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41.
Chest computed tomography (CT), including high-resolution CT with thin (1.5-mm) sections was used to evaluate proved (pathologically or clinically) lymphangitic spread (LS) of tumor in 12 patients. These appearances were compared with thin-section scans obtained in 11 healthy subjects. Thin-section CT demonstrated findings consistent with thickening of the normal lung interstitium. In all patients, thin sections showed an increase in the number of peripheral lines (1-2 cm in length) that were diffuse in generalized disease and localized in focal disease. Normal peripheral arcades were not increased in number, but the limbs forming the arcades were thickened in all patients. A diffuse increase in linear and curvilinear structures (reticular pattern) was seen toward the center of the lung. Polygonal structures 1-2 cm in diameter were seen in seven patients with LS but not in healthy subjects. Fissures were thickened in nine patients. Selected 1.5-mm-thick CT sections are recommended through abnormal areas (seen at CT or on chest radiographs) or if these are normal at three levels (midapex, hilus, and 3 cm above the diaphragm) when scanning patients with tumors known to cause LS. 相似文献
42.
MG Bøe R Salvesen & Å Mygland 《Cephalalgia : an international journal of headache》2009,29(8):855-863
Several studies have shown the benefit of withdrawal therapy when medication overuse headache (MOH) is suspected. Our aim was to compare the effect of withdrawal therapy in patients followed by a neurologist (group A, n = 42) and a primary care physician (PCP) (group B, n = 38). Patients were randomized to A or B, and follow-up was at 3, 6 and 12 months. Calculated mean headache (MH at 6 months + MH at 12 months)/2 (primary end-point) was similar; A 1.04 (0.87, 1.21) and B 1.02 (0.82, 1.21) ( P = 0.87). The number of patients with 50% improvement of headache days was also similar; 14/42 in group A vs. 12/34 in B ( P = 0.86) at 3 months, 15/42 vs. 11/33 ( P = 0.83) at 6 months and 15/42 vs. 14/38 ( P = 0.92) at 12 months. Days without headache during the last 9 months of follow-up were 123 (96, 150) in group A and 137 (112, 161) in B ( P = 0.62). After 3 months one-third were classified as MOH. Patients with MOH improved similarly in group A and B, and so did patients without MOH. Within 1 year 7/42 in A and 9/38 in B had recurrent medication overuse ( P = 0.43). In summary, there were no significant differences in follow-up results between the two groups. 相似文献
43.
44.
Combined oral lysine acetylsalicylate and metoclopramide in the acute treatment of migraine: a multicentre double-blind placebo-controlled study 总被引:3,自引:0,他引:3
H Chabriat JE Joire J Danchot P Grippon MG Bousser 《Cephalalgia : an international journal of headache》1994,14(4):297-300
This multicentre, double-blind, randomized, placebo-controlled, parallel study was designed to evaluate the efficacy of combined oral lysine acetylsalicylate and metoclopramide (LAS-MCP) in the acute treatment of migraine attacks. A total of 266 patients, 18–65 years old, with two to six attacks of migraine with or without aura (IHS criteria) per month were included. The patients had to treat two migraine attacks with LAS-MCP (1620 mg lysine acetylsalicylate-the equivalent of 900 mg aspirin- combined with 10 mg metoclopramide) or placebo. The main outcome measure was headache relief (reduction in headache severity from grade 3 or 2-severe or moderate-to grade 1 or 0-mild or none) 2 h after treatment. LAS-MCP was superior to placebo for headache relief (56% vs 28%) and for the following secondary outcome measures: complete headache relief (18% vs 7%; p < 0.001), nausea (28% vs 44%; p < 0.001), vomiting (3% vs 11%; p = 0.001), use of rescue medication (47% vs 68%; p < 0.001), global efficacy judged as good or excellent (32% vs 14%; p < 0.001). The tolerability was considered as good in 94% of treated attacks in both groups. Combined oral lysine acetylsalicylate and metoclopramide is an effective and well-tolerated acute treatment of migraine attacks. 相似文献
45.
