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排序方式: 共有980条查询结果,搜索用时 31 毫秒
971.
Caroline Jaarsma Simon Schalla Emile C Cheriex Martijn W Smulders Ivo van Dongen Patricia J Nelemans Anton PM Gorgels Joachim E Wildberger Harry JGM Crijns Sebastiaan CAM Bekkers 《Journal of cardiovascular magnetic resonance》2013,15(1):5
Background
Although echocardiography is used as a first line imaging modality, its accuracy to detect acute and chronic myocardial infarction (MI) in relation to infarct characteristics as assessed with late gadolinium enhancement cardiovascular magnetic resonance (LGE-CMR) is not well described.Methods
One-hundred-forty-one echocardiograms performed in 88 first acute ST-elevation MI (STEMI) patients, 2 (IQR1-4) days (n = 61) and 102 (IQR92-112) days post-MI (n = 80), were pooled with echocardiograms of 36 healthy controls. 61 acute and 80 chronic echocardiograms were available for analysis (53 patients had both acute and chronic echocardiograms). Two experienced echocardiographers, blinded to clinical and CMR data, randomly evaluated all 177 echocardiograms for segmental wall motion abnormalities (SWMA). This was compared with LGE-CMR determined infarct characteristics, performed 104 ± 11 days post-MI. Enhancement on LGE-CMR matched the infarct-related artery territory in all patients (LAD 31%, LCx 12% and RCA 57%).Results
The sensitivity of echocardiography to detect acute MI was 78.7% and 61.3% for chronic MI; specificity was 80.6%. Undetected MI were smaller, less transmural, and less extensive (6% [IQR3-12] vs. 15% [IQR9-24], 50 ± 14% vs. 61 ± 15%, 7 ± 3 vs. 9 ± 3 segments, p < 0.001 for all) and associated with higher left ventricular ejection fraction (LVEF) and non-anterior location as compared to detected MI (58 ± 5% vs. 46 ± 7%, p < 0.001 and 82% vs. 63%, p = 0.03). After multivariate analysis, LVEF and infarct size were the strongest independent predictors of detecting chronic MI (OR 0.78 [95%CI 0.68-0.88], p < 0.001 and OR 1.22 [95%CI0.99-1.51], p = 0.06, respectively). Increasing infarct transmurality was associated with increasing SWMA (p < 0.001).Conclusions
In patients presenting with STEMI, and thus a high likelihood of SWMA, the sensitivity of echocardiography to detect SWMA was higher in the acute than the chronic phase. Undetected MI were smaller, less extensive and less transmural, and associated with non-anterior localization and higher LVEF. Further work is needed to assess the diagnostic accuracy in patients with non-STEMI. 相似文献972.
973.
Doraiswamy PM Leon J Cummings JL Marin D Neumann PJ 《The journals of gerontology. Series A, Biological sciences and medical sciences》2002,57(3):M173-M177
BACKGROUND: We examined the prevalence of comorbid medical illnesses in Alzheimer's disease (AD) patients at different severity levels. We also examined the effect of cumulative medical comorbidity on cognition and function. METHODS: Analyses of data from 679 AD patients (Mini-Mental State Exam score range 0-30, mean +/- SD = 11.8 +/- 8) from 13 sites (four dementia centers assessing outpatients, four managed care organizations, two assisted living facilities, and three nursing homes) prospectively recruited using a stratification approach including dementia severity and care setting. Medical comorbidity was quantified using the Cumulative Illness Rating Scale-Geriatric. RESULTS: Across patients, 61% had three or more comorbid medical illnesses. Adjusting for age, gender, race, and care setting, medical comorbidity increased with dementia severity (mild to moderate, p <.01; moderate to severe, p <.001). Adjusting for age, educational level, gender, race, and care setting, higher medical comorbidity was associated with greater impairment in cognition (p <.001) and in self-care (p <.001). CONCLUSIONS: Despite the limitation of a cross-sectional design, our initial findings suggest that there is a strong association between medical comorbidity and cognitive status in AD. Optimal management of medical illnesses may offer potential to improve cognition in AD. 相似文献
974.
Kuper HH; van Leeuwen MA; van Riel PL; Prevoo ML; Houtman PM; Lolkema WF; van Rijswijk MH 《Rheumatology (Oxford, England)》1997,36(8):855-860
An assessment of the onset of radiographic damage in the large joints (hip,
knees, shoulders, elbows, ankles and tarsus) in patients with early
rheumatoid arthritis, and the relationship of the progression of large
joint damage with joint damage in hands and feet, with physical disability,
and with cumulative disease activity, was performed in a prospective 6 yr
follow-up study. Large joint damage appeared to be an early phenomenon with
20% of the patients having some damage in at least one large joint within 1
yr, and 50% of the patients within 6 yr after disease onset. Radiographic
damage in large joints was significantly related to the damage in hands and
feet, the physical disability index, and the cumulative disease activity.
The initial disease activity at study entry was the only prognostic factor
that reached significance.
相似文献
975.
