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1.
We evaluated possible modulation by angiotensin III (AIII) of the interactive effect of noxious stimuli and elevation in systemic arterial pressure on the responsiveness of neurons in the nucleus reticularis gigantocellularis (NRGC) of the medulla oblongata. Combined extracellular single-neuron recording and microiontophoresis were carried out on male, adult Sprague-Dawley rats anesthetized with pentobarbital sodium. The responsiveness of NRGC neurons to nociception (tail clamp) and/or transient hypertension elicited by phenylephrine (5 μg/kg, i.v.), in the absence or presence of AIII, was used as the experimental index. Microiontophoretic application of the heptapeptide suppressed the responses of spontaneously active NRGC neurons to individually delivered nociception or hypertension. Interestingly, the preferential reduction in responsiveness to tail clamp upon simultaneous elevation in arterial pressure was reversed to one that favored nociception in the presence of AIII. These actions of the heptapeptide appeared to be receptor-specific, since they were discernibly blocked by its selective antagonist, Ile7-angiotensin III. Our results reveal that neuropeptides such as AIII may differentially modulate neuronal responsiveness according to the prevailing physiologic input(s) to the central nervous system of the animal.  相似文献   
2.
Somatic cell and gene therapy involve the application of biological technologies to an individual patient through the use of living cells which provide a therapeutic benefit (Aliski, 1991). Various forms of cellular and gene therapies are being developed and evaluated in an increasing number of clinical trials for congential and acquired disorders. The potential and progress of these therapeutic applications have resulted in an increasing effort by the Food and Drug Administration (FDA) to develop the regulatory framework under which these therapeutic approaches would insure safety and efficacy, the primary mandate of the FDA.Over five years ago Cellcor began to define the parameters, specifications, and conditions relevant to a Quality Assurance/Quality Control (QA/QC) program that has evolved to insure safety and maximize the efficacy of applications of the company'sex vivo technology, autolymphocyte therapy. Autolymphocyte therapy is an outpatient form of somatic cell immunotherapy based upon the infusion of T cells that have been activatedex vivo using a combination of previously generated autologous cytokines and an anti-CD3 monoclonal antibody.We have been able to demonstrate the feasibility for the safe, controlled, and consistent preparation and delivery of a cellular therapy by application of relevant GMP regulations. This presentation reviews aspects of this program and chronicles our experience which at present amounts to over 4400 infusions for over 700 patients. This program provides a high degree of assurance that a cellular therapy program can be carried out in a multisite mode involving hundreds of patients through the strict adherence to cGMP as set forth in existing regulations. It would be prudent that developers of cellular andex vivo gene therapies establish a similar cell processing and QA/QC infrastructure at an early developmental stage to optimize safety and reproducibility and facilitate regulatory review.  相似文献   
3.
The present study was undertaken to further characterize the nucleus reticularis gigantocellularis (NRGC) of the medulla oblongata in the central processing of nociceptive and cardiovascular signals, and its modulation by metenkephalin. In Sprague-Dawley rats anesthetized with pentobarbital sodium, we found that all 125 spontaneously active NRGC neurons that responded to noxious stimuli (tail clamp) also exhibited arterial pressure-relatedness. Forty neurons additionally manifested cardiac periodicity that persisted even during nociceptive responses. While maintaining their cardiovascular responsive characteristics, the nociception-related NRGC neuronal activity was blocked, naloxone-reversibly (0.5 mg/kg, i.v.), by morphine (5 mg/kg, i.v.). Microiontophoretically applied met-enkephalin suppressed the responsiveness of NRGC neurons to individually delivered tail clamp or transient hypertension induced by phenylephrine (5 µg/kg, i.v.). Interestingly, in NRGC neurons that manifested both nociception and arterial pressure relatedness, the preferential reduction in the response to noxious stimuli upon simultaneous elevation in systemic arterial pressure was reversed to one that favored nociception in the presence of met-enkephalin. All actions of met-enkephalin were discernibly blocked by the opioid receptor antagonist, naloxone. Our results suggest that individual NRGC neurons may participate in the processing of both nociceptive and cardiovascular information, or in the coordination of the necessary circulatory supports during nociception. In addition, neuropeptides such as met-enkephalin may exert differential modulation on neuronal responsiveness according to the prevailing physiologic status of the animal. They also showed that NRGC may be a central integrator for pain and cardiovascular-related functions.  相似文献   
4.
