大鼠背根节内两类兴奋性神经元的放电特征

目的:观察大鼠背根节(DRG)神经元兴奋性分类的放电特征.方法:在新鲜分散的中、小型大鼠背根节神经元运用全细胞膜片钳技术,观察给予胞内去极化,超极化电流刺激引起细胞放电的特征.结果:根据大鼠背根节神经元的放电特征可将它们区分为两类兴奋性.1类:神经元兴奋性与刺激强度相关,逐渐增强的去极化刺激可引发频率由低到高的动作电位.一般于超极化刺激后不产生反跳动作电位.动作电位的幅值一致,符合"全或无"定律.2类:神经元的兴奋性与去极化刺激强度关系不明显,神经元放电频率比较稳定,不随刺激强度的增强而增加,放电前后有规律的膜电位振荡.于较弱的超极化刺激后可产生反跳动作电位.动作电位的幅值不一致.结论:大鼠DRG两类兴奋性神经元各具不同的放电特征.     

乌头碱对受损背根节神经元自发放电的作用

目的：研究钠通道失活门抑制剂乌头碱(aconitine)对受损背根节(DRG)神经元不同模式的背景放电的作用．方法：在大鼠DRG慢性压迫模型上记录A类单纤维自发放电,观察和分析乌头碱作用下动作电位峰峰间期序列(isi)的变化及特征．结果：在大鼠L5DRG浸浴乌头碱(10～200μmol／L)后,80％簇放电(bursting)和70％不规则放电(irregular)逐渐转化为持续的周期放电;91％周期放电(period)只表现为放电频率的不断增加,并没有发生放电模式的转化．对于静息的神经元,乌头碱则不能引发放电．结论：在阻断钠通道失活门之后,受损DRG神经元的自发放电可以发生模式转化,并且乌头碱对DRG神经元的作用具有活动依赖性．     

丙戊酸钠对大鼠损伤背根节神经元异位自发放电的抑制作用

目的: 探讨丙戊酸钠(sodium valproate, VPA)对损伤背根节神经元异位自发放电的影响及其时间和剂量关系. 方法: 分离背根单纤维,引导来自损伤背根节(dorsal root ganglion, DRG)神经元的异位自发放电,观察不同浓度VPA对放电频率和放电模式的影响. 结果: VPA可抑制异位自发放电,降低其放电数,并具有剂量依赖关系. 结论: 局部应用VPA可抑制DRG神经元自发放电,这可为外周应用VPA进行镇痛治疗提供依据.     

低频刺激抑制GABA介导背根神经节神经元膜去极化反应

目的:探讨低频率电刺激对GABA介导的背根神经节神经元膜电位去极化反应的影响.方法:新鲜分离的大鼠DRG坐骨神经干标本,通过细胞内微电极记录技术,应用波宽5 ms,强度2 V,频率分别为2 Hz和10 Hz的脉冲波作用于大鼠坐骨神经远端,观察刺激前后GABA(3×10-4mol/L)介导的DRG神经元膜电位去极化反应幅值的变化.结果:低频电刺激(2 Hz、10 Hz)对GABA介导的DRG神经元膜电位去极化反应均有抑制作用,10 Hz时抑制作用达到最大,反应幅值从17.00±3.39mV降至12.00±2.45mV(P<0.05).刺激频率增加,电刺激对GABA介导DRG神经元膜去极化反应抑制作用持续时间也逐渐延长,10 Hz时作用持续时间达到最长(>72 min).结论:电刺激可抑制DRG神经元膜GABA去极化反应,从而易化伤害性信息的传入,导致疼痛.     

混沌和周期的交感神经刺激对大鼠受损背根节神经元放电的影响

目的研究受损背根节(DRG)神经元对不同时间序列的交感神经刺激反应。方法采用单纤维记录神经元自发放电的方法,在DRG慢性压迫模型上,电刺激腰交感神经干,比较受损DRG神经元对周期和混沌的交感神经刺激的反应。结果慢性压迫DRG中存在交感-感觉耦联现象。受损DRG神经元对交感神经刺激的反应随刺激频率(在5~20 Hz范围内)的增加而增大(P<0.01)。将刺激平均频率和刺激强度相同而刺激时间序列不同的交感神经刺激引起受损DRG神经元的反应进行比较发现,混沌的交感神经刺激引起的反应比周期的交感神经刺激引起的反应大(P<0.01)。结论除刺激频率外,交感神经刺激的时间序列是影响受损DRG神经元反应的重要因素,混沌刺激引起的效应比周期刺激效应强,突触前神经元的混沌放电比周期放电可引起更大的突触后效应,神经元的混沌放电可能是神经传递信息的一种有效形式。     

