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31.
Chromogenic ionophore-based methods for spectrophotometric assay of sodium and potassium in serum and plasma 总被引:1,自引:0,他引:1
A Kumar E Chapoteau B P Czech C R Gebauer M Z Chimenti O Raimondo 《Clinical chemistry》1988,34(9):1709-1712
We report spectrophotometric methods for quantifying sodium and potassium in serum and plasma without sample pretreatment or solvent-extraction steps. The methods are based on novel chromogenic ionophores characterized by molecular structures highly preorganized for binding, which result in exceptionally high sensitivity and selectivity (negligible responses to sodium at 80 to 200 mmol/L in the potassium assay and to potassium at 0 to 10 mmol/L in the sodium assay). The within-run imprecisions are comparable with those for ion-selective electrodes (for K, 1.0% at 4.5 mmol/L; for Na, 1.1% at 136 mmol/L); the analytical range is 2-10 mmol/L for potassium, 80-170 mmol/L for sodium. The results for greater than 100 patients' samples correlated well with results obtained with ion-selective electrodes (r = 0.99 for K, 0.97 for Na). The ready-to-use aqueous reagents will be available under the trade name of ChromoLyte for use with Technicon's RA family of clinical analyzers. 相似文献
32.
An increase in the number of cases of tuberculosis, especially in children, has been observed recently. Post-vaccination conversion rate in babies immunised with BCG was assessed. Sensitization was detected as early as 4 weeks after BCG inoculation. Although 84.2% had physical evidence of BCG inoculation only 69.8% had developed detectable sensitization to the tubercle bacilli as shown by the Mantoux test. 相似文献
33.
In 1985 an outbreak of ornithosis affected 13 of 80 (16%) workers in a duck-processing plant. New employees were three times more likely to become cases than established employees. The highest attack rate was in those on the production line. Following the outbreak, an occupational health scheme was set up to monitor the health of new recruits to the company. Serological evidence of recent infection was demonstrated in 18 of 37 (49%) new employees tested in the first 3 months of employment. Five (14%) also had clinical evidence of ornithosis. Veterinary investigation of the ducks demonstrated a high proportion with asymptomatic chlamydial infection. It is suggested that ornithosis may be more common in duck processors than is currently supposed. Strategies to reduce occupational risks are discussed. 相似文献
34.
Spleen sizing by ultrasound in polycythaemia and thrombocythaemia: comparison with SPECT 总被引:3,自引:1,他引:2
M. Messinezy L. M. MacDonald T. O. Nunan N. B. Westwood S. Chinn & T. C. Pearson 《British journal of haematology》1997,98(1):103-107
Detection of non-palpable early splenic enlargement may aid diagnosis of primary polycythaemia (PP) and primary thrombocythaemia (PT). In this study linear spleen sizing by ultrasound has been compared with spleen volume estimation by single photon emission computerized tomography (SPECT) in 26 patients. Spleen length by ultrasound correlated well with SPECT volume estimation.
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
Ultrasound spleen length was also measured in 60 normal control subjects where the upper limit of the 95% reference range was 11.6 cm. Changes in spleen length with both age and body weight were substantial and overshadowed the imperfect reproducibility of this method. Therefore, interpretation of an individual's measured spleen length should be in relation to that predicted for adults of the same age and weight, particularly at the extremes of the younger, heavier patients and also the older, lighter patients.
Ultrasound spleen lengths of different patient groups (21 PP, 26 PT, 17 idiopathic erythrocytosis, 12 secondary polycythaemia, nine apparent polycythaemia) were compared both using the measured overall reference range and the differences from the values predicted for their age and weight. The comparison showed that almost all patients with PP whose spleens were not palpable had spleen lengths greater than the upper limit for the normal control group, but separation from the other patient groups was incomplete.
Detection of non-palpable splenomegaly by ultrasound length should remain a 'minor' criterion amongst the 'proposed modified diagnostic criteria' of PP. 相似文献
35.
36.
Most authors consider the principal advantage of FG anastomoses (compared to microsurgical anastomoses) to be shorter operating time, reduced surgical trauma to oviduct stumps, and absence of tissue ischemia. These features promote reparative regeneration and decrease adhesion formation, resulting in complete recanalization of fallopian tubes. To date, the majority of work on FG is confined to the experimental development of surgical techniques. Investigations in reconstructive gynecological surgery are quite uncommon. The physical properties of FG and the positive results of available experimental studies suggest that further development of surgical techniques using FG in obstetrics and gynecology is worthwhile. 相似文献
37.
Sustained eosinophil cationic protein release into tears after a single high-dose conjunctival allergen challenge 总被引:1,自引:0,他引:1
P. G. MONTAN M. VAN HAGE-HAMSTEN O. ZETTERSTRÖM† 《Clinical and experimental allergy》1996,26(10):1125-1130
Background The appearance of eosinophils is a hallmark sign of the allergic late-phase response (LPR). Eosinophil cationic protein (ECP), a readily measurable product released from activated eosinophils, has so far not been evaluated in the ocular LPR. Objective Two sets of trials were performed in order to investigate changes of local and systemic eosinophil activity and their possible link with symptoms and hyper-reactivity in the allergic LPR in the eye. Methods In the first experiment, ECP was analysed in tears and serum and the clinical reaction was evaluated during a 72-h time–course after a single, high-dose allergen challenge out of season in one eye of 15 pollen-sensitized volunteers. In a second experiment, the hypothesis of an increased clinical response to an allergen challenge in an eye that had been provoked with allergen 48h previously was tested in nine sensitized individuals. Results In the first experiment, symptoms at 10 min and 2, 4, 6, 8 and 24 h significantly exceeded base line scores of the challenged eyes. Tear ECP was significantly elevated in challenged eyes compared to contralateral eyes at 6, 8 and 24 h. In addition, symptoms and ECP release correlated significantly at the 24-h evaluation. Serum ECP remained unchanged throughout the study period. In the second experiment, conjunctival hyperreactivity 48h after an allergen challenge was not confirmed. Conclusion ECP secretion occurs in the experimental ocular LPR and is in part associated with the magnitude of the clinical reaction, which suggests a truly pathogenic role of the activated eosinophil in pollen-induced allergic conjunctivitis. 相似文献
38.
39.
Recurrent erosion 总被引:1,自引:0,他引:1
40.
Electrocardiographic symptoms were evaluated in 53 patients with an additional left-ventricular chorda (ALVC), detected by two-dimensional echocardiography. Signs of early ventricular repolarization (EVR) were identified in 45 (84.9%) patients. A transverse ALVC was more common in EVR-free patients (87.5%), as compared to patients with ALVC + EVR combinations (51.1%; p less than 0.05). 相似文献