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101.
102.
Background: Phosphatidylcholine, a lecithin extracted from soybeans can reduce serum cholesterol to some extent. Intravenous use may prevent fat embolism in polytrauma patients. When injected intralesionally in a formulation containing also deoxycholate and ethanol it is supposed to act as “fat burner” to reduce undesired fat deposits; there is little evidence‐based scientific support for this indictaion. Objective: To evaluate the capability of phosphatidylcholin + deoxycholate + ethanol (PPC/DC/E) to reduce body fat with a half‐side pilot study for the reduction of saddlebag trochanteric bulges. Methods: PPC/DC/E was injected into the right posterior trochanteric areas three times at weeks 0, 3 and 6. Treatment areas and the same regions of the contralateral side as a control were evaluated by sonography. Tape measurements were taken and the thickness of the subcutaneous adipose tissue (SAT) was measured with an optical device (Lipometer®) at baseline and at week 8 and week 20 (2 and 14 weeks after completign therapy). Results: In this half‐side trial, no significant reduction of subcutaneous fat was achieved after three treatments with PPC/DC/E when compared to the untreated side.Transient inflammatory reactions occurred in all patients. Limitations: Only the commercially available formulation containing the three components was tested. Conclusion: The off‐label use of PPC/DC/E as a “fat burner” did not produce measurable reduction of undesired trochanteric fat deposits.  相似文献   
103.
One of the more dramatic changes in the healthcare industry has been the movement of physicians, particularly younger professionals, from private practice to some type of healthcare organization. In this study we examine the importance attached to specific incentives by physicians in making an affiliation decision and healthcare administrators. Our results suggest significant differences between the importance placed on certain recruiting incentives by physicians and healthcare administrators. Further, they suggest distinct differences in importance ratings by different types of physicians. Implications of this study argue for developing different compensation packages to appeal to different segments of physicians.  相似文献   
104.
Functional lipoprotein lipase activity was recently described in rat brain. The present study was performed to further characterize the biologic significance of brain lipoprotein lipase (heparin releasable component) and elucidate regulatory factors. Comparative studies were performed on tissue (brain, adipose, and heart) heparin releasable lipoprotein lipase in the fasted and diabetic (streptozotocin 100 mg/kg BW IP) rat. Both fasting (96 hours) and diabetes (ten days) significantly decreased brain (cortical) (P less than .05) and adipose (epididymal fat pad) (P less than .001) lipoprotein lipase activity. In contrast, heart muscle enzyme activity was significantly increased (P less than .001) in response to fasting and diabetes. Refeeding (Purina chow 96 hours) and insulin replacement (96 hours) reversed these changes in tissue lipoprotein lipase consequent to fasting and diabetes, respectively. There was a positive correlation between the changes in serum insulin concentration and adipose lipoprotein lipase, but there was no correlation between this parameter and brain or heart lipoprotein lipase. In addition, although T3 therapy normalized the low T3 state associated with both fasting and diabetes, it had no effect on the enzyme activity in the studied tissues. However, subsequent studies demonstrated that hypothyroidism (2 weeks post thyroidectomy) significantly decreased brain lipoprotein lipase activity (P less than .001) and increased both the adipose (P less than .025) and heart (P less than .025) enzyme activity. T3 replacement (0.8 micrograms/100 BW/d for 1 week) reversed the effects of hypothyroidism. However, the relationship between brain enzyme activity and serum T3 was nonlinear as hyperthyroidism tended to reduce brain LPL activity.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
105.
Heterotopic ossification can occur in neurologic disorders, burns, musculoskeletal trauma, and metabolic disorders. In addition to producing the complications of contracture, skin breakdown, and pain, it can cause peripheral nerve entrapment. Nerve entrapment due to heterotopic ossification may be misdiagnosed, and it is difficult to evaluate and treat without recurrence. Computed tomography is especially useful in localization before surgical release of the entrapped nerve. Resection of heterotopic ossification can be successful using disodium etidronate to decrease the risk of recurrence, and resection can improve range of motion and nerve function. Two case studies of nerve entrapment due to heterotopic ossification are presented with the results of computed tomography localization, successful resection, and long-term follow-up. Clinicians should be aware of this complication and the potential for rapid nerve injury. If heterotopic ossification is causing clinically significant peripheral nerve entrapment, early surgical treatment may be indicated, and may be successful.  相似文献   
106.
Alterations in the balance of functional activity within the serotonin [5-hydroxytryptamine (5-HT)] system are hypothesized to underlie impulse control. Cocaine-dependent subjects consistently show greater impulsivity relative to nondrug using control subjects. Preclinical studies suggest that the 5-HT(2A) receptor (5-HT(2A)R) contributes to the regulation of impulsive behavior and also mediates some of the behavioral effects of cocaine. We hypothesized that the selective 5-HT(2A)R antagonist M100907 would reduce inherent levels of impulsivity and attenuate impulsive responding induced by cocaine in two animal models of impulsivity, the differential reinforcement of low rate (DRL) task and the one-choice serial reaction time (1-CSRT) task. M100907 reduced rates of responding in the DRL task and premature responding in the 1-CSRT task. Conversely, cocaine disrupted rates of responding in the DRL task and increased premature responding in the 1-CSRT task. M100907 attenuated cocaine-induced increases in specific markers of behavioral disinhibition in the DRL and 1-CSRT tasks. These results suggest that the 5-HT(2A)R regulates inherent impulsivity, and that blockade of the 5-HT(2A)R alleviates specific aspects of elevated levels of impulsivity induced by cocaine exposure. These data point to the 5-HT(2A)R as an important regulatory substrate in impulse control.  相似文献   
107.
