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31.
Alterations in blood glucose levels are known to be involved in electrocardiogram changes. Various types of arrhythmias have been reported. We present here the case of an 81-year-old woman presenting with transient atrial fibrillation while being treated for hypoglycaemia with dextrose infusion, and finally developing a sinus rhythm. The presence of alterations in glucose blood levels should always be considered as a potential cause of transient atrial fibrillation.  相似文献   
32.
Venous leg ulcers derived from tissue destruction is the consequence of a chronic inflammatory process that produces pain and physical disability, diminishing quality of life in patients. In this work, Lassar ointment and lyophilized collagen‐polyvinylpyrrolidone were administered separated each on one half in the same ulcer to 9 patients at the beginning and every 4 days. On day 16, all patients were auto‐grafted with partial thickness skin. Granulation tissue and graft integration were assessed clinically during 3 months. Inflammatory infiltrate, type I and III collagens, elastic fibers, alkaline phosphatase as well as blood vessels were evaluated histologically or histochemically in biopsies taken at the beginning and 16 days after the local treatment. Clinically and morphologically, both treatments demonstrated appropriate granulation tissue promotion and optimal graft integration since the beginning. Nevertheless, in Lassar ointment treated group regionalization of alkaline phosphatase activity was observed, as well as the presence of granuloma in 2 of the 9 patients. In conclusion, Lassar ointment or lyophilized collagen‐polyvinylpyrrolidone are two different promoters of granulation tissue in venous leg ulcers, however Lassar ointment has the capability to produce granuloma and an exacerbated immune response; in consequence, ulcer recidivism could be present, may be due to mineral deposits in the wound.  相似文献   
33.
A series of 1153 fine-needle aspiration biopsies (FNAB) of breast masses obtained during the period 1985 to 1988 in one institution was examined. The following diagnostic accuracy values were found: sensitivity, 93.0%; specificity, 92.4%; predictive positive value, 93.7%; and efficiency, 92.8%. These results were compared with a previously published series for the period 1976 to 1984. The diagnostic accuracy values did not differ significantly between the two series.  相似文献   
34.
Submitral ventricular aneurysm is a thoroughly studied pathology but is not well known due to its rarity. Clinically, it is manifested by symptoms and signs of heart failure, mitral regurgitation and/or ventricular arrhythmias, and may be associated with thromboembolic phenomena and myocardial ischemia due to compression of the coronary arteries by the aneurysm. A rare complication of this type of aneurysm is rupture into the left atrium. Transthoracic echocardiography plays an important role in the definitive diagnosis of this pathology, although the role of transesophageal echocardiography in the evaluation of these patients is less known. We report a case of a submitral ventricular aneurysm complicated by rupture into the left atrium, which was diagnosed by transesophageal echocardiography.  相似文献   
35.
Background: Only limited data exist comparing differences in sensory function and responses to neural blockade in infant and adult rats. Therefore, the authors sought (1) to compare baseline thermal, proprioceptive, and postural responses in infant, adolescent, and adult rats; and (2) to compare the effects of sciatic nerve blockade on thermal, proprioceptive, and postural responses in infant, adolescent, and adult rats.

Methods: Infant, adolescent, and adult rats were evaluated for proprioceptive, thermal, and mechanical nociceptive and motor function before and after sciatic blockade using a detailed neurologic examination.

Results: Mechanical and thermal nociception were present in all rats, starting from age 1 day. The withdrawal reflex latency to pinch was rapid at all ages, whereas that reaction to thermal stimulus depended on both age and temperature. In contrast, the tactile placing response and hopping response were absent at birth and developed completely during the first 10 days of life. The extensor postural thrust was absent in the first 2 weeks of life and developed variably during the first 50 days of life. Sciatic blockade duration is shorter in infant rats than in adult rats receiving the same dose per kilogram. A brief halothane general anesthetic at the time of sciatic injection in infant or adult rats does not alter the duration of blockade.  相似文献   

36.
Advances in processing of surface myoelectric signals: Part 1   总被引:10,自引:0,他引:10  
During sustained voluntary or electrically elicted muscle contractions the surface myoelectric signal is nonstationary and it undergoes progressive changes reflecting the modifications of the motor unit action potentials and their propagation velocity. In particular, during sustained electrical stimulation, the evoked signals show progressive amplitude, time scaling and shape modification. The quantitative evaluation of these changes is important for non-invasive muscle characterisation and may be performed in either the time or frequency domain using parametric and nonparametric spectral analysis as well as alternative methodologies. The paper introduces the detection techniques, reviews and compares the methods of spectral estimation based on FFT and autoregressive models, and discusses their applications and limitations in extracting information from the surface myoelectric signal with particular regard to myoelectric manifestations of localised muscle fatigue during sustained contractions.  相似文献   
37.
Several sets of data suggest that specific classes of anti-DNA antibodies could be implicated in the genesis of glomerular lesions in SLE. The goal of this work is to investigate if this pathogenic role could be related to the antibodies' genetic origin--from BALB/c or NZBxNZW/F1 mice--or to their physiological origin--induced either by DNA or by polyclonal B cell activation in normal mice. For this purpose, anti-DNA antibody hybridoma clones produced from different origins were subcutaneously injected in BALB/c or NZBxNZW/F1 female mice, followed by studies of immunological parameters and kidney lesions. Results concur that the induced anti-DNA antibodies can play a role in fatal disease development, related to clonal specificity but not to the way of stimulation which was either polyclonal B cell activation or DNA immunization. Also, they emphasize the possible very lethal role of serum circulating DNA.  相似文献   
38.
The effects of sedative-hypnotic doses of propofol on respiratory drive and pattern have not yet been extensively described. Repeated small boluses of propofol (0.6-0.3 mg.kg-1) were administered to ten ASA I patients undergoing carpal tunnel release using regional anaesthesia. Airway pressure, capnography and pneumotachography were continuously recorded. With respect to basal values, no significant variations of respiratory rate, minute volume, tidal volume, inspiratory and expiratory time, total expiratory cycle, Ti/Ttot, TV/Ti, P0.1, EtCO2 and blood gas analysis were observed. Low doses of propofol, to maintain conscious sedation of light sleep, have not been shown to cause respiratory depression.  相似文献   
39.
Metabolism of cysteine and cysteinesulfinate in rat and cat hepatocytes   总被引:1,自引:0,他引:1  
The metabolism of cysteine and cysteinesulfinate was studied in freshly isolated hepatocytes from fed rats and cats. In incubations of rat hepatocytes with cysteinesulfinate, the rate of hypotaurine plus taurine production was approximately the same as the rate of conversion of the 1-carbon of cysteinesulfinate to CO2. In contrast, no significant production of hypotaurine plus taurine occurred in incubations of cat hepatocytes with cysteinesulfinate. These data are consistent with the species difference in the activity of hepatic cysteinesulfinate decarboxylase, which converts cysteinesulfinate to hypotaurine. In incubations of either rat or cat hepatocytes with cysteine, no hypotaurine plus taurine production was detected. However, the 1-carbon of cysteine was converted to CO2 and the production of urea plus ammonia nitrogen was significantly increased over the rates observed in incubations of cells without substrate. Our results suggest that most cysteine oxidation by hepatocytes occurs by pathways that do not involve formation of cysteinesulfinate.  相似文献   
40.
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