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951.
The authors describe an original application of real time transducers--initially intended for intracavitary sonography--in thoraco-abdominal scanning. The stic-form probe can be easily slipped under the patient. It is then possible to realize a scan with an upward beam. In the postero-anterior scan, the patient is placed in a supine position. He is motionless. We achieve a better visualization of the liquid collections, since their accumulation is declivious. The method allows a wider sonographic window for thoraco-abdominal and diaphragmatic investigation in sonography. 相似文献
952.
The impact of percutaneous transluminal angioplasty on the management of peripheral vascular disease 总被引:1,自引:0,他引:1
J B Anderson A P Wolinski I P Wells D C Wilkins B P Bliss 《The British journal of surgery》1986,73(1):17-19
Percutaneous transluminal angioplasty is a well established technique with wide application, but its place in the overall management of peripheral vascular disease is not well defined. This study compares similar groups of patients with peripheral vascular disease in 1981 and 1984, before and after the introduction of the technique to a district general hospital. More patients are now being investigated and treated and this is almost entirely due to the availability of angioplasty. The rates for surgery have not changed. Percutaneous transluminal angioplasty should therefore be seen as a new and separate form of treatment for peripheral vascular disease, not necessarily influencing or replacing surgery, and requiring its own allocation of resources in accordance with the increase in the level of care afforded by the technique. 相似文献
953.
Ureteroscopic pyelolysis for pelviureteric junction obstruction 总被引:8,自引:0,他引:8
The development of endourological techniques for the treatment of upper urinary tract disease has concentrated mainly on the endoscopic treatment of upper urinary tract stones. The relief of pelviureteric junction obstruction (PUJ) by percutaneous pyelolysis has recently been reported and the use of the flexible uretero-pyeloscope has also been described. We describe the use of a rigid uretero-renoscopy to relieve strictures causing secondary pelviureteric junction obstruction in two cases. 相似文献
954.
Direct observation in vitro of how neuroblasts migrate: medulla and cochleovestibular ganglion of the chick embryo 总被引:4,自引:0,他引:4
The hypothesis that neuroblasts migrate in the nervous system by a locomotory process was tested experimentally. An in vitro preparation permitted direct observation of postmitotic cells migrating from the rhombic lip of the medulla and the anlage of the cochleovestibular ganglion. Cell locomotion was not seen. Instead migration was produced by elongation of a leading process, followed by translocation of the nucleus (perikaryal translocation). On the basis of comparisons with previous observations in situ, we propose that this represents a common mode of migration in the developing nervous system. Cell clusters were explanted from the rhombic lip at the developmental stage when they migrate from the ventricular zone to the acoustico-vestibular anlage in the medulla. Cells from the cochleovestibular ganglion were explanted after migration from the otocyst, but before ganglionic differentiation. Each neuroblast's migration route was formed by an elongating leading process ending in a growth cone. The growth cone attached to other cells and processes or ended freely on an acellular substrate. Nonneuronal cells usually migrated as has been described for fibroblasts, yet with some of the features of perikaryal translocation, but some nonneuronal precursor cells may migrate the way neuroblasts do. Neuroblasts did not migrate preferentially on the processes of nonneuronal cells, although the reverse could be observed. In fact a variety of interactions between migratory cells, neuronal and nonneuronal, were observed. The advantage of the experimental system described here is that one can observe cells migrating spontaneously at the times in development when they normally do so, while preserving the cellular populations present in situ. 相似文献
955.
Physiological analysis of simple rapid movements in patients with cerebellar deficits. 总被引:5,自引:3,他引:2 下载免费PDF全文
M Hallett A Berardelli J Matheson J Rothwell C D Marsden 《Journal of neurology, neurosurgery, and psychiatry》1991,54(2):124-133
Patients with cerebellar deficits made elbow flexion movements as rapidly as possible for three different angular distances. Electromyographic activity of biceps and triceps and the kinematics of the movements were analysed. Results were compared with those of normal subjects making both rapid and slow movements. In the patients, the first agonist burst of the biceps was frequently prolonged regardless of the distance or speed of the movement. The most striking kinematic abnormality was prolonged acceleration time. The pattern of acceleration time exceeding deceleration time was common in patients but uncommon in normal subjects. The best kinematic correlate of the duration of the first agonist burst was acceleration time. Altered production of appropriate acceleration may therefore be an important abnormality in cerebellar dysfunction for attempted rapid voluntary movements. 相似文献
956.
A D Mendelow 《Journal of neurology, neurosurgery, and psychiatry》1991,54(3):193-195
957.
R Menningen M Günther N B?nninghoff C D Stahlknecht I Kubitza J Kusche 《Agents and actions》1986,18(1-2):38-40
In the operative treatment of appendicitis the so called negative appendectomy is an important issue because of its increased morbidity. From the hypothesis that the intestinal diamine oxidase activity is a suitable marker of mucosal integrity, the distribution pattern of the enzyme in appendices histologically classified as inflamed or not inflamed was studied. Histologically apparent inflammation of the appendix was connected with a significant reduction of diamine oxidase activity. The determination of this enzymic activity may be a simple and sensitive test for mucosal inflammation of the appendix even at a very early state. This could reduce the rate of negative appendectomies and influence thereby risk-cost-benefit calculations. 相似文献
958.
959.
960.
A López Bernal D J Hansell S Alexander A C Turnbull 《British journal of obstetrics and gynaecology》1987,94(11):1052-1058
The production of progesterone from pregnenolone, of cortisol from cortisone and of prostaglandin E (PGE) under basal and arachidonic acid-stimulated conditions was measured in cells dispersed from chorion and decidua. The cells were obtained after delivery from four groups of women: following spontaneous labour at term (38-42 weeks gestation), at elective caesarean section at term before the onset of labour, after induced labour at term, and after uncomplicated preterm (27-36 weeks) labour. Chorionic cells had a high progesterone output with relatively low cortisol and PGE production, whereas decidual cells had a high cortisol and PGE production rate. Free arachidonic acid stimulated PGE production in both decidual and chorionic cells. There were no significant differences in either steroid or PGE production among the four groups studied. These data suggest that steroid dehydrogenase activity in choriodecidual cells is not related to the mode of onset of labour and that the increased prostaglandin production in intrauterine tissues associated with parturition is due to enhanced availability of arachidonic acid. 相似文献