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21.
A case of insulinoma is reported in a patient in whom selective arterial calcium injection (SACI) tests were performed both to confirm tumor localization before surgery and to confirm complete tumor removal during surgery. An 18-year-old woman with hypoglycemic episodes was diagnosed with an insulinoma in the pancreatic body demonstrated by celiac arteriography. In a preoperative SACI test, calcium was injected into the splenic artery (SpA), gastroduodenal artery (GDA), and superior mesenteric artery (SMA). Serum immunoreactive insulin (IRI) and proinsulin levels were measured in hepatic venous samples. IRI was markedly increased after the injection of calcium into the GDA and SMA, while there was no response in IRI levels when calcium was injected into the SpA. Therefore, no occult insulinoma was revealed in the distal area fed by the SpA, although the presence of insulinoma was uncertain in the proximal pancreas. In the intraoperative SACI test, calcium was injected into the celiac artery. Insulin (determined by enzyme immunoassay) and proinsulin levels were measured in portal venous samples before and after resection of the tumor. After resection, these levels decreased in response to the calcium stimuli, confirming complete removal of the insulinoma. The SACI test was helpful to localize the insulinoma and was useful to confirm the complete removal of the tumor.  相似文献   
22.
Intrastriatal injection of the GABAA antagonist, bicuculline, caused about a 75% decrease in the inhibitory effect of the central-type benzodiazepine (BZ) agonist, clonazepam or the indoleamine hormone, melatonin, on apomorphine-induced rotation in a 6-hydroxydopamine model of dopaminergic supersensitivity. Pretreatment with the peripheral-type BZ antagonist, PK 11195 (intrastriatally or intraperitoneally), also attenuated the antidopaminergic effect of these drugs but with much less potency than bicuculline. However, the combination of both bicuculline and PK 11195, injected directly into the striatum, completely blocked the antidopaminergic action of clonazepam or melatonin. These results indicate that the antidopaminergic action of clonazepam and melatonin in the striatum involves two distinct mechanisms: (1) a predominant GABAergic activation via the BZ/GABAA receptor complex, and (2) a secondary mechanism linked to a PK 11195- sensitive BZ receptor pathway. Recent studies indicate that PK 11195 blocks BZ-induced inhibition of the adenylyl cyclase-cyclic AMP pathway in the striatum. Since cyclic AMP has been implicated in the rotational behaviour of 6-hydroxydopamine-lesioned animals, it is possible that the antidopaminergic action of clonazepam and melatonin also involves suppression of this second messenger. All rights reserved.  相似文献   
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24.
硫酸多糖对体外人脐静脉内皮细胞损伤的保护作用   总被引:8,自引:1,他引:7  
研究表明,硫酸多糖体外对多聚阳离子和氧自由基损伤的人脐静脉内皮细胞有保护作用。肝素、硫酸软骨素A抗多聚阳离子损伤作用比同浓度低分子肝素和甘糖酯强。肝素、硫酸软骨素A、甘糖酯抗氧自由基损伤作用优于同浓度低分子肝素。结果显示硫酸多糖有保护血管内皮的作用,其作用可能与所带阴离子基团有关。  相似文献   
25.
辽宁产东亚钳蝎毒镇痛作用与脑内中枢关系的研究   总被引:3,自引:0,他引:3  
应用立体定位、核团内注射与电解损毁核团技术及微电极细胞外记录方法,以猫丘脑后核内脏大神经诱发单位放电为内脏痛指标,观察向尾状核、中脑导水管周围灰质及杏仁内侧核内注入东亚钳蝎毒及在电解损毁3个核团前后PO内脏大神经诱发单位放电的变化。在损毁诸核之前刺激内脏大神经引起单位诱发放电,损毁诸核之后诱发放电减弱或消失,这与辽宁产东亚钳蝎毒注入诸核团中的作用相一致。表明蝎毒的作用部位与上述核团有关,更进一步证明蝎毒作用部位  相似文献   
26.
