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91.
Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
  相似文献   
92.
Summary Antiperinuclear factor (APF) and IgG-rheumatoid factor (IgG-RF) has been found in 64% and 48% of cases of rheumatoid arthritis, 36% and 50% of cases of psoriasis and 31% and 45% of cases of primary Sjögren's syndrome. A close relationship between APF and IgG-RF is suggested by statistical and experimental data. Purified IgG-RF has some degree of APF activity.  相似文献   
93.
OBJECTIVE: The objective was to examine the safety and efficacy of the 48th Combat Support Hospital's use of diagnostic endoscopy in Afghanistan. METHODS: A retrospective review was performed on the medical records of all endoscopy patients treated at the 48th Combat Support Hospital in Bagram, Afghanistan, from December 6, 2002 through June 7, 2003. RESULTS: Twenty-four patients (male, 21; female, 3; mean age, 35 years) underwent 28 endoscopic procedures as follows: colonoscopy, 14; esophagogastroduodenoscopy (EGD), 13; and flexible sigmoidoscopy, 1. Four patients underwent both EGD and colonoscopy. There were no complications. Of the 18 U.S. military patients, 3 (15%) were evacuated for further evaluation and/or treatment and 1 (5%) patient underwent an elective screening colonoscopy. For 14 of 17 U.S. military personnel (82%), the endoscopic procedures obviated evacuation from Afghanistan. CONCLUSIONS: Diagnostic colonoscopy and EGD were valuable and safe adjuncts that precluded evacuations out of theater for 82% of military patients. Endoscopy should be used when U.S. military operations necessitate the deployment of large numbers of forces for protracted periods.  相似文献   
94.
COVID-19 has been sweeping the globe, hitting the United States particularly hard with a state of emergency declared on March 13, 2020. Transplant hospitals have taken various precautions to protect patients from potential exposure. OPTN donor, candidate, and transplant data were analyzed from January 5, 2020 to September 5, 2020. The number of new waiting list registrations decreased, with the Northeast seeing over a 50% decrease from the week of 3/8 versus the week of 4/5. The national transplant system saw near cessation of living donor transplantation (−90%) from the week of 3/8 to the week of 4/5. Similarly, deceased donor kidney transplant volume dropped from 367 to 202 (−45%), and other organs saw similar decreases: lung (−70%), heart (−43%), and liver (−37%). Deceased donors recovered dropped from 260 to 163 (−45%) from 3/8 compared to 4/5, including a 67% decrease for lungs recovered. The magnitude of this decrease varied by geographic area, with the largest percent change (−67%) in the Northeast. Despite the pandemic, discard rates across organ has remained stable. Although the COVID-19 pandemic continues to evolve, OPTN data show recent evidence of stabilization, an indication that an early recovery of the number of living and deceased donors and transplants has ensued.  相似文献   
95.
96.
Astrocytes have essential roles for neuron survival and function, so that their demise in neurodegenerative insults, such as ischemia, deserves attention. A major event of the cell death cascade in ischemia is the reversed operation of excitatory amino acid transporters (EAAT), releasing glutamate. Cytotoxicity is conventionally attributed to extracellular glutamate accumulation. We previously reported that mimicking such dysfunction by EAAT substrate inhibitors, whose uptake induces glutamate release by heteroexchange, triggers glutathione (GSH) depletion and oxidative death of differentiated astrocytes in culture. Here we demonstrate that astrocyte death, although correlated with glutamate release, is not resulting from high extracellular glutamate-mediated toxicity. L-glutamate per se was gliotoxic only at concentrations much higher than the maximum reached with the potent EAAT substrate inhibitor L-trans-pyrrolidine-2,4-dicarboxylate (PDC), and toxicity was lower. Moreover, high glutamate concentrations offered protection against PDC. Protection was also provided by L-aspartate, which is both transported by EAAT and metabolized into glutamate, and by inhibiting glutamine synthetase, which uses transported glutamate to synthesize glutamine. Neither D-aspartate, a metabolically inert EAAT substrate, nor compounds that can provide glutamate intracellularly but are not EAAT substrates offered protection. Interestingly, only the compounds providing protection prevented PDC-induced GSH depletion. These data strongly suggest that reversed uptake-mediated astrocyte death results from the leakage of glutamate from a compartmentalized intracellular metabolic pool specifically fuelled by EAAT, crucial for preserving GSH contents. In addition, we provide evidence for a minor contribution of the cystine-glutamate antiporter x(c) (-) but a major role of the 5-lipoxygenase pathway in this death mechanism.  相似文献   
97.

Background:

The relationship between cardiovascular disease (CVD) risk factors and dietary intake is unknown among individuals with spinal cord injury (SCI).

Objective:

To investigate the relationship between consumption of selected food groups (dairy, whole grains, fruits, vegetables, and meat) and CVD risk factors in individuals with chronic SCI.

Methods:

A cross-sectional substudy of individuals with SCI to assess CVD risk factors and dietary intake in comparison with age-, gender-, and race-matched able-bodied individuals enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Dietary history, blood pressure, waist circumference (WC), fasting blood glucose, high-sensitivity C-reactive protein (hs-CRP), lipids, glucose, and insulin data were collected from 100 SCI participants who were 38 to 55 years old with SCI >1 year and compared to 100 matched control participants from the CARDIA study.

Results:

Statistically significant differences between SCI and CARDIA participants were identified in WC (39.2 vs 36.2 in.; P < .001) and high-density lipoprotein cholesterol (HDL-C; 39.2 vs 47.5 mg/dL; P < .001). Blood pressure, total cholesterol, triglycerides, glucose, insulin, and hs-CRP were similar between SCI and CARDIA participants. No significant relation between CVD risk factors and selected food groups was seen in the SCI participants.

