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991.
We evaluated the complement system in 29 children (mean age: 4.5 years) who survived fulminant meningococcal septic shock. No terminal complement deficiencies were found. One patient, who experienced the most dramatic disease course, had a decreased haemolytic activity in the haemolytis-in-gel test for the alternative pathway. The properdin concentration in serum of this patient was < 0.1 g/ml (n = 17.1–27.7 g/ml). Coagulation studies revealed a heterozygeous type I protein C deficiency as well. He was the only patient with aNeisseria meningitidis group Y infection.  相似文献   
992.
A homologous gene transfer system for Aspergillus awamori for site-specific integration is described, based on two components. First, a defined A. awamori pyrG mutant strain constructed by a selection strategy for gene-replacement in fungi. Second, a vector with a homologous pyrG selection marker containing a defined mutation at a site different from that of the mutations in the pyrG gene of the defined mutant strain. Defined mutation in the A. awamori pyrG gene, isolated from a genomic library by heterologous hybridisation with the A. niger pyrG gene as a probe, were introduced by specifically altering sequences at restriction sites in the coding region of the gene. After transformation of the A. awamori wild-type strain with vectors containing these mutated pyrG genes, and selection for 5-fluoro-orotic acid resistance (5-FOAR), on the average 60% of the 5-FOAR colonies originated from replacement of the wild-type pyrG gene by the mutated pyrG allele. After transformation of a mutant strain, carrying a mutation near the 5 end of the pyrG gene with vectors containing a mutation near the 3 end of the pyrG gene, 35% of the resulting transformants contained one copy of the vector at the pyrG locus.  相似文献   
993.
Automated anesthesia recordkeepers have been used to monitor patients during surgery in up to 90% of cases at The Ohio State University. The record-keeping devices are complex and can be difficult to troubleshoot. The 1st-CLASS Fusion Program, an expert system shell-program, has been programmed to allow the resident or nurse anesthetist to solve the two most common types of problems associated with the recordkeeper: printer problems and patient monitor problems. Use of this program allows the resident or nurse anesthetist to troubleshoot the recordkeeper quickly and accurately and promotes in the user a sense of competence and control over the technology.  相似文献   
994.
Summary. The effect of different mental states on autonomic modulation of the cardiovascular system was assessed in healthy, normotensive men (n=18) and women (n=12). Heart rate variability (HRV), systolic blood pressure variability (BPV) and arterial baroreflex function were assessed during 4 tests at rest ((10 min+5 min recovery)×4):
  • 1 Control (spontaneous breathing, (SB)
  • 2 Mental distraction (SB+word puzzle)
  • 3 Conscious control of breathing (paced at SB rate) and
  • 4 Mental stress (SB+computer quiz).
There were no significant gender differences in the responses to the interventions in terms of arterial (spontaneous) baroreflex (SPBX) control of HR, and indices of time and frequency domains of HRV and BPV, with the exception of the sympathetic indicator of HRV (low frequency power/total power; P<0.01) which was lower in women during control and mental stress tests. Conscious control of breathing at SB did not alter HRV, BPV or SPBX in either men or women. Mental distraction and mental stress led to decreases in indices of time and frequency domains of HRV and BPV in all subjects, as well as increases in HR during distraction and in systolic BP during stress. These findings suggest that in studies of cardiovascular control:
  • 1 Paced breathing at SB can be used for individuals with irregular breathing patterns
  • 2 The extent of mental stress achieved is intervention-specific and for the most part, independent of gender and
  • 3 Resting assessment of HRV, BPV and SPBX can be made by having subjects sit quietly without interventions in a controlled laboratory setting.
  相似文献   
995.
Two spontaneous neurodegenerative diseases of the horse, equine motor neuron disease (EMND) and equine degenerative myeloencephalopathy (EDM), have been associated with -tocopherol deficiency, and both were characterized by prominent accumulations of endothelial lipopigment in the small vessels of the spinal cord. These endothelial pigment deposits appear to be reversible. In EMND horses pasture-supplemented for 9 months or more after the progression of weakness and wasting had arrested, there was very little endothelial lipopigment. The origin and the potential effects of these endothelial lipopigment accumulations are discussed.  相似文献   
996.
We evaluated the effect of 2-deoxy-d-glucose (2-DG) on gastric emptying of a non nutrient solution in conscious rats using a Phenol red method. Intravenous injection of 2-deoxy-d-glucose dose-dependently increased the rate of gastric emptying. This stimulatory action of 2-DG was abolished by subdiaphragmatic vagotomy. Intracisternal injection of thyrotropin-releasing hormone (TRH) antibody blocked intracisternal TRH and intravenous 2-DG-induced enhancement of gastric empyting but not the stimulation of gastric emptying induced by intracisternal pancreatic polypeptide. The TRH antibody injected intraperitoneally had no effect. These results suggest that endogenous TRH in the brain is involved in vagal-dependent stimulation of gastric emptying by 2-DG.  相似文献   
997.
