Colour Doppler ultrasound assessment of the inferior vena cava in patients with Wilms' tumour

OBJECTIVE: To assess the diagnostic accuracy of colour flow Doppler ultrasound in diagnosing inferior vena caval (IVC) extension of tumour thrombus in patients with Wilms' tumour. MATERIALS AND METHODS: Over a 3-year period from June 1994 to June 1997, 74 patients with Wilms' tumour were referred to our institution. In this retrospective study we reviewed the preoperative colour flow Doppler ultrasound reports of 64 of these patients and compared the reports with the intra-operative findings in 51 patients who underwent surgery. RESULTS: Vena caval extension of tumour thrombus was present in 12 patients (18.7%) and in six of these patients (9.4%) there was also atrial extension of the tumour. Colour flow Doppler ultrasound correctly diagnosed IVC extension of tumour thrombus in nine patients and correctly predicted the cranial extent of the tumour thrombus in eight patients. CONCLUSION: Colour flow Doppler ultrasound has an overall positive predictive value of 73.4% in assessing IVC patency and correctly diagnosing IVC extension of tumour thrombus, in patients with Wilms' tumour. However, non-diagnostic ultrasound examinations can occur in over 20% of patients.     

Laparoscopic end-to-end aortobifemoral bypass with reimplantation of the inferior mesenteric artery

Background: Colic ischemia is a serious complication that can occur after abdominal aortic surgery. It has been described in two patients after laparoscopic aortic surgery. The goal of the current experiment was to determine the feasibility of inferior mesenteric artery (IMA) reimplantation during laparoscopic aortobifemoral bypass (LAFB). Methods: Six piglets were submitted to the laparoscopic approach according to the ``apron' technique previously described. The infrarenal aorta was clamped and an LAFB was performed using a dacron graft. The IMA was reimplanted in the body of the graft with a running 5-0 polypropylene suture. Results: Mean operation and dissection times were 282.5 min (range, 270–310 min) and 123 min (range, 110–140 min), respectively, with a mean blood loss of 108 ml (range, 80–150 ml). Aortic clamping and anastomotic times were 123 min (range, 110–135 min) and 33 min (range, 24–45 min), respectively. The IMA reimplantation took 55 min (range, 45–70 min). At autopsy, all anastomoses were patent with no stenosis nor leak. Conclusion: Laparoscopic IMA reimplantation during laparoscopic aortobifemoral bypass is feasible. Received: 10 July 1998/Accepted: 15 November 1998     

c-Fos expression in the auditory pathways related to the significance of acoustic signals in rats performing a sensory-motor task

Neuronal activity was established in the auditory pathways in relation to behavioural response and cognitive information processing during a sensory-motor acoustic learning. Rats were trained in three consecutive phases. The first phase was an association between an auditory stimulus and a food reward; the second phase a simple discrimination between two sounds of different frequency components, and the third phase a more complex discrimination involving both spectral and spatial sound dimensions. Auditory stimuli were bursts of complex sounds lasting 500 ms. Neuronal activity related to the behaviourally relevant stimuli was established in 20 "learning" rats undergoing this protocol, which were progressively sacrificed at the beginning, middle and end of each phase. For comparison, activity was also established in four "control" rats exposed to the same stimuli delivered pseudo-randomly, thus carrying no behavioural meaning. Neuronal activity was assessed immunocytochemically using the functional marker Fos. To establish a baseline, two rats were unexposed to controlled acoustic stimulation ("unstimulated" rats). In the superior olivary complex (SOC), inferior colliculus (IC) and medial geniculate body (MGB), the number of Fos-like immunopositive cells was comparable in "learning" and "control" animals, but higher than in the "unstimulated" rats. In the auditory cortex (AC), most prominently in the secondary area Te2, the number of Fos-like positive cells differed between "learning" and "control" rats, suggesting that the auditory cortical areas may be involved in the encoding of the behavioural significance of the acoustic stimuli.     

Defensive reactions are counteracted by midazolam and muscimol and elicited by activation of glutamate receptors in the inferior colliculus of rats

 The inferior colliculus is involved in conveying auditory information of an aversive nature to higher cortical structures. Gradual increases in the electrical stimulation of this structure produce progressive aversive responses from vigilance, through freezing, until escape. Recently, we have shown that microinjections of NMDA into the inferior colliculus mimic these aversive effects and that the neural substrates responsible for learned escape behavior in the inferior colliculus are regulated by GABA−benzodiazepine mechanisms. In the present study, we extend these observations showing that unlearned aversive responses are also depressed by muscimol and midazolam, both GABA-benzodiazepine agonists, and that microinjection of glutamate, an excitatory amino acid, into the inferior colliculus can trigger freezing responses. Electrical stimulation of the inferior colliculus of rats placed inside an open field allowed the determination of thresholds for the aversive responses, alertness, freezing and escape. Systemic administration (3 and 5.6 mg/kg) as well as microinjections into the inferior colliculus of the anxiolytic compound midazolam (10, 20 and 40 nmol) caused increases in threshold for these aversive responses. Similar results were obtained following microinjections of the GABA-A agonist muscimol (0.1, 1 and 5 nmol) into this brainstem structure. Microinjections of low doses of glutamate (5 nmol), presumed to activate mainly AMPA/kainate receptors, into the ventrolateral division of the central nucleus of the inferior colliculus of rats placed inside a circular arena induced aversive reactions, characterized by freezing responses. However, higher doses of glutamate caused no apparent effects. GDEE, an AMPA/kainate receptor antagonist, inhibited, whereas AP7, a NMDA receptor antagonist, did not influence these responses. It is suggested that GABA-benzodiazepine processes modulate the expression of defensive reactions in the inferior colliculus and that activation of fast-acting excitatory amino acid receptors in this midbrain region can trigger the initial steps of the defense reaction without eliciting the motor explosive behavior usually seen following the activation of NMDA receptors. Received: 13 May 1998 / Final version: 12 August 1998     

