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101.
Pituitary - To review our institutional experience with the surgical management of prolactinomas through the endoscopic endonasal approach with specific focus on cavernous sinus invasion....  相似文献   
102.
ObjectivesThis study characterized the determinants of carotid intima-media thickness (cIMT) in a large (n > 4,000) longitudinal cohort of healthy young people age 9 to 21 years.BackgroundGreater cIMT is commonly used in the young as a marker of subclinical atherosclerosis, but its evolution at this age is still poorly understood.MethodsAssociations between cardiovascular risk factors and cIMT were investigated in both longitudinal (ages 9 to 17 years) and cross-sectional (ages 17 and 21 years) analyses, with the latter also related to other measures of carotid structure and stress. Additional use of ultra-high frequency ultrasound in the radial artery at age 21 years allowed investigation of the distinct layers (i.e., intima or media) that may underlie observed differences.ResultsFat-free mass (FFM) and systolic blood pressure were the only modifiable risk factors positively associated with cIMT (e.g., mean difference in cIMT per 1-SD increase in FFM at age 17: 0.007 mm: 95% confidence interval [CI]: 0.004 to 0.010; p < 0.001), whereas fat mass was negatively associated with cIMT (difference: ?0.0032; 95% CI: 0.004 to ?0.001; p = 0.001). Similar results were obtained when investigating cumulative exposure to these factors throughout adolescence. An increase in cIMT maintained circumferential wall stress in the face of increased mean arterial pressure when increases in body mass were attributable to increased FFM, but not fat mass. Risk factor?associated differences in the radial artery occurred in the media alone, and there was little evidence of a relationship between intimal thickness and any risk factor.ConclusionsSubtle changes in cIMT in the young may predominantly involve the media and represent physiological adaptations as opposed to subclinical atherosclerosis. Other vascular measures may be more appropriate for the identification of arterial disease before adulthood.  相似文献   
103.
Emergency Radiology - Carpal scaphoid fracture is rare in children and is important to recognize early because of an increased risk for serious complications including non-union, avascular...  相似文献   
104.
Predictors of severity and necrosis in acute pancreatitis   总被引:10,自引:0,他引:10  
C-reactive protein remains the single standard biochemical marker for predicting the severity of AP. Because the combination of clinical-physiological scores and CRP provide good information at 48 hours, research has focused on the predictive ability of various markers when applied in the initial 24 hours after admission to the hospital. After detailed review of the literature, the authors conclude that there is no single tool that serves as the optimal predictor of severity. There are, however, data that support the use of certain tests to improve upon the clinician's early predictive ability on the subsequent course of AP. These include an APACHE II score greater than 7 and IL-6 at the time of admission, and urine TAP, urine trypsinogen-2, and serum PMN elastase at 24 hours (Table 4). These markers only will be able to help the clinician's predictive ability if they can be performed locally and if the results can be available ina timely manner. Future research should focus on promising markers such as procalcitonin, IL-8, IL-I ra, sTNFR, CAPAP, PLA-2, novel markers, and the combined use of more than one marker. The conventional research approach in predicting severity used in the last 15 years has limitations and appears to have reached its maximal potential. Novel conceptions and approaches, such as identification of genetic polymorphisms that predispose to severe course and complications of AP or other approaches are needed for a quantum step forward.  相似文献   
105.
106.
AIM: Acute gastrointestinal bleeding is a severe complication in patients receiving long-term oral anticoagulant therapy. The purpose of this study was to describe the causes and clinical outcome of these patients. METHODS: From January 1999 to October 2003, 111 patients with acute upper gastrointestinal bleeding (AUGIB) were hospitalized while on oral anticoagulants. The causes and clinical outcome of these patients were compared with those of 604 patients hospitalized during 2000-2001 with AUGIB who were not taking warfarin. RESULTS: The most common cause of bleeding was peptic ulcer in 51 patients (45%) receiving anticoagulants compared to 359/604 (59.4%) patients not receiving warfarin (P<0.05). No identifiable source of bleeding could be found in 33 patients (29.7%) compared to 31/604 (5.1%) patients not receiving anticoagulants (P=0.0001). The majority of patients with concurrent use of non-steroidal anti-inflammatory drugs (NSAIDs) (26/35, 74.3%) had a peptic ulcer as a cause of bleeding while 32/76 (40.8%) patients not taking a great dose of NSAIDs had a negative upper and lower gastrointestinal endoscopy. Endoscopic hemostasis was applied and no complication was reported. Six patients (5.4%) were operated due to continuing or recurrent hemorrhage, compared to 23/604 (3.8%) patients not receiving anticoagulants. Four patients died, the overall mortality was 3.6% in patients with AUGIB due to anticoagulants, which was not different from that in patients not receiving anticoagulant therapy. CONCLUSION: Patients with AUGIB while on long-term anticoagulant therapy had a clinical outcome, which is not different from that of patients not taking anticoagulants. Early endoscopy is important for the management of these patients and endoscopic hemostasis can be safely applied.  相似文献   
107.
