Renal interstitial pressure and tubuloglomerular feedback control in rats during infusion of atrial natriuretic peptide (ANP)

Atrial natriuretic peptide (ANP), injected at physiological concentrations, is known to induce both natriuresis and diuresis. It has been suggested by some investigators that these changes result from an increasing glomerular filtration rate (GFR), but others have been unable to demonstrate an increased GFR. The tubuloglomerular feedback (TGF) mechanism is an important regulator of GFR, and the sensitivity of TGF is decreased during ANP administration. Furthermore, resetting of TGF is, in most instances, related to changes in renal interstitial hydrostatic and oncotic pressures. It is also known that ANP may increase capillary permeability which may change renal interstitial pressure. The present study was performed to examine renal interstitial pressures and the TGF mechanism during ANP infusion. In accordance with previous studies, TGF sensitivity was found to be decreased. The tubular flow rate which elicited half the maximal drop in stop-flow pressure (P_sf) was increased from 18.5 to 25.7 nl min^-1. In contrast, ANP infusion resulted in a decreased interstitial hydrostatic pressure and an increased interstitial oncotic pressure. From previous experiments, such changes in interstitial pressures would be expected to increase TGF sensitivity. The changes in interstitial pressure cannot, therefore, directly explain the resetting of the feedback mechanism. In conclusion, the present paper shows a decreased renal net interstial pressure after intravenous administration of ANP.     

Does ageing have an effect on midbrain premotor nuclei for vertical eye movements?

Currently, there is debate in the clinical literature as to whether defects in vertical gaze are a consequence of normal ageing or a component of an underlying neurodegenerative disorder. Although pathological changes have been demonstrated in diseased subjects, no study to date has addressed the question of normal ageing effects. In this retrospective study, we examined 23 neurologically and pathologically normal subjects (age 18-91). Using an unbiased, frame-based sampling method, we quantified neuronal and glial cell densities in 10 young (<50) and 13 aged (>65) subjects in the rostral interstitial nucleus of the medial longitudinal fasciculus (riMLF), the key premotor substrate in the vertical gaze pathway. We found no statistically significant difference in neuronal density, glial cell density, or neuron-to-glial cell ratios between the young and the aged. We conclude, therefore, that neuronal loss, neuronal atrophy, or gliosis in the riMLF are not consequences of normal ageing.     

硫酸镁治疗新生儿重症肺炎的临床研究及对血气血镁的影响

目的　为探讨硫酸镁治疗新生儿重症肺炎的临床效果及对血气血镁的影响。方法　采用 96例新生儿重症肺炎患儿随机分成治疗组 4 8例 ,对照组 4 8例 ,治疗组加用硫酸镁 30～ 5 0mg/(kg·d)加入 5 %葡萄糖 2 0ml静滴 ,持续 1h ,疗程3～ 8d ,同时监测血气血镁。结果　治疗组总有效率 79.2 % ,对照组总有效率 5 0 .0 % (P <0 .0 1) ,硫酸镁在改善症状 ,消除肺部体征及缩短住院时间和提高治愈率等方面优于对照组 ,治疗组病死率下降 ,同时血气恢复正常优于对照组 ,血镁含量治疗前后无变化。结论　硫酸镁治疗新生儿重症肺炎疗效显著 ,未发现明显副作用。     

37例传染性非典型肺炎流行病学调查与讨论

目的了解传染性非典型肺炎(SARS)流行病学的特点,提出相应的预防和控制措施.方法采取现场调查、网上电子病历审查、电话询问等方法.结果37例SARS患者的治愈率为89.2%,病死率8.1%,有接触史患者占37.8%.由于执行了严格的消毒隔离制度,医院内无任何人员感染发病.结论SARS患者在年龄上以青壮年为多,职业类以商业餐饮食人员为多.     

