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71.
In a prospective study intravenous urography (IVP) and abdominal ultrasonography (US) were compared in 100 consecutively admitted male patients with symptoms of infravesical obstruction. No pathology was found in 67 patients on IVP and in 61 patients on US. Both modalities disclosed 5 bilateral, 4 unilateral hydronephroses and one patient with contracted kidneys. IVP found 7 renal masses: one solid tumour, 2 "possibly solid" tumours and 4 "possibly cysts", whereas US found one solid tumour and 16 cysts. Both modalities detected 3 kidney stones, 5 bladder stones and 3 bladder tumours. It is concluded that "imaging" of the urinary tract is only indicated in cases of haematuria, elevated creatinine, history of renal calculous disease and other clinical suspicion of upper urinary tract disease. It is further concluded that US is preferable to IVP in this patient category due to (1) better characterization of renal masses, (2) the possibility of investigating the liver and the retroperitoneum in the same setting, (3) better evaluation of the prostate with respect to size, (4) better evaluation of the bladder, and (5) last but not least for economical reasons. However, bone metastases will be missed. 相似文献
72.
Marchand-Pauvert V Nielsen JB 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,142(3):402-408
In 16 human subjects, stimulation of the common peroneal nerve (CPN) was applied during walking and standing. The effect of the stimulation was evaluated from the rectified and averaged biceps femoris (BF) electromyographic (EMG) activity. In the swing phase of walking, the CPN stimulation evoked a suppression in the BF EMG in 12 of the subjects. In the early stance phase, the suppression was replaced by facilitation at a similar latency in 9 of the subjects. Of the other 3 subjects, in whom a suppression was observed during swing, a decrease in the suppression was observed in the stance phase in two of them. During a voluntary co-contraction of BF and tibialis anterior while standing, a suppression similar to that observed in the swing phase was observed. The thresholds of the suppression and facilitation were identical, suggesting that afferents of similar diameter were responsible. Cutaneous stimuli, which mimicked the sensation evoked by the CPN stimulation, but without activation of muscle afferents, did not produce similar effects in the BF EMG activity. It is suggested that the observed response and reflex reversal may reflect opening of an excitatory group I pathway in the early stance phase of walking with a concomitant shut-down of heteronymous group I inhibition. 相似文献
73.
Erik A. Richter Bente Sonne Kari J. Mikines Thorkil Ploug Henrik Galbo 《European journal of applied physiology》1984,52(3):346-350
Summary We have previously found that during exercise net muscle glycogen breakdown is impaired in adrenodemedullated rats, as compared with controls. The present study was carried out to elucidate whether, in rats with deficiencies of the sympatho-adrenal system, diminished exercise-induced glycogenolysis in skeletal muscle was accompanied by increased breakdown of triglyceride and/or protein. Thus, the effect of exhausting swimming and of running on concentrations of glycogen, protein, and triglyceride in skeletal muscle and liver were studied in rats with and without deficiencies of the sympatho-adrenal system. In control rats, both swimming and running decreased the concentration of glycogen in fast-twitch red and slow-twitch red muscle whereas concentrations of protein and triglyceride did not decrease. In the liver, swimming depleted glycogen stores but protein and triglyceride concentrations did not decrease. In exercising rats, muscle glycogen breakdown was impaired by adrenodemedullation and restored by infusion of epinephrine. However, impaired glycogen breakdown during exercise was not accompanied by a significant net breakdown of protein or triglyceride. Surgical sympathectomy of the muscles did not influence muscle substrate concentrations. The results indicate that when glycogenolysis in exercising muscle is impeded by adrenodemedullation no compensatory increase in breakdown of triglyceride and protein in muscle or liver takes place. Thus, indirect evidence suggests that, in exercising adrenodemedullated rats, fatty acids from adipose tissue were burnt instead of muscle glycogen. 相似文献
74.
Pathogenetical factors possibly responsible for recurrence of nontoxic goitre in a nonendemic area are evaluated. A group of 22 female patients admitted for surgical treatment of recurrent nontoxic goitre was compared with a control group of 86 female nontoxic goitrous patients not operated upon before. Preoperative serum baseline thyrotrophin levels in the recurrent goitre group were low normal and did not differ significantly from those in the control group. Circulating thyroid microsomal autoantibodies, thyroglobulin antibody titers, and the densities of lymphocytic aggregation in goitrous tissue did not differ significantly in the two groups. Thus, none of the parameters studied were likely explanations of regrowth of goitre. 相似文献
75.
The endurance during sustained contraction of elbow, flexors, elbow extensors, and back extensors was tested in 3 human subjects. The force level used was varied between ca. 15 and ca. 75% of maximal isometric strength (IS). The clearance of133Xe from contracting muscles was registered during and after the endurance test. In this way it was possible to determine whether muscle blood flow (MBF) was increased or had stopped during the contraction. Experiments with artificial ischaemia of the upper arm together with MBF measurements showed that MBF was of no importance for continuing sustained contractions above a certain force level, which was 50, 25, and 40% of IS for elbow flexors, elbow extensors and back extensors, respectively. However, the level where longer lasting (>15 min) sustained contraction is possible is directly related to MBF. These levels were 22, 15, and 20% IS for elbow flexors, elbow extensors, and back extensors, respectively. 相似文献
76.
Infection studies with canine distemper virus in harbour seals 总被引:1,自引:0,他引:1
V. Svansson M. Blixenkrone-Møller K. Skirnisson P. Have N. -I. Heje J. Nielsen E. Lund 《Archives of virology》1993,131(3-4):349-359
Summary Infection studies in harbour seal (Phoca vitulina) were conducted with the Snyder-Hill strain of canine distemper virus (CDV) that is virulent for dog and mink. The inoculated seals showed clinical symptoms which were to some degree similar to those observed in CDV infections of sensitive species of carnivores. Viral replication in lymphoid cells was followed by an extended period of immunosuppression. The results did not provide conclusive evidence for viral replication in surface epithelia of seals, and accordingly no spread of the infection to contact seals and mink was demonstrated. The pathogenicity of the infection did not increase upon a second viral passage in seal. The serological data showed that CDV-infected seals mounted an early virus specific antibody response. Overall, the results indicated that the harbour seal was not especially sensitive to CDV infection. The differences in the in vivo biological properties of CDV and PDV add to the distinction between these viruses at the genomic and antigenic levels. 相似文献
77.
Summary The size of the maximalH-reflex (H
max) was measured at rest and expressed as a percentage of the maximalM-response (M
max) in 17 untrained subjects, 27 moderately trained subjects, 19 well-trained subjects and 7 dancers from the Royal Danish Ballet. TheH
max/M
max was significantly larger in the moderately and well-trained subjects than in the untrained subjects but smaller in the ballet dancers. It is therefore suggested that both the amount and the type of habitual activity may influence the excitability of spinal reflexes. 相似文献
78.
79.
O'Brien SG Guilhot F Larson RA Gathmann I Baccarani M Cervantes F Cornelissen JJ Fischer T Hochhaus A Hughes T Lechner K Nielsen JL Rousselot P Reiffers J Saglio G Shepherd J Simonsson B Gratwohl A Goldman JM Kantarjian H Taylor K Verhoef G Bolton AE Capdeville R Druker BJ;IRIS Investigators 《The New England journal of medicine》2003,348(11):994-1004