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111.
This study was designed to examine serum lipid profile and blood pressure in relation to age and sexual maturity. Written informed consent to participate was obtained from 42% of the eligible population of two Devon communities. The blood pressure of 343 boys and 336 girls, aged 11-16 years, was recorded and sufficient blood for analysis was obtained from 320 boys and 301 girls. Of these, sexual maturity of 221 boys and 209 girls was visually assessed using the indices developed by Tanner. In girls there was a significant (p less than 0.05) correlation between age and serum triglyceride level (r = 0.16) and in boys both serum cholesterol and HDL-cholesterol were significantly (p less than 0.01) and negatively correlated with age (r = -0.25 and -0.18 respectively). Girls had significantly higher (p less than 0.05) levels of HDL-cholesterol than boys but neither sex demonstrated significant changes (p greater than 0.05) in serum lipids or lipoproteins with sexual maturity. No significant differences (p greater than 0.05) were detected between the mean diastolic blood pressures of boys and girls but older boys had significantly higher (p less than 0.05) systolic blood pressures than similarly aged girls. Age was positively and significantly correlated (p less than 0.01) with blood pressure in both boys (systolic, r = 0.49; diastolic, r = 0.30) and girls (systolic, r = 0.28; diastolic, r = 0.29). More mature children were demonstrated to have both higher systolic and diastolic blood pressures than less mature children (p less than 0.05) but when allowance was made for school year group through analysis of co-variance the relationship for diastolic blood pressure in boys no longer remained significant. Blood pressures observed in this study do not raise general cause for concern but the data indicate that unfavourable serum lipid and lipoprotein profiles are common.  相似文献   
112.
OBJECTIVES: This study was performed to evaluate the clinical and serial angiographic outcomes of patients undergoing sirolimus-eluting stent (SES) implantation for unprotected left main coronary artery (LMCA) stenosis. BACKGROUND: The efficacy of SES has led to their expanded use for off-label indications, including LMCA disease. METHODS: Unprotected LMCA intervention with SES was attempted in 50 patients. Surveillance angiography was performed at three and nine months' follow-up. RESULTS: The target lesion involved the distal LMCA in 47 patients (94%). In-lesion restenosis occurred in 21 patients (42%), was focal in 85% of cases, and in 82% involved the branch ostia, sparing the LMCA itself. Target lesion revascularization (TLR) occurred in 19 patients (38%) over a mean follow-up of 276 +/- 57 days; TLR was ischemia-driven in 7 patients (14%). Late loss was significantly greater within the left circumflex (LCX) ostium compared to the parent vessel (PV) of the LMCA bifurcation (0.83 +/- 0.89 mm vs. 0.49 +/- 0.72 mm, p = 0.04). Late loss continued to increase between three- and nine-month follow-up. Final minimal luminal diameter and maximal balloon pressure were independent predictors of restenosis of the PV. CONCLUSIONS: Restenosis is a frequent finding when serial angiographic follow-up is performed after SES implantation for unprotected distal LMCA lesions. Restenosis is usually focal, most often involves the LCX ostium, and often occurs without symptoms.  相似文献   
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BACKGROUND: Advanced glycation end products (AGEs) have biological properties that may contribute to the premature cardiovascular mortality of haemodialysis patients. This study examines the hypothesis that low molecular weight forms of fluorescent AGEs (LMW fluorescence) predict mortality in haemodialysis patients. METHODS: The LMW fluorescence was measured in 85 patients treated with chronic haemodialysis and prospectively followed for 4 years. The primary outcome of all-cause mortality was assessed using Cox proportional hazards regression model. RESULTS: At the end of the follow-up period 37 (44%) patients died. The median LMW fluorescence level was 24.2 arbitrary units (range: 10.6-148.1 AU) and the receiver operator characteristic (ROC) curve cut-off for mortality was 37.0 AU. The LMW fluorescence predicted death both as a binary variable at the ROC cut-off, and as a continuous log-transformed variable when adjusted for age, albumin and C-reactive protein (CRP). Adjusted for age, albumin and CRP, the hazard ratio for mortality was 3.05 (1.41-6.60, P = 0.005) for LMW fluorescence as a binary variable and 2.71 per log unit (1.37-5.38, P = 0.004) as a continuous log-transformed variable. CONCLUSION: The low molecular weight forms of AGEs predict mortality in patients receiving chronic haemodialysis, and may be important in the mechanisms leading to atherosclerosis and inflammation in such patients.  相似文献   
115.
