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1.
2.
Isolated pure dislocations of the fifth carpo-metacarpal joint are extremely rare injuries. The dorsal form was described
in mere 12 cases. The diagnosis can be easily missed. The lesion is also often overlooked in the routine diagnostic X-ray.
Lateral and oblique views are important for the recognition of the true extent of the lesion. Treatment of these injures is
still controversial and both closed reduction with percutaneous pinning or open reduction with internal fixation are advocated.
The goal of treatment is early reduction and fixation of the metacarpal. Early diagnosis is the key to success. The aim of
this paper is to review literature and present two new cases. 相似文献
3.
Vascular hyperpermeability is a cardinal feature of inflammation or bum in which an array of inflammatory mediators can cause such changes in the microvessels. The fimctional measures of microvascular exchange that represent the properties of microvascular wails are the permeability coefficients which have been reported from measurements on intact whole organisms (including human subjects}, on perfused tissues and organs, on single perfused microvessels, and on monolayers of cultured microvascular endothelial cells. In this review, we summarize some experiments of vascular permeability in individually isolated perfused microvessels. 相似文献
4.
F. Tribut B. Lapied A. Duval M. Pelhate 《Pflügers Archiv : European journal of physiology》1991,419(6):665-667
Short-term culture of isolated adult dorsal unpaired median (DUM) neurons of the cockroach Periplaneta americana has been used to study the evolution of the sodium current during the time in culture after axotomy and deafferentation treatment. An increase in the maximum peak amplitude of the sodium current recorded under voltage-clamp conditions with the patch-clamp technique in the whole-cell recording configuration, was only observed between 24h and 72h (75%) without any modification of the kinetics and the voltage-dependence of the current. A decrease in the level of foetal calf serum in the culture medium reduces the amplitude of the sodium current on all days but does not affect its time-course of development which was on the contrary completely abolished by both protein synthesis inhibitors, actinomycin D and cycloheximide. The results obtained in these neurons strongly suggest that a neosynthesis of sodium channel proteins is involved in the evolution of the sodium current induced by axotomy and deafferentation. 相似文献
5.
Abstract: The effects of pyridoxalated hemoglobin polyoxyethylene conjugate (PHP) and stroma-free hemoglobin (SFH) on vascular responsiveness to various vasoactive substances were examined in isolated perfused rat kidneys. The kidneys isolated from rats were perfused with 6% PHP, 6% SFH, and 6% hydroxyethylstarch (HES) solution at a constant flow rate. Vascular responsiveness to acetylcholine (ACh), nitroglycerin (NG), norepinephrine (NE), and angiotensin-II (ANG-II) was examined by measuring the perfusion pressure (PP). Effects of inhibition of endothelium-derived relaxing factor (EDRF) by NG -monomethyl L-arginine (L-NMMA) on NE-induced and ANG-II-induced renal vascular responses were examined. ACh and NG induced a dose-dependent decrease in perfusion pressure (PP) in all groups. NE and ANG-II induced an increase in PP in all groups, but NE-induced and ANG-II-induced responses in the PHP-perfused and SFH-perfused groups were significantly larger than those in the HES-perfused group. L-NMMA did not alter vascular responsiveness to NE and ANG-II. These results indicate that PHP and SFH do not inhibit EDRF induced by ACh, but hemoglobin moiety per se does augment the vascular responsiveness to NE and ANG-II in the isolated perfused rat kidney. 相似文献
6.
在体肺隔离高温灌注的实验研究 总被引:1,自引:0,他引:1
8条犬于左肺动脉及左房分别插入灌注管及引流管后阻断,使左肺隔离。肝素化预充液中加入超量阿霉素进行常温及高温(41~43℃)的灌注转流。监测肺水含量、肺顺应性、血气、肺动脉压、肺实质温度、鼻咽温、血液学等指标,并行病理检查。结果表明:单侧肺隔离高温灌注在手术方法与转流技术上是可行的;它提供的热源简便,温度理想。高温灌注化疗对肺组织有一定影响,但其程度可逆;临床应用是可行的。 相似文献
7.
目的:观察地塞米松对冷藏离体肺表面活性物质和顺应性的影响.方法:32只家兔肺随机均分为对照组、地塞米松冷藏(4℃)保存24h、72h、120h3个组.对照组:测定室温条件下的肺表面活性物质及顺应性.冷藏组:肺离体后立即置于含有地塞米松台式液中冷藏,在相应时间取出肺,室温条件下复温后,置入生理盐水中,测定肺表面活性物质,并测定注气(生理盐水)和抽气(生理盐水)过程中,肺容积在10ml、20ml、30ml时的肺顺应性.结果:冷藏24h组注水、抽水;72h组肺容积在10ml、20ml抽气、冷藏120h组在肺容积为10ml、20ml抽气的肺顺应性同对照组比较,差异无显著性(P>0.05).其余各组、项与对照组比较差异具有显著性(P<0.05),伴有表面活性物质的减少.结论:地塞米松冷藏离体肺顺应性增大,其影响程度随冷藏时间的延长而增加,同时伴有肺表面活性物质的减少. 相似文献
8.
Jeffrey F. Waring Rita Ciurlionis Robert A. Jolly Matthew Heindel Gerry Gagne Jane A. Fagerland Roger G. Ulrich 《Toxicology in vitro》2003,17(5-6):693-701
In vitro human hepatocyte cultures are a key tool in the investigation of xenobiotic toxicity and metabolism. In most in vitro hepatocyte studies, the cells are allowed to adhere to an extracellular matrix, such as collagen. Unfortunately, the ability of freshly isolated hepatocytes to adhere to collagen varies from donor to donor. We used microarray analysis to determine what gene expression differences exist between hepatocytes in suspension and hepatocytes attached to collagen. Results from different donors showed a considerable difference in gene expression patterns between the two hepatocyte populations. In addition, we also compared the gene expression profiles of hepatocytes in culture with liver tissue. The results showed that both hepatocytes in suspension and hepatocytes attached to collagen display significant gene expression differences compared with liver tissue. Finally, we show that both populations of hepatocytes are responsive to dexamethasone and regulate some of the same genes. Overall, our results suggest that either significant gene expression changes occur in isolated hepatocytes or that suspended and attached cells represent different populations of hepatocytes found in intact livers. 相似文献
9.
Isolated noncompaction of the ventricular myocardium 总被引:6,自引:0,他引:6
Isolated noncompaction of the ventricular myocardium is a recently described anomaly. We report the first case of this anomaly
presenting as a restrictive cardiomyopathy, and the first association of this entity with endocardial fibrosis. 相似文献
10.
Summary A single glass micropipette voltage clamp technique with intracellular dialysis was used to study the effects of the trapidil derivatives AR 12–456 and AR 12–463 on Ca channel currents carried by Bat+ in isolated ventricular cells from mice hearts. Inspite of a more potent inhibition of the cAMP phosphodiesterase from heart (Bartel et al. 1985) a reversible Ca channel blocking action of both compounds could be observed. The concentration of half maximal block was calculated to about 50 mol/l for both derivatives tested. Neither a shift in the current-voltage relationships nor a significant change in the potential for half maximal activation was found. The maximal Ba2+ -conductance was reduced. The steady state inactivation was shifted towards more negative potentials by application of 100 mol/l AR 12–463. The decay of the Ba currents was accelerated in the range of the applied test potentials between –20 and +20 mV. It is concluded that the new trapidil derivatives with more potent inhibitory action on cardiac phosphodiesterase than trapidil can block myocardial Ca channels.
Send offprint requests to B. Nilius 相似文献