Conclusion:

SCI participants had adverse WC and HDL-C compared to controls. This study did not identify a relationship between consumption of selected food groups and CVD risk factors.Key words: cardiovascular disease risk factors, dietary intake, spinal cord injuryCardiovascular disease (CVD) is a leading cause of death in individuals with chronic spinal cord injuries (SCIs).15 This is partly because SCI is associated with several metabolic CVD risk factors, including dyslipidemia,610 glucose intolerance,6,1114 and diabetes.1517 In addition, persons with SCI exhibit elevated markers of inflammation18,19 and endothelial activation20 that are correlated with higher CVD prevalence.2123 Obesity, and specifically central obesity, another CVD risk factor,2426 is also common in this population.12,2729Dietary patterns with higher amounts of whole grains and fiber have been shown to improve lipid abnormalities,30 glucose intolerance, diabetes mellitus,3134 hypertension,35 and markers of inflammation36 in the general population. These dietary patterns are also associated with lower levels of adiposity.31 Ludwig et al reported that the strong inverse associations between dietary fiber and multiple CVD risk factors – excessive weight gain, central adiposity, elevated blood pressure, hypertriglyceridemia, low high-density lipoprotein cholesterol (HDL-C), high low-density lipoprotein cholesterol (LDL-C), and high fibrinogen – were mediated, at least in part, by insulin levels.37 Whole-grain food intake is also inversely associated with fasting insulin, insulin resistance, and the development of type 2 diabetes.32,38,39Studies in the general population have also shown a positive association between the development of metabolic syndrome as well as heart disease and consumption of a Western diet, a diet characterized by high intake of processed and red meat and low intake of fruit, vegetables, whole grains, and dairy.40,41 Red meat, which is high in saturated fat, has been shown to have an association with adverse levels of cholesterol and blood pressure and the development of obesity, metabolic syndrome, and diabetes.40,42,43Numerous studies have shown that individuals with chronic SCI have poor diet quality.4449 A Canadian study found that only 26.7% of their sample was adherent to the recommendations about the consumption of fruit, vegetables, and grains from the “Eating Well with Canada’s Food Guide.”44 Individuals with chronic SCI have also been found to have low fiber and high fat intakes when their diets were compared to dietary recommendations from the National Cholesterol Education Program,46 the 2000 Dietary Guidelines for Americans,49 and the recommended Dietary Reference Intakes and the Acceptable Macronutrient Distribution Range.47,48However, unlike in the general population, the relationship between dietary intake and obesity and CVD risk factors is unknown in the chronic SCI population. If a dietary pattern consisting of higher intake of whole grains and dietary fiber is favorably associated with obesity and CVD risk factors in individuals with chronic SCI, then trials of increased intake of whole grains and fiber intake could be conducted to document health benefits and inform recommendations. The purpose of this pilot study is to investigate the association between selected food group intake and CVD risk factors in individuals with chronic SCI as compared to age-, gender-, and race-matched able-bodied individuals enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Data will also be used to plan future studies in the relatively understudied field of CVD and nutrition in individuals with SCI.  相似文献   
98.
Hyperactivity of striatal glutamatergic synaptic transmission in response to dopamine depletion plays a major role in the pathogenesis of parkinsonian motor symptoms. In the present study we investigated the impact, on this hyperactivity, of chronic dyskinesiogenic L-DOPA treatment, combined or not with high-frequency stimulation (HFS) of the subthalamic nucleus (STN). In vitro patch-clamp recordings were performed from striatal spiny neurons of hemiparkinsonian rats (intranigral 6-OHDA injection). Here we show that dyskinesiogenic L-DOPA treatment exacerbated striatal glutamatergic hyperactivity induced by 6-OHDA lesion. Chronic 5-day STN HFS had the opposite effect, reducing striatal glutamatergic transmission in both parkinsonian and dyskinetic animals. Consistently, chronic HFS stimulation could progressively ameliorate motor parkinsonian signs (akinesia) but, conversely, did not improve L-DOPA-induced dyskinesia (LID). Thus, the effects of L-DOPA and HFS on corticostriatal transmission seem to be dissociated. These data show for the first time that dyskinesiogenic L-DOPA treatment and chronic STN HFS with antiakinetic effects induce opposite plastic rearrangements in the striatum. The interaction between these two treatments provides further evidence that striatal glutamatergic hyperactivity is a pathophysiological correlate of akinesia rather than LID.  相似文献   
99.
Background Limited attention has been devoted to characterizing unmet need for treatment among individuals with mental disorders. A longitudinal follow-up of depressed, anxious, and psychiatrically normal children into adulthood provided an opportunity to examine factors associated with subjective unmet need.Methods Respondents (n = 208) comprise a subsample of a cohort ascertained between 1977 and 1985 consisting of three subgroups: one with major depressive disorder (MDD), one with anxiety disorders but no MDD, and controls with no psychiatric disorder up to ascertainment. Psychiatric status was reassessed in adulthood using the SADS-LA by interviewers blind to childhood diagnoses. Best-estimate diagnoses describing participants’ lifetime clinical course were formulated by senior clinicians. Participants who completed SADS-LA interviews about themselves were invited to complete an additional interview about experiences with health care, including subjective unmet need for and barriers to mental health treatment.Results About 37% of respondents reported lifetime histories of subjective unmet need for mental health services. Unmet need was associated with female gender and lifetime mood and substance dependence disorders. The most commonly cited barriers included attitudes toward treatment, not knowing where to obtain it, and financial concerns.Conclusions Subjective unmet need was common in this sample. Approaches to reducing it might include public health initiatives to foster more favorable attitudes toward treatment, increase knowledge of where to obtain it, and lower financial barriers.  相似文献   
100.
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