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391.
Vega Bolívar A 《Radiologia》2011,53(6):531-543
Imaging-guided percutaneous biopsy techniques have been developed to diagnose the lesions detected in breast cancer screening programs based on mammography. Although traditional fine-needle aspiration cytology continues to be indicated in some cases, in many others it has been supplanted by more modern techniques like core biopsy or vacuum-assisted biopsy guided by ultrasonography, stereotaxy, or magnetic resonance imaging. These highly reliable techniques have minimized the need for surgical biopsy. Radiologists play a key role in the histological diagnosis of breast cancer in the early stages of disease and in the evaluation of its local and regional extension through magnetic resonance imaging and sentinel node biopsy.  相似文献   
392.
Dopamine agonists play an important role in the regulation of the central nervous-cardiovascular, renal, and hormonal systems through stimulation of dopaminergic (DA1 and DA2) and alpha- and beta-adrenergic receptors. Several studies have shown that in fat and diabetic mice. The aim of the present study was to evaluate the interaction of the dopaminergic and endocrine systems by determining the effect of the dopaminergic antagonist, metoclopramide, and dopamine on insulin secretion and cardiovascular response by blockade and activation of dopamine receptors in healthy and type 2 diabetic subjects. Healthy subjects (n =15) and subjects with type 2 diabetes (n = 15) of both genders, aged 18 to 60 years, were recruited into this study. A comparative experimental design of 90 minutes was performed in which placebo (0.9% saline) was infused intravenously for the first 30 minutes followed by metoclopramide (7.5 microg/kg/min), a dopamine receptor antagonist for 30 minutes, and then metoclopramide (7.5 microg/kg/min) plus dopamine (0.5-3 microg/kg/min) for 30 minutes. The following clinical and biochemical parameters were measured at the beginning and then every 30 minutes of the experimental period (30', 60' and 90'): systolic-diastolic and mean arterial blood pressure, heart rate, serum glucose, insulin, triacylglycerides, and total cholesterol. Baseline glycosylated hemoglobin was measured and homeostasis model assessment for insulin resistance was calculated from insulin and glucose levels. Twelve-lead electrocardiograms were also obtained at these points. Dopamine infusion induced an increase in serum insulin, systolic blood pressure, and heart rate in healthy subjects but not in subjects with type 2 diabetes. Infusion of metoclopramide induced a hypotensive effect in healthy subjects, which was blunted by inclusion of dopamine in the infusion mixture. In subjects with diabetes, metoclopramide had no effect on blood pressure, but addition of dopamine raised systolic blood pressure. Neither metoclopramide nor dopamine altered significantly the lipid profile in healthy or diabetic subjects. Dopaminergic drugs increase serum insulin probably by interacting with dopaminergic receptors, but stimulation of beta-adrenergic receptors cannot be ruled out. Stimulation of cardiovascular dopamine receptors also caused modifications of hemodynamic parameters in healthy subjects, but apparently these receptors are attenuated in patients with type 2 diabetes probably as a result of endothelial dysfunction and alterations in the sympathetic nervous system sensitivity.  相似文献   
393.
The possible use of chemical concentrations measured in mussels (Mytillus galloprovincialis) for compliance checking against Environmental Quality Standards (EQS) established for biota is analyzed with the help of an integrated model. The model consists of a 3D planktonic module that provides biomasses in the different compartments, i.e., phytoplankton, zooplankton and bacteria; a 3D fate module that provides the concentrations of contaminants in the water column and in the sediments; and a 3D bioaccumulation module that calculates internal concentrations in relevant biotic compartments. These modules feed a 0D growth and bioaccumulation module for mussels, based on the Dynamic Energy Budget (DEB) approach. The integrated model has been applied to study the bioaccumulation of persistent organic pollutants (POPs) in the Thau lagoon (France). The model correctly predicts the concentrations of polychlorinated biphenyls (PCBs) and polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) in mussels as a function of the concentrations in the water column and in phytoplankton. It also sheds light on the origin of the complexity associated with the use of EQS for biota and their conversion to water column concentrations. The integrated model is potentially useful for regulatory purposes, for example in the context of the European Water Framework (WFD) and Marine Strategy Framework Directives (MSFD).  相似文献   
394.
Serotonin (5-HT) is involved in behaviors such as sleep, eating, memory, in mental disorders like anxiety and depression and plays an important role in the modulation of stress. On the other hand, exposure to stress influence learning as well as declarative and non-declarative memory. These effects are dependent on the type of stressor, their magnitude, and the type of memory. The striatum has been associated with non-declarative procedural memory, while the information about stress effects on procedural memory and their relation with striatal serotonin is scarce. The objective of this study was to evaluate the effects of stress on the modifications of the striatal serotonergic system. In Experiment 1, the effects of either 60 min of restraint (R) or exposure to the elevated T-maze (ETM) was assessed. Exposure to ETM decreased 5-HT concentration and to R increased 5-HT activity ([metabolite]/[neurotransmitter]). In Experiment 2, we evaluated the effects of restraint on ETM trained immediately, 24 or 48 h after restraint. No effects were detected in acquisition or escape latencies, while retention latencies were lower in all groups compared with the non-restrained group, although significant effects were detected immediately and 24h after restraint. The memory impairment seems to be associated with changes in striatal serotonergic system, given that 5-HT concentration increased, while serotonergic activity decreased. The differences in the activity of 5-HT detected in each experiment could be explained by the effects of different stressors on the serotonergic neurons ability to synthesize the neurotransmitter. Thus, we suggest that exposure to stress impairs procedural memory and that striatal serotonin modulates this effect.  相似文献   
395.
396.
Graefe's Archive for Clinical and Experimental Ophthalmology - The aim of the study is to evaluate the effect of topical prostaglandin (PG) treatment on the corneal biomechanical properties in...  相似文献   
397.

