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991.
The aim of this study was to test the hypothesis that post-exercise hypotension was the mechanism for the plasma volume and albumin gain during recovery. Seven healthy young men completed two experiments (> or =1 week apart) to exercise continuously at 65% of peak aerobic capacity for 60 min followed by the recovery without (experiment 1) or with phenylephrine infusion (experiment 2) to counteract post-exercise hypotension. Heart rate, arterial pressure (Finapres), plasma volume (PV, Evans blue dye dilution), haematocrit, haemoglobin, plasma total solutes (refractometer), albumin, total proteins (colorimetric method), [Na+] and [K+] were not different prior to the experiments. Exercise decreased PV -13.7% (-521 mL) and -14.2% (-566 mL) at the end of 60 min in experiments 1 and 2, respectively, associated with increases in the concentrations of plasma albumin, total protein and solutes. These changes were similar between the two experiments. Following 30 min recovery in experiment 1 the decreased PV was not significantly different from the baseline. Although the volume restoration was complete at the end of 90 min recovery, the change in the albumin concentration was still above zero, indicating a gain of 11 g albumin (P < 0.05). When phenylephrine was infused during recovery, there was no gain in intravascular albumin associated with a sustained decrease in PV (-7% or -280 mL, P < 0.05) observed at the end of experiment 2. These data suggest that post-exercise hypotension may be the mechanism for a gain of intravascular albumin via the lymph return, which enhances plasma water retention and PV restoration during recovery from exercise induced hypovolaemia, even without rehydration. 相似文献
992.
Effects of intracolonic opioid receptor agonists on polymodal pelvic nerve afferent fibers in the rat 总被引:1,自引:0,他引:1
We studied the effects of intracolonic administration of opioid receptor agonists (ORAs) on responses of pelvic nerve afferent fibers to colorectal distension (CRD) and heat. Single-fiber recordings were made from the decentralized S1 dorsal rootlet in the rat. An approximately 7-cm length of descending colon was isolated in situ to permit intracolonic perfusion with Krebs solution, which, when the outflow was clamped, was used to distend the colon. Responses to noxious CRD (40 mmHg, 30 s) were tested after intracolonic instillation of mu-, delta- or kappa-ORAs. Intracolonic administration of the kappa-ORAs EMD 61,753 (n = 5/12) and U62,066 (n = 8/11), but not either the mu-ORA fentanyl or the delta-ORA SNC-80, concentration-dependently inhibited responses of afferent fibers. For fibers unaffected by intracolonic administration of EMD 61,753 or U62,066, intra-arterial administration of kappa-ORAs was effective. Forty-one of 54 mechanosensitive fibers also responded to intracolonic instillation of heated Krebs solution (50 degrees C). Intra-arterial injection of fentanyl or SNC-80 did not attenuate responses to heat. Either intracolonic or intra-arterial administration of EMD 61,753 or U62, 066, however, inhibited afferent fiber responses to heat. These results document that mechanical and thermal sensitivity of polymodal pelvic nerve afferent fibers innervating the rat colon can be inhibited peripherally by intracolonic instillation of kappa-ORAs. 相似文献
993.
Saulquin X Ibisch C Peyrat MA Scotet E Hourmant M Vie H Bonneville M Houssaint E 《European journal of immunology》2000,30(9):2531-2539
Knowledge of the immunodominant responses to Epstein-Barr Virus (EBV) and human cytomegalovirus (HCMV) should help to generate cytotoxic T cell lines to these herpesviruses. Here we report on the analysis of CD8 T cell responses to EBV and HCMV in the blood of kidney transplant recipients undergoing viral reactivation (n = 16) and in healthy virus carriers (n = 10). We used a transient COS transfection assay that permits semi-quantitative estimation of CD8+ T cell responses against a larger number of HLA/viral protein combinations within polyclonal T cell lines and thus allows a rapid identification of major epitopes. From the comparison of these responses to those that we previously described in the synovial fluid of patients suffering from various forms of chronic arthritis (n = 32), it appears that EBV-specific T cells are mainly directed against a restricted set of immunodominant epitopes, primarily generated during the early lytic cycle and that both IE1 and pp65 are targets of the anti-HCMV response. We suggest that this method could be generally applied to the rapid identification of immunodominant T cell epitopes in viral and tumor immunity, and could help selecting HLA-peptide complexes that could be used to detect and sort specific T cell populations. 相似文献
994.
