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971.
972.
Introduction Temperature regulation in humans is controlled by the hypothalamus. After death by neurological criteria, the hypothalamus
ceases to function and poikilothermia ensues. Preservation of normothermia in those patients destined to become organ donors
is an important part of maintaining the normal physiology of the organs and organ systems. Typical means of achieving normothermia
include increasing the temperature of the ambient air, infrared warming lights, instillation of warmed intravenous fluids,
and warm air or water blankets.
Methods In this prospective case series of five organ donors, we used an intravascular temperature modulation catheter (Alsius, Irvine,
CA) to maintain normothermia in organ donors declared dead by neurological criteria. Data on accuracy of temperature maintenance
at 37°C and nursing ease of use were collected.
Results This intravascular temperature modulation catheter provided an accurate method of temperature regulation in brain death donor
and easier to use from a nursing workload perspective.
Conclusions Intravascular warming is a viable method for the maintenance of normothermia in organ donors. The experience here provides
some insight into the ability of these devices to warm patients in other clinical situations.
Originally presented at the Neurocritical Care Society, 2nd Annual Meeting, San Diego, CA, 2004. 相似文献
973.
Maximilian Kotz Leonie Wenz Anders Levermann 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(32)
Changes in mean climatic conditions will affect natural and societal systems profoundly under continued anthropogenic global warming. Changes in the high-frequency variability of temperature exert additional pressures, yet the effect of greenhouse forcing thereon has not been fully assessed or identified in observational data. Here, we show that the intramonthly variability of daily surface temperature changes with distinct global patterns as greenhouse gas concentrations rise. In both reanalyses of historical observations and state-of-the-art projections, variability increases at low to mid latitudes and decreases at northern mid to high latitudes with enhanced greenhouse forcing. These latitudinally polarized daily variability changes are identified from internal climate variability using a recently developed signal-to-noise-maximizing pattern-filtering technique. Analysis of a multimodel ensemble from the Coupled Model Intercomparison Project Phase 6 shows that these changes are attributable to enhanced greenhouse forcing. By the end of the century under a business-as-usual emissions scenario, daily temperature variability would continue to increase by up to a further 100% at low latitudes and decrease by 40% at northern high latitudes. Alternative scenarios demonstrate that these changes would be limited by mitigation of greenhouse gases. Moreover, global changes in daily variability exhibit strong covariation with warming across climate models, suggesting that the equilibrium climate sensitivity will also play a role in determining the extent of future variability changes. This global response of the high-frequency climate system to enhanced greenhouse forcing is likely to have strong and unequal effects on societies, economies, and ecosystems if mitigation and protection measures are not taken.The effect of anthropogenic greenhouse gas emissions on mean climatic conditions is well understood. Theory, observational, and modeling work all demonstrate that average temperatures increase as a result of elevated greenhouse gas concentrations (1). However, it is also of considerable importance to natural and human systems whether changes in the temporal variability of climatic conditions have accompanied historical global warming and whether they will do so in the future (2–5). A more variable climate implies greater uncertainty and greater frequency of extremes, both of which constitute more damaging conditions.The variability of climate from one year to the next has received considerable attention. Large-scale climatic oscillations, such as the El Niño Southern Oscillation and the Indian Ocean Dipole, are dominant determinants of interannual variability (6–8) and have been shown to exhibit more frequent extremes under enhanced greenhouse forcing within comprehensive climate models (9–11), results that are supported by paleoclimatic evidence (12). Identifying a response in interannual temperature variability has been less conclusive. Some studies have attributed recent summer temperature extremes to greater interannual variability, both regionally (13) and globally (14), but there is still debate as to the extent of the role of interannual variability (15–17). Some regional trends in interannual temperature variability have been identified (17–21), but there is no consensus between observations and climate models (22).Here, we focus on variability of temperature at a higher frequency (daily), which a growing body of econometric literature has identified as an important determinant of societal outcomes, including human health (23–27), agriculture (28–30), and economic growth (31). The effect of enhanced greenhouse gas concentrations on the daily variability of temperature is therefore of wide societal importance and a critical component of the impact of anthropogenic climate change.Decreases in daily temperature variability at northern mid to high latitudes have been detected in observations (32–34) and agree well with predictions from comprehensive climate models (34–36) and physical reasoning (34, 35). Previous generations of climate models have also suggested that daily variability may increase during European summer (37) and across the tropics (36, 38), but these predictions have not yet been detected in observations or confirmed in state-of-the art climate models. This paper unifies these works by presenting a global analysis of changes in subseasonal, daily temperature variability under enhanced greenhouse forcing in both reanalyses of historical observations (National Oceanographic and Atmospheric Administration [NOAA] 20th Century Reanalysis Version 3 and the European Centre for Medium-Range Weather Forecasts Reanalysis 5 [ERA-5]) and the latest generation of comprehensive climate models (Coupled Model Intercomparison Project phase 6 [CMIP-6]). Daily temperature variability refers to the intramonthly SD of daily surface temperature from hereon. We consider changes in daily variability in boreal winter (“DJF”), boreal summer (“JJA”), and across the year (“annual”) to both assess the season specific mechanisms identified in previous work and to provide an aggregated overview of variability changes. 相似文献
974.