Magdalena Madero Christina L. Wassel Carmen A. Peralta Samer S. Najjar Kim Sutton-Tyrrell Linda Fried Robert Canada Anne Newman Michael G. Shlipak Mark J. Sarnak for the Health ABC Study 《Journal of the American Society of Nephrology : JASN》2009,20(5):1086-1093
Large arteries commonly become stiff in kidney failure, but few studies have investigated arterial stiffness in earlier stages of kidney disease. We evaluated the association between kidney function and aortic pulse wave velocity (aPWV) and its potential modification by race, diabetes, or coronary heart disease in older adults. We measured aPWV in 2468 participants in the Health Aging and Body Composition (Health ABC) study; mean age was 73.7 yr, 40% were black, and 24% had diabetes. After categorizing kidney function into three groups on the basis of cystatin C level, multivariable analysis revealed that the medium and high cystatin C groups associated with a 5.3% (95% confidence interval 0.8 to 10.0%) and 8.0% (95% confidence interval 2.2 to 14.1%) higher aPWV than the low cystatin C group; however, chronic kidney disease, as defined by estimated GFR <60 ml/min per 1.73 m2, did not significantly associate with aPWV. We did not identify interactions between cystatin C and race, diabetes, or coronary heart disease. In conclusion, stiffness of large arteries, a major risk factor for cardiovascular disease, may partially mediate the association between cystatin C and cardiovascular risk in older adults.Cardiovascular disease (CVD) is the primary cause of mortality in patients with kidney failure, accounting for >50% of deaths. Large vessel arterial stiffness is believed to be one of the mechanisms underlying this elevated risk. Recent studies have demonstrated that dialysis patients have less compliant arteries compared with control subjects matched for age and blood pressure (BP).1 Furthermore, both pulse pressure and increased aortic pulse wave velocity (aPWV),2,3 manifestations of large vessel stiffness, are independent risk factors for adverse outcomes in this population.Recent studies have demonstrated that even mildly decreased kidney function is a powerful and independent risk factor for CVD outcomes.4–6 One candidate explanation for this association is that individuals with early stages of kidney disease may have abnormalities in large arterial compliance. This mechanism could be important in older adults, who have increased risk for both kidney disease and CVD.The Health Aging and Body Composition (Health ABC) study is an ideal cohort to study the association of kidney function with vascular stiffness in older adults, because the participants encompass a broad range of kidney function and have large representation of black individuals and patients with diabetes and coronary heart disease (CHD). In addition, Health ABC measured both creatinine and cystatin C at baseline. As a measure of kidney function, cystatin C offers the advantage of not being influenced to the same extent as serum creatinine by gender, race, and muscle mass and particularly in older adults may be a better marker of kidney function.7 Furthermore, cystatin C has been shown to have a more linear relationship with CVD outcomes in older adults, compared with creatinine, which had a J- or U-shaped relationship.4,6 The purpose of this study was to evaluate the association between kidney function, using both cystatin C and creatinine-based estimated GFR (eGFR), and arterial stiffness measured by aPWV in Health ABC. We also evaluated whether any associations would be modified by race, diabetes, or CHD. 相似文献
46.
Joachim H Ix Christina L Wassel Douglas C Bauer Damon Toroian Frances A Tylavsky Jane A Cauley Tamara B Harris Paul A Price Steven R Cummings Michael G Shlipak 《Journal of bone and mineral research》2009,24(3):514-521
Fetuin‐A is a hepatic secretory protein that promotes bone mineralization in vitro. Whether fetuin‐A levels are associated with BMD in humans is unknown. The Health Aging and Body Composition study enrolled 3075 well‐functioning black and white persons 70–79 yr of age and measured BMD. This cross‐sectional study measured serum fetuin‐A using ELISA among a random sample of 508 participants within sex and race strata. Multivariate linear regression analysis evaluated the associations of fetuin‐A with BMD. Among women (n = 257), higher fetuin‐A levels were significantly associated with higher total hip (p = 0.02), lumbar spine (p = 0.03), and whole body BMD (p = 0.01) in models adjusted for age, race, diabetes, alcohol and tobacco use, physical activity, body mass index, C‐reactive protein levels, calcium supplement, and estrogen use. For example, each SD (0.38 g/liter) higher level of fetuin‐A was associated with 0.016 g/cm2 higher total hip areal BMD. The association was of similar magnitude and direction for femoral neck BMD but did not reach statistical significance (p = 0.11). In contrast, among men (n = 251), fetuin‐A had no significant associations with total hip (p = 0.79), lumbar spine (p = 0.35), whole body (p = 0.46), or femoral neck BMD (p = 0.54) in multivariable models. We conclude that higher fetuin‐A levels are independently associated with higher BMD among well‐functioning community‐dwelling older women but not older men. Future studies should evaluate whether fetuin‐A may refine fracture risk assessment in older women. 相似文献
47.