高原人体左心室舒张功能和顺应性的改变   总被引:1,自引:0,他引:1  
应用同步描记心电图、心音图、颈动脉搏动图和心尖搏动图以测定高原人体的左心室舒张功能和顺应性。在4个不同海拔高度进行实验,即76m(海平对照)、2161m、3270m和4179m,每一高度40名健康男性青年,高原3组世居、移居各20名。结果显示:随着海拔增高,主动舒张时间指数(TRTI)有减小趋势,RF波相对振幅(F/H)逐渐降低,A波相对振幅(A/D)则渐趋增大,3270m以上增大明显(p<0.05),舒张振幅时间指数(DATI)逐渐降低,3270m以上差异极显著(p<0.001)。高原世居与移居者相比,在海拔4179m出现明显差别,移居组TRTI、DATI、F/H较低而A/D较高(D<0.05)。测定射血前期与左室射血时间比值(PEP/LVET)、射血分数(EF)及左室周径纤维平均缩短速度(mVcf)3项指标作对照,显示在此高度左室收缩功能仍能保持。高原慢性心肌缺氧可能是导致左室舒张功能和顺应性轻度降低的原因。  相似文献   
5.
Data drawn from the perspectives of paleontology, comparative anatomy, embryology, teratology, and normal adult variation were analyzed with nine homology criteria in order to determine the homologues of the stapedial artery in adult humans. It was determined that 1) the stem of the stapedial artery does not persist within the cranial cavity; 2) the stem of the ramus inferior is retained in its entirety and forms the upper portion of the stem of the middle meningeal artery; 3) the proximal part of the ramus infraorbitalis is normally absent and is replaced by a collateral shunt arising from the ramus mandibularis; 4) the ramus mandibularis is retained and forms the lower portion of the middle meningeal stem and the inferior alveolar artery; 5) the most proximal portion of the maxillary artery is formed by an anastomotic shunt connecting the external carotid artery to the ramus mandibularis; 6) the anterior division of the ramus superior is normally present and well developed; 7) the posterior division of the ramus superior is present in many individuals; and 8) the junction of the two divisions of the ramus superior with the ramus inferior usually migrates to the floor of the middle cranial fossa. The range of human arterial patterns, and those of all other euprimates, can be derived from a hypothetical primitive pattern that is very similar to that of primitive rodents. In this pattern, the stapedial artery stem enters the middle cranial fossa and trifurcates into the anterior and posterior divisions of the ramus superior and the ramus inferior. In their evolution, strepsirhines initially lose the ramus inferior and haplorhines initially reduce the stapedial artery stem.  相似文献   
6.
7.
摘要 目的:探讨布南色林联合团体心理治疗慢性精神分裂症(SZ)的疗效,分析其对认知功能、社会功能和服药依从性的影响。方法:选取124例慢性SZ患者随机分为对照组和观察组,对照组口服布南色林治疗,观察组在对照组基础上加以团体心理治疗,疗程均为2个月。治疗后,采用阳性与阴性症状量表(PANSS)和临床疗效总评量表-疾病严重程度(CGI-SI)评估两组患者治疗后的疗效,采用威斯康星卡片分类测验(WCST)评估两组患者治疗前后的认知功能,采用个人和社会功能量表(PSP)评估两组患者治疗前后的社会功能,评定两组患者治疗后的服药依从性。结果:治疗后,两组患者PANSS阳性症状、阴性症状、一般精神病理评分以及总评分均低于治疗前,且观察组低于对照组(P<0.05);两组患者CGI-SI评分均低于治疗前,且观察组低于对照组(P<0.05);两组患者WCST总应答数评分均高于治疗前,且观察组高于对照组(P<0.05);两组患者PSP总评分均高于治疗前,且观察组高于对照组(P<0.05);观察组服药依从性优于对照组(P<0.05)。结论:布南色林联合团体心理治疗较单一布南色林治疗慢性SZ的治疗效果更好,能更好地提高患者的认知功能、社会功能以及服药依从性,值得临床借鉴推广。  相似文献   
8.
