Interaction of peripheral and central respiratory drives in cats I. Effects of sodium cyanide as a peripheral chemoreceptor stimulus at different levels of CSF pH

In cats anesthetized with chloralose-urethane, the central respiratory chemoreceptors were exposed to mock CSF of pH 7.02, 7.20, or 7.57. The right carotid body was simultaneously stimulated by intracarotid injections of 40, 80, or 160 μg sodium cyanide in 200 μl Ringer solution. The left carotid nerve and, in some animals, both vagosympathetic truncs were dissected. It could be demonstrated the the increase in ventilation produced by application of NaCN to the peripheral chemoreceptors is significantly larger at high than at low mock CSF pH (i.e. at low than at high central stimulus intensity). In vagotomized cats the responses of V_T and gelai to NaCN similarly depend upon CSF pH; they are somewhat larger, though, than in intact animals. These results are discussed as compared with results reported by different authors. Supported by the Deutsche Forschungsgemeinschaft (Be 477)     

Effects of carotid sinus nerve transection on changes in neuropeptide Y and indolamines induced by long-term hypoxia in rats

 Long-term hypoxia induces changes in neuropeptide-Y-like immunoreactivity (NPY-LI) and/or in the content of serotonin (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) at the central level. To determine whether these alterations depend on the integrity of carotid body (CB) chemoreceptors, intact rats or those whose carotid sinus nerve was transected (CSNT) were exposed to hypoxia (10% O₂) or to normoxia for 14 days. Thereafter, NPY-LI, 5-HT and 5-HIAA levels in discrete brain regions were determined. The increase in NPY-LI in the ventrolateral medulla oblongata (VLM) of intact hypoxic rats was mostly abolished after CSNT and therefore is mainly mediated by CB chemoreceptors. In contrast, other hypoxia-induced changes were similar or even enhanced in CSNT as compared to intact rats and therefore do not depend on the integrity of CB chemoreceptors. This was the case for the increase of NPY-LI in the striatum and the caudal dorsomedian medulla oblongata (DMM), as well as for all the changes in 5-HT and 5-HIAA in the DMM, the VLM, the raphe nuclei, the striatum and the frontal cortex. We propose that long-term hypoxia alters brain NPY-LI and indolamine content through the stimulation of CB chemoreceptors or ancillary chemoreceptors, as well as through local biochemical or morphological mechanisms. Received: 5 May 1998 / Received after revision: 27 July 1998 / Accepted: 3 September 1998     

脑梗塞患者颈动脉粥样硬化斑块的超声研究

目的探讨脑梗塞患者颈动脉粥样硬化病变程度和特征,评价彩色多普勒超声对该粥样斑块的诊断价值.方法应用HP5500超声仪,对35例脑梗塞患者和46例正常人进行颈动脉检查.结果脑梗塞组颈动脉粥样硬化斑块检出率、斑块记分均显著高于对照组[分别为85.7%和21.7%,P＜0.01;(6.745±3.214)mm和(3.408±3.613)mm,P＜0.001],且脑梗塞组软斑比例为55.8%,显著大于对照组33.3%(P＜0.01),脑梗塞组斑块表面不规则即Ⅱ、Ⅲ度的比例亦显著大于对照组(41.9%/11.1%,11.6%/0%,P＜0.05).结论脑梗塞的发生与颈动脉粥样硬化病变密切相关;软斑块是发生脑梗塞的主要危险;超声检查对颈动脉粥样硬化具有诊断价值,可为脑梗塞的预防与治疗提供参考资料.     

颈动脉粥样斑块与冠状动脉病变

目的 研究颈动脉粥样斑与冠状动脉病变的关系。方法 将82例冠心病待排和冠心病患者按冠状动脉造影结果分成正常组和冠脉粥样病变组,同期超声检测颈动脉粥样硬化程度。结果 颈动脉粥样斑块与冠脉弱粥样硬化之间有较密切的关系。颈动脉粥样斑块对狭窄性冠状动脉病变预测的敏感性为71.7%,特异性为91.9%,阳性和阴性预测值分别为91.7%和73.9%,其准确性为81.7%。结论 颈动脉超声检测可作为预测冠状动脉粥样硬化有价值的指标。     

