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101.
α-细辛脑对气管纤毛运动的影响 总被引:44,自引:0,他引:44
目的:研究α-细辛脑对气管纤毛运动的影响,探讨其祛痰作用机理。方法:采用鸽子在体气管和家兔离体气管试验:设空白、阳性对照组及α-细辛脑高、中、低剂理组,以墨汁走距和运行速度作为气管纤毛运动指标,各试验组与空白对照组进行t检验。比较其组间差异。结果:给浅度麻醉的鸽子静脉注射α-细辛脑32mg/kg、16mg/kg、8mg/kg,墨汁走距分别为(1.17±0.12)cm,(1.15±0.17)cm和( 相似文献
102.
目的 :研究 Opalescence脱色方法对色素牙脱色的疗效。方法 :将 Opalescence脱色剂涂于个别托模唇、颊侧内 ,病人每晚睡前刷牙后擦干牙面 ,戴上托模 ,晨起摘下冲洗干净 ,每天 1次 ,疗程一般为 2周 ,视疗效及患者反应增减用药时间。结果 :1 1 2例患者脱色治疗后氟斑牙的显效率( 80 .8%)高于四环素牙的显效率 ( 66.7%)。有 2 3例病人疗效不甚满意。结论 :应用 Opalescence脱色治疗活髓色素牙效果明显 ,脱色后牙体呈自然色泽 ,透明感好 ,特别适用于年龄较轻、无牙体缺损的氟斑牙及四环素牙的脱色。 相似文献
103.
Radiology of the orbital apex 总被引:1,自引:0,他引:1
The orbital apex, formed by the superior orbital fissure and optic canal, is the cross-road between the orbit and the intracranial structures. Pathological processes may extend intracranially via the superior orbital fissure and vice versa. In addition to intrinsic soft tissue lesions, various pathological processes may involve the surrounding osseous anatomy. Malignant lesions arising from adjacent structures or from haematogeneous metastasis may also infiltrate this region. 相似文献
104.
PURPOSE: To investigate a case of isolated pedunculated congenital corneal dermoid. METHODS: Case report. RESULTS: In a 14-day-old infant, the pedunculated portion of the dermoid was removed and confirmed by histopathologic examination. No surgical complication or recurrence was encountered, and the patient is waiting for a rotational autokeratoplasty. CONCLUSIONS: Prompt treatment of such an unusual tumor is important to allow for visual rehabilitation and development. 相似文献
105.
Ascorbate, often used as an antioxidant in neural studies, may also serve as a neuromodulator in the vertebrate central nervous system (CNS), in that it modulates the synaptic actions of glutamate and dopamine. Retina of fish contain a high concentration of ascorbate. The release and/or uptake of neurotransmitters are related to membrane potential, which to a large extent is determined by the activity of K+ channels. As retinal bipolar cells are subject to synaptic input from glutamatergic and dopaminergic sources, the effects of ascorbate on voltage-dependent K+ currents (I(K)(v)) of the mixed rod-cone ON-center bipolar cells (Mb) in goldfish retinal slices were studied using whole-cell recording techniques. I(K)(V) was suppressed reversibly 60% by 100-200 microM ascorbate. The effect of ascorbate was not due to changes in pH, oxidative stress, lipid peroxidation, any Ca2+-dependent or Na+-dependent action. However, the suppressive effect of ascorbate was blocked by cholera toxin and Wiptide, a protein kinase A (PKA) inhibitor. It is concluded that ascorbate, at physiological concentrations, inhibits I(K)(V) of bipolar cells via a Gs-protein-PKA system. This effect of ascorbate should be taken into account when using ascorbate as an antioxidant in retinal studies involving dopamine. 相似文献
106.
目的 观察氯地滴眼液对家兔眼压及房角组织影响。方法 用60只家兔设实验和对照组,以含0.175%氯霉素和0.15%地塞米松的氯地跟液滴眼,每日4次,生理盐水对照。于1/2、1、2、3月测眼压后处死家兔以电镜观察房角组织变化。结果 眼压和房角组织结构与对照组无明显差异。结论 临床应用氯地眼液3月内是安全的。 相似文献
107.