全身麻醉插管术后院内获得性肺部感染探讨

全身麻醉气管插管术后下呼吸道感染具有较高发生率。分析５２６例手术时间超过４小时普外科病例，经ｕ检验发现全身麻醉气管插管术后患者肺部感染率明显高于持续性硬膜外麻醉术后患者，影响因素主要与全麻插管用具及麻醉机消毒情况有关，也与术前存在慢性阻塞性肺部疾患和术后保留气管插管有关。降低全麻术后肺部感染应重视无菌操作，尽可能对麻醉机管道进行常规消毒。     

雾化吸入对新生儿肺炎患儿血氧饱和度的影响

采用动脉血氧饱和度仪对５２例新生儿肺炎患儿，在雾化吸入治疗过程中的动脉血氧饱和度（ＳａＯ２）进行了监测，对比了吸氧与否对ＳａＯ２改变的影响。结查表明：与基础值比较，雾化吸入时患儿的ＳａＯ２显著下降（Ｐ＜０．０１），而雾化吸入同时吸氧者ＳａＯ２无明显变化（Ｐ＞０．０５），但两者比较具有显著性差异（Ｐ＜０．０１）。结果提示雾化吸入可使新生儿肺炎患儿ＳａＯ２下降；同时吸氧，对防止ＳａＯ２的下降有一定作用。     

MR monitoring of MR-guided radiofrequency thermal ablation of normal liver in an animal model

The purpose of this study was to determine the suitability of MRI to accurately detect radiofrequency (RF) thermoablative lesions created under MR guidance. In vivo RF lesions were created in the livers of six New Zealand White rabbits using a 2-mm-diameter titanium alloy RF electrode with a 20-mm exposed tip and a 50-W RF generator. This was performed using a 0.2T clinical C-arm MR imager for guidance and monitoring. Each animal was sacrificed and gross evaluation was performed. Histologic correlation was performed on the first two animals. The MR-compatible RF electrode was easily identified on rapid gradient-echo images used to guide electrode placement. A single lesion was created in each rabbit liver. Lesions ranged from approximately 10 to 17 mm in diameter (mean, 13.5 mm). T2-weighted and short T1 inversion recovery (STIR) images demonstrated lesions ranging in diameter from 12 to 18 mm (mean, 14.6 mm). Lesion dimensions determined from images closely correlated with those determined at gross examination with the discrepancy never exceeding 2 mm, for an r² value of .87. MRI performed at the time of MR-guided RF ablation accurately demonstrated created lesions. This modality may provide a new option for the treatment of local and regional neoplastic disease.     

RAPD法对肺炎克雷白杆菌的基因分型

为了探讨肺炎克雷白杆菌的基因分型，我们用煮沸法制备细菌基因组ＤＮＡ，进行随机引物－聚合物酶链反应，所有１８个肺炎克雷白杆菌菌株均产生了特异性的，可重复的扩增条带，提示：ＲＡＰＤ方法可用于肺炎克雷白杆菌的分型鉴定和进行分子流行病学研究。     

An Autopsy Case of Dermatomyositis with Rapidly Progressive Diffuse Alveolar Damage

A 47-year-old woman visited a clinic with dyspnea which had continued for two months and was followed by general fatigue and fever. Antibiotics were not effective. Edematous erythema occurred on her face, elbows, knees and feet, and she entered our hospital. A skin biopsy revealed interface dermatitis with severe edema and mucinosis in dermis. Diffuse bilateral infiltration was observed in the chest X-ray, and laboratory findings showed increased LDH, GPT, GOT and CPK. No antinuclear factor was detected. Her respiratory condition rapidly worsened, and she died eight days after hospitalization in spite of corticosteroid pulse therapy. The autopsy revealed that the main cause of death was diffuse alveolar damage (DAD). Interstitial pneumonia related to dermatomyositis is not histologically uniform; the response to the therapy depends on its histological type. The patients with dermatomyositis who have poor prognosis are clinically characterized by acute onset with general symptoms and less pronounced muscle weakness; they generally show DAD in their lungs. We need to establish a simple method for distinguishing histological types of interstitial pneumonia and adequate therapy for each one.