Background

A limited number of studies have analyzed prescribing among Medicare-enrolled adults at risk for opioid overdoses. The objectives of this study were to evaluate prescribing for naloxone and central nervous system (CNS) active medications and to determine the relationships of patient characteristics with exposure to these medications.

Methods

This was a retrospective cross-sectional analysis of a Medicare-enrolled medication therapy management eligible cohort. Patients were stratified into two cohorts, individuals with a mean daily morphine milligram equivalent (MME) dose <50 and individuals with MME ≥50. Medications assessed included benzodiazepines, skeletal muscle relaxants (SMR), hypnotics, gabapentanoids, selective-serotonin reuptake inhibitors (SSRI), serotonin–norepinephrine reuptake inhibitors (SNRI), tricyclic antidepressants (TCA), antipsychotics, barbiturates, other antiepileptics, hydroxyzine, and naloxone. Chi-square with odds ratios and logistic regressions determined the relationships of medications and patient characteristics with mean daily MME ≥50. Relationship between medications and opioid dose was adjusted for age and sex.

Results

There were 3452 patients with a daily MME <50 and 1116 with a daily MME ≥50. After adjusting for age and sex, patients with a daily MME ≥50 were more likely to be prescribed hypnotics (OR: 1.41, 95% CI 1.17–1.70), SNRIs (OR: 1.39, 95% CI 1.17–1.64), and naloxone (OR: 3.21, 95% CI 2.49–4.12) (p < 0.001). Nine percent of eligible patients received naloxone. Age groups of persons <85 years of age had 1.58–4.04 (p ≤ 0.004) times the odds of being prescribed a mean daily MME ≥50.

Conclusion

Nearly one-fourth of patients were prescribed a mean daily opioid therapy of MME ≥50. These patients were more likely to be prescribed hypnotics, SNRIs, and naloxone. Patients receiving chronic high-dose opioid therapy were more likely to be in age groups of persons <85 years. Naloxone may be underprescribed among eligible adults. Targeted medication services may ensure optimal prescribing among Medicare patients with chronic opioid therapies.  相似文献   
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