建立大脑中动脉闭塞(model of middle cerebral artery occlusion,MCAO)大鼠模型,研究阿加曲班对大鼠不同时间脑缺血再灌注损伤血小板功能的影响。将120只健康雄性SD大鼠随机分为假手术组(Sham)、模型组(Model)和阿加曲班给药组(Argatroban),其中Argatroban组分为4组:Argatroban+30 min组、Argatroban+1 h组、Argatroban+3 h组和Argatroban+7 h组,Sham组和Model组40只,其余各组每组10只。线栓法制备大鼠MCAO模型,术中输注Argatroban,剂量为0.3μg·kg^-1·min^-1,完成手术前5 min停止输注。手术完成后,Sham组和Model组分别于术后30 min、1 h、3 h和7 h处死10只取样;Argatroban给药组5个时间点处死取样。检测大鼠血浆血细胞数量,并计数骨髓有核细胞数的变化。采用流式细胞仪检测血小板-白细胞聚集体(platelet-leukocyte aggregates,PLA)表达水平,观察活化部分凝血活酶时间(activated partial thromboplastin time,APTT)、血小板计数变化,ELISA检测血浆D-二聚体和TAT。结果显示,与Sham组相比,Model组大鼠的红细胞(RBC)、白细胞(WBC)、血红蛋白含量(HGB)和中性粒细胞(GR)数都显著升高(p<0.05),且与给药组没有统计学差异。Sham组、Model组和Argatroban给药组的骨髓有核细胞数也没有统计学差异。与Sham组相比,Model组PLA表达水平极显著升高(p<0.01),Argatroban+30 min组PLA表达水平却低于Sham组,但没有统计学差异,Argatroban+1 h组高于Sham组和Argatroban+30 min组(p<0.05),Argatroban+3 h组和Argatroban+7 h组高于Argatroban+1 h组低于Sham组。术后各组的血小板计数均高于Sham组(p<0.05),Argatroban各组的血小板计数要低于Model组(p<0.05),并在30 min时达到最低,30 min以后血小板升高,但是1 h以后血小板不再升高,趋于稳定。Argatroban各组PT和APTT虽略有降低,但是与Sham组和Model组并没有统计学差异。造模后各组TAT、D-二聚体水平显著升高,Argatroban各组TAT水平较模型组明显降低(p<0.05),Argatroban+30 min组水平最低。MCAO模型大鼠血液呈现高凝状态,凝血功能和纤维蛋白溶解功能亢进,血小板活化增强,阿加曲班可对此起到改善作用。  相似文献   
9.
The in vitro conversion of (1S,3S)-1-dimethoxylethyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid, (1S,3S)-DCCA, in rat plasma is monitored by HPLC-FT-ICR-MS. We show that the in vitro conversion of (1S,3S)-DCCA in rat plasma for 1 h leads to forming (6S/12aS)-bisdimethoxyethylheptachpyridone, reflecting intermolecular condensation of (1S,3S)-DCCA, and the in vitro conversion of (6S/12aS)-bisdimethoxyethylheptachpyridone in rat plasma for 1 h leads to forming (6S/12aS)-heptachpyridone, reflecting hydrolysis of (6S/12aS)-bisdimethoxyethylheptachpyridone. At a dose of 1.0 μmol/kg (6S/12aS)-heptachpyridone orally inhibits venous thrombosis and arterial thrombosis in vivo. Bleeding time, clotting time and international normalized ratio show that at this dose (6S/12aS)-heptachpyridone has no bleeding risk, does not lengthen clotting time and does not change the exogenous coagulation pathway. We also show that the reactions promoted by rat plasma are easy to practice by chemical synthesis. Thus our findings build a bridge across the in vivo conversion and the application.  相似文献   
10.
摘要 目的:探讨高频振荡通气(HFOV)联合肺表面活性物质(PS)对治疗新生儿急性肺损伤/急性呼吸窘迫综合征(ALI/ARDS)的疗效及对肺动态顺应性的影响。方法:选择2018年1月至2020年12月我院新生儿科收治的160例ALI/ARDS患儿进行研究,按照随机数表法分为观察组和对照组,每组80例。对照组患儿给予常频通气(CMV)模式联合PS治疗,观察组患儿给予HFOV模式联合PS治疗。比较两组患儿一般治疗情况、治疗前后肺动态顺应性、动脉血氧分压(PaO2)、动脉二氧化氮分压(PaCO2)、氧合指数(OI)、血清肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-6、IL-10的变化,以及治疗期间并发症发生情况。结果:观察组胸片恢复正常时间、机械通气时间、氧暴露时间、ICU停留时间、住院时间结果均明显短于对照组(P<0.05),两组患儿病死率相比较,无统计学意义(P>0.05);治疗后12 h、24 h、48 h时,观察组肺动态顺应性及PaO2、OI结果明显高于对照组,PaCO2明显比对照组低,差异有统计学意义(P<0.05);治疗后48 h时,观察组血清TNF-α、IL-6水平均明显低于对照组,IL-10明显比对照组高,差异有统计学意义(P<0.05);两组治疗期间,呼吸机相关性肺损伤、颅内出血、气漏、呼吸道感染的总发生率比较,无统计学意义(P>0.05)。结论:HFOV联合PS治疗新生儿ALI/ARDS疗效明显,可有效改善患儿肺动态顺应性,促进血气分析指标恢复,且可降低炎症因子的表达,值得推广应用。  相似文献   
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