A型肉毒毒素对大鼠受损背根节神经元放电和交感-感觉耦联的影响

目的 研究A型肉毒毒素(BTXA)对慢性压迫背根节(DRG)神经元(慢性神经痛模型)的自发放电和交感-感觉耦联的影响.方法 采用单纤维记录神经元自发放电的方法,在受损DRG上加BTXA,观察BTXA对DRG神经元自发放电的影响.电刺激腰交感神经干,观察交感刺激对受损DRG神经元放电的调节作用,静脉注射BTXA后,再观察交感刺激对受损DRG神经元放电的影响.结果 慢性压迫DRG神经元有丰富的自发放电,47个受损DRG神经元放电对无钙人工脑脊液有显著的兴奋反应,但BTXA对这些神经元的自发放电无影响.64%的受损DRG神经元对腰交感神经干电刺激有反应,交感刺激对受损DRG的这种作用可被静脉注射BTXA所阻断.结论 BTXA对慢性压迫DRG神经元的自发放电无影响.在慢性压迫DRG神经元上存在交感-感觉耦联现象,BTXA可以阻断这种交感-感觉耦联现象.     

辣椒素通过钙信号抑制感觉神经元的电压门控性钙离子通道

目的 研究辣椒素对大鼠背根神经节神经元的电压门控性钙离子通道的抑制效应及其信号机制.方法 在急性分离的大鼠背根神经节(DRG)神经元上,应用全细胞膜片钳技术记录电压激活性钙离子通道电流以及辣椒素诱导的电流,应用钙离子成像技术检测Ca2+浓度的变化.结果 辣椒素能够抑制大鼠DRG神经元的电压激活性钙离子通道电流.细胞外钾离子浓度显著升高引起细胞去极化并打开膜上电压门控性钙离子通道引起胞外Ca2+内流,辣椒素只在引起胞内Ca2+浓度显著升高的情况下才能抑制高钾诱导的电压门控性Ca2+内流.用咖啡因耗竭细胞内Ryanodine敏感性钙库以后,辣椒素引发的胞内钙浓度升高的效应被显著抑制,说明辣椒素可诱导胞内Ryanodine敏感性钙库释放Ca2+.结论 在辣椒素敏感性的大鼠DRG神经元中,辣椒索通过胞内钙信号抑制电压门控性钙离子通道.Ca2+信号部分来源于Ryanodine敏感性钙库.     

受损背根节神经元持续性钠流的检测

目的:检测损伤大鼠背根节(DRG)神经元持续性钠流(persistent sodium current, Inap)并研究其与阈下膜电位振荡的关系. 方法: 术后3～6 d慢性痛大鼠模型背根节急性分离,消化离散成单细胞,对中小型DRG神经元运用全细胞膜片钳技术记录. 结果: 电压钳下,钳制电位在-80 mV,给予斜波去极化到-30 mV时,细胞产生一持续时间150～200 ms,幅值89～200 pA的持续性内向钠流,且对100 nmol/L TTX敏感.电流钳下,产生阈下膜电位振荡的细胞,给予100 nmol/L TTX后,振荡消失.结论:在受损DRG神经元上检测到的持续性钠流可能是产生阈下膜电位振荡的基础之一.     

乙酰胆碱对大鼠慢性压迫背根节神经元放电的影响

目的研究乙酰胆碱(ACh)对大鼠慢性压迫背根节(DRG)神经元放电的影响。方法采用单纤维记录神经元自发放电的方法,在DRG慢性压迫模型上观察ACh对受损DRG神经元自发放电的影响。结果受损DRG神经元有丰富的自发放电,77.9%有自发放电的受损DRG神经元对ACh有反应,其中反应类型有单纯兴奋和先兴奋后抑制两种形式,而且反应的幅度随ACh浓度的延长而逐渐增大。结论在慢性压迫DRG神经元有大量的自发放电,ACh可明显影响受损DRG神经元的自发放电。     

