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93.
荆芥连翘汤对促进皮肤溃疡愈合的影响 总被引:4,自引:0,他引:4
目的 观察荆芥连翘汤对小鼠皮肤溃疡的治疗作用。方法 建立小鼠皮肤创伤和烫伤两种皮肤溃疡模型.比较荆芥连翘汤以及rhEGF的用药组和自身对照组小鼠皮肤溃疡面积,用昆微镜观察溃疡面炎症细胞浸润情况。结果 和自身对照组相比,荆芥连翘汤可明显缩小小鼠皮肤溃疡面积(P〈0.001),同时炎症细胞浸润显著减少(P〈0.001);荆芥连翘汤用药组疗效显著优于rhEGF用药组。结论 荆芥连翘汤可明显促进小鼠皮肤溃疡的愈合。 相似文献
94.
目的探讨三根祛瘤方(简称三根方)对结肠癌细胞的作用机制。方法:采用不同浓度的三根方处理结肠癌SW480细胞后,以四唑盐比色试验检测细胞增殖,以westernblot检测环氧化酶-2蛋白水平,采用凝胶迁移率法检测核因子-κB活性。结果:三根方对结肠癌SW480细胞增殖具有较强的抑制作用。三根方能抑制环氧化酶-2蛋白水平的表达及抑制核因子-κB活性,且呈浓度依赖性。结论:三根方能够抑制结肠癌细胞的恶性增殖,其机制与抑制环氧化酶-2基因的表达及核因子-κB活性有关。 相似文献
95.
Effects of plantago-mucilage A (P-MA) on the immune responses were studied in ICR mice. Mice were divided into 4 groups (10 mice/group), and P-MA at doses of 7, 21 and 63 mg/kg were orally administered to mice once a day for 21 consecutive days. Mice were immunized and challenged with sheep red blood cells (SRBC). P-MA at 63 mg/kg/day significantly increased the body weight gain and the relative weights of spleen and thymus, as compared with those in controls. However, there were no significant effects on liver weight due to P-MA treatment. Plaque forming cells (PFC) and hemagglutination (HA) titers to SRBC were significantly enhanced in mice dosed at 21 and 63 mg/kg/day P-MA, as compared with those in controls. Delayed-type hypersensitivity (DTH) reaction to SRBC, phagocyte activity and circulating leukocyte were also significantly increased in mice dosed at 63 mg/kg/day P-MA. These results demonstrate that P-MA markedly enhances both humoral immune and allergic reaction to SRBC at concentrations which don’t act on the relative weight of liver. 相似文献
96.
Blocking effects of polyunsaturated fatty acids on Na+ channels of neonatal rat ventricular myocytes. 总被引:11,自引:3,他引:8
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Y F Xiao J X Kang J P Morgan A Leaf 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(24):11000-11004
Recent evidence indicates that polyunsaturated long-chain fatty acids (PUFAs) prevent lethal ischemia-induced cardiac arrhythmias in animals and probably in humans. To increase understanding of the mechanism(s) of this phenomenon, the effects of PUFAs on Na+ currents were assessed by the whole-cell patch-clamp technique in cultured neonatal rat ventricular myocytes. Extracellular application of the free 5,8,11,14,17-eicosapentaenoic acid (EPA) produced a concentration-dependent suppression of ventricular, voltage-activated Na+ currents (INa). After cardiac myocytes were treated with 5 or 10 microM EPA, the peak INa (elicited by a single-step voltage change with pulses from -80 to -30 mV) was decreased by 51% +/- 8% (P < 0.01; n = 10) and 64% +/- 5% (P < 0.001; n = 21), respectively, within 2 min. Likewise, the same concentrations of 4,7,10,16,19-docosahexaenoic acid produced the same inhibition of INa. By contrast, 5 and 10 microM arachidonic acid (AA) caused less inhibition of INa, but both n - 6 and n - 3 PUFAs inhibited INa significantly. A monounsaturated fatty acid and a saturated fatty acid did not. After washing out EPA, INa returned to the control level. Raising the concentration of EPA to 40 microM completely blocked INa. The IC50 of EPA was 4.8 microM. The inhibition of this Na+ channel was found to be dose and time, but not use dependent. Also, the EPA-induced inhibition of INa was voltage dependent, since 10 microM EPA produced 83% +/- 7% and 29% +/- 5% inhibition of INa elicited by pulses from -80 to -30 mV and from -150 to -30 mV, respectively, in single-step voltage changes. A concentration of 10 microM EPA shifted the steady-state inactivation curve of INa by -19 +/- 3 mV (n = 7; P < 0.01). These effects of PUFAs on INa may be important for their antiarrhythmic effect in vivo. 相似文献
97.
