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Aniline and its halogenated derivatives are widely used as chemical intermediates. The purpose of this study was to determine the hepatotoxic and nephrotoxic potential of the 2-haloanilines. Male Fischer 344 rats (n > or = 4) were injected (i.p.) with 1.0 or 1.25 mmol/kg of: aniline (A), 2-fluoroaniline (2-FA), 2-chloroaniline (2-ClA), 2-bromoaniline (2-BrA), 2-iodoaniline (2-IA) or vehicle (0.9% saline, 2.5 ml/kg). All compounds were injected as hydrochloride salts. Renal and hepatic function was monitored 24 h after treatment. All of the 2-haloanilines induced oliguria, diminished kidney weight, tubular casts and decreased renal cortical slice accumulation of organic anions. Blood urea nitrogen (BUN) levels were increased (P < 0.05) by treatment with 1.0 or 1.25 mmol/kg of 2-FA, 2-ClA or 2-BrA. Hepatic alterations were also observed and characterized by elevated plasma ALT/GPT activity and altered morphology in the centrilobular region. The nephrotoxic and hepatotoxic potentials were similar among the 2-haloanilines but aniline was less toxic than its 2-halo derivatives. These results demonstrated that halogen substitution at the 2-position of aniline increased hepatic and renal toxicity. However, the severity of toxicity was not influenced by the nature of the halogen substituent.  相似文献   
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This study used structural equation modeling to examine the relationships between emotion dysregulation, internalizing symptoms, nonsuicidal self-injury (NSSI), and suicide. One hundred forty-eight undergraduates completed a brief structured interview and self-report measures of emotion dysregulation, internalizing symptoms, and NSSI and suicidal behaviors. Results indicated a significant indirect effect of emotion dysregulation on NSSI via internalizing symptoms and on suicide attempts via NSSI. Findings provide a more nuanced understanding of the indirect association between emotion dysregulation and NSSI and suicidal behaviors. Implications for the potential utility of targeting internalizing symptoms as well as emotion dysregulation in interventions addressing NSSI and suicidal behaviors are discussed.  相似文献   
4.
Given that suicide is a leading cause of death worldwide, there has been considerable research on theories of suicide risk. Despite the volume of such research, each theory is largely investigated in isolation and there has been little attempt to integrate them. Thus, the goal of the present study is to integrate two theories of suicide risk, Alloy and Abramson’s hopelessness theory of suicide (HT) and Joiner’s interpersonal psychological theory of suicide (IPTS), into one mediational model where the effects of the risk associated with the HT variables (i.e., a negative cognitive style) on suicidal ideation are transmitted by the IPTS (i.e., perceived burdensomeness and thwarted belonging) variables. Participants were 245 young adults with elevated levels of depressive symptoms who completed self-report measures of suicide risk at baseline and a measure of suicidal ideation eight weeks later. The results of a mediated model supported our hypothesis. The effects of the HT variables on suicidal ideation were mediated by the IPTS variables. Furthermore, results did not support the reverse model, suggesting specificity of the direction of our hypotheses. These findings imply that there may be merit in attempting to integrate theories of suicide risk rather than studying them in isolation.  相似文献   
5.
Introduction: Various anomalies in the development of the great thoracic veins of the embryo can be incidentally discovered in the normal adult. Duplication of superior vena cava (SVC) is a rare abnormality, but the most common thoracic venous congenital anomaly.

Case reports-methods: We present two cases in the intensive care unit of our hospital, of asymptomatic patients who underwent an uneventful central line placement in the left subclavian vein. The track of the catheter, as shown in the X-ray, was misplaced to the left of the aorta and further investigation with computed tomography angiography confirmed a persistent left SVC. In both cases the vein drained into the coronary sinus and then to the right atrium. In the second case the echocardiography revealed a dilated coronary sinus.

Conclusions: Double SVC can be fortuitously discovered during catheter insertion, thoracic or cardiac imaging and surgery. In most cases it drains into the right atrium, through the coronary sinus. This entity is significant to the physician because of its importance in differential diagnosis as a cause of a widened mediastinum, as well as any difficulty that can occur in the placement of a central venous catheter or a pace maker.  相似文献   
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Cognitive Therapy and Research - Reducing access to highly lethal methods for suicide (i.e., means safety) has been promoted as a way to reduce suicide risk. Research by Anestis et al. (J Affect...  相似文献   
8.