OBJECTIVE
To assess the magnitude of variability among 11 formulae for human body surface area (BSA) and then among eight for plasma volume (PV), as used to represent physiological indices for body metabolism, drug dosages and body fluid management, and to evaluate the potential cumulative effect of variance inflation with prostate‐specific antigen (PSA) mass as an endpoint.PATIENTS AND METHODS
In 3020 men undergoing robotic radical prostatectomy (RRP) at the Vattikuti Urology Institute between 2001 and 2008, the variation in BSA and PV formulae was calculated, as well as PSA mass, using analysis of variance (anova ), Bland‐Altman plots, linear regression, and correlation analyses.RESULTS
For estimating BSA, anova indicated significant variance among the 11 formulae used (P < 0.001) with a between‐groups variance of 5.45. Bland‐Altman plots reported bias when the Dubois formula was compared to other BSA formulae. Furthermore the anova for PV, with BSA as a predictor, indicated significant variance among the eight formulae used (P < 0.001), with a mean between‐group variance of 444.4 and a mean inflation factor of 81.5. Scatter plots between one PV formula (Boer) and others had a good linear fit. For PSA mass, anova indicated significant variance (P < 0.001) using PV as a predictor, with a mean between‐group variance of 16 799.6 and a mean variance inflation factor of 37.8.CONCLUSIONS
There is significant variation in the BSA calculated by commonly used formulae. This variation is carried over and further magnified in the sequential calculation of PV and PSA mass. Hence arbitrary selection of BSA and PV formulae is likely to affect inferences. 相似文献975.
Study on developmental abnormalities in hypospadiac male rats induced by maternal exposure to di-n-butyl phthalate (DBP) 总被引:3,自引:0,他引:3
The objective of this study was to establish a hypospadiac rat model by maternal exposure to di-n-butyl phthalate (DBP) and to evaluate the developmental abnormalities of hypospadiac male rats. Timed-pregnant rats were given DBP by gastric intubation at doses of 0, 250, 500, 750 or 1000 mg/kg body weight (bw)/day from gestation day (GD) 14 to 18 to establish a hypospadiac rat model. The hypospadias was observed in the 500 and 750 mg/kg bw/day groups, the incidence of which was 6.8 and 41.3%, respectively. Transverse serial histological analysis of genitalia of hypospadiac male rats confirmed the malformation. With exposed dose increasing, the serum testosterone (T) levels of male rats inversely decreased, and in the same dosage group the serum T levels of hypospadiac rats were significantly lower than the levels of nonhypospadiac counterparts. The other reproductive lesions such as cryptorchidism and decreased ratio of anogenital distance/body weight (AGD/bw) were also observed. Autopsy analysis revealed the development of reproductive organs (prostate, testes, epididymis, pituitary gland) and nonreproductive organs (adrenal gland, liver, kidney, heart, spleen) of hypospadiac rats and nonhypospadiac counterparts. The results indicated that the reproductive system and developmental condition of hypospadiac male offspring were damaged severely by DBP. 相似文献
976.
977.
Salo R Leamon MH Natsuaki Y Moore C Waters C Nordahl TE 《Progress in neuro-psychopharmacology & biological psychiatry》2008,32(1):217-223
Long-term methamphetamine (MA) abuse is associated with a wide range of deficits on explicit tasks of selective attention. Less is known however about the effects of MA abuse on implicit measures of attention. Accordingly, we used a computerized spatial priming task to assess implicit attentional processes in 54 MA dependent subjects (mean age=37.04+/-8.9 years) and 32 healthy controls without history of any form of substance abuse (mean age=33.63+/-7.05 years). The MA dependent subjects had been drug-abstinent a minimum of 3 weeks with a mean duration of MA use of 13.27+/-7.75 years. The MA dependent subjects did not differ significantly from controls on either inhibitory priming [p=.37] or facilitory priming) [p=.69]. This result comports with our earlier findings of intact object-based priming in MA dependent individuals and suggests that intact priming effects extend across spatial domains. Further, this pattern of sparing suggests that cortical brain systems typically supporting implicit attentional functioning are relatively intact in long-term MA dependent individuals whereas brain systems supporting explicit attentional processes are affected. 相似文献
978.
