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21.
切开复位内固定治疗股骨髁间骨折 总被引:12,自引:5,他引:7
目的探讨股骨髁间骨折的切开复位内固定临床价值。方法自1995年7月~2001年12月,采用切开复位,普通钢板、95°角钢板、DCS或髁部支撑钢板等内固定治疗股骨髁间骨折32例。根据AO/ASIF分类,C1型13例,C2型10例,C3型9例。根据术前术后X线片及术后膝关节功能恢复情况评价内固定效果。结果27例获得随访,随访时间9个月~7年,根据Sanders评分标准,优14例,良9例,差4例。结论切开复位内固定是治疗股骨髁间骨折的理想选择。 相似文献
22.
R B Banati D Hoppe K Gottmann G W Kreutzberg H Kettenmann 《Journal of neuroscience research》1991,30(4):593-600
Rat microglia share a number of antigenic, functional, and morphological similarities with macrophages from other tissues, but are characterized by a distinctly different pattern of ion channels in the cellular membrane (Kettenmann et al., J Neurosci Res 26:278-287, 1990). Macrophages typically express outward and inward K+ currents. In contrast, microglia lack outward currents and only show inwardly rectifying K+ currents, regardless of the isolation or cultivation method employed for microglia. In this study we demonstrate that a subpopulation of bone marrow-derived macrophage-like cells possesses inward rectifier K+ currents, but no outward currents and thus with regard to the electrophysiological characteristics closely resembles microglia. A second population of bone marrow-derived macrophage-like cells shows the usual channel pattern described for other body macrophages. Our results strengthen the hypothesis that in the bone marrow distinct pools of precursor cells exist, possibly reflecting an early differential lineage determination for body and brain macrophages, i.e., microglia. 相似文献
23.
目的探讨工程菌表达的耐热DNA聚合酶的纯化方法。②方法收集IPTG诱导带有耐热DNA聚合酶(TD聚合酶)基因表达质粒的工程菌株DH-TD4,用溶菌酶裂解,60℃处理后,上清液用硫酸铵沉淀,根据溶解度差异进行粗分级,然后进行离子交换层析细分级,并经聚合酶链式反应(PCR扩增)鉴定其活性。③结果纯化的TD聚合酶具有良好的聚合活性。④结论溶解度差异与离子交换层析是工程菌表达的耐热DNA聚合酶纯化的主要步骤。基因工程制备的DNA聚合酶可用于PCR检测 相似文献
24.
W. Walz A. F. Allen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,68(2):290-298
Summary Homogenous primary cultures of mouse astrocytes and cortical neurons were used to clarify the role of taurine in ion and osmoregulation in the CNS. This study indicates that both neurons and glial cells have uptake systems for taurine. The cell water content does not change during loading of cells with taurine. Chemical analysis indicates that part of the accumulated taurine is metabolized and that the product(s) are stored in the cells. Extracellular taurine (1 mM) has no effect on K+, Na+, Cl-, or Ca2+ movements in astrocytes. However, astrocytes loaded to a taurine content which corresponds a concentration of 60 mM (corresponds to normal mouse cortex levels) show a 50% reduction in their K+ accumulation by carriers and a 100% increase in Ca2+ turnover rates. Movements of Ca2+ and K+ are involved in neurotransmission. It appears that taurine stored in glial cells, has an important effect on ion homeostasis in the CNS and may act indirectly on neuronal excitability. 相似文献
25.
Previous studies have shown that prostaglandin D2 (PGD2) inhibits neuronally mediated secretion in the rat colon. This antisecretory action of PGD2 was further characterized by the use of a prostaglandin D receptor blocker. Prostaglandin D2 inhibited the neuronally mediated short-circuit current evoked by prostaglandin I2, which represents Cl- secretion. The concentration-response curve for the inhibition by PGD2 was shifted to the right in the presence of the prostaglandin D receptor blocker, AH 6809. AH 6809 had no effect on the short-circuit current response induced by prostaglandin E2 or iloprost, a stable prostaglandin I2 analogue, suggesting an interaction of the blocker with receptors specific for PGD2. A direct interaction of PGD2 with enteric neurones was studied by determining its effect on acetylcholine release from enteric neurones preloaded with [3H]choline. Prostaglandin D2 suppressed 3H release induced by electric field stimulation. It had, however, no effect on the release induced by depolarization with potassium. The results suggest that the inhibitory action of PGD2 on enteric cholinergic neurones is mediated by prostaglandin D receptors. 相似文献
26.