Although active smoking is known to enhance platelet thromboxane production, no data on passive smoking are available yet. In an 18 m3 room, the influence of single and repeated exposure to passive smoke for 60 minutes was assessed in nonsmokers and smokers. Smokers and nonsmokers were matched for sex and age. All the evaluated parameters (plasma TXB2, serum TXB2, malondialdehyde, 11-dehydro-TXB2, conversion of exogenous arachidonic acid to hydroxy-5,8,10-heptadecatrienoic acid, and TXB2) were higher in smokers than nonsmokers at baseline conditions, immediately and 6 hours after passive exposure to cigarette smoke. Repeated exposure of nonsmokers rendered their platelets more activated, so they became closer to the behavior of smokers. Contributing to the development of hemostatic imbalance, these results indicate that passive smoking may enhance thromboxane A2 release from the platelets.Presented at the 36th Annual World Congress, International College of Angiology, New York, New York, July 1994  相似文献   
108.
Indoleamine 2,3-dioxygenase (IDO) suppresses adaptive immunity. T-cell proliferation and differentiation to effector cells require increased glucose consumption, aerobic glycolysis and glutaminolysis. The effect of IDO on the above metabolic pathways was evaluated in alloreactive T-cells. Mixed lymphocyte reaction (MLR) in the presence or not of the IDO inhibitor, 1-methyl-dl-tryptophan (1-MT), was used. In MLRs, 1-MT decreased tryptophan consumption, increased cell proliferation, glucose influx and lactate production, whereas it decreased tricarboxylic acid cycle activity. In T-cells, from the two pathways that could sense tryptophan depletion, i.e. general control nonrepressed 2 (GCN2) kinase and mammalian target of rapamycin complex 1, 1-MT reduced only the activity of the GCN2 kinase. Additionally 1-MT treatment of MLRs altered the expression and/or the phosphorylation state of glucose transporter-1 and of key enzymes involved in glucose metabolism and glutaminolysis in alloreactive T-cells in a way that favors glucose influx, aerobic glycolysis and glutaminolysis. Thus in alloreactive T-cells, IDO through activation of the GCN2 kinase, decreases glucose influx and alters key enzymes involved in metabolism, decreasing aerobic glycolysis and glutaminolysis. Acting in such a way, IDO could be considered as a constraining factor for alloreactive T-cell proliferation and differentiation to effector T-cell subtypes.  相似文献   
109.
The endothelium of the vessel wall as a barrier between blood and the subendothelial matrix proteins is essential for preventing thrombus formation and subsequent atherosclerosis development. Atherosclerosis is an inflammatory disease in which immune and autoimmune mechanisms are involved. Recently, it was demonstrated that endothelial cells in the vessel wall can be damaged not only by classic risk factors, such as hyperlipidemia, smoking and disturbed blood flow, but also (auto)immune reactions to autoantigens present in the cell surface, among which heat shock protein 60 (HSP60) was mostly studied. HSP60 normally located in mitochondria can be translocated into the cell member in response to stress stimuli. Meanwhile, autoantibodies against HSP60 are present in most subjects, especially patients with heart attack and stroke. These autoantibodies may bind to HSP60 expressed in endothelial cells resulting in the cell damage, subsequently initiating the formation of atherosclerotic lesions. Based on the recent progress in the research field, the present review will update the mechanisms of immune response to endothelial cells by which cell damage can initiate the development of atherosclerosis.  相似文献   
110.
Integrating information across different senses is a central feature of human perception. Previous research suggests that multisensory integration is shaped by a context-dependent and largely adaptive interplay between stimulus-driven bottom-up and top-down endogenous influences. One critical question concerns the extent to which this interplay is sensitive to the amount of available cognitive resources. In the present study, we investigated the influence of limited cognitive resources on audiovisual integration by measuring high-density electroencephalography (EEG) in healthy participants performing the sound-induced flash illusion (SIFI) and a verbal n-back task (0-back, low load and 2-back, high load) in a dual-task design. In the SIFI, the integration of a flash with two rapid beeps can induce the illusory perception of two flashes. We found that high compared with low load increased illusion susceptibility and modulated neural oscillations underlying illusion-related crossmodal interactions. Illusion perception under high load was associated with reduced early β power (18–26 Hz, ∼70 ms) in auditory and motor areas, presumably reflecting an early mismatch signal and subsequent top-down influences including increased frontal θ power (7–9 Hz, ∼120 ms) in mid-anterior cingulate cortex (ACC) and a later β power suppression (13–22 Hz, ∼350 ms) in prefrontal and auditory cortex. Our study demonstrates that integrative crossmodal interactions underlying the SIFI are sensitive to the amount of available cognitive resources and that multisensory integration engages top-down θ and β oscillations when cognitive resources are scarce.SIGNIFICANCE STATEMENT The integration of information across multiple senses, a remarkable ability of our perceptual system, is influenced by multiple context-related factors, the role of which is highly debated. It is, for instance, poorly understood how available cognitive resources influence crossmodal interactions during multisensory integration. We addressed this question using the sound-induced flash illusion (SIFI), a phenomenon in which the integration of two rapid beeps together with a flash induces the illusion of a second flash. Replicating our previous work, we demonstrate that depletion of cognitive resources through a working memory (WM) task increases the perception of the illusion. With respect to the underlying neural processes, we show that when available resources are limited, multisensory integration engages top-down θ and β oscillations.  相似文献   
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