模拟器训练在实施股动脉穿刺点ExoSealTM封堵止血系统操作的多中心对照研究

背景与目的：介入手术已成为血管外科的主要治疗手段,对于手术直接相关的股动脉穿刺点封堵处理是手术操作收尾的一个重要环节。鉴于国内外目前尚缺乏关于封堵止血系统模拟器训练应用效果的高级别证据,本研究旨在评估模拟器训练在实施股动脉穿刺点ExoSealTM封堵止血系统操作的临床应用效果以及在血管介入操作基础教学培训中的应用价值。 方法：采用前瞻性对照设计,选择2020年5月—2020年10月7个中心的8名血管介入医师分别用两种不同方式进行封堵操作培训。4名血管介入医师通过阅读ExoSealTM说明书和观看视频进行培训（对照组）,另4名血管介入医师的培训方式为在前者基础上增加专业人员指导下的模拟器使用（研究组）。培训结束后,在主诊医师监管下,每名医师对接受血管介入手术,并在股总动脉使用6 F鞘管的患者,采用ExoSealTM封堵止血系统对穿刺点进行封堵。两组医师各操作50例患者,比较两组的操作时间、出血量、器械成功率、股动脉栓塞发生率、二次干预率、24 h内发生血肿率。 结果：研究组在ExoSealTM封堵止血系统操作中,所需的操作时间和出血量均少于对照组（24.50 s vs. 30.00 s,P=0.003;8.60 mL vs. 11.22 mL,P=0.019）。研究组的器械成功率（98.0%）高于对照组（96.0%）,但差异无统计学意义（P=0.558）。两组均无动脉栓塞、二次干预和24 h内发生血肿情况。 结论：ExoSealTM封堵止血系统模拟器的训练能够提高股动脉封堵的安全性和有效性。该模拟器的训练应常规用于血管介入操作的基础教学培训中。     

A rare instance of Wilkie’s syndrome in a young male during the holy month of Ramadan

Introduction and importanceWilkie’s syndrome[SMA(Superior Mesenteric Artery) syndrome or Cast syndrome]) is a unique and rare presentation which may be included in the differential diagnosis especially when a Gastric outlet obstruction is being investigated and there is a history of an associated element of rapid weight loss. The purpose of presenting this case report is its uniqueness given a history of intermittent fasting rather than the usual eating disorders.Case presentationA crescendo worsening of symptoms of intractable vomiting, inability to eat, upper abdominal gas bloating and post meal abdominal pain since one week in a patient during a period of fasting for the first time had been observed.Clinical discussionAfter initial resuscitation, an ultrasound abdomen and an abdominal x ray revealed a distended stomach and a nasogastric tube was immediately introduced to avoid aspiration. A CT scan of the abdomen with contrast revealed the compressed duodenum in the aortomesenteric angle and the diagnosis of SMA syndrome was confirmed. An upper gastrointestinal endoscopy was also done to rule out other causes and it was found to be normal.ConclusionIn an acute presentation, the response to conservative management is remarkable and in the absence of any possible future reoccurrences the surgical options may be avoided. High index of suspicion, appropriate radiological diagnosis and stepwise treatment options may guide the troubled patient towards recovery in this rare presentation. A proper history taking is key in diagnosing such a condition and does not have to be limited to eating disorders, typically.     

Beta-adrenergic drugs do not affect phrenic nerve afterdischarge

Summary In anesthetized cats, a carotid sinus nerve was stimulated electrically. After this stimulation the time course of the afterdischarge in the phrenic nerve activity was studied in the control situation, during infusion of isoprenalin and after administration of metoprolol. The time courses were identical in all situations.It is concluded that in spite of the fact that the beta-adrenergic drugs change the steady state phrenic nerve activity, the afterdischarge is unchanged and therefore probably mediated by a separate mechanism. A comparison is made with analogous findings in patients with a hyperventilation syndrome.     

红霉素缓释微囊的制备及其释药机理的研究

本文旨在探讨红霉素微囊的制备及体外缓释机理。以明胶等为囊材,用红霉素制成微囊,研究微囊的厚度及孔隙度对药物释放速率的影响。进行理论分析,与实验结果相符性较好。     

冠心病患者冠状动脉内成形及支架术前后QT离散度的变化

目的 体表心电图ＱＴ离散度（ＱＴｄ）增大在冠心病患者是预测室性心律失常事件的有用指标。旨在估价冠心病患者经皮冠状动脉腔内成形主支架术（ＰＴＣＡ＋ｓｔｅｎｔ）前后对ＱＴ离散度的影响。方法 对６０例冠心病患者行ＰＴＣＡ＋ｓｔｅｎｔ术前后ＱＴ离散度进行分析。男性４６例,女性１４例,平均年龄５７岁,患者为单支血管病变３６例,多支血管病２４例。本组对ＰＴＣＡ＋ｓｔｅｎｔ术前后同步３导联的标准１２导联心电图Ｑ