The use of haematopoietic stem cell transplantation (HSCT) has now expanded beyond the domain of haematological diseases. Increasingly, the benefits of intense immunosuppression in the management of severe autoimmune diseases are being recognized. In diffuse systemic sclerosis (SSc), there has been increasing evidence of the efficacy of HSCT in improving morbidity and mortality. We present the first Australian patient to undergo autologous HSCT for SSc and review the current literature in the use of HSCT in SSc. Remarkably, the patient had complete resolution of skin disease (modified Rodnan skin score 27/51–0/51), tenosynovitis, synovitis and myositis.  相似文献   
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Acute neurite retraction, elicited by diverse agents in several neuronal cell types, has been reported to be inhibited by genistein, a kinase antagonist that is relatively (though not absolutely) selective for tyrosine kinases. It was hypothesized that genistein acts upon ssome final common pathway that integrates multiple extrinsic and intrinsic signals to regulate whether neurites will execute a retraction response (J. Neurochem., 61 (1993) 340–343). To define this pathway in more detail, a quantitative study of NG108-15 cell rapid-onset neurites was carried out as they retract in response to lysophosphatidic acid (LPA, 10 μM). Following the application of LPA, most neurites exhibited early morphologic changes between 0.5 and 1.5 min, followed by progressive shortening and eventual retraction, with 50% of neurites completely retracted by 5 min and 80% gone by 10 min. Genistein did not inhibit the formation of subcortical F-actin, nor its functional competence in several assays. Genistein protected neurites when added at any time prior to the onset of the earliest morphologic changes, but failed to block progression when added to neurites that were already undergoing retraction. These findings imply that the final common pathway (i.e. the critical target(s) for genistein) must be activated late, after the increase in F-actin levels has peaked and just before retraction is initiated.  相似文献   
119.
OBJECTIVE: The purpose of this study was to determine the efficacy and safety of a targeted narrow band UVB/UVA1 therapy for the treatment of striae alba. METHODS: Fourteen individuals with skin types II-VI were enrolled in this 22-week trial that consisted of up to 10 treatments with a combination of UVB/UVA1 (MultiClear, Curelight Ltd, Israel). Participants were treated with a maximum of 10 treatments unless 100% repigmentation of stretch was achieved prior to the tenth treatment. Biopsies were taken from willing participants at baseline, immediately after the final treatment and 12 weeks after the last treatment. RESULTS: Nine participants completed all treatment visits. After the final treatment, all the participants had >51% repigmentation of the treated striae. At the 4-week follow-up visit, 67% of participants had greater than 51% improvement, and 56% had greater than 51% improvement at the 8-week and 12-week follow-ups. Hyperpigmentation of striae was seen in >50% of the participants treated. The pretreatment biopsies were confirmatory of striae. There were no diagnostic light microscopic differences in the 4-week post-treatment biopsy set available in one patient. CONCLUSION: This high intensity UVB\UVA1 device is an effective and safe modality for the short-term repigmentation of hypopigmented stretch marks. Additional morphologic studies over time are needed to confirm these clinical findings.  相似文献   
120.
OBJECTIVE: Septal-lateral annular cinching ('SLAC') corrects both acute and chronic ischemic mitral regurgitation in animal experiments, which has led to the development of therapeutic surgical and interventional strategies incorporating this concept (e.g., Edwards GeoForm ring, Myocor Coapsys, Ample Medical PS3). Changes in left ventricular (LV) transmural cardiac and fiber-sheet strains after SLAC, however, remain unknown. METHODS: Eight normal sheep hearts had two triads of transmural radiopaque bead columns inserted adjacent to (anterobasal) and remote from (midlateral equatorial) the mitral annulus. Under acute, open chest conditions, 4D bead coordinates were obtained using videofluoroscopy before and after SLAC. Transmural systolic strains were calculated from bead displacements relative to local circumferential, longitudinal, and radial cardiac axes. Transmural cardiac strains were transformed into fiber-sheet coordinates (X(f), X(s), X(n)) oriented along the fiber (f), sheet (s), and sheet-normal (n) axes using fiber (alpha) and sheet (beta) angle measurements. Results: SLAC markedly reduced (approximately 60%) septal-lateral annular diameter at both end-diastole (ED) (2.5+/-0.3 to 1.0+/-0.3 cm, p=0.001) and end-systole (ES) (2.4+/-0.4 to 1.0+/-0.3 cm, p=0.001). In the LV wall remote from the mitral annulus, transmural systolic strains did not change. In the anterobasal region adjacent to the mitral annulus, ED wall thickness increased (p=0.01) and systolic wall thickening was less in the epicardial (0.28+/-0.12 vs 0.20+/-0.06, p=0.05) and midwall (0.36+/-0.24 vs 0.19+/-0.11, p=0.04) LV layers. This impaired wall thickening was due to decreased systolic sheet thickening (0.20+/-0.8 to 0.12+/-0.07, p=0.01) and sheet shear (-0.15+/-0.07 to -0.11+/-0.04, p=0.02) in the epicardium and sheet extension (0.21+/-0.11 to 0.10+/-0.04, p=0.03) in the midwall. Transmural systolic and remodeling strains in the lateral midwall (remote from the annulus) were unaffected. CONCLUSIONS: Although SLAC is an alluring concept to correct ischemic mitral regurgitation, these data suggest that extreme SLAC adversely effects systolic wall thickening adjacent to the mitral annulus by inhibiting systolic sheet thickening, sheet shear, and sheet extension. Such alterations in LV strains could result in unanticipated deleterious remodeling and warrant further investigation.  相似文献   
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