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101.
Various studies have already shown that the fatty acid composition of dietary fat has different effects on hemostasis and platelet function. However, knowledge on this topic is incomplete. In the present study, fifty-eight healthy students received either a 4-week rapeseed oil [high content of monounsaturated fatty acids (MUFA) and high n-3/n-6 PUFA ratio], an olive oil (high content of MUFA, low n-3/n-6 PUFA ratio) or a sunflower oil (low content of MUFA, low n-3/n-6 PUFA ratio) diet. In each group, effects on hemostatic parameters were compared with a wash-in diet rich in saturated fatty acids with respect to intermediate-time effects on the hemostatic system and platelet function. With the olive oil diet, a reduction of coagulation factors VIIc, XIIc, XIIa, and Xc was found, whereas sunflower oil led to lower values of coagulation factors XIIc, XIIa, and IXc. In all study groups levels of plasmin-alpha2-antiplasmin were lower in week 4 than at baseline. Lower fibrinogen binding on platelets was found after the sunflower oil diet, whereas expression of CD62 and spontaneous platelet aggregation were slightly higher after the olive oil diet. However, given the major differences in the fatty acid compositions of the diets, the differences between the groups with respect to hemostasis tended to be small. Therefore, the clinical significance of the present findings remains to be evaluated.  相似文献   
102.
103.
Information on the effects of newer antiepileptic drug (AEDs) on the electroencephalogram (EEG) is sparse and contradictory. Quantitative EEG (qEEG) provides a method of estimating the effects of drugs on the central nervous system. Twenty-three adult patients with difficult-to-control complex partial seizures, with or without secondary generalization, participated in an add-on study with one of three newer AEDs: vigabatrin (n = 10), lamotrigine (n = 6), and topiramate (n = 7). Frequency analysis and topographic mapping of awake EEGs before and during treatment with the drug were compared. Statistical analysis was performed using 2-way analysis of variance (ANOVA) with repeated measures. Vigabatrin administration was followed by a diffuse decrease in the absolute alpha (p < 0.05) and beta (p < 0.02) activities and a decrease in the absolute theta in the frontal and parieto-occipital regions (p < 0.03). Lamotrigine caused a significant diffuse increase in the faster frequencies (relative alpha p < 0.04 and relative beta p < 0.02), and decrease in the slower activities (relative theta in the posterior head regions p < 0.03 and relative delta diffusely p < 0.05). Topiramate increased the absolute beta (p < 0.05) and theta (p < 0.02) activities diffusely and decreased the relative alpha activity over the left hemisphere (p < 0.03). The different effect profiles of the newer AEDs on the electrical brain activity may reflect their different mechanisms of action.  相似文献   
104.
Purpose The aim of the study is to determine whether a biodegradable elastomeric device that uses an osmotic pressure delivery mechanism can release different therapeutic proteins at a nearly constant rate in nanomolar concentrations with high bioactivity, given the same formulation conditions. Vascular endothelial growth factor (VEGF) and interleukin-2 (IL-2) were embedded in the device as sample therapeutic proteins, and their release and bioactivity were compared to that achieved previously with interferon-γ (IFN-γ). Methods A photo-cross-linkable biodegradable macromer consisting of acrylated star(ɛ-caprolactone-co-d,l-lactide) was prepared. VEGF, IL-2, and IFN-γ were co-lyophilized with serum albumin and trehalose at different ratios and were then embedded into the elastomer by photo-cross-linking the lyophilized particles in a macromer solution. The protein mass and the bioactivity in the release supernatant were measured by enzyme-linked immunosorbent and cell-based assays. Results VEGF, IL-2, and IFN-γ were released at the same, nearly constant rate of 25.4 ng/day for over 18 days. Using the optimum elastomer formulation, the release profiles of the proteins were essentially identical, and their rates were linear and constant. Cell-based bioactivity assays showed that 70 and 88% of the released VEGF and IL-2, respectively, were bioactive. The rate of protein release can be adjusted by changing the trehalose loading concentration in the elastomer matrix without altering the linear nature of the protein release kinetics. The elastomeric device degraded in PBS buffer within 85 days. Conclusions The elastomer formulation shows promising potential as a sustained protein drug delivery vehicle for local delivery applications.  相似文献   
105.