C. Crouzet H. Fournier X. Papon N. Hentati P. Cronier Ph. Mercier 《Surgical and radiologic anatomy : SRA》1998,20(4):273-278
Summary The findings from 12 dissections of previously injected facial masks, 8 dissections of the face following intrarterial injection of a red solution of Latex Neoprene, and a corrosion cast specimen allowed us to study the arterial supply of the lips. The arterial supply of the upper lip arises mainly from the superior labial arteries, but also from the subseptal arteries and from the subalar arteries. There is a figure of 8 shaped anastomotic system between these arteries lying on the upper lip. The arterial supply of the lower lip arises from the inferior labial arteries and from branches of the mental artery. A constant inferior labial arterial network was shown at the level of the lower lip arising in a fifth of cases from a T-shaped inferior labial artery. All these recent anatomic findings help us to improve our understanding of plastic surgery of the lips.
Vascularisation artérielle des lèvres
Résumé Douze dissections de masques faciaux préalablement injectés à la gélatine minium, huit dissections de face après injection artérielle par une solution de latex néoprène rouge, et une injectioncorrosion a permis l'étude de la vascularisation artérielle labiale. La lèvre supérieure reçoit sa vascularisation artérielle des artères labiales supérieures principalement, mais aussi des artères sous-narinaires branches des artères faciales, et des artères de la sous-cloison. Il existe un système d'anastomose fréquent entre les trois artères décrivant un aspect de 8 de chiffre couché au niveau de la lèvre supérieure. La lèvre inférieure est vascularisée par les artères labiales inférieures et par des branches de l'artère mentonnière ; il existe de manière constante au niveau de la lèvre inférieure une arche artérielle labiale inférieure provenant une fois sur cinq d'une artère labiales inférieure en T unique. Toute ces données anatomiques récentes permettent d'envisager dans de meilleures conditions la chirurgie réparatrice des lèvres.相似文献
995.
Genome sequence of tick-borne encephalitis virus (Western subtype) and comparative analysis of nonstructural proteins with other flaviviruses 总被引:13,自引:0,他引:13
The genome sequence of tick-borne encephalitis (TBE) virus (Western subtype vaccine strain Neudoerfl) was determined. This extends the previously published sequence of the structural proteins to the nonstructural protein region and noncoding sequences at the 5'- and 3'-termini. The amino-termini of the individual proteins were assigned by comparison with other flavivirus sequences. Amino acid homology calculations between TBE virus and mosquito-borne flaviviruses were performed for all nonstructural proteins. An evolutionary tree based on protein NS1 is presented that reveals the molecular basis of relationships among flaviviruses. Tick-borne and mosquito-borne flaviviruses share a common hydrophilicity profile and also other features of their primary sequences, such as the presumably functional Gly-Asp-Asp sequence element within protein NS5. Other characteristics, such as the potential N-glycosylation sites of protein NS1 and a potential proteolytic cleavage site within protein NS4B, are conserved within the mosquito-borne group, but differ in the TBE virus sequence. 相似文献
996.