In a preceding study, we reported that the numbers of macrophages and polymorphonuclear leukocytes (PMN) were increased in bronchoalveolar lavage fluid (BALF) following the intratracheal instillation of nickel sulfate (NiSO4) in rats. In the present study, BALF chemotactic activities for both macrophages and PMN were measured to investigate if the increases of these inflammatory cells in BALF depend on increases in chemotactic activities in epithelial lining fluid (ELF) of the lung. Both the number of PMN and the PMN chemotactic activity peaked at 2 days post-instillation and they were significantly correlated. However, the PMN chemotactic activity was inversely correlated with concentration of leukotriene B4 (LTB4), a well-known chemotaxin. Although PMN were not observed in control BALF, LTB4 concentration in the control ELF (ca. 5×10–7 M) was estimated to have a potential to attract PMN chemotactically through a membrane in in vitro migration assay. These results suggest that the presence of LTB4 in ELF itself does not trigger transpulmonary PMN infiltration. The rat BALF were fractionated by high performance liquid chromatography (HPLC), and PMN chemotactic activity of each fraction was measured. The elution profiles of PMN chemotactic activity showed that there were at least two different chemotaxins in BALF obtained from the NiSO4-exposed rats. Macrophage chemotactic activity in BALF also peaked at 2 days post-instillation. However, the number of macrophages was not significantly correlated with the chemotactic activity for macrophage in BALF. The HPLC study showed that the macrophage chemotactic substance in the BALF obtained from NiSO4-exposed rats was different from complement fragment (C5a) and its MW was estimated to be 10 – 12 kD. Received: 1 December 1993/Accepted: 16 March 1994  相似文献   
27.
目的观察葛根素冻干粉针(麦普宁)治疗不稳定型心绞痛(Unstable angina pectoris.UAP)的临床疗效.方法将60例UAP患者随机分为治疗组30例和对照组30例.对照组采用常规治疗.治疗组在常规治疗的基础上加用葛根素冻干粉针400mg加入5%葡萄糖液250ml中静脉滴注,疗程均为14d.结果治疗组的总有效率(93%)优于对照组(66%),差异有统计学意义(P<0.05).治疗组治疗前后心电图12导联中ST段下降导联数(NST)及12导联中ST段压低数值总和(ΣST)均有明显改善(P<0.05),随访心绞痛患者6~18个月,未发现明显不良反应.结论葛根素冻干粉针剂能有效减少心绞痛发作,应用简单、监测方便,可降低心肌梗死发生率.  相似文献   
28.
通过观察益肾化浊注射液对5/6肾切除大鼠残余肾中细胞因子含量的影响,益肾化浊注射液延缓慢性肾功能衰竭(CRF)模型大鼠肾功能减退的作用机理。结果显示:益肾化浊注射液可以降低5/6肾切在鼠血清肌,尿素氮(P<0.01),下调肾组织中白细胞介素-1(IL-1)(P<0.05),白细胞介素-8(IL-8)(P<0.05)及肿瘤坏死因子(TNF)(P<0.05)的总体水平,说明益肾化浊注射液可以通过下调5/6肾切除大鼠残余肾中相关细胞因子含量,抑制促炎细胞因子对肾脏的损害,从而延缓CRF的进展。  相似文献   
29.
荞麦花粉抗贫血作用的实验研究   总被引:1,自引:0,他引:1  
用荞麦花粉的水提取液进行了抗大白鼠缺铁性贫血的研究,结果表明:荞麦花粉具有和硫酸亚铁相似的抗缺铁性贫血作用.饮用荞麦花粉提取液35d的大白鼠,生长发育良好,主要脏器未见损害.该研究为荞麦花粉的开发利用提供了实验依据.  相似文献   
30.
Ropivacaine, a new long–acting amino–amide local anaesthetic agent, and bupivacaine, in various concentrations with or without addition of adrenaline, were tested in a randomized, double–blind study using intradermal wheals. Ten non–smoking, healthy, young male volunteers participated. In series I plain solutions of ropivacaine (0.25%, 0.5%, 0.75% and 1%) and bupivacaine (0.25%, 0.5% and 0.75%) were injected intradermally and in series II the same concentrations, with the addition of adrenaline 5 ug ml-1 ( 1 :200 000), were used. The same volunteers took part in both series, with an interval of at least three weeks between the experiments. Saline was included as control in both series. Pin–pricking was used to assess the dermal analgesia. Plain solutions of ropivacaine produced significantly longer durations of dermal analgesia than did plain solutions of bupivacaine, in all tested concentrations. A significant increase in duration was seen for both local anaesthetics when adding adrenaline. Local vascular effects at the injected areas were determined by visual inspection (nil, pink, pale). Local blanching (pale) was significantly more frequent for plain solutions of ropivacaine, in all tested concentrations. Local redness (pink) was significantly more frequent with plain bupivacaine, in a dose–dependent relation. An initial redness was frequently observed for both local anaesthetics containing adrenaline, followed by blanching at most sites.  相似文献   
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