D. Dory C. Chopin I. Aimone-Gastin J. L. Gueant L. Guerin J. Sainte-Laudy D. A. Moneret-Vautrin J. Fleurence 《Allergy》1998,53(1):42-50
Allergy to fish is one of the most common food allergies. Gad c 1 is the only fish allergen which has been purified and characterized. Other allergens have been detected by Western blot in cod extracts. We have now improved the Western-blot procedure in order to characterize fish IgE-reactive proteins from extracts prepared under different conditions: pre-rigor mortis and postrigor mortis. EDTA addition or not. and DEAE ion-exchange chromatography. Several IgE-reactive protein bands have been identified over a wide molecular-weight range. In particular, the 104- and 130-kDa IgEreactive protein bands were detected. These new bands may correspond to aggregates, as EDTA increased the relative amount of the 60-, 67-, 104-, and 130-kDa IgE-reactive protein bands in Western blot. All these bands were also detected by an antiparvalbumin monoclonal antibody, specific to the first calcium-binding site. The longer period of storage increased the relative amounts of the 41-, 80-, 104-. and 130-kDa IgE-reactive protein bands. The 18-kDa band was detected only in fish stored for several days. In conclusion, we have described IgE-reactive protein bands over a wide molecular-weight range (12–130 kDa) in Western blot of cod extract, and shown that EDTA and storage conditions may influence the relative distribution of IgE-reactive protein bands. 相似文献
27.
Shear stress induced membrane currents and calcium transients in human vascular endothelial cells 总被引:3,自引:0,他引:3
Gero Schwarz Guy Droogmans Bernd Nilius 《Pflügers Archiv : European journal of physiology》1992,421(4):394-396
We have measured membrane currents induced by shear stress together with intracellular calcium signals in endothelial cells from human umbilical cord veins. In the presence of extracellular calcium (Ca2+]o), shear stress induced an inward current at a holding potential of 0 mV which is accompanied by a rise in intracellular Ca2+ ([Ca2+]i). In the absence of extracellular calcium shear stress was unable to evoke a calcium signal but still induced a membrane current. The voltage dependence of the shear stress induced current was obtained from difference currents evoked by linear voltage ramps before and during application of shear stress. Its reversal potential Erev shifted from –2.3±0.8 mV (n=4) in a nominally Ca2+ free solution to +1.5±1.6 mV at 1.5 mM [Ca2+]o (n=4) and to +21.9±4.4 mV (n=7) at 10 mM [Ca2+]o. From our data we conclude that shear stress opens an ion channel that is 12.5±2.9 (n=7) times more permeable for calcium than for sodium or cesium. 相似文献
28.
Muscle relaxant action of excitatory amino acid antagonists 总被引:2,自引:0,他引:2
L Turski M Schwarz W A Turski T Klockgether K H Sontag J F Collins 《Neuroscience letters》1985,53(3):321-326
Antagonists of neuronal excitation induced by dicarboxylic amino acids were tested in genetically spastic rats of the Han-Wistar strain. These animals exhibit an increased muscle tone which can be measured as a spontaneous tonic activity in the electromyogram of the gastrocnemius-soleus muscle. Compounds that block excitation due to N-methyl-D-aspartic acid reduced the spontaneous activity measured in the electromyogram in a dose-related manner. The most potent compounds, 2-amino-7-phosphonoheptanoic and kynurenic acids were effective muscle relaxants when given either intraperitoneally or intracerebroventricularly. 2-Amino-5-phosphonopentanoic acid possessed much weaker muscle relaxant activity, while L-glutamic acid diethylester was inactive by either route. The results suggest that blockade of N-methyl-D-aspartic acid receptors results in a myorelaxant effect. Specific antagonists of excitation at N-methyl-D-aspartic acid receptors may provide a new class of muscle relaxants. 相似文献
29.
30.
Xun Wang Rongzuo Xu Grant Abernathey Jordan Taylor M B Alzghoul Kevin Hannon Gregory H Hockerman Amber L Pond 《Developmental dynamics》2008,237(9):2430-2437
The Kv11.1 (also ERG1) K(+) channel underlies cardiac I(Kr), a current that contributes to repolarization in mammalian heart. In mice, I(Kr) current density decreases with development and studies suggest that changes in the structure and/or properties of the heteromultimeric I(Kr)/Kv11.1 channel are responsible. Here, using immunohistochemistry, we report that total Kv11.1 alpha subunit protein is more abundant in neonatal heart and is distributed throughout both adult and neonatal ventricles with greater abundance in epicardia. Immunoblots reveal that the alpha subunit alternative splice variant, Kv11.1a, is more abundant in adult heart while the Kv11.1b variant is more abundant in neonatal heart. Additionally, MinK channel subunit protein is shown to co-assemble with Kv11.1 protein and is more abundant in neonatal heart. In summary, Kv11.1/I(Kr) channel composition varies developmentally and the higher I(Kr) current density in neonatal heart is likely attributable to higher abundance of Kv11.1/I(Kr) channels, more specifically, the Kv11.1b splice variant. 相似文献