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101.
Summary A specific radioimmunoassay for the quantitative measurement of ACTH 4-10 and a procedure for its extraction from plasma have been developed.Its pharmacokinetics was studied in eight healthy male volunteers given ACTH 4-10 125 µg/kg body weight as a bolus i.v. injection, by infusion and intranasally. Following the i.v. bolus, plasma levels rapidly declined biexponentially, with half-lives of 0.39±0.05 min for the -phase and 3.84 ± 1.5 min for the -phase (mean±SD). The constant rate i.v. infusion yielded steady-state levels between 0.74 and 5.06 ng/ml plasma. Administered as intranasal spray, absorption of intact ACTH 4-10 was low and variable (maximal bioavailability 7.6%).The results are discussed in relation to the dose-dependent effects of ACTH 4-10 on the auditory evoked potential.  相似文献   
102.
Summary These studies were designed to determine the role of the central nervous system, the sympathetic nervous system, the adrenal glands and the renal sympathetic nerves in yohimbine-induced renin release in conscious rats. Yohimbine (0.3–10 mg/kg, s.c.) caused time- and dose-related increases in plasma renin activity (PRA) and concentration (PRC) which were accompanied by time- and dose-related elevations of plasma norepinephrine (NE) and epinephrine (Epi) concentrations. Significant positive correlations were found between the increases in PRA and the increases in plasma NE and Epi concentrations caused by yohimbine, and propranolol (1.5 mg/kg, s.c.) blocked 90% of yohimbine (3 mg/kg, s.c.)-induced renin release. Over the entire spectrum of doses of yohimbine, the increases in PRA and plasma NE and Epi concentrations were positively correlated with the decreases in mean arterial pressure (MAP), but the -intercept was positive in every case and the 1 mg/ kg dose of yohimbine consistently increased PRA independent of any change in MAP. Complete renal denervation, as evidenced by a greater than 90% reduction in renal NE content, did not alter the increase in PRA caused by yohimbine (3 mg/kg, s.c.). An increase in circulating plasma catecholamine concentrations appeared to mediate yohimbine-induced renin release since propranolol prevented the rise in PRA caused by yohimbine in renal denervated rats. Prior adrenalectomy (Adx) also failed to prevent the rise in PRA produced by yohimbine (3 mg/kg, s.c.), but a combination of Adx and renal denervation caused a significant impairment of yohimbine-induced renin release. However, neither Adx alone nor the combination of Adx and renal denervation affected the increase in plasma NE concentration caused by yohimbine. Complete transection of the spinal cord at C8 caused a drastic reduction in plasma catecholamine concentrations but did not change basal PRC. Yohimbine (3 mg/kg, s.c.) did not increase PRC or plasma catecholamine concentrations after spinal transection. Based on these results, we conclude that 1) the stimulation of renin release by yohimbine is a secondary neurohormonal consequence of the generalized increase in sympathetic activity caused by yohimbine, 2) the sympathoadrenal activation produced by yohimbine results from an action in the brain which is amplified by the simultaneous blockade of prejunctional 2-adrenoceptors and 3) vasodepressor effects of the larger doses yohimbine cause a baroreflexly-mediated increase in sympathetic activity which interacts in a positive fashion with the central and peripheral sympathoexcitatory effects of yohimbine. Send offprint requests to T. K. Keeton  相似文献   
103.
目的 探究乙酰胆碱酯酶(acetylcholinesterase, Ache)、P-选择素(P-selectin)、细胞周期素依赖蛋白激酶5(cyclin-dependent kinase 5,CDK5)在病毒性脑炎(viral encephalitis, VE)中的表达及相关性。方法 本研究选取在本院健康体检及神经内科就诊治疗、住院治疗的病毒性脑炎患者130例作为研究对象,并纳入研究组,根据患者的病情时间将其分为急性期和恢复期,其中急性期组85例,恢复期组45例。根据患者的临床表现,将其分为轻度组和重度组,其中轻度组76例,重度组54例,选择同期在我院接受体检的健康患者60例作为对照组。应用丁酰硫代胆碱底物法检测Ache水平;酶联免疫吸附法检测血清P-selectin水平;CDK5分离试剂盒检测CDK5水平。观察研究组和对照组、急性期和恢复期及重度组和轻度组患者Ache、P-selectin、CDK5水平,分析病毒性脑炎患者Ache、P-selectin和CDK5之间相关性,利用ROC曲线比较Ache、P-selectin、CDK5单独检测及联合检测在VE中的诊断价值。结果 研究组A...  相似文献   
104.
