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81.
This study was designed to measure the effect of dietary n−3 fatty acids (FA) on platelets and blood lipids. Healthy men (n=9), ages 31 to 65, were fed diets in which salmon was the source of n−3 fatty acids. They were confined in a nutrition suite at this Center for 100 days. Food intake and exercise levels were rigidly controlled. Initially they were placed on a stabilization diet for 20 days, then six men were fed the salmon diet for 40 days. The others remained on the stabilization diet. The two groups switched diets for the last 40 days of the study. Both diets were isocaloric [16% protein, 54% carbohydrate, and 30% fat by energy-% (En%)]. The salmon diet contained 7.5% of calories from n−6 FA and 2% from n−3 FA, primarily eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in a 40∶60 ratio, while the stabilization diet contained 7.5% of calories from n−6 FA and less than 0.3% n−3 FA, mainly 18∶3n−3. The bleeding time was unaffected by the diets in this study. The prothrombin time was shortened (11.6 sec.vs. 12.6 sec., p<0.01) for the subjects consuming the salmon diet as compared to that measured after 20 days of the stabilization diet. Mean platelet volume increased significantly during the period in which the volunteers consumed the salmon diet compared to the baseline diet (p<0.01), while the mean platelet levels decreased. Platelet aggregation (PA) was measured in platelet rich plasma before, during, and after the salmon diet using collagen, ADP, arachidonic acid (AA), and thrombin agonists. The PA threshold for ADP was significantly increased for the subjects on the salmon diet (p<0.05). No change in the PA threshold was detected for collagen or thrombin. The PA threshold for AA was unchanged also, but the platelets in subjects consuming the salmon diet had a prolonged time to maximum aggregation (p<0.01) with this reagent compared to platelets from men on the stabilization diet. Plasma, red cell, and platelet total FA composition was determined by capillary GLC. While the men consumed the salmon diets, there were marked increases (3 to 10-fold) in the EPA and DHA levels in all blood components with concomitant decreases in linoleic acid and AA levels. Thus, a salmon diet, high in n−3 FA, did not influence the bleeding times, but it decreased the sensitivity of platelets to ADP and AA, increased the mean platelet size, decreased the platelet count, and changed the FA composition of the plasma, RBC and platelet membrane lipids.  相似文献   
82.
The Bay of Vidy is the most contaminated area of Lake Geneva, Switzerland, as a result of the release of treated and untreated waste water from the municipal sewage treatment plant of the city of Lausanne and its surroundings. The reconstruction of the historical deposition of heavy metals in the sediment of the bay has been performed by the analysis of several dated (radiocaesium) sediment cores. The presence of sewage‐derived contaminants in the Bay of Vidy since the beginning of the sewage treatment plant's operations in 1964 is clearly observed, when a sharp increase in heavy metal contents is recorded, with maximum concentrations of cadmium, copper, zinc and lead occurring between the late 1960s and early 1970s. Despite considerable improvement in recent times, the present concentrations of the investigated heavy metals in sediments of the Bay of Vidy are still higher than concentrations measured at the centre of the lake, the latter close to Lake Geneva's natural background values. It is concluded that the quantity of heavy metals deposited in the bay is considerable and, because of sediment instability, will constitute a potential hazard for biota.  相似文献   
83.
A series of 238 hydronephrotic kidneys in 219 children is reported. The condition was more common in the male than in the female subject and occurred more frequently on the left side. It was often bilateral, especially in infants, with an abdominal mass as the common presenting feature. Loin or abdominal pain was the most frequent complaint in older children. In some cases hydronephrosis presented as a ruptured kidney following trauma. Only 1 patient was hypertensive. The lesion was asymptomatic in 18 cases and the incidence of urinary infection was low. Dismembered pyeloureteroplasty was the procedure of choice for reconstruction. Preliminary nephrostomy was used rarely and nephrectomy was done in 10 per cent of the kidneys. Of the 7 reoperations 4 were for persistent obstruction and 3 were because stones had formed after the pyeloplasty. The late results, assessed clinically and radiologically, have been entirely satisfactory. Many kidneys of initially doubtful value showed useful improvement after reconstructive operation and no secondary nephrectomies were performed. The only death in the series occurred 2 1/2 years postoperatively and was unrelated to the urinary tract.  相似文献   
84.
