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41.
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M A MacLean R Wilson J A Thomson S Krishnamurthy J J Walker 《European journal of obstetrics, gynecology, and reproductive biology》1992,43(3):167-172
During pregnancy the mother must tolerate intra-uterine allogenic fetal tissue. Failure of this tolerance may cause spontaneous abortion. The immunological changes occurring in normal pregnancy are poorly understood. The aim of this study was to investigate the immunological changes occurring in pregnancy. Thirty women in the first trimester; 10 in the second and 10 in the third trimester of pregnancy were studied and compared to age matched non-pregnant controls. In normal pregnancy there was an increase in the total white cell count with no change in the lymphocyte count. There was a fall in total T cell numbers and activated T cell numbers, with no change in helper/inducer or suppressor/cytotoxic T cell numbers. [3H]Thymidine uptake in response to three different mitogens was increased. This implies an increase in potential for the cells to respond to mitogens. There was no change in interleukin-2 receptor levels, suggesting that despite this increased potential there was no general activation of the immune system. A rise in IgM and IgG was found after mitogen stimulation of peripheral blood lymphocytes, suggesting an increase in potential antibody production. These results demonstrate that lymphocytes from pregnant women have an increased potential rather than an increased activity. 相似文献
43.
The aim of this study was to carry out quantitative analyses of eye movements during the cover test on a group ( n = 57) of asymptomatic emmetropes. Eye movements were recorded during an automated cover test while subjects fixated a distance (3.4 m) and near (0.4 m) target. There was a significant difference between the amplitude of phoria measured after 2 s of occlusion compared to 10 s ( P < 0.01). The mean phoria after 10 s of occlusion was 0.1° (eso) for distance fixation and 1.6° (exo) for near fixation. The distribution was approximately normal for both distance and near fixation but the standard deviation was greater for near (2.0°) than distance fixation (1.4°). The pattern of eye movements during the recovery phase was more complex than is often assumed, in many cases consisting of a variety of saccadic and vergence movements involving both the covered and 'fixing' eye. The latency of the first recovery movement was significantly shorter for exophoric than esophoric deviations ( P < 0.01) and the latency of some recovery movements were very short (< 150 ms). 相似文献
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The intra-operative histological assessment of fresh tissue can provide valuable diagnostic information and guide surgical
management, however, even a limited exposure to standard fixation agents can potentially compromise analysis. Defined handling
strategies should exist to facilitate the receipt of all specimens, in their optimal state, by the laboratory. 相似文献
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1. Repeated aerosolization of leukotriene C4 (LTC4) to guinea-pigs produced leftward shift in their pulmonary resistance (RL) dose-response curves to inhaled acetylcholine (ACh) without increasing the maximum responses. 2. Repeated LTC4 aerosolization did not increase airway eosinophils. 3. The 5-lipoxygenase-activating protein (FLAP) inhibitor, MK-886, prevented the leftward shift in RL dose-response curves to ACh following repeated antigen challenge in guinea-pigs. 4. MK-886 did not inhibit the increased maximal RL produced by repeated antigen challenge, nor inhibit the airway eosinophilia induced by repeated antigen challenge. 5. Our findings suggest that leukotrienes may account for the leftward shift in pulmonary resistance responses caused by antigen but do not cause the airway eosinophilia nor enhanced maximum broncho-constrictor response to antigen. 相似文献
50.
Piper I. R.; Garrioch M. A.; Souter M. J.; Andrews PJD.; Thomson D. 《British journal of anaesthesia》1998,80(5):639-643
Diaspirin cross-linked haemoglobin (DCLHb) is a new oxygen carrying blood
substitute with vasoactive properties. Vasoactive properties may be
mediated via high affinity binding of nitric oxide by the haem moiety.
Using a rodent model of head injury combined with ischaemia, we studied the
effects of DCLHb on cerebral blood flow (CBF) and intracranial pressure
(ICP). Twenty anaesthetized rats were allocated randomly to receive
treatment with DCLHb 400 mg kg-1 i.v. or placebo (oncotically matched
plasma protein substitute 4.5% i.v.). To produce diffusely increased ICP,
after a severe weight drop injury, all animals underwent a 30-min period of
bilateral carotid ligation combined with a period of induced hypotension.
After reperfusion, DCLHb or placebo was infused and the animals
instrumented for measurement of intraventricular ICP and CBF in the region
of the sensorimotor cortex using the hydrogen clearance technique. Mean
arterial pressure (MAP), ICP, cerebral perfusion pressure (CPP) (CPP = MAP
- ICP) and CBF were measured 4 h after injury in all animals. DCLHb
significantly reduced ICP from mean 13 (SEM 2) to 3 (1) mm Hg (P <
0.001), increased CPP from 52 (8) to 95 (6) mm Hg (P < 0.001) and
increased CBF from 21 (2) to 29 (2) ml 100 g-1 min-1 (P = 0.032). We
conclude that DCLHb improved CPP without a reduction in CBF in a rodent
model of post-traumatic brain swelling.
相似文献