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991.
V P Petlenko 《Vestnik khirurgii imeni I. I. Grekova》1986,136(2):3-7
The article elucidates the importance of ideological grounding of physicians and methods of ideological education. Critics of bourgeois theories on the relationship of science and ideology is given. 相似文献
992.
E Jansson V Bomfim M Grynfarb L Kaijser 《Scandinavian journal of thoracic and cardiovascular surgery》1986,20(2):137-140
Myocardial energy metabolism during hypothermic potassium cardioplegia with blood as the cardioplegia vehicle, given in one or two bolus doses, was studied in eight patients undergoing aortic valve replacement. Myocardial biopsies were taken from the left ventricle 10 min after aortic cross-clamping (a.c.) and immediately before declamping (d.c.) and were analyzed for ATP, creatine phosphate (CP), creatine (C) and lactate. The interindividual range of myocardial temperature was 11-19 degrees C at 10 min a.c. and 11-25 degrees C immediately before d.c. The myocardial ATP concentration fell (17.2 +/- 5.7-12.8 +/- 2.8 mmol X kg-1 dry muscle), the lactate concentration rose (64.7 +/- 35.8-136 +/- 33.8 mmol X kg-1 d.m.) and the total creatine pool (CP + C) was unchanged. Hypothermic blood cardioplegia conferred fairly good initial protection of the myocardium, but the reduction in ATP and the great lactate accumulation towards the end of cardioplegia, especially in patients with myocardial temperature reaching 19-25 degrees C, indicates that such protection is adequate only if the myocardial temperature is maintained between 11 and 18 degrees C. 相似文献
993.
Relations between basal ganglia and hippocampus: action of substantia nigra and pallidum 总被引:1,自引:0,他引:1
M Sabatino V La Grutta G Ferraro G La Grutta 《Revue d'électroencéphalographie et de neurophysiologie clinique》1986,16(2):179-190
Several interrelationships exist between basal ganglia and hippocampus. The ventral striatum appears to be involved in the control of the dopaminergic nigro-striatal pathway. The caudate, in turn, seems to influence the hippocampal theta rhythm and to inhibit hippocampal spikes. In the present work the role played by globus pallidus pars interna and substantia nigra pars compacta on hippocampal bioelectrical activity is studied. Injection of sodium penicillin i.v. produces steady interictal spikes in the hippocampus. Substantia nigra stimulation induces regular theta rhythm and inhibits the spikes. Pallidal stimulation, on the contrary, appears to strongly enhance epileptiform activity, proceeding to generalised seizure activity. The results are discussed in the light of a putative feedback loop from basal ganglia to hippocampus, probably underlying co-participation of the two subcortical structures in the control of motor behaviour. 相似文献
994.
The diffusion of a series of non steroidal antiinflammatory drugs through a silicone rubber membrane has been studied from suspensions both of the free and beta-cyclodextrin complexes forms at different pH values of the medium. Higher diffusion rates of the complexed forms as compared with the free ones and a rate-limiting effect of the apparent stability constant in the diffusion of the complexes were observed. 相似文献
995.
Muscarinic suppression of the M-current in the rat sympathetic ganglion is mediated by receptors of the M1-subtype. 总被引:6,自引:1,他引:5 下载免费PDF全文
N. V. Marrion T. G. Smart S. J. Marsh D. A. Brown 《British journal of pharmacology》1989,98(2):557-573
1. Under voltage-clamp dissociated adult and foetal rat superior cervical ganglion (s.c.g.) cells exhibited a non-inactivating voltage- and time-dependent component of K+ current termed the M-current (IM). IM was detected and measured from the current decay during hyperpolarizing voltage steps applied from potentials where IM was pre-activated. 2. Neither the resting membrane current nor the amplitude of these current decay relaxations were reduced by omitting Ca from the bathing fluid, showing that the M-current was not a 'Ca-activated' K-current dependent on a primary Ca-influx. Concentrations of (+)-tubocurarine sufficient to block the slow Ca-activated K-current IAHP did not inhibit IM or antagonize the effect of muscarinic agonists on IM, showing that IM was not contaminated by IAHP. Tetraethylammonium (1 mM), which blocks the fast Ca-activated K-current IC, produced a small inhibition of IM. This was not due to contamination of IM by IC since muscarinic agonists did not consistently block IC. 3. The muscarinic agonists muscarine, oxotremorine, McN-A-343 and methacholine reversibly suppressed IM, resulting in an inward (depolarizing) current. The rank order of potency was: oxotremorine greater than or equal to muscarine greater than McN-A-343 greater than methacholine. 4. The suppression of IM by muscarine was similar in cultured cells derived from adult and foetal tissue to that seen in the intact ganglia. 5. IM-suppression by muscarine was inhibited by pirenzepine (Pz) and AF-DX 116 with mean pKB values of 7.53 +/- 0.13 (n = 3) and 6.02 +/- 0.13 (n = 4) respectively. 6. The suppression of IM by muscarinic agonists was not affected by gallamine (10-30 microM). 4-Diphenylacetoxy-N-methylpiperidine methiodide inhibited the response at 300 nM. 7. Pirenzepine inhibited the contractions of the guinea-pig isolated ileum produced by muscarine with a mean pKB of 6.37 +/- 0.03 (n = 8). 8. These results suggest that the receptors mediating suppression of the M-current accord with those designated pharmacologically as M1 and that these receptors reach maturity at a very early stage in the development of the rat s.c.g. 相似文献
996.
997.
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1000.
L. Ostrosky-Zeichner C. Sable J. Sobel B. D. Alexander G. Donowitz V. Kan C. A. Kauffman D. Kett R. A. Larsen V. Morrison M. Nucci P. G. Pappas M. E. Bradley S. Major L. Zimmer D. Wallace W. E. Dismukes J. H. Rex 《European journal of clinical microbiology & infectious diseases》2007,26(4):271-276
The study presented here was performed in order to create a rule that identifies subjects at high risk for invasive candidiasis
in the intensive care setting. Retrospective review and statistical modelling were carried out on 2,890 patients who stayed
at least 4 days in nine hospitals in the USA and Brazil; the overall incidence of invasive candidiasis in this group was 3%
(88 cases). The best performing rule was as follows: Any systemic antibiotic (days 1–3) OR presence of a central venous catheter
(days 1–3) AND at least TWO of the following—total parenteral nutrition (days 1–3), any dialysis (days 1–3), any major surgery
(days −7–0), pancreatitis (days −7–0), any use of steroids (days −7–3), or use of other immunosuppressive agents (days −7–0).
The rate of invasive candidiasis among patients meeting the rule was 9.9%, capturing 34% of cases in the units, with the following
performance: relative risk 4.36, sensitivity 0.34, specificity 0.90, positive predictive value 0.01, and negative predictive
value 0.97. The rule may identify patients at high risk of invasive candidiasis.
Results of this project were partially presented at Focus on Fungal Infections 14, New Orleans, LA, USA, 2004. Abstract no.
51. 相似文献