Panic disorder in cardiac outpatients

OBJECTIVE: Continuing the long history of interest in the relation of anxiety disorders to cardiovascular function and symptoms, this study investigated the level of anxiety and prevalence of panic disorder in cardiac patients and the possible associations between specific abnormal ECG results and a diagnosis of panic disorder. METHOD: Consecutive patients referred for ambulatory ECG recordings were assessed with the seven anxiety items of the Hospital Anxiety and Depression Scale. Then, 50 patients with scores higher than 8 (the anxious group) were interviewed with the Schedule for Affective Disorders and Schizophrenia--Lifetime Version Modified for the Study of Anxiety Disorders (SADS-LA). RESULTS: Of the 50 anxious patients (26 male and 24 female) interviewed with the SADS-LA, 62% (N = 31) met the DSM-III-R criteria for panic disorder. Patients with panic disorder had a higher mean maximal heart rate and a shorter P-R interval than patients without panic disorder. Unlike the patients without panic disorder, the patients with panic disorder showed no correlation between maximal heart rate and minimal P-R interval. CONCLUSIONS: The rate of panic disorder was high in the patients referred for ECG. Moreover, the prevalence of panic disorder was similar in the patients with and without ECG abnormalities, indicating that in anxious patients the presence of panic disorder does not rule out organic cardiac disease. On the other hand, the higher maximal heart rate and shorter P-R interval of the panic patients may be attributable to hypersensitivity of beta-adrenergic receptors in panic disorder.     

Contrast-enhanced magnetisation transfer MRI in metastatic lesions of the brain

Our purpose was to compare prospectively the sensitivity of contrast-enhanced magnetisation transfer (MT) MRI and gradient-echo (GE) T1-weighted images in metastatic disease of the brain. We studied 52 patients with brain metastases, using conventional T1-weighted GE and MT spin-echo (SE) images after the same standard dose of gadolinium. Axial 5-mm reconstructions of GE data were compared with 5-mm MT images in the same plane. Metastases were counted independently by two neuroradiologists. In 12 patients (23%) MT imaging showed more metastases than GE images (P = 0.03). We detected 68 more metastases with the former technique.     

Experimental fetal tracheal ligation reverses the structural and physiological effects of pulmonary hypoplasia in congenital diaphragmatic hernia

Infants with congenital diaphragmatic hernia (DH) and profound pulmonary hypoplasia are currently unsalvageable. The authors previously demonstrated that tracheal ligation (TL) accelerates fetal lung growth and reverses the pulmonary hypoplasia of fetal nephrectomy. The purpose of this study was to determine if the pulmonary hypoplasia of experimental DH could be similarly reversed and, if so, whether the resulting lungs would show better function than those of their DH counterparts. Eighteen fetal lambs were divided into three experimental groups of six animals each. In group 1, DH was created at 90 days' gestation. In group 2, DH was created at 90 days' gestation and TL performed during the same operation. Group 3 consisted of sham-operated controls. These animals were delivered near full-term, and their lungs analyzed by standard morphometric techniques. Ten additional fetal lambs were divided into two experimental groups of five animals each. In group 4, DH was created at 90 days' gestation. In group 5, DH was created at 90 days' gestation and TL performed 20 days later, at 110 days' gestation. These animals were pressure-ventilated via tracheostomy over a 2-hour period in which PaO2, PaCO2, and compliance were measured. Intratracheal pressure (ITP) was measured at the time of delivery in all groups. Upon retrieval, DH animals had abdominal viscera in the chest and small lungs; in contrast, DH/TL animals had the herniated viscera reduced from the chest by enlarged lungs. DH/TL lungs showed markedly increased growth, with significant increases in lung volume:body weight ratio (LV:BW; P = .0001), alveolar surface area (ALV.SA; P = .0001), and alveolar number (ALV#) (P = .0001) when compared with those of the DH or control group. This growth was associated with a normal maturation pattern based on histological appearance, normal airspace fraction, and normal alveolar numerical density. ITP in the DH/TL group was increased when compared with that of DH and control animals (P = .0001). Total lung DNA and protein were both elevated in the DH/TL animals (P = .0001). However, the DNA:protein ratio remained normal, suggesting lung growth had occurred through cell proliferation, not by hypertrophy. When ventilated over a range of settings, DH/TL lungs were more compliant (P = .0001) and achieved higher PaO2s (P < .003) and lower PaCO2s (P = .0001) than their DH counterparts. From these data, the authors conclude: (1) Experimental fetal DH produces hypoplastic lungs that are not capable of adequate gas exchange with conventional ventilation.(ABSTRACT TRUNCATED AT 400 WORDS)     