Effects of exercise training on older patients with major depression. 总被引:25,自引:0,他引:25
J A Blumenthal M A Babyak K A Moore W E Craighead S Herman P Khatri R Waugh M A Napolitano L M Forman M Appelbaum P M Doraiswamy K R Krishnan 《Archives of internal medicine》1999,159(19):2349-2356
BACKGROUND: Previous observational and interventional studies have suggested that regular physical exercise may be associated with reduced symptoms of depression. However, the extent to which exercise training may reduce depressive symptoms in older patients with major depressive disorder (MDD) has not been systematically evaluated. OBJECTIVE: To assess the effectiveness of an aerobic exercise program compared with standard medication (ie, antidepressants) for treatment of MDD in older patients, we conducted a 16-week randomized controlled trial. METHODS: One hundred fifty-six men and women with MDD (age, > or = 50 years) were assigned randomly to a program of aerobic exercise, antidepressants (sertraline hydrochloride), or combined exercise and medication. Subjects underwent comprehensive evaluations of depression, including the presence and severity of MDD using Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria and Hamilton Rating Scale for Depression (HAM-D) and Beck Depression Inventory (BDI) scores before and after treatment. Secondary outcome measures included aerobic capacity, life satisfaction, self-esteem, anxiety, and dysfunctional cognitions. RESULTS: After 16 weeks of treatment, the groups did not differ statistically on HAM-D or BDI scores (P = .67); adjustment for baseline levels of depression yielded an essentially identical result. Growth curve models revealed that all groups exhibited statistically and clinically significant reductions on HAM-D and BDI scores. However, patients receiving medication alone exhibited the fastest initial response; among patients receiving combination therapy, those with less severe depressive symptoms initially showed a more rapid response than those with initially more severe depressive symptoms. CONCLUSIONS: An exercise training program may be considered an alternative to antidepressants for treatment of depression in older persons. Although antidepressants may facilitate a more rapid initial therapeutic response than exercise, after 16 weeks of treatment exercise was equally effective in reducing depression among patients with MDD. 相似文献
976.
Rh E/e genotyping by allele-specific primer amplification 总被引:1,自引:0,他引:1
Faas BH; Simsek S; Bleeker PM; Overbeeke MA; Cuijpers HT; von dem Borne AE; van der Schoot CE 《Blood》1995,85(3):829-832
It has been shown that the Rhesus (Rh) blood group antigens are encoded by two homologous genes: the Rh D gene and the Rh CcEe gene. The Rh CcEe gene encodes different peptides: the Rh C, c, E, and e polypeptides. Only one nucleotide difference has been found between the alleles encoding the Rh E and the Rh e antigen polypeptides. It is a C-- >G transition at nucleotide position 676, which leads to an amino acid substitution from proline to alanine in the Rh e-carrying polypeptide. Here we present an allele-specific primer amplification (ASPA) method to determine the Rh E and Rh e genotypes. In one polymerase chain reaction, the sense primer had a 3'-end nucleotide specific for the cytosine at position 676 of the Rh E allele. In another reaction, a sense primer was used with a 3'-end nucleotide specific for the guanine at position 676 of the Rh e allele and the Rh D gene, whereas the antisense primer had a 3'-end nucleotide specific for the adenine at position 787 of the Rh CcEe gene. We tested DNA samples from 158 normal donors (including non-Caucasian donors and donors with rare Rh phenotypes) in these assays. There was full concordance with the results of serologic Rh E/e phenotyping. Thus, we may conclude that the ASPA approach leads to a simple and reliable method to determine the Rh E/e genotype. This can be useful in Rh E/e genotyping of fetuses and/or in cases in which no red blood cells are available for serotyping. Moreover, our results confirm the proposed association between the cytosine/guanine polymorphism at position 676 and the Rh E/e phenotype. 相似文献
977.
The immune response to a murine myeloid leukemia (cell line C1498) was studied in vitro and in vivo. Natural killer (NK) cells and CD8+ cytotoxic T lymphocytes (CTL) were shown to lyse C1498 in vitro through the binding of leukocyte function antigen-1 (LFA-1) on effectors and intercellular adhesion molecule-1 (ICAM-1) and ICAM-2 on C1498 target cells. However, the ability of nonimmunized mice to resist an in vivo challenge of a low dose (10(4)) of C1498 was NK-cell, but not T-cell dependent. The failure of T cells to participate in the immune surveillance of a low leukemia burden appeared, in part, because of a lack of expansion of leukemia reactive CTL precursors (CTLp). Leukemia reactive CTLp frequency estimations in naive and leukemia bearing mice were not significantly different (range, 1:20,600 to 1:74,000) in contrast to immunized mice (range, 1:1,400 to 1:4,400). Leukemia reactive CTLp could be expanded to a level that could apparently mediate in vivo immune surveillance of 10(5) leukemia cells by injection of irradiated leukemia cells intraperitoneally (IP) or subcutaneously (SC), but not intravenously (IV). However, IV injection of 10(5) live leukemia cells engineered to secrete interleukin-2 (IL-2) resulted in systemic immunity mediated primarily by CD8+ T cells. We conclude that NK cells can mediate immune surveillance of a low leukemia burden. CD8+ CTL-mediated immune surveillance can eliminate a higher leukemia burden than NK cells, but requires T-cell help, which can be delivered by local IL-2. Both NK and CTL-mediated immune surveillance of C1498 murine myeloid leukemia is dependent on recognition through the LFA-1:ICAM adhesion pathway. 相似文献
978.
