S-adenosyl-L-methionine (SAM) has shown efficacy in speeding the onset of the antidepressant effect of imipramine in depressed patients. This effect may be related to their interactions at the serotonin(1A) (5-HT(1A)) receptors. Acute imipramine up-regulated the frontal cortex 5-HT(1A) receptors (B(max), 51.5 +/- 8.4 fmol/mg protein) vs. saline (B(max), 27.5 +/- 5.9 fmol/mg protein), and did not show antidepressant effect. Acute SAM and imipramine+SAM did not modify frontal cortex 5-HT(1A) receptors, and showed antidepressant effects (decrease of the immobility response of 26%, P<0.01; and 47%, P<0.001) vs. saline. All the chronic treatments showed antidepressant effects and up-regulated the hippocampus 5-HT(1A) receptors. SAM prevents the 5-HT(1A) receptor up-regulation induced by acute imipramine in the frontal cortex. This mechanism may contribute to imipramine's antidepressant effect. 相似文献
4.
Modelling asthma epidemics on the relationship between air pollution and asthma emergency visits in Barcelona, Spain 总被引:1,自引:0,他引:1
We have investigated different methods of controlling for asthma epidemics in the time series regression of the relationship between air pollution and asthma emergency visits in Barcelona, Spain. The relationship between air pollution and asthma emergency room visits was modelled using autoregressive Poisson models. We examined the effect of using no control by epidemics, and modelling asthma epidemics with a single dummy variable, six dummy variables, and a dummy variable for each epidemic day. Air pollution coefficients increased when controlling asthma epidemics with six dummy variables instead of a single variable. They further increased when autocorrelation was allowed for. Standard errors were relatively unaffected when either the epidemics or the autocorrelation were included in the model. Black smoke, nitrogen dioxide and ozone were statistically significant associated to asthma emergency visits after using six dummy variables to control for asthma epidemics. We have shown that different models, including different confounding variables, give markedly different estimates of the effect of a pollutant on health. Care is needed in the interpretation of such models, and careful reporting so it is clear how the confounding variables have been modelled. 相似文献
5.
de Oliveira MA de Leon AC Freire EC de Oliveira HC 《Acta obstetricia et gynecologica Scandinavica》2007,86(1):73-80
OBJECTIVE: To identify risk factors that are associated with the development of scar endometriosis after obstetric hysterotomies. The hypothesis is that early hysterotomy in pregnancy (before 22nd week) is the main risk factor for the development of scar endometriosis. METHODS: The authors conducted a case-control study between April 2000 and June 2003. A total of 117 women were selected, including 39 cases and 78 controls. Exposure and confounding variables were measured by a standardized questionnaire, which included sociodemographic characteristics, reproductive/physiologic history, past pathological history, history of obstetric surgeries, family history, and social history. The odds ratio (OR) and its 95% confidence interval (CI) were calculated using bivariate analysis for each possible risk factor. These estimates were obtained by multivariate analysis using unconditional logistic regression. Tests were made to assess the fit of the final model. RESULTS: In the multivariate analysis, positive associations were observed between scar endometriosis and hysterotomy type (early versus late: OR = 42.99; CI 8.77-210.81), amount of the menstrual blood flow (heavy versus light/normal: OR = 11.97; CI 2.35-60.82), and alcoholic consumption (yes versus no: OR = 5.31; CI 1.22-23.11). Negative association was observed between scar endometriosis and parity (OR = 0.61; CI 0.31-1.23), however it was not statistically significant (p>0.05). CONCLUSIONS: Early hysterotomy in pregnancy is the main risk factor for scar endometriosis. Increased menstrual flow and alcohol consumption are also risk factors, while high parity may be a protecting factor. 相似文献
6.