受损背根节神经元对高浓度钙反应的敏感性与其放电型式的关系

目的　研究受损背根节 (DRG)神经元的放电型式与其对高浓度钙 (Ca2 + )反应敏感性的关系 .方法　在大鼠慢性压迫 DRG模型上记录单纤维的自发放电 ,比较具有周期和非周期放电型式的神经元对 Ca2 +反应敏感性 .结果 2 1%的周期放电神经元和 83%的非周期放电神经元对 Ca2 + (5 mmol·L- 1 )有反应 (P<0 .0 1) .非周期放电神经元对不同浓度 Ca2 +的反应均比周期放电神经元大 (P<0 .0 1) .将对 Ca2 + 无反应的周期放电神经元转化为非周期放电后 ,对同一浓度的 Ca2 +出现明显的反应 .结论　非周期放电神经元比周期放电神经元对高钙反应敏感 .     

Value of D-Dimers in patients with acute aortic dissection

Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P ＜ 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (＞0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P ＜0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P ＜ 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.     

Research of combined liver-kidney transplantation model in rats

Objective： To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods： SD rats served as both donors and recipients. 4℃ sodium lactate Ringer＇s was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava （IVC） inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results： Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion： This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.     

BLOOD PRESSURE CHANGE WITH AGE IN SALT-SENSITIVE TEENAGERS

Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P＜ 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P＜ 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.     

安心颗粒对急诊经皮冠状动脉介入术后生活质量影响的研究

目的：评价使用安心颗粒对急诊经皮冠状动脉介入术（PPCI）术后生活质量的影响.方法：将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组（术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次）和对照组（仅接受基础药物治疗）.所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表（MIDAS）、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果：入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异（P＞0.05）;出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低（P＜0.05）;组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低（P＜0.05）.两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血（P＞0.05）.两组发生轻度血小板减少症的患者数比较无差异（P＞0.05）.结论：PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.     

The comparative studies of the influences of Urapidil and Nicardipine on sino-atrial node function, atrio-ventricular node function and hemodynamics

Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P＜0.01);the MAP decreased(P＜0.01)and the HR increased drastically(P＜0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.     

Expression of OPGmRNA and ODFmRNA in the patients of hip fracture due to osteoporosis

Objective：To investigate the gene expression of osteoprotegerin（OPG） and osteoclast differentiation factor（ODF） in the bone tissue of patients with hip fracture due to osteoporosis. Methods：OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers（over 50 years old） with hip fracture（Observer Group） and 30 cases of hip facture sufferers with no osteoporosis（Control group） were analyzed with the Semi-Quantitative RT-PCR method. Results：The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion：Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.     

The clinicopathological and immuohistochemical analysis of solid-pseudopapillary tumor of the pancreas： report of 9 cases

Objective：To investigate the clinical features, pathological characteristics and immunophenotype of solid-pseudopapillary tumor of the pancreas（SPTP）. Methods：Nine surgically treated cases of SPTP were retrospectively reviewed. Hematoxylin and Eosin（HE） staining and immunohistochemical staining were used to analyze all cases, and the general clinical data was collected. Results：Six patients were asymptomatic except for a palpable mass. Two patients complained of vague-epigastric pain. One patient appeared jaundice. The tumor was encapsulated and solid tissues alternately with cystic tissues. Histologically, the histological structure of solid portion was pseudopapillary with a fibrovascular core. Tumor cells were uniform and medium-sized which were arranged in sheets ets or nests or pseudopapillary patterns. Immunohistochemical studies demonstrated that SPTP proved positive in vimentin（9/9 cases）, AAT（9/9 cases）, NSE（9/9 cases）, ACT（7/9 cases）, CK20（2/9 cases）, CgA（1/9 cases）, S-100（3/gcases）, PR（4/gcases）, Syn（3/9 cases） and CD56（5/9cases）, negative in CEA and ER. Conclusion：SPTP is a tumor predominantly occurring in young women frequently without special symptoms. This tumor has various characteristical histological patterns with different immunophenotype.     

Dynamic Changes in Serum Estradiol and Progesterone levels in Patients of Premenstrual Syndrome with Adverse Flow of Liver-qi

Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.     

Real-time Three-dimensional Echocardiography in Assessment of Left Ventricular and Right Ventricular Volumes

Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.     

SCREENING FOR A 21-CHROMOSOME ABNORMALITY IN PREIMPLANTED EMBRYOS OF ELDERLY WOMEN

Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.