Lee BC Yang JW Lee SH Kim SH Joe SH Jung IK Choi IG Ham BJ 《Progress in neuro-psychopharmacology & biological psychiatry》2008,32(1):238-242
The personality traits associated with the noradrenergic system have not yet been clearly established. In the present study, we investigated the variable number of tandem repeats (VNTR) polymorphism of the norepinephrine transporter (NET) and monoamine oxidase A (MAOA), which are major components of the adrenergic system, to elucidate their relationship with personality. A total of 245 normal female Koreans (age 23.05+/-3.07 years, mean+/-SD) volunteered to take part in this study. They filled out a Korean version of the Temperament and Character Inventory (TCI) and were genotyped for the NET and MAOA-VNTR; the NET T-182C and MAOA-uVNTR polymorphisms were checked. We found significant main effect of NET genotype on novelty seeking (NS) score (F=5.43, p=0.021) and significant interaction between the NET and MAOA-uVNTR polymorphisms on NS score (F=11.06, p=0.001). However, there were no relationship between MAOA-uVNTR polymorphisms and NS score, and no association with other temperamental dimensions and these two polymorphisms. Our findings suggest that this functional polymorphism in the noradrenergic gene is associated with novelty seeking in Korean females. 相似文献
979.
Platelet serotonin concentration and suicidal behavior in combat related posttraumatic stress disorder 总被引:1,自引:0,他引:1
Kovacic Z Henigsberg N Pivac N Nedic G Borovecki A 《Progress in neuro-psychopharmacology & biological psychiatry》2008,32(2):544-551
Posttraumatic stress disorder (PTSD) is a serious and global problem, a psychiatric disorder that frequently occurs with different comorbidities, and is associated with a high suicide rate. Pathophysiologically, both PTSD and suicidal behavior are related to disturbances in the central serotonergic system. Serotonin (5-hydroxytryptamine, 5-HT) controls emotional behavior, anxiety, impulsivity and aggression, and nearly all known antidepressants and antianxiety drugs affect 5-HT transmission. Platelet 5-HT can be used as a limited peripheral marker of the central serotonergic synaptosomes, since it is related to particular basic psychopathological characteristics of several psychiatric disorders. Platelet 5-HT concentration has been reported to be similar in PTSD subjects and healthy controls, but suicidal patients across different psychiatric diagnoses have reduced platelet 5-HT concentration. This study examined platelet 5-HT concentration by the spectrofluorimetric method in male subjects: 73 suicidal and 47 non-suicidal veterans with current and chronic combat related PTSD, 45 suicidal and 30 non-suicidal comparative non-PTSD subjects and 147 healthy men. The presence of suicidal behavior (score=0, non-suicidal; scores > or =1, suicidal) was assessed with the Hamilton Depression Rating Scale-17 (HDRS). Platelet 5-HT concentration was significantly lower in suicidal PTSD and non-PTSD patients compared to non-suicidal patients or healthy controls. Since the majority of patients scored very low on item 3 of HDRS, no significant correlation between suicidal scores and platelet 5-HT concentration was found. These results show that reduced platelet 5-HT concentration is related to suicidal behavior in PTSD, and suggest that platelet 5-HT concentration might be used as a peripheral marker to predict suicidal behavior across psychiatric diagnoses. 相似文献
980.
Phencyclidine-induced cognitive deficits in mice are improved by subsequent subchronic administration of the antibiotic drug minocycline 总被引:1,自引:0,他引:1
Fujita Y Ishima T Kunitachi S Hagiwara H Zhang L Iyo M Hashimoto K 《Progress in neuro-psychopharmacology & biological psychiatry》2008,32(2):336-339
BACKGROUND: The N-methyl-d-aspartate (NMDA) receptor antagonist phencyclidine (PCP)-induced cognitive deficits have been used as an animal model for schizophrenia. This study was undertaken to determine whether the antibiotic drug minocycline could improve PCP-induced cognitive deficits in mice. METHODS: Saline (10 ml/kg/day, s.c., once daily on day 1-5, 8-12) or PCP (10 mg/kg/day, s.c., once daily on day 1-5, 8-12) were administered to mice for 10 days. Subsequently, vehicle (10 ml/kg/day, i.p.) or minocycline (4.0 or 40 mg/kg/day, i.p.) was injected for 14 consecutive days. One day after the final injection, a novel object recognition test was performed. RESULTS: PCP-induced cognitive deficits in mice were significantly improved by subsequent subchronic (14 days) administration of minocycline (40 mg/kg), but not minocycline (4.0 mg/kg). CONCLUSIONS: This study suggests that minocycline could be a potential therapeutic drug for cognitive deficits in schizophrenic patients. 相似文献