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51.
Two experiments were performed to investigate the relationship between the expression of sodium appetite and the appearance of Fos-like immunoreactivity (Fos-IR) in the brain of rats. In the first experiment, rats were depleted of sodium by treatment with furosemide 24 h prior to sacrifice and without access to either food or sodium solution. Some rats had access to distilled water, and others had no fluids available during the 24 h. All of the furosemide-treated rats showed Fos-IR in both the subfornical organ (SFO) and around the organum vasculosum laminae terminalis (OVLT). Rats with access to distilled water during the depletion period showed no Fos-IR in the supraoptic (SON) or paraventricular hypothalamic nuclei (PVN) and, in parallel behavioral studies, comparably-treated rats consumed only 0.3 M NaCl solution at the end of the 24 h. In rats that had no fluids during the deprivation period, only about one half showed Fos-IR in SON and PVN and, in parallel behavioral studies, comparably treated rats consumed both water and 0.3 M NaCI solution at the end of 24 h. In a second experiment, cerebroventricular administration of renin stimulated short latency intake of 0.3 M NaCI and water. The relative intakes of water and NaCl were comparable at a low dose of renin, but intake of water exceeded that of NaCl after higher doses. Renin induced Fos-IR in SFO, MnPO, peri-OVLT region, SON and PVN. Both Fos-IR and fluid intake were antagonized by administration of losartan, an angiotensin 11 type 1 receptor antagonist. Thus, only the circumventricular organs of the lamina terminalis showed Fos-IR during each natriorexigenic regimen in these studies. These data support the view that Ang 11 of both central and peripheral origin activates the SFO and/or peri-OVLT region and contributes to sodium appetite.  相似文献   
52.
正常血钾型周期性麻痹SCN4A基因新突变的检测   总被引:7,自引:1,他引:6  
目的 报道正常血钾型周期性麻痹 (normoPP)一家系的临床特点 ,并筛查SCN4A基因以期发现有义突变。方法 提取知情同意的患者及部分家属外周血基因组DNA ,应用变性高效液相色谱分析 (DHPLC)技术筛查患者SCN4A基因全部 2 4个外显子 ,对发现异常者进行测序分析。结果先证者常规实验室检查未见异常 ,发作期肌酸激酶 (CK) 112 6U/L(正常值 <2 0 0U/L) ,肌电图正常。发作间期行肌肉活检未见显著异常。基因研究发现先证者及其父亲 (患者 )SCN4A基因发生同一新突变G2 10 1A ,并引起氨基酸序列改变Arg6 75Gln。该突变不同于目前发现的明确导致高钾型周期性麻痹(hyperPP)的突变 ,也不同于已知的SCN4A基因所有突变。结论 normoPP患者存在一新突变Arg6 75Gln ,该突变可能与疾病相关。  相似文献   
53.
目的 本研究采用射频热凝毁损腰交感神经节,探讨背根神经节(DRG)Nav1.8磷酸化在大鼠糖尿病痛性周围神经病变中的作用。方法 采用腹腔注射链尿佐菌素诱导糖尿病痛性周围神经病变大鼠模型,取造模成功的大鼠20只,随机分为糖尿病对照组(D组)及交感神经节射频热凝组(R组),每组10只,另取10只同月龄大鼠为正常对照组(C组)。R组大鼠在X光机介导下行右侧L3,4椎旁腰交感神经节射频热凝毁损。分别于射频热凝前、射频热凝后1、2周时,采用von Frey纤维丝测定大鼠右侧后爪对机械性刺激缩足反应的阈值(PWT);射频热凝后2周,采用Western-blotting方法测定DRG细胞Nav1.8蛋白和苏氨酸磷酸化Nav1.8蛋白表达,并采用透射电镜观察大鼠腓肠神经超微病理结构。结果 与C组比较,射频热凝前D组和R组PWT降低(P<0.01)。射频热凝后1~2周,R组较D组PWT升高,但仍较C组降低(P<0.05)。C组髓鞘排列均匀,轴突内可见形态正常的线粒体;D组脱髓鞘明显,髓鞘板层排列紊乱、断裂、肿胀;R组脱髓鞘程度明显减轻,髓鞘板层局部排列紊乱、空泡形成。与C组比较,D组和R组Nav1.8蛋白表达降低(P<0.05),而苏氨酸磷酸化Nav1.8蛋白表达增高(P<0.01);R组苏氨酸磷酸化Nav1.8蛋白表达低于D组(P<0.05)。结论 DRG细胞Nav1.8的磷酸化可能是糖尿病痛性周围神经病变大鼠痛觉过敏形成的机制之一。  相似文献   
54.