目的:研究不同孕期阶段(早、中、晚)孕妇凝血四项、血浆纤维蛋白(原)降解产物[plasma fibrin/fibrinogen degradation products, FDP]、D-二聚体的变化及临床意义,为临床诊疗提供理论支持。方法:回顾性分析2021年1月至2021年12月200例孕妇就诊资料中的凝血四项,纤维蛋白原(fibrinogen, FIB)、凝血酶原时间(prothrombin time, PT)、凝血酶时间(thrombin time, TT)、活化部分凝血活酶时间(activated partial thromboplastin time, APTT)。并对FDP与D-二聚体的检测结果进行统计分析,比较孕早期、中期、晚期三个阶段凝血四项、FDP和D-二聚体水平的变化。结果:孕早期、孕中期与孕晚期PT水平比较,差异有统计学意义(P<0.05);孕早期、孕中期与孕晚期三个阶段的TT相比,差异无统计学意义(P>0.05);孕早期的APTT明显长于中期、晚期孕妇,差异有统计学意义(P<0.05);孕早期、中期、晚期孕妇,随着孕周的增加,FIB水平逐渐升高...  相似文献   
105.
背景 估算肾小球滤过率(eGFR)是反映慢性肾脏病严重程度的量化指标之一。研究表明糖尿病前期血糖升高可增加慢性肾脏病风险,但对eGFR直接影响报道较少。目的 探讨社区人群中空腹血糖(FPG)受损患者血糖水平对eGFR的影响。方法 选择2020年1—12月于南昌大学第二附属医院体检中心体检的人群,收集一般资料与临床资料(包括既往史、性别、年龄、体质指数、血压、尿酸、血脂、FPG、尿常规、血肌酐),经相应纳入标准与排除标准筛选,最终纳入28 601例受试者。根据FPG水平将受试者分为FPG升高组(5.6 mmol/L≤FPG<7.0mmol/L)、FPG正常组(3.9 mmol/L≤FPG<5.6 mmol/L),比较两组一般资料与临床资料。为明确FPG对e GFR影响,采用个案匹配控制对两组受试者进行多因素(性别、年龄、平均动脉压、尿酸、总胆固醇、体质指数)匹配,采用Mann-Whitney U秩和检验比较匹配后两组一般资料。采用Spearman秩相关检验分析FPG与eGFR在FPG升高组、FPG正常组及匹配后FPG升高组、FPG正常组间的相关性。结果 共获得FPG正常组患者...  相似文献   
106.
段文江  陈勇  丁一  刘国印 《西部医学》2023,35(8):1152-1157
探讨血清炎性因子在骨折延迟愈合患者富血小板血浆治疗中的变化。方法 选取2020年4月—2021年4月我院收治的98例骨折患者,均予以富血小板血浆联合钢板内固定手术治疗,根据术后6个月内是否发生骨折延迟愈合分为延迟愈合组(37例)和正常愈合组(61例)。分别于骨折后1、4、8、12周采集患者血清样本,采用酶联免疫吸附法检测血清人可溶性细胞间粘附分子-1(sICAM-1)、人可溶性血管细胞粘附分子-1(sVCAM-1)、肿瘤坏死因子-α(TNF-α)等炎症因子水平,并绘制ROC曲线,评估其对骨折延迟愈合的预测价值。采用酶联免疫双抗体夹心法检测血清骨钙素(BGP)、Ⅰ型胶原氨基端肽原(PINP)、碱性磷酸酶(ALP)、胰岛素样生长因子-1(IGF-1)等骨生化代谢指标水平,并采用Pearson分析骨生化代谢指标与炎症因子的关系。结果 骨折1周时,两组患者血清sICAM-1、sVCAM-1、TNF-α等炎症因子水平比较差异无统计学意义(P>0.05);骨折4、8、12周时,延迟愈合组患者血清sICAM-1、sVCAM-1、TNF-α等炎症因子水平均高于正常愈合组(P<0.05),且随着时间推移,两组患者血清sICAM-1、sVCAM-1、TNF-α水平先升高后降低,但延迟愈合组炎症因子水平波动较正常愈合组更明显(P<0.05)。骨折1周时,两组患者血清BGP、PINP、ALP、IGF-1等骨生化代谢指标水平比较差异无统计学意义(P>0.05),且两组各时间点血清ALP水平比较差异无统计学意义(P>0.05); 骨折4、8、12周时延迟愈合组患者血清BGP水平逐渐升高并高于正常愈合组,血清IGF-1水平逐渐升高但低于正常愈合组,骨折8、12周时延迟愈合组患者血清PINP水平低于正常愈合组(P<0.05)。Pearson相关性分析结果显示,血清sICAM-1、sVCAM-1、TNF-α等炎症因子水平与血清BGP呈正相关(r=0.523,P<0.001),与血清IGF-1呈负相关(r=-0.467,P<0.001)。ROC曲线分析结果显示,骨折8周时,血清炎症因子水平诊断骨折延迟愈合的曲线下面积高于0.7,提示其具有较好诊断价值,且联合检测对骨折延迟愈合诊断的灵敏度更高(P<0.05)。结论 延迟愈合骨折患者血清sICAM-1、sVCAM-1、TNF-α等炎症因子指标水平随骨折时间增加呈现先升高后降低变化,炎症因子指标水平波动明显,且术后8周时血清炎症因子对预测骨折延迟愈合具有一定参考意义  相似文献   
107.