Xin-ping Tang Kang Zeng Guan-hua Chen Long-yan Bi Long-zhong Fan Chang-fa Shao 《第一军医大学学报》2003,23(8):870-872
OBJECTIVE: To investigate the association of Malassezia furfur with chronic urticaria in the crew members of ships. METHODS: A comparative mycological study of 126 crew members of ships with chronic urticaria and 45 normal control subjects was carried out. The 82 urticaria patients identified as positive for Malassezia furfur were divided into groups A and B to receive treatment with antihistaminics (group A) and antihistaminics combined with 2% ketoconazole shampoo(group A). RESULTS: The carrier rates of Malassezia furfur were significantly higher in urticaria patients than in the normal control subjects (P<0.01), but in view of the case ratios of the final cure or improvement, no significant difference was observed between the two groups by the end of the treatment courses (P>0.05). But 6 to 8 weeks from the end of the treatment course, better therapeutic effect was noted in group B (P<0.01), with higher rate of negative Malassezia furfur findings (P<0.01). CONCLUSION: Malassezia furfur may play an important role in the prevalence of chronic urticaria among the crew members, and anti-fungal treatment may produce better long-term therapeutic effect. 相似文献
98.
Excitation and desensitization of mouse rod photoreceptors in vivo following bright adapting light 总被引:3,自引:1,他引:2
Jennifer J. Kang Derwent Nasser M. Qtaishat David R. Pepperberg 《The Journal of physiology》2002,541(1):201-218
Electroretinographic (ERG) methods were used to determine response properties of mouse rod photoreceptors in vivo following adapting illumination that produced a significant extent of rhodopsin bleaching. Bleaching levels prevailing at ∼10 min and ∼20 min after the adapting exposure were on average 14% and 9%, respectively, based on the analysis of visual cycle retinoids in the eye tissues. Recovery of the rod response to the adapting light was monitored by analysing the ERG a -wave response to a bright probe flash presented at varying times during dark adaptation. A paired-flash procedure, in which the probe flash was presented at defined times after a weak test flash of fixed strength, was used to determine sensitivity of the rod response to the test flash. Recovery of the response to the adapting light was 80% complete at 13.5 ± 3.0 min (mean ± s.d .; n = 7) after adapting light offset. The adapting light caused prolonged desensitization of the weak-flash response derived from paired-flash data. By comparison with results obtained in the absence of the adapting exposure, desensitization determined with a test-probe interval of 80 ms was ∼fourfold after 5 min of dark adaptation and ∼twofold after 20 min. The results indicate, for mouse rods in vivo , that the time scale for recovery of weak-flash sensitivity substantially exceeds that for the recovery of circulating current following significant rhodopsin bleaching. The lingering desensitization may reflect a reduced efficiency of signal transmission in the phototransduction cascade distinct from that due to residual excitation. 相似文献
99.
Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model. 相似文献
100.
Simple measurement of spinal cord evoked potential: a valuable data source in the rat spinal cord injury model. 总被引:1,自引:0,他引:1
Jong-Pil Park Ki-Jeong Kim Ji Hoon Phi Chul-Kee Park Jong-Hoon Kim Hyo Jin Kang Dohun Lee Kyu Hyun Han Kyu-Chang Wang Sun Ha Paek 《Journal of clinical neuroscience》2007,14(11):1099-1105
Measurement of spinal cord evoked potentials (SCEPs) is proposed as a means of predicting locomotion outcome in the rat spinal cord injury (SCI) model. Using 55 rats, three reproducible peak waves (waves I, II and III) were observed during stimulation at the C7 level with recording at the L1 epidural space. Hemisection at the T13 level showed three wave loss patterns: wave III loss only, loss of both wave II and III, and loss of all three waves. Defining an ideal SCI model as establishment of stable monoparesis or paraparesis, all animals in the wave II-III loss group showed favorable results. Histological data and electrophysiological properties allowed reasonable assumptions of wave origin: wave I from extrapyramidal tracts, wave II from the ventral corticospinal tract, and wave III from the dorsal corticospinal tract. Complete destruction of pyramidal tracts in both dorsal and ventral fibers was essential for long-term impairment of locomotion. 相似文献