目的探讨硬膜外腔注射生理盐水对剖宫产术患者腰麻效果的影响。方法择期行子宫下段剖宫产术患者60例,年龄24~30岁,体重59~73 kg,随机分为2组,每组30例,A组蛛网膜下腔注射规定剂量的0.75%布比卡因后硬膜外腔注射生理盐水5 ml;B组蛛网膜下腔注射0.75%布比卡因。按序贯法进行试验,设定布比卡因的起始剂量为9 mg,剂量梯度为1.5 mg,若上一例有效,则下一例递减一个剂量梯度,若无效则下一例递增一个剂量梯度,蛛网膜下腔阻滞有效的标准为注射布比卡因后20 min内阻滞上平面达T5。采用概率单位法计算ED50。结果A组布比卡因的ED50(5.8 mg)低于B组(8.1 mg),两组比值为0.72,95%置信区间为0.27~0.98,区间范围不包括1,差异有统计学意义(P〈0.05)。结论硬膜外腔注射生理盐水可增强剖宫产术患者腰麻的效果。  相似文献   
55.
OBJECTIVE: To investigate the effect of improvement in erectile dysfunction (ED) on sexual function and satisfaction measures in heterosexual couples in which the woman reports that sexual intercourse is unsatisfactory at least half of the time. DESIGN: Multicentre, double-blind, placebo-controlled study. SETTING: Outpatient medical clinics. POPULATION: Hundred and eighty men with ED and their female partners in whom sexual intercourse was satisfactory about half the time or less (score of < or =3 on the Female Partner of ED Subject Questionnaire question 3 [FePEDS Q3]). METHODS: Men were randomised to flexible-dose sildenafil (25, 50, and 100 mg) or placebo as needed for 12 weeks. MAIN OUTCOME MEASURES: Primary: FePEDS Q3 ('Over the past four weeks, when you had sexual intercourse, how often was it satisfactory for you?') scored as 0 (no sexual activity) and 1 (almost never or never) to 5 (almost always or always). Secondary, partners: Sexual Function Questionnaire, Female Sexual Function Index (FSFI), and ED Inventory of Treatment Satisfaction (EDITS) partner version (EDITS-Partner). Secondary, men: International Index of Erectile Function (IIEF), General Efficacy Questions, event log data, Self-Esteem And Relationship questionnaire, and EDITS. Secondary, partners and men: Dyadic Adjustment Scale. RESULTS: The intention-to-treat population included 85 sildenafil recipients (mean age 59 +/- 12 years) and 91 placebo recipients (mean age 57 +/- 11 years). Most partners (aged 20-79 years; mean, 54 years) were postmenopausal. Sildenafil compared with placebo couples had greater improvement in the primary outcome (FePEDS Q3 [P < 0.0001]) and in sexual function, intercourse success rates, and secondary sexual satisfaction measures (FSFI satisfaction domain [P < 0.0001] and IIEF satisfaction domains [P < 0.001]) and had higher treatment satisfaction (EDITS and EDITS-Partner; P < 0.0001). Several predictors of improvement were identified, and improvement in one member of the couple correlated positively with improvement in the other member. CONCLUSIONS: The interdependence of sexual function and sexual satisfaction measures between members of couples consisting of men with ED and sexually healthy women reporting infrequent satisfactory sexual intercourse underscores the importance of including partners in ED treatment discussions.  相似文献   
56.
透明质酸钠粉雾剂防治开腹术后腹腔粘连的实验研究   总被引:7,自引:3,他引:4  
为观察透明质酸钠粉雾剂防治开腹术后粘连的作用并探讨其作用机制,将30只大鼠均分为A、B两组,开腹摩擦回肠肠管形成腹腔粘连,B组损伤局部应用透明质酸钠粉雾剂,3周后观察粘连状况。结果两组共死亡3只,A组Ⅱ级粘连3只,Ⅲ级10只;B组0级、Ⅰ级及Ⅲ级各为2、11和1只,经秩和检验两组有显著性差异(P<0.05)。表明透明质酸钠粉雾剂可有效防止或减轻大鼠术后腹腔粘连,为临床防治开腹术后粘连及其并发症提供了一种简便、有效的方法。  相似文献   
57.