Two hundred and thirty-five entrants into the MRC trial for mild to moderate hypertension were matched with control subjects in order to assess the psychological effects of a screening programme and recruitment into a clinical trial. The prevalence and incidence of psychiatric morbidity among the trial participants were compared with those of the controls by means of responses to a self-administered questionnaire and diagnostic psychiatric interviews. No differences among the groups were shown between screening and entry into the trial, but after entry the prevalence of psychiatric morbidity among the trial participants fell. This was due to a greater improvement of those with psychiatric symptoms at entry in this group, the incidence of new morbidity being similar among the groups.  相似文献   
85.
Red cell and haemoglobin values in 44 women with a typical picutre of anorexia nervosa showed that 20.5% presented a picture of true anaemia. Blood iron was low, sometimes very low, with a mean value of 66 mg 0/0. Clotting parameters: PTT, TT, PT, circulating platelets and TEG were normal. This finding serves to explain the low incidence of haemorrhage and the ready haemostasis noted in this disease, in spite of the considerable food deficit.  相似文献   
86.
Frank lead ECG's from infants were studied for frequency content by introducing low-pass filters of 50, 75, 100, and 150 150 Hz bandwidths before obtaining computer measurements. Results indicated that a minimum bandwidth of 100 Hz is required to avoid amplitude error of 10 per cent or greater. This bandwidth requierement is essentially the same as that required for adult ECG's despite the fact that infant QRS durations are usually about half those of adults. Although the average infant ECG spectrum is likely to contain higher frequencies than the average adult ECG spectrum, duration values for Q, R, and S waves overlap in these populations to such an extent that bandwidth requirements are practically identical.  相似文献   
87.
In dogs subjected to gravitational overloadings (+Gx) according to a special training schedule the wall structure of the main arteries (carotid, humeral, femoral and aorta) was studied by histological methods. The amount of catecholamines (adrenaline and noradrenaline) in the venous blood plasma and in the adrenal tissue was the index of the sympathoadrenal system condition. It was demonstrated that in trained animals the tolerance threshold to continuously increasing overloadings (+Gx) rose. It was accompanied by an elevated amount of catecholamines in blood and the adrenals In the walls of the main arteries studied a moderate hyperelastosis and a slight collagenization of the adventitia was noted. All parts of the microcirculatory bed were moderately dilated, which favoured a better blood outflow. The data obtained demonstrate adaptational changes, which can be interpreted as indices of training and reliability of the organism.  相似文献   
88.
Massive medial calcific deposits (M?nckeberg's calcinosis) are described in the peripheral and visceral arteries, and similar but small-sized deposits in the coronary arteries of a 41 year old woman with diabetes mellitus. Although observed by roentgenogram fairly commonly during life in the muscular arteries of the legs in middle-aged men, medial calcinosis infrequently involves the visceral arteries and has never, to our knowledge, been documented in the coronary arteries. Although it may be associated with intimal atherosclerosis, medial calcinosis, per se, does not obstruct the lumens of the arteries and, therefore, does not lead to symptoms or signs of limb or organ ischemia. The cause of medial calcinosis remains a mystery, but it appears to affect people with diabetes more frequently than those without.  相似文献   
89.
90.
The dependence on skin temperature of tactile sensitivity to punctiform (hair) stimulation of the finger tip came under study in five subjects. Their data show that punctate sensitivity is relatively stable over a wide range of thermal environments. On the average, some elevation of touch threshold occurred at a skin temperature of 20 degrees C (i.e., about 10 degree below normal), but severe loss of sensitivity first occurred at 10 degrees C. A small but possibly insignificant loss appeared at skin temperatures of 40 and 43 degrees C. The relatively stable behavior of the punctate threshold between about 20 and 40 degrees C contrasts with that of the vibrotactile threshold, which, at least for high frequencies, depends strongly on the skin temperature.  相似文献   
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