A Choppin I Irwin L Lach MG McDonald AE Rettie L Shao C Becker MP Palme X Paliard S Bowersox DM Dennis P Druzgala 《British journal of pharmacology》2009,158(6):1536-1547
Background and purpose:
Tecarfarin (ATI-5923) is a novel vitamin K epoxide reductase inhibitor that is metabolized by esterase (mainly human carboxylesterase 2) to a single major metabolite, ATI-5900, in rats, dogs and humans. Tecarfarin is not significantly metabolized by CYP450 enzymes. The objective of this study was to test and compare the efficacy of tecarfarin with that of warfarin, when administered either intravenously or once a day orally, to produce stable anticoagulation in beagle dogs.Experimental approach:
Effects on coagulation were assessed by measuring the activity levels of Factor VII and Factor X and thromboplastin-induced coagulation times, reported as prothrombin time (PT).Key results:
Continuous intravenous infusions and oral administration of tecarfarin and warfarin caused a dose-dependent decrease in activity of Factor VII and Factor X, and associated increase in PT. Intravenous fresh frozen canine plasma or subcutaneous vitamin K1 treatment reversed the anticoagulant effects of orally administered tecarfarin. Consistent with the inhibitory effects of amiodarone on CYP2C9, co-administration of amiodarone significantly increased the anticoagulation effect of warfarin and plasma warfarin concentrations. In contrast, amiodarone had no effect on the anticoagulation induced by tecarfarin or tecarfarin plasma concentrations in this model.Conclusions and implications:
Overall, the data presented herein indicate that tecarfarin, via a vitamin K-dependent mechanism, causes changes in key parameters of haemostasis in beagle dogs that are consistent with effective anticoagulation. Compared to warfarin it has a decreased potential to interact metabolically with drugs that inhibit CYP450 enzymes and, therefore, may offer an improved safety profile for patients. 相似文献48.
Ix JH Katz R Kestenbaum B Fried LF Kramer H Stehman-Breen C Shlipak MG 《Journal of the American Society of Nephrology : JASN》2008,19(3):579-585
Coronary artery calcification (CAC) is prevalent and predicts mortality among patients with ESRD, but whether less severe kidney dysfunction is associated with CAC is uncertain. To address this question, 6749 participants of the Multi-Ethnic Study of Atherosclerosis, who were middle-aged and without known cardiovascular disease, were evaluated. Renal function was categorized by cystatin C quartiles and estimated GFR (eGFR; < to >60 ml/min per 1.73 m(2)), and CAC was evaluated by computed tomography (CT). Fifty percent of participants had CAC, mean cystatin C was 0.90 mg/L, and 10% had eGFR <60 ml/min per 1.73 m(2). In unadjusted analysis, kidney dysfunction by either measure was strongly associated with CAC; however, the associations were lost after adjustment for age, gender, race, hypertension, and IL-6 (relative risk 1.04 [95% confidence interval 0.97 to 1.11] for the highest cystatin C quartile compared with the lowest, and relative risk 1.03 [95% confidence interval 0.98 to 1.08] for eGFR below compared with above 60 m/min per 1.73 m(2)). Similarly, neither higher cystatin C nor eGFR <60 was associated with severity of CAC. These results suggest that a higher burden of CAC is unlikely to explain the association between mild to moderate kidney dysfunction and cardiovascular mortality. 相似文献
49.
50.
Keller CR Odden MC Fried LF Newman AB Angleman S Green CA Cummings SR Harris TB Shlipak MG 《Kidney international》2007,71(3):239-244
Inflammatory markers are elevated in persons with estimated glomerular filtration rates less than 60 ml/min/1.73 m2. As cystatin C may detect small changes in kidney function not detected by estimated glomerular filtration rate, we evaluated the association between cystatin C and serum markers of inflammation in older adults with estimated glomerular filtration rate >or=60. This is an analysis using measures from the Health, Aging, and Body Composition Study, a cohort of well-functioning adults aged 70-79 years. Cystatin C correlated with all five inflammatory biomarkers: C-reactive protein (r=0.08), interleukin-6 (r=0.19), tumor necrosis factor alpha (TNF-alpha) (r=0.41), soluble TNF receptor 1 (STNF-R1) (r=0.61), and soluble TNF receptor 2 (STNF-R2) (r=0.54); P<0.0005 for all. In adjusted analyses, cystatin C concentrations appeared to have stronger associations with each biomarker compared with estimated glomerular filtration rate or serum creatinine. Participants with a cystatin C>or=1.0 mg/l had significantly higher levels of all five biomarkers compared to those with a cystatin C<1.0 (mean differences ranging 16-29%, all P<0.05). Cystatin C has a linear association with inflammatory biomarkers in an ambulatory elderly cohort with estimated glomerular filtration rates >or=60; associations are particularly strong with TNF-alpha and the STNF-R. 相似文献