The chemical composition of cigarette mainstream smoke (MS) has been quantitatively analyzed in multiple studies, often with the objective to toxicologically evaluate and compare various types of MS. Increases and decreases in yields of constituents between MS types can only be consolidated if these yields are compared on the basis of toxicological properties of the individual constituents. For the risk assessment of various complex mixtures including MS, a hazard index (HI) approach has been used that requires weighing of the exposure to individual MS constituents by cancer and noncancer potency values. The objective of the current study is to review the past uses of the HI concept for MS and smokeless tobacco and discuss strengths and limitations of using this concept. Published information as well as information made available on the Web was used. The HI concept has been applied to MS for determining and comparing theoretical lifetime risks, for consumer communication, for the prioritization of constituents for reduction, for ingredient assessment, and for the selection of constituents for regulation. The limitations of this approach are associated with the limited number of MS constituents with available yield data, the gaps and uncertainties in available potency values, the application to relatively high exposure concentrations, and the default assumption of additivity. The derived theoretical noncancer index is dominated by acrolein to an extent that there seems to be not much advantage in using the HI concept for noncancer assessments. The derived theoretical cancer index is dominated by genotoxic carcinogens of the MS vapor phase and may thus complement currently used toxicological assays in a tiered evaluation approach. As is the case for every other assay and interpretation model, the HI concept needs to be applied with its limitations and weaknesses in mind. Its best application is for comparative purposes. It should be kept in mind that the HI concept is a theoretical concept and does not provide actual risk information.  相似文献   
108.
Anticonvulsants, notably those which modulate GABA activity, have shown efficacy in reducing aggressive behavior. Previously, we found dose-related decreases in human aggressive responding following acute tiagabine administration. Here, we examined the effects of chronic tiagabine over a 5-week period. Twelve individuals at increased risk for aggressive and violent behavior (currently on parole/probation with personality and/or substance use disorders) were randomly assigned to placebo (n?=?6) or an escalating dose sequence of placebo, 4?mg, 8?mg, 12?mg, placebo (n?=?6). Data were analyzed using both frequentist and Bayesian mixed models, evaluating aggressive behavior as a function of time, dose condition, and their interaction. For aggressive responding, there was a significant interaction of drug condition and time. Aggression in the tiagabine condition decreased for each additional week in the study, while participants in the placebo condition failed to demonstrate similar change over time. For monetary-reinforced responding, no drug or drug by time interactions were observed, suggesting specificity of drug effects on aggression. The small number of subjects limits the generality of the findings, and previous studies with tiagabine are limited to acute dosing and case report investigations. However, the present data provide an indication that tiagabine merits further examination as an agent for management of impulsive aggression.  相似文献   
109.
Congenital dyserythropoietic anaemias (CDAs) are heterogeneous, hereditary disorders hallmarked by ineffective erythropoiesis and tissue iron overload. Growth differentiation factor 15 (GDF15) was suggested to mediate iron overload in iron-loading anaemias, such as the thalassaemias and CDAI by suppressing hepcidin, the key regulator of iron absorption. Here, we show that serum GDF15 concentrations are elevated in subjects with CDAI and CDAII. Despite similar disease characteristics, CDAI patients present with significantly higher GDF15 concentrations compared to CDAII patients. Hepcidin concentrations are inappropriately low in CDAII patients considering the severe hepatic iron overload associated with this disorder. GDF15 significantly correlates with the degree of anaemia (Hb), the response of erythropoiesis (reticulocyte index) as well as with iron availability in the serum (transferrin saturation). The observation that GDF15 is elevated in CDAII patients is consistent with the proposal that GDF15 is among the erythroid factors down-regulating hepcidin and contributing to iron overload in conditions of dyserythropoiesis.  相似文献   
110.
PURPOSE: West syndrome is a severe epileptic encephalopathy of infancy characterized by a poor developmental outcome and hypsarrhythmia. The pathogenesis of hypsarrhythmia is insufficiently understood. METHODS: We investigated eight patients with infantile spasms and hypsarrhythmia (group I) and 8 children with complex partial seizures (group II) using simultaneous recordings of electroencephalogram (EEG) and functional MRI. Hemodynamic responses to epileptiform discharges and slow wave activity (EEG delta power) were analyzed separately. RESULTS: In group I (mean age, 7.82 +/- 2.87 months), interictal spikes within the hypsarrhythmia were associated with positive blood oxygenation level-dependent (BOLD) changes in the cerebral cortex (especially occipital areas). This was comparable with cortical positive BOLD responses in group II (mean age, 20.75 +/- 12.52 months). Slow wave activity in group I correlated significantly with BOLD signal in voxels, which were localized in brainstem, thalamus, as well as different cortical areas. There was no association between BOLD effect and EEG delta power in group II. Moreover, as revealed by group analysis, group I differed from group II according to correlations between BOLD signal and slow wave activity in putamen and brainstem. CONCLUSIONS: This study demonstrates that multifocal interictal spikes and high-amplitude slow wave activity within the hypsarrhythmia are associated with the activation of different neuronal networks. Although spikes caused a cortical activation pattern similar to that in focal epilepsies, slow wave activity produced a hypsarrhythmia-specific activation in cortex and subcortical structures such as brainstem, thalamus, and putamen.  相似文献   
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