目的: 评价准分子激光屈光性角膜切削术治疗放射状角膜切开术后残余近视散光的预测性、稳定性和安全性。方法: 对52 眼 R K 术后残余近视散光患者行再次 P R K 治疗, 并连续随访两年以上。术前残余球镜屈光度- 375±132 D,残余柱镜屈光度- 236±125 D, 最佳矫正视力均≥08。结果: 术后 6 个月球镜屈光度- 032±024 D, 柱镜屈光度- 078±052 D, 裸眼视力≥10 者46 眼 (8846% ), 术后 24 个月球镜屈光度- 037±042 D, 柱镜屈光度- 056±037 D, 裸眼视力≥10 者 42 眼 (8076% )。最佳矫正视力下降 1 行以上者 3 眼 (576% ), 实际球镜矫正度与预期矫正度相差10 D 以内 50 眼 (9015% ), 柱镜相差 10 D以内51 眼 (9807% )。结论: P R K 治疗 R K 术后残余近视散光的两年随访结果表明, 该方法预测性强、稳定性好和安全性高, 特别在矫正残余散光方面, 其结果令人满意。 相似文献
108.
左旋四氢巴马汀对单个豚鼠心室肌细胞钙电流的阻滞作用 总被引:4,自引:0,他引:4
AIM: To study the effect of l-tetrahydropalmatine (l-THP) on L-type calcium channel. METHODS: Patch clamp technique (whole cell recording) was used to record L-Ca2+ current in single cardiac myocyte. RESULTS: 1) l-THP 1, 10, and 100 micromol.L-1 reduced ICa-max from (999 +/- 93) pA to (700 +/- 111) pA, (582 +/- 66) pA, and (420 +/- 112) pA (n = 6, P < 0.01), respectively. 2) l-THP reduced the voltage at half-maximal inactivation (V1/2) of L-Ca2+ channel to more negative potentials by 9 mV (n = 5, P < 0.05). 3) l-THP caused both tonic and use-dependent reduction of Ca2+ current. Tonic block of l-THP on Ca2+ current was 46% +/- 8% (n = 6, P < 0.01). The degree of use dependent blocking was 13.5% +/- 2.4% (n = 6, P < 0.05) at 1 Hz, the degree increased to 44% +/- 5% (n = 6, P < 0.01) at 3 Hz. 4) l-THP delayed half-recovery time of Ca2+ channel recovery from inactivity from (94 +/- 39) ms to (170 +/- 42) ms(n = 6, P < 0.01). CONCLUSION: l-THP has a moderate inhibitory effect on L-Ca2+ current. 相似文献
109.
To test the hypothesis that the cytokines interleukin-6 (IL-6) and IL-8 may play regulatory roles in the aberrant neovascularization in chronic inflammatory diseases, we examined their effects in a rat sponge model and compared their actions with those of IL-1 and lumor necrosis factor- (TNF-). Daily doses of 3 pmol IL-8, IL-1, TNF-, but nol IL-6, significantly accelerated the sponge-induced angio-genesis. Although lower doses (0.3 pmol) of these cytokines were inactive, IL-1 acted synergistically with subthreshold daily doses (10 pmol) of substance P (SP) and bradykinin (BK) to produce an intense angiogenic response. In contrast, IL-8 only interacted positively with IL-1, but not TNF-, SP, or BK. There was no synergism or antagonism between IL-6 and SP. These results demonstrate the discrete interactions between angiogenic factors and cytokines in chronic inflammation and suggest that the sponge model is a good means for the study of such interactions. 相似文献
110.
Shuzhi Yang Lingxiang Li Jun Han Haiyan Chen Wei Zhang Erzhong Fan Ying Li 《临床耳鼻咽喉头颈外科杂志》2003,17(6):336-338
OBJECTIVE: To explore the expression of TGF-beta 1/T beta R II in laryngeal carcinoma. METHOD: Immunohistochemical study using SP kit in 53 cases. RESULT: The expression of TGF-beta 1 was decreased in carcinoma tissues when compared with peri-cancer controls (P < 0.05). There wasn't difference in T beta R II expression when compared with peri cancer controls (P > 0.05). But it was correlated with the stage, differentiation and lymph node metastasis of laryngeal carcinoma. CONCLUSION: TGF-beta 1/T beta R II may involve in the histogenesis and development of laryngeal carcinoma. The decreased expression of TGF-beta 1/T beta R II may serve as an important molecular marker of laryngeal carcinoma. 相似文献