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101.
102.
Lipoprotein (a) is associated with endothelial function in healthy postmenopausal women 总被引:6,自引:0,他引:6
Wilmink HW de Kleijn MJ Bots ML Bak AA van der Schouw YT Engelen S Planellas J Banga J Grobbee DE 《Atherosclerosis》2000,153(1):249-254
BACKGROUND: Lipoprotein (a) (Lp(a)) is an independent risk factor for atherosclerotic cardiovascular disease. The atherogenic potential of Lp(a) may be by impairment of endothelial function. Objectives. We investigated the relation of Lp(a) plasma levels to endothelium dependent and independent dilatation of the brachial artery in healthy postmenopausal women. METHODS: One hundred and five healthy postmenopausal women aged 52-67 years were included in the study. Endothelial function was assessed non-invasively by measuring percent lumen diameter change in the brachial artery after reactive hyperemia and sublingual nitroglycerine spray. RESULTS: Flow mediated dilatation was inversely related to the plasma logLp(a) level. Mean change per unit logLp(a) increase:-2.83% (95% CI: -5.22--0.43). Elevated Lp(a) (>239 mg/l) (upper quartile) was associated with an impaired flow mediated vasodilatation (2.4%+/-1. 2) compared to Lp(a) < or =239 mg/l (5.2%+/-0.7). Adjustment for other cardiovascular risk factors did not change the magnitude of the association. Nitroglycerine-induced vasodilatation was not significantly lower in the high Lp(a) level group, compared to the group with normal levels of Lp(a) (< or =239 mg/l) (8.0+/-1.2 vs. 11.4%+/-0.8). CONCLUSION: Elevated lipoprotein (a) levels are associated with an impaired endothelial function in healthy postmenopausal women, independent of conventional risk factors for cardiovascular disease. Since Lp(a) may be pathogenetically important for early vascular damage, elevated Lp(a) levels might contribute to the increased cardiovascular risk seen in postmenopausal women. 相似文献
103.
Morry Moskovitz MD Colin White MD Roy N. Barnett MD Sydney Stevens RN Edith Russell AB David Vargo MS Dr. Martin H. Floch MD 《Digestive diseases and sciences》1979,24(10):746-751
Increased concentrations of fecal bile acids and neutral sterols or their degradation products have been linked to certain diets and are implicated in colonic carcinogenesis. We measured fecal bile acid and neutral sterol concentrations by thin-layer and gas-liquid chromatography in 15 patients with colonic adenocarcinoma, 23 controls, and 16 patients with nongastrointestinal cancer. We compared these results with dietary intake. Detailed dietary histories showed no differences among the groups in the ingestion of calories, protein, fiber, fat, or carbohydrate. A wide variation in fecal concentration of individual bile acids and neutral sterols was found within each group, but no significant differences in the total bile acid or total neutral sterol per gram dry weight feces were found. Decreased coprostanol, coprostanone, and lithocholic acid excretion was found in the colon cancer group compared with controls. The fecal excretion of all bile acids and neutral sterols was lower significantly in the nongastrointestinal cancer patients with liver metastases as compared with those without. We conclude that total bile acid and total neutral sterol excretion is similar in the three groups, all ingesting similar diets. We cannot confirm reported increased excretion of total bile acids nor excessive bacterial conversion to degradation products in colonic cancer patients. Hepatic metastases correlate with decreased fecal excretion of both bile acids and neutral sterols, which may be due to diminished hepatobiliary excretion. 相似文献
104.
Tumor necrosis factor alpha-induced endothelial tissue factor is located on the cell surface rather than in the subendothelial matrix 总被引:3,自引:0,他引:3
Mulder AB; Hegge-Paping KS; Magielse CP; Blom NR; Smit JW; van der Meer J; Hallie MR; Bom VJ 《Blood》1994,84(5):1559-1566
Because there is no consensus regarding the precise distribution of induced endothelial tissue factor (TF), we studied TF activity in and on tumor necrosis factor alpha-stimulated cultured human umbilical vein endothelial cells (ECs) and their underlying matrix. TF was mainly expressed on the cell surface. Only small traces were found on the apical surface suggesting that TF is predominantly located on the basolateral side of the cell membrane. The presence of TF on the cell surface was confirmed by flow cytometry. Subendothelial TF activity appeared to be dependent upon the procedure used to remove the stimulated EC monolayer. Whereas ammonium hydroxide or hypotonic lysis resulted in relatively high levels of matrix-associated TF, virtually no TF was found on the matrix after mild enzymatic detachment of stimulated ECs. Cell removal with EDTA resulted in intermediate levels of matrix-associated TF. Neither the enzymatic treatment nor EDTA degraded or removed this TF activity. Similar patterns were observed for matrix-associated TF antigen and EC surface markers. Electron microscopic analysis showed cell fragments on the matrix after monolayer lysis. The findings strongly suggest that induced endothelial TF associated with the subendothelial matrix actually represents TF on EC remnants. 相似文献
105.
