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941.
Following i.v. administration of the hydrophilic drug bretylium (1) and the lipophilic hexylsalicylic acid (2) in rats the plasma levels of 2 were increased due to an increased intestinal reabsorption of 2. Under these conditions the biliary eliminated amount of 2 was 8 times higher than that following the administration of 2 alone. The eneteroheptic circulation of 2 was found to be interrupted following i.v. administration of 1 and 2 and additional oral administration of an anionic exchanger. Then the plasma levels of 2 were not influenced by 1. On other hand the plasma levels of 2 appear to be too low in order to influence those of 1.  相似文献   
942.
Cross-correlation analysis of septohippocampal neurons during theta-rhythm   总被引:5,自引:0,他引:5  
The activity from 55 septohippocampal neuron pairs was examined in rats anesthetized with urethane. In addition to the statistical characterization of the firing patterns of the recorded units, the functional interactions between pairs of neurons and between neurons and hippocampal theta (theta) waves were investigated with cross-correlation techniques. Pairs were classified according to the rhythmic or non-rhythmic discharge pattern of their neurons. (a) theta-Pairs were those in which both the medial septal (MS) and hippocampal (HPC) units were rhythmic (type 1 units). (b) Pairs with a rhythmic and a theta-related non-rhythmic unit (type 2 unit) were called mixed pairs. (c) Pairs composed of type 2 units were called type 2 pairs. theta-Pairs showed periodic cross-correlations and frequently fired with a phase difference which could change in different pairs. Mixed pairs also showed periodic cross-correlations although one of the units was non-rhythmic. Type 2 pairs showed non-periodic positive cross-correlations. Our data provide new information regarding the temporal relationship between MS and HPC rhythmic activities supporting the role of the MS in providing the afferent timing for the generation of theta-rhythm in the HPC.  相似文献   
943.
On 14 patients with acute leukemia and non-Hodgkin lymphoma autologous bone marrow transplantation (ABMT) was performed together with high dose cyclophosphamide and hyperfractionated total body irradiation. The radiotherapy was given at a total dose of 13.2 Gy distributed over eleven fractions of 1.2 Gy and four days. All eleven patients transplanted in complete remission are alive, among them ten in unmaintained complete remission at a longest observation time of two years.  相似文献   
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Using traditional anatomical and histological methods, the muscle envelope of the pharynx-esophagus junction was investigated in humans and dogs. In the upper (cranial) portion of the esophagus of man and dogs, an inferior anatomical sphincter was detected which histologically can be referred to the group of rhabdo-sphincters. The upper esophageal sphincter is a purely esophageal structure which in man is located at a distance of 25-30 cm from the maxillary incisors. In adult humans, it is 25-30 mm long and is situated obliquely to the long esophageal axis. The posterior semicircle of the sphincter is located higher than the anterior one. In the area of the upper esophageal sphincter the esophageal wall is of different thickness. Due to the muscle envelope and submucous membrane of the base, the right wall is 1.7-2.0 times thicker than the left, anterior or posterior wall. The data obtained from fiber esophagoscopy of patients and electromyography of the pharynx-esophagus junction of dogs have shown that the upper (cranial) esophageal sphincter control food passage from the pharynx to the esophagus and prevents food reflux to the laryngopharynx, protecting airways from aspiration.  相似文献   
948.
Methods for assessing neurological disturbances in the diagnosis of the hand-arm vibration syndrome are described. The clinical examination should comprise a careful history of symptoms and vibration exposure and a consideration of neurological signs known to be associated with vibration exposure. There is as yet no etiologic diagnostic method for vibration-induced neurological lesions. The best method is a relevant clinical examination as described, in combination with a quantitative assessment of sensory modalities (such as the vibration perception threshold) and an electroneuromyographic test.  相似文献   
949.
Coronary revascularization using percutaneous coronary intervention (PCI) has rapidly developed in the past 2 decades and its technical and pharmaceutical improvements may avoid bypass surgery in many situations. The use of drug-eluting stents (DES) challenges the classic indications for bypass surgery and shifts them toward PCI, with the need for a critical appreciation of procedure- and patient-related risks. Furthermore, invasive measures such as intravascular ultrasound or pressure wire allow lesion-specific and immediate therapeutic decisions. This overview summarizes the actual potential of coronary intervention. To be aware of potentials and limitations may help the non-interventionalist to advise his patient and to choose the appropriate treatment.  相似文献   
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