双重孔隙介质油藏中的吸渗排油作用

利用美国SSI公司研制的COMPN模拟软件对双重孔隙介质油藏一种重要的开采机理 吸渗排油进行了模拟研究,考察了一个基质岩块为四周裂缝所包围时.在驱动压力和毛管压力的不同平衡(驱动压力和毛管压力的相对大小)关系下的水驱油采收率和水驱油效率的变化规律.     

False aneurysm of the left ventricle and coronary aneurysms in Beh?et disease

A false left ventricular aneurysm and coronary artery aneurysm were discovered in a 29 year old patient with Beh?et's syndrome. The operation under cardiopulmonary bypass consisted of closing the neck of the false aneurysm by an endo-aneurysmal approach with a Gore-Tex patch. The coronary artery aneurysms were respected. There were no postoperative complications. Cardiac involvement is rare in Beh?et's syndrome (6%). The originality of this case is the association of two aneurysmal pathologies: the coronary and ventricular aneurysms due to the angiitis and the myocardial fragility induced by ischaemia.     

论滚齿加工在机测量技术

本文论述了滚齿在机测量中一些重要问题．应用偏心误差理论，揭示了以齿轮的齿顶、齿根和内孔为测量基准的测量齿距误差的实质，并对这三种基准进行了对比分析．指出了不同测量基准所测结果不同，若基准选择不当，有时产生“误收”或“误废”．论文针对当前滚齿在机测量装置存在问题．提出了一种滚齿在机１８０°转位双啮综合测量法，测量原理正确，结构简单，易于推广．     

混合型表面活性剂液膜法处理含酚废水研究

研究了兰－１１３Ｂ＝Ｓｐａｎ－８０－－煤油ＮａＯＨ液膜体系处理苯酚废水的最佳操作工用于对高浓度含酚废水进行处理，实验结果表明，混合型表面活性剂各项指标均较好，除酚效率可达９９％以上，对内相ＮａＯＨ的最佳浓度的确定给出了估算方法。     

Head scatter modelling for irregular field shaping and beam intensity modulation

Scattered radiation from within the treatment head can contribute significant dose to all parts of a radiotherapy treatment field. A multileaf collimator may be used to create an arbitrarily shaped field, and may also be used, under dynamic control, to modulate the beam intensity over the field. This method of intensity modulation is effectively a superposition of a large number of fields which have the same beam direction, but different shapes, and some of these shapes may have unusually small dimensions, particularly in the direction of the leaf movement. Two models for predicting the head scatter under these conditions have been investigated. These are a first-order Compton scatter approximation from the flattening filter, and an empirical fit to measured data using an exponential function. The first model only considers scatter from the flattening filter and has been applied to field sizes between 2 cm by 2 cm and 10 cm by 10 cm, where agreements are all within 1%. However it is not satisfactory at larger field sizes where small scatter contributions, from scattering sources other than the flattening filter, are integrated over large areas. The second model uses measured data between 4 cm by 4 cm and 30 cm by 30 cm to optimize the exponential function and is used to calculate the head scatter contribution for all field sizes. In this case good agreement is achieved over the full field size range, and hence this is a more generally applicable model. Results are presented for static irregularly shaped fields and intensity modulated beams created using a Philips multileaf collimator.