鼻腔神经部分切断术及下鼻甲粘骨膜下剥离术治疗变应性鼻炎18例临床分析

目的：观察鼻腔神经部分切断术和下鼻甲粘骨膜下血管神经离断术对变应性鼻炎的疗效。方法：对18例常年性变应性鼻炎患者进行鼻腔神经部分切断术与下鼻甲粘骨膜下血管神经离断术。所有病例随访12个月，评价其临床效果。结果：10例临床症状消失，体征明显改善；7例临床症状明显缓解，体征改善；1例无效。总有效率94．4％。结论：鼻腔神经部分切断和下鼻甲粘骨膜下血管神经离断术治疗常年性变应性鼻炎效果显著。     

包括腔静脉旁部的肝右尾叶及全尾叶切除

目的 探讨并总结包括腔静脉旁部肝尾叶切除的方法和经验。方法 分别采用右后途径和左侧途径行右尾叶和全尾叶切除；前者附加部分右后叶切除，后者可为单独全尾叶切除或附加左外叶或左半肝切除。结果 成功施行包括腔静脉旁部的肝尾叶切除13例，其中右尾叶切除7例，全尾叶切除6例；全组无手术死亡，术中、术后均无严重病发症发生；术后平均失血量为896.15ml，平均肝门阻断时间为25.40min，术后平均住院12.38天。结论 虽然解剖关系复杂，切除包括腔静脉旁部的肝尾叶安全可行。     

Venous complications after orthotopic liver transplantation

Complications involving the portal vein or the vena cava, are rare after orthotopic liver transplantation. We report on the incidence and treatment of venous complications following 1000 orthotopic liver transplantations in 911 patients. Twenty-six of the adult patients (2.7%) suffered from portal complications after transplantation, whereas complications of the vena cava were observed in only 17 patients (1.8%). Technical problems or recurrence of the underlying disease (e.g. Budd-Chiari syndrome) accounted for the majority of complications of the vena cava, whereas alteration of the vessel wall or splenectomy during transplantation could be identified as important risk factors for portal vein complications. In patients undergoing modification of the standard end-to-end veno-venous anastomosis of the portal vein due to pathological changes of the vessel wall, complications occurred in 8.3%, whereas only 2.4% of patients who received a standard anastomosis of the portal vein experienced complications of the portal vein. Furthermore, splenectomy during transplantation was also associated with an increased incidence of portal vein complications (10.5 vs. 2.2% in patients without splenectomy). Treatment was dependent on the signs and symptoms of the patients, and varied considerably between patients with portal vein complications and patients suffering from complications of the vena cava. Complications of the vena cava led to retransplantation in about one-third of the patients, whereas in patients with occlusion of the portal vein, retransplantation was necessary in only 15%, and more than half of the patients suffering from portal vein complications did not require any treatment at all. Usually, treatment of patients with portal vein complications only became necessary when additional complications such as arterial occlusion or bile duct injuries occurred.     

耳蜗急性纯音损伤后下丘及耳蜗核快速功能重组

实验比较高强度纯音损伤耳蜗局部区域前后，耳蜗背核及下丘接近损伤区边缘的神经元反应特性的改变。致损纯音的频率高于神经元的特征频率，且位于其兴奋区以外，所以不影响其兴奋性输入。结果发现此种纯音损伤在逾半数的神经元产生不同程度的去抑制效应，提示皮层的功能重组可能部分地起源于低位中枢的功能改变，下丘和耳蜗背核的抑制性神经网络具有相当程度的侧抑制组分。     

冬虫夏草及其伪劣商品的鉴别

冬虫夏草为名贵滋补药。明代即出口日本，现畅销国际市场，是中国传统的出口商品，享有极高的声誉。近年来国内外市场需求增大，而产量小，价格上扬，伪品、掺杂品增多。本文提出实用鉴别方法，以利保证冬虫夏草的质量。     

恶性上腔静脉综合征的坐位急诊放射治疗

目的回顾性分析不能常规卧位放疗的恶性上腔静脉综合征坐位急诊放疗的疗效。方法12例患者先坐位急诊放疗6MV—X DF300CGY／次／天；总剂量DT3000CGY／10次／2周。待症状明显缓解已基本能平卧后再改用常规卧位放疗补量DT3000—4000CGY／15—20次／3—4周。结果2周内总缓解率92％(11／12)，整个放疗计划完成后总有效率100％(12／12)。结论病情较重、病期较晚无法耐受化疗和常规卧位放疗的患者先坐位急诊放疗待症状部分缓解后再改常规卧位放疗能迅速改善症状，提高生活质量，为下一步治疗创造有利条件。