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771.
A 47-year-old woman with a 15-year history of Crohn's disease (CD) developed an adenocarcinoma of the duodenum. The preoperative diagnosis was suspected on radiologic and endoscopic examination and confirmed histologically.  相似文献   
772.
Staphylococcus aureus plays an important role as a bacterial pathogen after traumatic injury. The majority of isolated strains produces alpha-toxin, a 33-kDa protein, with membrane-damaging and lethal effects. The central nervous system (CNS) has been considered as the possible target for the lethal action of this toxin. A transfer of alpha-toxin across an intact blood-brain barrier (BBB) is however unlikely. The aim of the present study was to determine if alpha-toxin is accumulated in CNS regions which lack the BBB function. The distribution of alpha-toxin after intravascular injections, in normal mice and rats as well as in rats subjected to ventral root replantation, was assessed using immunogold technique. The results show that, although alpha-toxin does not cross the BBB, alpha-toxin-like immunoreactivity could be detected in the area postrema and at the optic nerve-retinal junction. Extravasation of alpha-toxin was also shown to occur in the spinal cord even 22 months after ventral root replantation. This finding suggests that axon regeneration after ventral root replantation takes place in a macromolecular environment which is totally different from the normal CNS. The implications of vascular spread of alpha-toxin to regions devoid of BBB function are discussed in relation to the bacterial infections which might complicate severe spinal injuries.  相似文献   
773.
774.
Dichloromethylene diphosphonate (Cl2MDP), an inhibitor of osteoclast-mediated bone resorption, lowers serum calcium in hypercalcemia associated with malignancies and with primary hyperparathyroidism. We have evaluated the effectiveness of Cl2MDP in three patients who had multiple osteolytic bone metastases due to breast cancer and coincident primary hyperparathyroidism and who refused neck exploration. Cl2MDP was added to the tamoxifen treatment and was given orally at a dose of 1600 mg/day for 12 months. All patients had a reduction in serum calcium level which was accompanied by a decline in the fasting urinary calcium and hydroxyproline excretion. Administration of Cl2MDP was not associated with any changes in parathyroid hormone levels. New bone metastases were observed neither during the treatment nor in the follow-up period. No side effects were observed.  相似文献   
775.
The pharmacokinetic and pharmacodynamic properties of a new multiple-unit, controlled-release (CR) formulation of metoprolol1 (metoprolol succinate, 95 mg once daily), which has almost constant (zero-order) release properties over most of a 24-h dose interval, have been compared with those of conventional metoprolol tablets (metoprolol tartrate, 100 mg once daily and 50 mg twice daily), in 12 healthy male volunteers.The steady-state plasma concentrations of metoprolol after five days of treatment varied less throughout the day with the CR than with the conventional formulation. This was associated with a considerably lower peak plasma concentration and the achievement of a significantly higher plasma concentration at the end of the dose interval.  相似文献   
776.
We present a case of a testicular germ-cell metastasis in the seminal vesicle. Diagnostic imaging with transrectal ultrasonography (TRUS), CT, and MRI was performed. This case emphasizes the role of MRI in the evaluation of patients with pathology in the pelvic region. Received 5 June 1996; Accepted 15 July 1996  相似文献   
777.
Myophosphorylase deficiency impairs muscle oxidative metabolism   总被引:1,自引:0,他引:1  
We studied oxidative metabolism during bicycle exercise in 4 patients with myophosphorylase deficiency. Maximal oxygen uptake (VO2max) was low (14.0 +/- 1.4 ml X kg-1 X min-1, mean +/- SE) compared with that in normal subjects (37.7 +/- 1.9; n = 12) and patients with myalgia (24.9 +/- 1.8; n = 10). Carbohydrate oxidation, as estimated by the respiratory exchange ratio (R), was low relative to workload (max R, mean +/- SE: McArdle's disease, 0.96 +/- 0.02; normal subjects, 1.13 +/- 0.02; myalgia, 1.09 +/- 0.02). Intravenous glucose administration increased maximal oxygen uptake about 20% in those with McArdle's disease, but both VO2max and R remained lower than in control subjects. These findings suggest that the capacity for dynamic exercise in McArdle's disease is limited by the availability of oxidative substrate, and indicate that blood glucose is unable to substitute fully for muscle glycogen as an oxidative fuel. We also found that exercise cardiac output (Q) was excessive relative to oxygen uptake in affected patients (delta Q/delta VO2, mean +/- SE: McArdle's disease, 11.6 +/- 1.7; normal subjects, 4.8 +/- 0.2; myalgia, 5.6 +/- 0.2). This hyperkinetic circulation in exercise may serve to increase the delivery of blood-borne oxidative substrate to working muscle.  相似文献   
778.
The serotoninergic innervation of the dorsal column nuclei (DCN) was investigated in cats and owl monkeys (Aotus trivirgatus) with immunohistochemical methods. A dense network of serotonin-immunoreactive fibers was present in the reticular regions of DCN in cats, and in the pars triangularis of the cuneate nucleus and the peripheral and caudal regions of the gracile nucleus in owl monkeys. The cat's cluster regions and the monkey's rotund regions were more sparsely innervated. Electron microscopic examination showed that the labeled fibers were thin and unmyelinated. Vesicle-containing, terminal-like structures were small. They were in contact with dendrites, other terminals and cell bodies, but synapses were rare. The results demonstrate that the serotoninergic projection to the DCN in both cats and owl monkeys is heterogeneously distributed in a pattern that is faithfully related to the cytoarchitectonic subdivisions of the DCN. The densely innervated reticular regions in the DCN of cats and the corresponding regions in monkeys are predominantly involved in the processing of sensory information to the cerebellum, either directly, or indirectly through projections to the inferior olive, pontine gray, tectum, pretectum, red nucleus, or zona incerta. Thus, the present findings suggest that the serotoninergic innervation of the DCN is primarily related to the DCN's involvement in motor functions. © 1993 Wiley-Liss, Inc.  相似文献   
779.
Imipenem and the renal enzyme inhibitor MK 0791 (dehydropeptidase-I) were tested separately and in a 1:1 combination to delineate their effects on granulocyte functioning. Each component, as well as the combination product, was found to increase granulocyte adherence and chemotaxis at therapeutic concentrations. Phagocytosis and chemiluminescence were not found to be significantly altered by any of the drug combinations.  相似文献   
780.
Exercise testing in men with significant left main coronary disease   总被引:1,自引:0,他引:1  
The exercise tests of 26 male patients with significant left main disease were compared with those of 51 patients with three-vessel disease and 38 patients with two-vessel disease. Exercise-induced ischaemia (chest pain and/or greater than 1 mm ST segment change) occurred in 100 per cent of left main, 69 per cent of three-vessel, and 45 per cent of two-vessel disease patients. Though the mean peak work load was significantly higher in the two-vessel disease group than in those with three-vessel of left main disease, there was a wide overlap between groups. No intergroup differences were found in mean peak heart rates. In patients taking propranolol, no differences in mean peak work loads and heart rates were seen. The study showed that the absence of an exercise-induced abnormal electrocardiographic response virtually excludes left main disease. As judged by exercise performance, the presence of left main disease did not correlate with the severity of the patient's symptomatology. Propranolol did not influence the frequency of an ischaemic response in patients with left main or three-vessel disease.  相似文献   
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