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991.
The plasma levels of several haemostatic and fibrinolytic parameters were measured before and after delivery in 61 hypertensive pregnant women of whom 22 developed preeclampsia, and compared to the results obtained in 42 normal pregnant women. In the two last weeks before delivery (D less than or equal to -15) tPA antigen, PAI-1 activity, vWF:Ag/FVIII:C ratio, ATIII activity and platelet count were found to be significantly different in the hypertensive pregnant women with and without preeclampsia. Combined all together, an association of three of these five parameters were found to be pathological (i.e.:tPA:Ag greater than or equal to 19 ng/ml, PAI-1 activity greater than or equal to 58 IU/ml, vWF:Ag/FVIII:C ratio greater than or equal to 2.6, ATIII activity less than or equal to 73%) in none of the hypertensive women without preeclampsia and in only 35% of the preeclamptic group. A positive correlation was demonstrated between vWF:Ag/FVIII:C ratio and tPA:antigen levels suggesting that both tPA and vWF:Ag could be considered as early indicators of a possible micro angiopathy occurring in preeclampsia. However, due to the high dispersion of the results, it appears that the investigated haemostatic and/or fibrinolytic criteria give only presumptive arguments before assigning risk for preeclampsia development among hypertensive pregnant women.  相似文献   
992.
993.
994.
Plasma tumor necrosis factor and mortality in critically ill septic patients   总被引:23,自引:0,他引:23  
Tumor necrosis factor (TNF) cachectin has been implicated as an important host mediator responsible for shock and multiple organ failure (MOF) observed during sepsis. Using a sensitive enzyme-linked immunosorbent assay, we measured plasma TNF levels in 43 septic patients suffering from a broad range of diseases. Measurements were taken on the day that sepsis was diagnosed. Eleven patients had detectable TNF plasma levels ranging from 10 to 100 pg/ml (TNF-positive group); in 32 patients circulating TNF could not be detected (TNF-negative group). The groups did not differ significantly as to age, underlying disease, percentage positive bacteremia and bacteriologic profile, sepsis score, and extent of MOF. Eight (73%) of 11 TNF-positive patients died from sepsis during ICU stay, vs. 11 (34%) of 32 TNF-negative patients (p less than .05). This study demonstrates that sepsis is accompanied by detectable circulating TNF in 25% of the cases, and for these patients mortality is twice that for comparable TNF-negative patients.  相似文献   
995.
B R Wang  E Senba  M Tohyama 《Neuroscience》1989,28(3):711-723
Studies were made on whether substance P-, leucine-enkephalin- and 5-hydroxytryptamine (serotonin)-like immunoreactive fibers exert a direct influence on the cremaster motoneurons of the male rat by immunocytochemistry combined with retrograde tracing at the light- and electron-microscopic levels. Horseradish peroxidase was used as a retrograde tracer. Two days after injection of horseradish peroxidase into the genitofemoral nerves, its accumulation in the cremaster motoneurons was demonstrated by the diaminobenzidine-nickel method. On immunocytochemical examination of the same sections immunoreactive end-products were detected by the peroxidase-antiperoxidase method. Two different kinds of reaction products were distinguishable at both the light- and electron-microscopical levels. The horseradish peroxidase-labeled cremaster motoneurons at the L1 and L2 levels of the spinal cord were surrounded by abundant immunoreactive terminals. Examination at the ultrastructural level showed that substance P-like immunoreactive terminals formed synaptic contacts almost exclusively with the proximal dendrites of these horseradish peroxidase-labeled cremaster motoneurons. On the other hand, in the leucine-enkephalin- and serotonin-like boutons, significant numbers of axosomatic contacts with horseradish peroxidase-labeled cells were seen although axodendritic contacts with horseradish peroxidase-labeled cells were predominant. Occasionally, leucine-enkephalin-like immunoreactive fibers with synapses on horseradish peroxidase-labeled neurons formed axoaxonic contacts with other leucine-enkephalin-like axonal terminals. Thus, substance P-, leucine-enkephalin- and serotonin-like fibers clearly regulate the function of cremaster motoneurons monosynaptically. The varied synaptic contacts of these fibers according to the neuroactive substances involved suggest different actions of these substances on the cremaster motoneurons.  相似文献   
996.
The alkylating agent ifosfamide synthesized according to own method at the Institute of Pharmaceutical Industry, Warsaw, was compared in biological evaluations with Holoxan (Asta-Werke's ifosfamide). No significant differences between tested compounds were found in respect of acute toxicity and antitumor activity in experimental systems in mice.  相似文献   
997.
998.
A fluid-fiber-collagen stress tensor is used to describe the rheology of the left ventricle of the heart. Linear theory is used to find the equilibrium solutions for the end-diastolic and end-systolic states of general axisymmetric shapes that are small perturbations of a thick-walled finite cylinder. The general problem can be studied by superposing the effects of variable midwall radius but constant wall thickness with those of variable wall thickness but constant midwall radius. A Fourier series representation is used to describe the midwall radius and thickness functions. Numerical calculations are performed to determine the deformed geometry and spatial distributions of tissue pressure, stresses, and fiber strains. The calculations proved to be highly accurate when compared to an analytical solution obtained for the special case of no fibers. The results show significant longitudinal differences when compared to results for the cylindrical geometry, with more sensitivity to variation in wall thickness than to variation in midwall radius.  相似文献   
999.
A review of 96 consecutive patients who suffered neuro-ophthalmologic injuries in motorcycle accidents revealed a wide range of findings. These findings were similar to signs associated with other forms of closed-head trauma, aside from a higher incidence of trochlear nerve palsies.  相似文献   
1000.
An experiment was carried out to investigate the effect of a range of estradiol (E2) doses (0.1-6.5 micrograms/g body wt/day) on vitamin D metabolism and the plasma levels of growth hormone (GH) and prolactin (PRL) in the growing chick. Doses of 0.5-0.7 microgram/g E2, which are insufficient to raise the plasma calcium level, did induce an increase in growth rate, an increase in 25-hydroxyvitamin D 1 alpha-hydroxylase (1-hydroxylase) and 24-hydroxylase activities, and an increase in plasma GH level. These parameters leveled off or fell over the dose range 1-2 micrograms/g E2 but there was evidence of a second peak in 1-hydroxylase activity at 6 micrograms/g E2. At this high dose rate, the plasma Ca level rose to 8 mM, as it does in the laying hen; 24-hydroxylase activity, growth rate, and plasma GH and plasma PRL levels all decreased. It was concluded that the dose response to estrogen in the growing chick is not linear and, in the case of 1-hydroxylase activity, may even be biphasic.  相似文献   
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