Purpose:?In this study we assessed whether balance confidence scores changed over a 2-year follow up period, and identified predictors of balance confidence and predictors of change in balance confidence among lower limb amputees.Method:?A prospective follow-up survey of 245 community living adults with unilateral below and above knee lower limb amputation who used their prosthetic limb daily was conducted. Balance confidence, assessed using the 16-item Activity-specific Balance Confidence (ABC) Scale, socio-demographic, health and amputation related variables were collected at baseline and 2 years later.Results:?ABC scores were similar at baseline (mean?= 67.6; SD?=?25.7) and follow up (mean?=?68.0; SD?=?25.8). Lower balance confidence scores at follow up were predicted by older age, being female, use of a mobility device, poor perceived health, increased symptoms of depression, having to concentrate while walking, and fear of falling (all p?<?0.05). Predictors of change in balance confidence included gender and perceived health (all p?<?0.05).Conclusion:?Balance confidence appears to be a persistent problem in the amputee population. Health professionals are encouraged to consider balance confidence as a potentially important variable that may influence function in this clinically unique group of individuals. The identified predictor variables may be useful to clinicians in targeting individuals who require attention to improve balance confidence. 相似文献
106.
Maarten H. M. Raasveld Elisabeth Bloemena Pauline Wertheim-van Dillen Janto Surachno Joep M. Wilmink Ineke J. M. ten Berge 《Transplant international》1993,6(1):42-44
Serum neopterin/creatinine ratios were longitudinally measured in 86 renal transplant recipients from the day before transplantation until 4 months after transplantation, and the relationship to the clinical symptoms of cytomegalovirus (CMV) infection was studied. Infection with cytomegalovirus occurred in 23 patients, 11 cases of which were due to primary infection. Symptoms caused by CMV infection were more severe in male patients, in patients who had received prior antirejection treatment, and in patients with primary CMV infection. The measurement of serum neopterin/creatinine ratios proved to be a marker for the severity of symptoms caused by CMV infection, as peak values were significantly higher in eight patients with CMV disease than in patients with no or only mild symptoms of CMV infection (P<0.05). Moreover, in seven out of eight cases of CMV disease, serum neopterin/creatinine ratios started to rise up to 2 weeks before CMV infection was proven by serology. 相似文献
107.
S. D. Hobbs A. B. M. Wilmink A. W. Bradbury 《European journal of vascular and endovascular surgery》2003,25(6):505-512
INTRODUCTION: the prevalence of peripheral arterial disease (PAD) is relatively well defined for the Caucasian population. Given the susceptibility of Asians and Afro-Caribbeans to coronary heart disease and stroke respectively, and the high prevalence of cardiovascular risk factors in both groups, one would expect a high prevalence of peripheral arterial disease. METHODS: a search of MEDLINE (1966-2002) was undertaken for studies on the incidence and prevalence of PAD, abdominal aortic aneurysms (AAA) and cerebrovascular disease in different ethnic groups. RESULTS: there are very few population-based prevalence studies assessing PAD, AAA or cerebrovascular disease in non-Caucasians. A review of hospital-based series demonstrates different patterns of PAD between ethnic groups. Blacks and Asians have a tendency towards more distal occlusive disease and AAA appear to be predominantly a disease of Caucasians. It is not clear whether these studies provide a true representation of the prevalence of arterial disease in various ethnic groups or are the result of an unmet health care need. CONCLUSIONS: further studies are required to establish the prevalence, natural history and response to treatment of PAD, AAA and cerebrovascular disease in non-Caucasians. Only when this has been achieved, can clinically and cost-effective health care be delivered to affected individuals from different ethnic groups. 相似文献
108.
The clinical significance of gadolinium enhancement of lumbar disc herniations and nerve roots on preoperative MRI 总被引:1,自引:0,他引:1
P. C. A. J. Vroomen S. J. M. Van Hapert R. E. H. Van Acker E. A. M. Beuls A. G. H. Kessels J. T. Wilmink 《Neuroradiology》1998,40(12):800-806
The clinical significance of preoperative gadolinium DPTA enhancement around disc herniations and in the epidural space on
MRI is not clear. The relation of nerve root enhancement to dysfunction also remains controversial. To investigate the clinical
significance of contrast enhancement we looked at the symptoms and signs and gadolinium DPTA-enhanced images of 71 consecutive
surgical candidates in a standardised fashion. Annular rupture and disc enhancement were found to be closely related, and
correlated with sensory loss and paresis, respectively. Nerve root enhancement was found to be related to neurological deficits
in general and sensory impairment in particular.
Received: 4 June 1997 Accepted: 10 March 1998 相似文献
109.
110.
J. Zapletal R. E. M. Hekster J. T. Wilmink J. Hermans J. Schipper W. M. C. Mallens 《European spine journal》1995,4(4):238-241
Summary The purpose of this study was to assess the accuracy of lateral cervical spine radiography in the detection of degenerative atlantoodontoid (AO) osteoarthritis, with CT as gold standard. In 50 patients, lateral radiographs and CT of the AO joint were blindly and independently graded by two radiologists: 0=normal, 1=mild degenerative disease, 2=severe degenerative disease. Radiography was most accurate in distinguishing absent or mild disease from severe disease (83% sensitivity, 84% specificity). Sensitivity in distinguishing absent disease from mild or severe disease was 87%. Specificity however, was low (52%), due to overestimation of the degenerative involvement on radiography. It is concluded that conventional radiography is a useful technique in screening for AO osteoarthritis, especially in severely degenerated joints. However, CT provides the best radiographic detail necessary for accurate diagnosis. 相似文献