Plasma levels of the chemokines monocyte chemotactic proteins-1 and -2 are elevated in human sepsis 总被引:17,自引:1,他引:17
Because of their effects on monocytes, monocyte chemotactic proteins-1 and -2 (MCP-1 and MCP-2) may participate in the pathophysiology of sepsis. We measured circulating MCP-1 and MCP-2 levels in 42 septic patients having positive local or blood cultures. MCP-1 and MCP-2 levels were elevated in 24 (57%) and 25 (59%) of 42 septic patients, respectively, compared with healthy volunteers. Both patients with gram- positive and gram-negative infections had elevated MCP-1 plasma levels (P = .0001) and P < .0001), respectively; Mann-Whitney-U test), whereas patients with gram-positive infection, but not those with gram-negative infection, had increased MCP-2 plasma levels (P= .0182). No relative differences in MCP-1 and MCP-2 plasma levels were observed between several subgroups of patients (sepsis v septic shock; survivors v nonsurvivors), although levels of MCP-1 were the highest in patients with the more severe forms of sepsis, ie, those with shock or a lethal outcome. Serial observations showed that MCP-1 and MCP-2 plasma levels remained elevated for at least 48 hours. MCP-1 correlated weakly with interleukin-8 and MCP-2, the correlations for which were most pronounced in patients with septic shock. MCP-2 correlated with interleukin-8, and surprisingly, with the complement activation product C3a; these correlations further improved when analyzing patients with septic shock or when applying gram-positive infections. Thus, our results not only show increased MCP-1 and MCP-2 levels in patients with sepsis, but also suggest that the synthesis and release of MCP-1 and MCP-2 in sepsis are differently regulated in part. 相似文献
979.
Parker PM; Chao N; Nademanee A; O'Donnell MR; Schmidt GM; Snyder DS; Stein AS; Smith EP; Molina A; Stepan DE 《Blood》1995,86(9):3604-3609
Thalidomide has been reported to be an effective agent for treatment of chronic graft-versus-host disease (CGVHD). To determine the efficacy of this agent in patients with refractory CGVHD a total of 80 patients who failed to respond to prednisone (PSE) or PSE and cyclosporine (CSA) were treated with thalidomide. Sixteen patients (20%) had a sustained response, 9 with a complete remission and 7 with a partial response. Twenty-nine patients (36%) had thalidomide discontinued because of side effects, which included sedation, constipation, neuritis, skin rash, and neutropenia. Side effects were reversible with drug discontinuation except for mild residual neuritis in one case. Rashes and neutropenia have not previously been reported as thalidomide side effects when used for CGVHD treatment. We conclude thalidomide is immunosuppressive and active in the treatment of CGVHD. A high incidence of reversible side effects limited dose intensity and reduced the number of patients who could benefit from treatment. 相似文献
980.
Gap junctional proteins, connexin 26, 32, and 43 in sheep ovaries throughout the estrous cycle 总被引:3,自引:0,他引:3
Anna T. Grazul-Bilska Dale A. Redmer Jerzy J. Bilski Albina Jablonka-Shariff Vinayak Doraiswamy Lawrence P. Reynolds 《Endocrine》1998,8(3):269-279
Ovarian follicles from days 13, 14, 15, and 16 and corpora lutea (CL) from days 2, 4, 8, 12, and 15 of the estrous cycle were
evaluated for the presence of connexins by immunohistochemistry. In addition, CL from days 5, 10, and 15 of the estrous cycle
were used for immunofluorescent detection of Cx43 followed by image analysis, and for Western immunoblot. In all tissues,
staining for all connexins appeared punctate, indicating the presence of assembled gap junctions. Cx26 was present in the
ovarian surface epithelium, stroma, and blood vessels within the stroma and hilus, and in the CL. In healthy antral follicles,
Cx26 was present only in the theca layer, whereas Cx43 was present in granulosa and theca layers. In the majority of atretic
follicles, connexins were not detected, but in 13% of the atretic follicles, Cx43 was present in the theca layer. Cx32 was
detected in the blood vessels of ovarian stroma and in the CL, and Cx43 was detected in the CL. Localization and/or expression
of connexins depended on stage of luteal development. Western analysis demonstrated that expression of Cx32 in luteal tissues
was similar across the estrous cycle. The area of positive staining for Cx43 and expression of Cx43 in luteal tissues decreased
(p < 0.05) as the estrous cycle progressed. The pattern of expression of connexins indicates that gap junctional proteins may
be important in the regulation of folliculogenesis and follicular atresia, as well as growth, differentiation, and regression
of the CL. 相似文献