Successful pregnancy in humans depends on deep invasion of the maternal decidua by extravillous trophoblast cells (EVTs), a process regulated by autocrine and paracrine signals in the decidual-trophoblast microenvironment. Here we examined whether trophoblast invasion is affected by decidual differentiation of endometrial stromal cells (ESC) and modulated locally by cytokines and growth factors. Trophoblast spheroids were generated from the EVT-derived cell line AC-1M88 and placed onto monolayers of either undifferentiated or decidualized ESC, or directly onto tissue culture surface. Co-cultures were treated with epidermal growth factor (EGF), hepatocyte growth factor, heparin-binding EGF-like growth factor (HB-EGF), interleukin-1β (IL-1β) and leukaemia inhibitory factor (LIF). Expansion of spheroids over 2-3 days was significantly enhanced by a monolayer of undifferentiated ESC compared with tissue culture surface and further increased if ESC had been decidualized. HB-EGF and IL-1β, alone or in combination with LIF, stimulated spheroid expansion but only on undifferentiated ESC. CEACAM1, an adhesion molecule implicated in trophoblast invasion, was up-regulated in AC-1M88 cells by conditioned medium from decidualized ESC, and by HB-EGF, IL-1β and LIF in combination. Treatment of ESC with HB-EGF or IL-1β increased the level of the tetraspanin CD82, a metastasis suppressor found in decidual cells at the implantation site. We suggest that decidualized ESC support trophoblast invasion by paracrine signals that may include HB-EGF, IL-1β and LIF.  相似文献   
106.
Enhanced risk of coronary heart disease mortality in lean hypertensive men   总被引:2,自引:0,他引:2  
A recently presented hypothesis contends that the excess coronary heart disease mortality associated with hypertension is more prominent in lean men than in overweight men. This hypothesis was addressed using data collected in the Israeli Ischemic Heart Disease Study (n = 10,059). The ratios of age-adjusted 15-year death rates in hypertensive and normotensive men were 4.7, 2.8, 2.0, and 1.9 in the Quetelet index groups of less than 2.29, 2.29 to 2.56, 2.56 to 2.83 and greater than 2.83 g/cm2, respectively. The corresponding ratios for all-cause mortality were 2.2, 2.1, 2.0, and 1.7, respectively. The group with the highest all-cause age-adjusted mortality, at 33.6%, was that of the leanest (less than 2.29 g/cm2, bottom 20% of the Quetelet index distribution) hypertensive subjects. The same group also displayed the highest coronary heart disease mortality (age-adjusted rate, 18.2%). The findings persisted for both smokers and nonsmokers and after exclusion of men with coronary heart disease or diabetics at intake, men on antihypertensive medication, or those who died in the first 2 years of follow-up (1963-1965). A multivariate risk score for developing myocardial infarction was calculated, based on levels of age, systolic blood pressure, total cholesterol, high density lipoprotein cholesterol, cigarette smoking, diabetes mellitus, and Quetelet index. This score varied little across the four Quetelet index groups in hypertensive men: 5-year mean estimated risks of myocardial infarction were between 70 and 74/1000. In normotensive men the scores increased from 19/1000 in the leanest subjects to 29/1000 in the overweight ones.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
107.
108.
Extracellular matrix of the human optic nerve head   总被引:2,自引:0,他引:2  
Double-antibody immunofluorescent studies of sectioned human optic nerve head indicated the marked presence of collagen type IV and laminin in the extracellular matrix of the lamina cribrosa. These macromolecules were layered transversely across the nerve fascicles and appeared to constitute the cribriform plates. Relatively little collagen types III and I were present in the extracellular matrix of this tissue and fibronectin was not detected in appreciable amounts. These results indicated that the lamina cribrosa contains a specialized extracellular matrix of the central nervous system made up of plates of material resembling basement membrane. The major macromolecular components of the lamina cribrosa do not resemble those of sclera.  相似文献   
109.
The Comprehensive Periodic Assessment Form is a new format used to document a patient's rehabilitation progress. It is a nonnarrative, semi-graphical form in which is digested on one page many sheets of progress notes from a variety of disciplines. Mobility, ADL, mental, and medical status overtime can be ascertained at a glance. The form has special utility for the aged patient experiencing rehabilitation treatment.  相似文献   
110.
The effects of a new micropore transfusion filter (Fenwal 4C2423) on stored whole blood have been examined. Five filters were preloaded by passage of two units of outdated type specific bank blood, and the effects of filtration on a third unit, consisting of 21-day-old blood, flowing under 150 mmHg pressure, were measured. Filtration did not significantly alter red blood cell count, total hemoglobin, red blood cell fragility, plasma sodium, potassium, albumin, or globulin. Some platelets and white blood cells were removed and a small amount of hemolygis of erythrocytes (less than 0.1%) was observed. Removal of microaggregates, assessed by Coulter counting, screen filtration pressure, total screen porteins, wet and dry weights of material retained, and scanning electron microscopy, was shown to be excellent over the entire range of particle size. Comparison of the Bentley PFS-127, Fenwal 4C2417, Johnson & Johnson Intersept, Pall Ultipore, and Swank IL200 filters led to the conclusion that the Fenwal 4C2423 was both a significant improvement over the previous Fenwal design and comparable to the most efficient of these filters for both the removal of microaggregates during massive blood transfusion and for the blood flow rates obtained.  相似文献   
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