Experimental research has recently shown that acupuncture induces the formation of o-pioid-like peptides in animals.The role ofβ-endorphin in the mechanism of acupuncture is discussed:some authors maintain the hormonal hypothesis,others the role of neurotransmltters and,up to thepresent,no convincing evidence for either hypothesis has been demonstrated.In order to provide fur-ther evidence,we tested the β-endorphin levels and other parameters(VLP,lymphocyte subsets,NKcells and phagocyte activity of monocytes)in a group of 90 patients suffering from various painful dis-orders treated with acupuncture.Zusanli(ST 36)and Hegu(LI 4)acupoints were selected.A homo-geneous group of 30 subjects was used as control.Evaluation of the above parameters was made with3 series of blood tests;before treatment,30 minutes and 24 hours after acupuncture treatment.In theacupuncture group,the following results were achieved: a)A considerable increase in β-endorphin levels,which remained high even 24 hours afteracup  相似文献   
998.
The short tandem repeat system FES/FPS was amplified by the polymerase chain reaction (PCR) in 211 unrelated Austrians and analysed by horizontal, non-denaturing electrophoresis. The allele distribution was in Hardy-Weinberg equilibrium. No mutations were found in 25 families (50 meioses). The mean exclusion chance was 0.49, the discriminating power 0.86 and the heterozygosity rate 74.4%. Amplification could be achieved with as little as 100 pg of high molecular weight DNA, which could be reduced to 75 pg by using 32 instead of 30 cycles. By reamplifying 1 l for another 15 cycles, the threshold could be reduced to less than 20 pg. In a degradation experiment DNA extracted from bloodstains stored for up to 24 days in a moist chamber and DNA boiled for up to 18 min could be amplified.  相似文献   
999.
The effect of capsaicin-induced stimulation of afferent neurons on peristalsis and the possible neural mediators involved in this action were examined in the guinea-pig isolated ileum. The intraluminal pressure threshold for eliciting peristaltic waves was used to quantify facilitation (decrease in threshold) or inhibition (increase in threshold) of peristalsis. Capsaicin (0.1–1 M) caused an initial short-lasting stimulation of peristalsis followed by a prolonged inhibition of peristaltic activity. Capsaicin (1 M) was ineffective when the gut segments had been pretreated with 3.3 M capsaicin, which is indicative of an afferent neuron-dependent action of the drug. In contrast, the abolition of peristalsis caused by a high concentration of capsaicin (33 M) was fully reversible on removal and reproducible on readministration of capsaicin, a feature characteristic of a nonspecific depression of smooth muscle excitability. Baseline peristalsis and the excitatory/inhibitory effect of capsaicin (1 M) on peristalsis remained unaltered by a combination of the tachykinin NK1 receptor antagonist ( + )-(2S, 3S)-3-(2-methoxybenzylamino)-2-phenyl piperidine (CP-99,994; 0.3 M) and the tachykinin NK2 receptor antagonist L(-)-N-methyl-N[4-acetylamino-4-phenyl-piperidino-2-(3,4-dichlorophenyl)butyl]-benzamide (SR-48,968; 0.1 M). Further experiments, performed in the presence of a low concentration of atropine (10 nM) showed that the catcitonin gene-related peptide (CGRP) antagonist human -catcitonin gene-related peptide (8–37) [hCGRP (8–37); 10 M] attenuated the delayed inhibitory effect of capsaicin on peristalsis, but did not influence baseline peristaltic activity and the capsaicin-induced facilitation of peristalsis. Blockade of nitric oxide (NO) synthesis by N G-nitro-l-arginine methylester (l-NAME, 300 M) facilitated baseline peristaltic activity and reduced the delayed inhibition of peristalsis caused by capsaicin (1 M) without affecting the initial peristalsis-stimulating action of capsaicin. The effects of l-NAME were prevented by l-arginine (1 mM). The data of the current study indicate that capsaicin-sensitive afferent neurons do not participate in the neural pathways subserving peristalsis in the guinea-pig small intestine, but modulate peristaltic activity upon stimulation with capsaicin. The initial stimulant action of capsaicin on peristalsis is independent of tachykinins acting via NK1 or NK2 receptors, while the delayed capsaicin-induced depression of peristalsis involves CGRP and NO.  相似文献   
1000.
The cerebral representation of space depends on the integration of many different sensory inputs. The vestibular system provides one such input and its dysfunction can cause profound spatial disorientation. Using positron emission tomography (PET), we measured regional cerebral perfusion with various vestibular stimulations to map central vestibular projections and to investigate the cerebral basis of spatial disorientation. We showed that the temporoparietal cortex, the insula, the putamen, and the anterior cingulate cortex are the cerebral projections of the vestibular system in man and that the spatial disorientation caused by unilateral vestibular stimulation is associated with their asymmetric activation.  相似文献   
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