Substance P is one of the peptides released from sensory nerves that mediate "neurogenic inflammation." Although substance P-immunoreactive (SP-IR) axons are known to be present within the mucosa of the respiratory tract, the relative extent of the innervation of various components of the mucosa is not known. Therefore, we determined the distribution and number of SP-IR axons in the rat trachea and bronchi, by using immunohistochemistry on tissue whole mounts. Specifically, we sought to learn whether these axons directly innervate the postcapillary venules involved in neurogenic plasma extravasation, the arterioles involved in neurogenic vasodilatation, and the airway smooth muscle involved in bronchoconstriction in pathogen-free, adult male F344 rats. We found that 90% of the SP-IR axons were single axons, usually having varicosities. Eighty-five percent of these were in the epithelium, 6% innervated arterioles, and the remainder elsewhere in the lamina propria. Only 10% of the mediator-sensitive postcapillary venules (i.e., venules labeled with Monastral blue pigment after challenge with capsaicin or substance P) were within 10 microns of SP-IR axons. SP-IR axons were more than 10 times as frequent in the smooth muscle of the distal bronchi as in the trachea. Capsaicin pretreatment (168 mg/kg over 7 days) reduced the number of SP-IR axons in the trachea by 96%, which is consistent with their being sensory. Unilateral vagotomy reduced the number of SP-IR axons bilaterally in the trachea and ipsilaterally in the main stem bronchus. Using an antibody to Protein Gene Product 9.5 as a nonspecific marker for all nerves in the trachea, we determined that SP-IR axons constituted 90% of the axons in the epithelium, 32% of the axons on arterioles, and only 4% of the axons in the smooth muscle. We conclude that most SP-IR nerves in the trachea are sensory axons and most of these axons end in the epithelium. SP-IR axons innervate mucosal arterioles, but few innervate postcapillary venules. Therefore, the mechanism by which sensory axons evoke plasma extravasation from these venules is likely to involve the diffusion of the peptide or a secondary mediator from the epithelium or from the arterioles upstream.  相似文献   
108.
Tumor cells infected with a retrovirus vector (VIK) containing the herpes simplex virus thymidine kinase (HSV-TK) gene can be selectively killed by treatment with nucleoside analogues, such as ganciclovir. To mediate delivery of the HSV-TK gene to "recipient" tumor cells, "donor" C6 rat glioma cells infected with the VIK vector (C6VIK) were superinfected with wild type Moloney murine leukemia virus (WT Mo-MLV). These modified donor cells (C6VIKWT) produced both wild type retrovirus and the VIK vector. In culture, C6VIKWT cells were 300-fold more sensitive to the toxicity of ganciclovir than were C6VIK cells, suggesting that the presence of wild type retrovirus contributed to the toxicity. Co-culture of C6VIKWT cells with the C6 subline, C6BAG, sensitized the latter to ganciclovir treatment. Nude mice inoculated subcutaneously with a mixture of C6VIKWT and C6BAG cells showed regression of subsequent tumors when treated with ganciclovir. The observations show that tumor cells modified in culture by infection with a retrovirus bearing the HSV-TK gene and wild type retrovirus are not only sensitive to ganciclovir, but can transfer this sensitivity to neighboring "naive" tumor cells in culture and in vivo.  相似文献   
109.
The DNA from several clinical isolates of varicella-zoster virus (VZV) were compared with the DNA from the vaccine strain VZV using three restriction endonucleases: BamHI, BgII, and HpaI. When electrophoresed through an agarose gel, the vaccine DNA digestion pattern was significantly different from the digestion patterns of the wild-type DNAs. Variations in the digestion pattern of the separate clinical isolates were also observed.  相似文献   
110.
Elevation of the serum angiotensin-converting enzyme (sACE) level and hepatic granulomas were found during a clinical relapse in a 22 year old patient with acute viral hepatitis type A (AVH-A). The serum transaminase level and sACE level remained high for more than 6 months. In the biopsied specimen of the liver, fibrous rings of granulomas composed of collagen types I, III, and V were observed. Furthermore, the localization of ACE was visible in the rough endoplasmic reticulum of epithelioid cells of granulomas in the liver under electron microscopy using the indirect immunoperoxidase method. These results suggest that granuloma cells in the liver caused by hepatitis A may be involved in ACE production. In addition, other diseases associated with the presence of granulomas in the liver, such as lymphoma, cytomegalovirus infection, visceral leishmaniasis, and lupoid hepatitis, were ruled out. However, the hepatic granulomas disappeared with the healing of AVH-A. In this regard, the present case is considered to be one of the very few cases of hepatic sarcoidosis.  相似文献   
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