高效液相色谱法测定人血清中丙戊酸钠的含量   总被引:15,自引:1,他引:14       下载免费PDF全文
建立了HPLC方法测定人血清中丙戊酸钠的药物浓度。采用反相柱和乙腈-水(60∶40)作为流动相,庚酸作为内标,血样经提取后,用4-溴甲基-6,7-二甲氧基香豆素衍生化,测定波长设在λS325nm和λR398nm,内标庚酸的保留时间为4.57min,丙戊酸钠的保留时间为5.21min,线性范围为2~150μg/ml。测定了10名健康受试者单次口服丙戊酸钠片剂后不同时间的血药浓度。  相似文献   
58.
In the management of stone disease, the medical approach concerned with the prevention of stone recurrence is equally as important as the surgical removal of stones. The application of medical approach requires an understanding of the pathophysiology of stone formation. A wide variety of physiological or environmental disturbances have been identified in stone–forming patients. They include hypercalciuria, hypocitraturia, undue urinary acidity and hyperuricosuria. Reliable diagnostic protocols have been developed which are based on the presence of above derangements. The prophylactic treatment programs are directed at the correction or amelioration of underlying environmental disturbances. Conservative measures include a high fluid intake, dietary sodium and oxalate restriction, dietary calcium restriction (in absorptive hypercalciuria and primary hyperparathyroidism), and moderate animal protein restriction. Specific medical treatments chosen for discussion are thiazide, slow–release neutral potassium phosphate, potassium citrate and potassium magnesium citrate.  相似文献   
59.
B A Barres  L L Chun  D P Corey 《Glia》1988,1(1):10-30
White matter is a compact structure consisting primarily of neuronal axons and glial cells. As in other parts of the nervous system, the function of glial cells in white matter is poorly understood. We have explored the electrophysiological properties of two types of glial cells found predominantly in white matter: type 2 astrocytes and oligodendrocytes. Whole-cells and single-channel patch-clamp techniques were used to study these cell types in postnatal rat optic nerve cultures prepared according to the procedures of Raff et al. (Nature, 303:390-396, 1983b). Type 2 astrocytes in culture exhibit a "neuronal" channel phenotype, expressing at least six distinct ion channel types. With whole-cell recording we observed three inward currents: a voltage-sensitive sodium current qualitatively similar to that found in neurons and both transient and sustained calcium currents. In addition, type 2 astrocytes had two components of outward current: a delayed potassium current which activated at 0 mV and an inactivating calcium-dependent potassium current which activated at -30 mV. Type 2 astrocytes in culture could be induced to fire single regenerative potentials in response to injections of depolarizing current. Single-channel recording demonstrated the presence of an outwardly rectifying chloride channel in both type 2 astrocytes and oligodendrocytes, but this channel could only be observed in excised patches. Oligodendrocytes expressed only one other current: an inwardly rectifying potassium current that is mediated by 30- and 120-pS channels. Because these channels preferentially conduct potassium from outside to inside the cell, and because they are open at the resting potential of the cell, they would be appropriate for removing potassium from the extracellular space; thus it is proposed that oligodendrocytes, besides myelinating axons, play an important role in potassium regulation in white matter. The conductances present in oligodendrocytes suggest a "modulated Boyle and Conway mechanism" of potassium accumulation.  相似文献   
60.
Summary The effects of opioids on the permeability of the blood-brain barrier (BBB) were examined in mice with sodium fluorescein as an indicator of the permeability. The brain was perfused with saline 30 min after injection of sodium fluorescein (40 mg/kg, i. v.) and examined by fluorometry. Morphine hydrochloride (0.3–10 mg/kg, s. c.) markedly increased the brain level of sodium fluorescein dose-dependently without influencing the plasma level, when administered 20 min before sodium fluorescein injection. Intracerebroventricularly (i. c. v.) injected morphine hydrochloride (0.5 and 1.0 Erg) increased the brain sodium fluorescein level. Buprenorphine (0.1 and 0.5 mg/kg, s. c.) was also effective. However, pentazocine, ethylketazocine, U-50488H and SKF-10047 had no significant influence. The i.c.v. administration of [D-Ala2, McPhe4, Gly(ol)5]enkephalin (0.1 g) and [D-Ala2, D-Leu5]enkephalin (0.5 g) but not of [D-Thr2, Leu5]enkephalin-Thr increased the brain level of sodium fluorescein significantly. A small dose of naloxone (i. p.) significantly inhibited the effects of morphine, buprenorphine, [D-Ala2, McPhe4, Gly(ol)5]enkephalin and [D-Ala3, D-Leu5]enkephalin. ICI-174864 co-administered i. c. v. with [D-Ala2, D-Leu5]enkephalin was ineffective in antagonizing the effect of the latter. These findings suggest that the stimulation of µ opioid receptors results in an increase in BBB permeability to sodium fluorescein. Send offprint requests to K. Saeki  相似文献   
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