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51.
Stimulation of glytamate- and cholinoreceptors by the agonists induced a prolonged calcium and phosphoinositide responses to short-term anoxia or administration of an antioxidant agent in cortical structures. Processes of adaptation essentially modified these responses.  相似文献   
52.
Immune complexes and aggregated IgG (agg-IgG) induce platelet aggregation and the release reaction. Immune complexes also activate the complement system and interact with the complement component C1q. Since platelets possess both Fc and C1q receptors capable of signal transduction, the present study focused on the interaction between these binding sites and platelet activation. Subaggregating doses of agg-IgG (20-400 microg/ml) were identified for washed platelets from each of 11 healthy donors, and platelet aggregation was monitored in the presence or the absence of increasing concentrations of C1q (5-100 microg/ml). C1q produced a dose-dependent potentiation of platelet alphaIIb/beta3 integrin activation, platelet aggregation, and granule secretion when combined with low doses of agg-IgG. C1q alone was without effect. Maximal enhancement of agg-IgG-induced platelet activation was noted at C1q concentrations ranging from 50 to 100 microg/ml. The observed C1q-induced potentiation of platelet aggregation in response to agg-IgG was blocked by polyclonal antibody F(ab')2 directed against platelet binding sites recognizing the collagen-like domain of C1q (cC1qR) or by mAb Fab (IV.3) directed against platelet FcgammaRII receptors. These data suggest a cooperative interaction between platelet FcgammaRII and cC1q receptors and support a potential role for platelet cC1q receptors in pathologic platelet activation by circulating immune complexes often associated with in vivo thrombosis and thrombocytopenia.  相似文献   
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54.
Hemifacial spasm (HFS), generally a disease of the elderly, is caused by vascular compression of the seventh nerve. Vascular compression is thought to result from atherosclerotic changes within the vessels of the posterior fossa, and therefore rarely presents in childhood. Here we describe our experience with 12 patients with onset of HFS during childhood (age 18 or less) and who had surgical exploration of the cerebellopontine angle. These patients represent less than 1.2% of the patient population with HFS operated upon at this institution during the study period. Nine patients had follow-up data extending over 83 months. All 12 patients were found to have microvascular compression of the seventh nerve at the time of surgery. The most common operative finding was compression of the seventh nerve by a vein, alone or in combination with a branch of the anterior inferior cerebellar artery. At the time of discharge and after a mean follow-up period of 125 months, microvascular decompression resulted in complete relief of spasm in 67% of the patients.  相似文献   
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56.
In neonates and infants, hearing impairment leads to impaired language and cognitive development. For that reason, early detection of this sensory deficit is of outstanding importance, particularly in pre-term neonates, who constitute a high risk population in regard to very early acquired hearing loss. Evoked (EOAE) and spontaneous otoacoustic emission (SOAE) recording in 93 pre-term and full-term neonates revealed that this technique is potentially useful for auditory screening in neonatology units. EOAEs and SOAEs can be recorded successfully from 30 weeks of conceptional age. SOAEs were found to be prevalent in females and presented higher peak numbers in right than in left ears. Furthermore, SOAE incidence in pre-term and full-term neonates was found to be high in EOAE positive ears, associated with strong and robust EOAEs.  相似文献   
57.
To study the effectiveness of ACE-inhibitors in diabetic nephropathy (DN) 12 male and 16 female patients aged 13-21 years with DN having normal blood pressure (BP) were given ramipril (tritace) in a dose 2.5-5 mg/day in the course of 12-24 weeks. Efficacy and safety of the treatment were assessed by changes in albuminuria and proteinuria, BP. Reduction of albuminuria occurred in 19(79.1%) out of 24 patients with microalbuminuria, in 13(54.1%) of them urine excretion of albumin returned to normal levels. All the patients with proteinuria and macroalbuminuria benefited from ramipril therapy because their proteinuria diminished or even disappeared (2 cases). The persistence of the antiproteinuria effect on posttreatment week 12 was 66.6%. Ramipril effect on BP was minimal. It is inferred that ramipril is effective in the treatment of DN at the stage of microalbuminuria and proteinuria in patients with normal BP.  相似文献   
58.
Single-phase operation of a three-phase induction generator with the Smith connection (SMIG) is analyzed using the method of symmetrical components. It is shown that, despite the asymmetrical nature of the winding connection, balanced currents can be made to flow in the three-phase stator winding. The conditions for achieving perfect phase balance are carefully deduced. With the aid of a phasor diagram, expressions for the line power factor and line current under perfect phase balance are also obtained. The effect of the phase-balancing capacitances on the generator performance is investigated. A simple dual-mode control scheme is also proposed with a view of minimizing the phase imbalance over the practical operating speed range. Experiments conducted on a 2.2 kW induction machine confirm the validity of the theoretical analysis and feasibility of the control method  相似文献   
59.
A total of 46 pregnant women with premature delivery and preserved amniotic sac were examined. The effect of tocolysis applied was recorded at different control periods of time with the aid of obstetrical monitor. The basic frequency of uterine contractions was more than 3--84.78%. In the 120th min after tocolysis with Partusisten 50% of the cases did not show any labour activity: after 120 min the inhibition was very successful--82.61%. This success was mainly recorded in the cases with uterine contractions over 4 for 10 min (31.61%) followed by those with 3-4 contractions (34.78%) and those with up to 2 uterine contractions (15.22%). On the basis of the results obtained it is concluded that the quicker and earlier the tocolytic was applied, the quicker and lasting was the effect. The statistical analysis revealed that all uterine contractions in the second and particularly in the third group depending on the time of tocolysis gradually passed into the first and second group.  相似文献   
60.
This paper presents a novel mathematical programming approach for the static stability analysis of structures with uncertainties within the framework of FEM. The considered uncertain parameters are material properties, geometry of element cross section, and loading conditions, all of which are described by an interval model. The proposed method formulates the two cases of interest, namely, worst and best buckling load calculation, into a pair of mathematical programming problems. Two straightforward advantages are exhibited by such formulations. The first advantage is that the proposed formulation can overcome the interference on the sharpness of bounds of the buckling load due to the interval dependence issue. The second benefit is that the information of uncertain parameters causing the extremities of buckling load can always be retrieved as by‐products of the uncertain stability analysis. Some numerical examples are presented to illustrate the capability of the proposed method on various structures and the sharpness of the bounds of the buckling load factors. The efficiency and effectiveness of the proposed method are also demonstrated through comparison with the classical Monte Carlo simulation method. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
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