Effects of protein supplementation during prolonged exercise at moderate altitude on performance and plasma amino acid pattern 总被引:2,自引:0,他引:2
A. X. Bigard P. Satabin P. Lavier F. Canon D. Taillandier C. Y. Guezennec 《European journal of applied physiology》1993,66(1):5-10
Summary The effects of two levels of protein intake on muscle performance and energy metabolism were studied in humans submitted to repeated daily sessions of prolonged exercise at moderate altitude. For this purpose, 29 healthy males, were exposed to seven successive stages of ski-mountaineering at altitudes between 2500 and 3 800 m, and to an isocaloric diet (4000 kcal·day–1, 16760 kJ·day–1) with either 1.5g·kg–1·day–1 (C group,n =14), or 2.5 g·kg–1·day–1 (PR group,n =15) protein intake. Measurements made after the ski-mountaineering programme did not show any change in body mass. The peak torque during maximal isometric voluntary contraction (MVC) of the quadriceps muscle was unaffected by the repeated exercises, whereas the endurance time at 50% MVC was decreased in PR subjects (–26.8%,P<0.001). Increased levels of both free fatty acids (+147%,P<0.001) and glycerol (+170%,P<0.001) observed in C subjects would suggest that lipolysis was enhanced after the repeated exercise. The plasma amino acid pattern was altered after completion of the ski-mountaineering programme; the plasma concentration of the three branched-chain amino acids (BCAA) was significantly decreased in C subjects, whereas the higher level of protein intake (PR group) greatly minimized the exercise-induced decrease in serum BCAA. 相似文献
997.
998.
背景:近年来,随着全膝关节置换技术提升、手术时间缩短、术中及术后止血药的应用,其总失血量不断减少,术后引流量也逐渐减少,术后快速康复理论应运而生,引流管放置也再次成为骨科医生所热议的问题,越来越多的医生认为可以常规取消放置引流,引流似乎已可有可无。目的:旨在复习既往文献,对全膝关节置换后引流放置的相关问题归纳总结,提供围术期引流管理的相关经验。方法:检索中国知网、万方、维普、中国生物医学文献数据库等中文数据库,以及PubMed、The Cochrane Library、WebofScience、EMBASE、OVID等外文数据库,以"引流,膝关节置换术"及"totalknee arthroplasty,drainage"为检索词,检索自建库始至2020年2月为止所有与主题相关的文献,总结归纳全膝关节置换后不放置引流管围术期各方面需综合考虑的要素。结果与结论:①引流管的放置问题关乎全膝关节置换手术的最终结果,与术后出血、血肿、血栓、感染等并发症的发生关系密切;②目前全膝关节置换术后不推荐常规放置引流,但不意味着不需要管理,其实际上对临床医护在围术期各方面的管理提出更高的要求,包括但不限于术前适应证选择、手术操作、止血带使用、术中及术后药物使用、物理疗法的使用等。 相似文献
999.
B. Denis A. Lefort R. M. Flipo F. Tubach M. Lemann P. Ravaud D. Salmon X. Mariette O. Lortholary 《Clinical microbiology and infection》2008,14(2):183-186
This study investigated the long-term outcome of patients with tuberculosis (TB) as a complication of tumour necrosis factor (TNF)-α blocker therapy. All TB cases ( n = 21) complicating TNF-α blocker therapy from French university hospitals were collated between January 2000 and September 2002. Outcome was assessed via a postal questionnaire during September 2005. The mortality rate after 4 years was 4.8%, and one patient had relapsed and six (29%) patients had recommenced TNF-α antagonist treatment, after appropriate anti-TB therapy, without reactivation. These data support the concept that TNF-α antagonists can be restarted in TB patients provided that adequate anti-TB treatment has been completed. 相似文献
1000.
B Denis A Lefort R M Flipo F Tubach M Lemann P Ravaud D Salmon X Mariette O Lortholary 《Clinical microbiology and infection》2008,14(2):183-186
This study investigated the long-term outcome of patients with tuberculosis (TB) as a complication of tumour necrosis factor (TNF)-alpha blocker therapy. All TB cases (n = 21) complicating TNF-alpha blocker therapy from French university hospitals were collated between January 2000 and September 2002. Outcome was assessed via a postal questionnaire during September 2005. The mortality rate after 4 years was 4.8%, and one patient had relapsed and six (29%) patients had recommenced TNF-alpha antagonist treatment, after appropriate anti-TB therapy, without reactivation. These data support the concept that TNF-alpha antagonists can be restarted in TB patients provided that adequate anti-TB treatment has been completed. 相似文献