Myocardial metabolic rate and coronary flow are closely related limiting thus the diagnostic value of coronary sinus saturation monitoring as an indicator of flow. Regional venoarterial CO2 gradient was found elevated during low flow in various clinical and experimental conditions, in animals and humans. This study was undertaken to examine the impact of the variations of cardiac mechanical work on veno-arterial CO2 content and partial pressure difference (deltaPCO2) of the coronary sinus blood. Twenty-seven patients of either sex (m/f = 21/6), undergoing coronary artery bypass grafting under extracorporeal circulation, were studied. Monitoring included a Swan-Ganz catheter and a coronary sinus line. The correct position of the late was verified by the waveform displayed in the monitor. Immediately after cannulae placement, a hemodynamic profile was obtained and simultaneous arterial and coronary sinus sampling for blood gas analysis was done in an ABL 720 (Radiometer Copenhagen) analyzer. A second collection of the same data was obtained five minutes later with the patients in a slight "head-down" position. Conditions for exclusion was intersample variation of hemoglobin's concentration greater than 15% and sodium ion concentration difference greater than 10% of the greater value. Arteriovenous oxygen partial pressure difference (deltaP(a-cs)O2), veno-arterial carbon dioxide partial pressure difference (deltaP(cs-a)CO2), O2 & CO2 content difference and heart's respiratory quotient were calculated and correlated to cardiac output (CO) and the other hemodynamic parameters. Statistical analysis employed t-paired test and linear regression. No ischemia was detected during sampling. "Head-down" position had a significant impact to all hemodynamic parameters except heart rate. In both data rows, although CO ranged widely and altered significantly, coronary sinus oxygen saturation and arteriovenous O2 content difference were stable and showed insignificant correlations to all the hemodynamic parameters that were studied. Carbon dioxide content difference (coronary sinus-arterial) showed a trending of decrease with higher flow. DeltaP(cs-a)CO2 appeared stable and independent of flow. Finally, respiratory quotient decreased significantly from 0.91 +/- 0.4 to 0.86 +/- 0.4 (mean +/- SD; p < 0.05). The heart's high basal oxygen consumption and the almost near hemoglobin's desaturation transcoronary extraction of oxygen limits the value of coronary sinus saturation monitoring as indicator of coronary flow. Heart's little extraction reserve is faced with coronary flow reserve. In the physiologic range and under the conditions of anesthesia, elevated CO2 production is accompanied with increased coronary flow. Under these circumstances, deltaP(cs-a)CO2 appears stable and is not suitable for clinical decisions concerning heart's coronary flow.  相似文献   
9.
Ecological momentary assessment (EMA) is a group of research methods that collect data frequently, in many contexts, and in real-world settings. EMA has been fairly neglected in suicidology. The current article provides an overview of EMA for suicidologists including definitions, data collection considerations, and different sampling strategies. Next, the benefits of EMA in suicidology (i.e., reduced recall bias, accurate tracking of fluctuating variables, testing assumptions of theories, use in interventions), participant safety considerations, and examples of published research that investigate self-directed violence variables using EMA are discussed. The article concludes with a summary and suggested directions for EMA research in suicidology with the particular aim to spur the increased use of this methodology among suicidologists.  相似文献   
10.
The agricultural fungicide N-(3,5-dichlorophenyl)succinimide (NDPS) induces nephrotoxicity in mammals characterized as polyuric renal failure and proximal tubular necrosis. Recent studies have suggested that NDPS-induced nephrotoxicity may be mediated by metabolites arising from the nephrotoxic NDPS metabolites N-(3,5-dichlorophenyl)-2-hydroxysuccinimide (NDHS) and/or N-(3,5-dichlorophenyl)-2-succinamic acid (2-NDHSA). The purpose of this study was to examine the effects of N-acetylcysteine (NAC), a nucleophilic agent, and two nonnucleophilic N-acetylamino acids, N-acetylserine (NAS) and N-acetylalanine (NAA), on NDPS and NDPS metabolite-induced nephrotoxicity. Male Fischer 344 rats (4-8/group) were administered intraperitoneally (ip) an N-acetylamino acid (1 mmol/kg) 2 h before an ip injection of NDPS (0.4 mmol/kg), NDHS (0.1 mmol/kg), 2-NDHSA (0.1 mmol/kg), or vehicle. Renal function was then monitored at 24 and 48 h. NAC pretreatment markedly attenuated NDPS-, NDHS-, and 2-NDHSA-mediated nephrotoxicity. The nonnucleophilic N-acetylamino acids (NAS, NAA) only partly reduced NDPS and NDHS nephrotoxicity, and they had little effect on 2-NDHSA nephrotoxicity. These results suggest that reactive NDPS metabolites may be formed from NDHS and 2-NDHSA and that nucleophilic substrates (e.g., NAC) may offer protection from NDPS-induced nephrotoxicity. However, mechanisms other than chemical neutralization of reactive NDPS metabolites may also be contributing to the attenuation of NDPS nephrotoxicity, since nonnucleophilic N-acetylamino acids (e.g., NAA) also provided some protection against NDPS and NDHS nephrotoxicity.  相似文献   
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