Lucia Bernasconi Benedetta Brolli Aurelio Negro Jorge L Zoino Azzurra Schicchi Valeria M Petrolini Davide Lonati Anna Ronchi Carlo A Locatelli 《La Medicina del lavoro》2022,113(2)
Introduction:Most of the molybdenum (Mo) is used in metallurgical applications, the tetrathiomolybdate form is an experimental chelating agent for Wilson’s disease. Human data of acute Mo exposure are lacking and, no report of no-observed-adverse-effect level (NOAEL) has been described until now.Case study:We report a case of acute occupational exposure to molybdenum, with the related plasma and urine molybdenum concentrations, caused by an accidental ingestion of a sip of an anti-corrosion liquid for metal containing sodium molybdate. Our purpose was to evaluate potential systemic toxicity of molybdenum and to evaluate the dose-response/dose-effect relationship. We estimated the amount of ingested molybdenum to make a mg/kg relationship and performed repeated urine and plasma molybdenum determinations. The patient was hospitalized for three days to monitor possible development of acute symptoms/biochemical alterations.Discussion:We estimated the amount of the sip around 50 ml, with an estimation of a total of 5 gr of sodium molybdate that, for the patient bodyweight of 80 kg, would mean 62,5 mg/kg of ingested Mo. Blood and urine samples collected 2 hours after ingestion showed 50 mcg/L (reference range: 0.43 – 1.8 mcg/L) and 630 mcg/L (refence range: up to 116 mcg/L) of Mo respectively, confirming acute exposure. The patients remained asymptomatic confirming that an estimated oral dose of Mo of 62.5 mg/kg was not associated with adverse effects.Conclusions:Our value, being extrapolated by a single case, will require further confirmations from other studies to allow a full evaluation of a NOAEL. Nevertheless, it does not preclude its use in evaluating the probable absence of adverse effect in the context of acute Mo exposure. 相似文献
7.
Kevin E. Bennet Kendall H. Lee James N. Kruchowski Su-Youne Chang Michael P. Marsh Alexander A. Van Orsow Aurelio Paez Felicia S. Manciu 《Materials》2013,6(12):5726-5741
Building on diamond characteristics such as hardness, chemical inertness and low electron emission threshold voltage, the current microscopic, spectroscopic and voltammetric investigations are directed towards improving the properties of electrode coating materials for their future use in clinical studies of deep brain stimulation via fast-scan cyclic voltammetry (FSCV). In this study we combine the capabilities of confocal Raman mapping in providing detailed and accurate analysis of local distributions of material constituents in a series of boron-doped polycrystalline diamond films grown by chemical vapor deposition, with information from the more conventional techniques of scanning electron microscopy (SEM) and infrared absorption spectroscopy. Although SEM images show a uniform distribution of film crystallites, they have the limitation of being unable to differentiate the distribution of boron in the diamond. Values of 1018–1021 atoms/cm3 of boron content have been estimated from the absorption coefficient of the 1290 cm−1 infrared absorption band and from the 500 cm−1 Raman vibration. The observed accumulation of boron atoms and carbon sp2 impurities at the grain boundaries suggests that very high doping levels do not necessarily contribute to improvement of the material’s conductivity, corroborating with voltammetric data. FSCV results also indicate an enhanced stability of analyte detection. 相似文献
8.
Aracely Angulo-Molina Julio Reyes-Leyva Aurelio López-Malo Jesús Hernández 《Nutrition and cancer》2013,65(2):167-176
In recent years, efforts to improve cancer therapy have focused on developing new anticancer agents, such as mitocans. These agents include vitamin E analogues and suppress cancer by inducing apoptosis by targeting mitochondria. Alpha tocopheryl succinate (α-TOS) is the most effective form of vitamin E analogues causing inhibition of proliferation and apoptosis of cancer cells. Both in vitro and in vivo studies have demonstrated that α-TOS selectively kills tumor cells with little or no effect on normal cells. Treatment with α-TOS shows great promise for future clinical applications, as it causes cell death, at least in part, by selectively inducing apoptosis by mitochondrial destabilization. This review presents an overview of perspectives on α-TOS and the potential uses of α-TOS in cancer treatment and other clinical applications. 相似文献
9.
Passarello C Giambona A Prossomariti L Ammirabile M Pucci P Renda D Pagano L Maggio A 《British journal of haematology》2008,143(1):138-142
This study describes a new molecular condition in the alpha(2)-globin gene (HBA2) found in six unrelated families from Southern Italy (Campania and Sicily). This new double mutant form of haemoglobin is called Hb Southern Italy and originated from the coexistence of two known mutations occurring in the same globin gene, HBA2 26 G-->A (Hb Caserta) and HBA2 130 G-->C (Hb Sun Prairie). Hb Sun Prairie was originally observed in Indian patients in either the homozygous state, with severe hemolytic anemia, and in the heterozygous state with microcytosis, or in asymptomatic cases as an alpha-thalassemia carrier phenotype. Hb Caserta was observed for the first time in a Casertian family (South Italy) that displayed a slowmigrating haemoglobin upon investigation. We report the clinical phenotype and molecular study of this new double mutant form of haemoglobin in heterozygous and homozygous subjects, as well as in association with alpha degrees delectional thalassemia. 相似文献