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31.
32.
Jonathan C. Craig Les M. Irwig James Christie Albert Lam Ella Onikul John F. Knight Premala Sureshkumar L. Paul Roy 《Pediatric nephrology (Berlin, Germany)》1997,11(4):455-459
Variability in the interpretation of micturating cystourethrography by paediatric radiologists for the diagnosis of vesicoureteric
reflux in children was evaluated. All 265 micturating cystourethrograms (MCUs) that were available from 304 consecutive children
aged 0.5 – 61 months – who were investigated after their first urine infection between 1993 and 1995 as part of a prospective
cohort study – were selected for interpretation. Three experienced paediatric radiologists from the same department independently
interpreted the MCUs according to the grading system of the International Reflux Study in Children, from grades 0 to V, with
the presence of intrarenal reflux also noted. Apart from being informed that urine infection was the indication for the MCU,
no other clinical information was given to the radiologists. The indices of variability used were the percentage of agreement
and the kappa statistic, expressed as a percentage. Both measures were weighted with integers representing the number of categories
from perfect agreement. Disagreement was analysed for children and kidneys. For the diagnosis of vesicoureteric reflux in
individual patients, including grade, the percentage of agreement was 96% – 97% (kappa 90% – 91%) and the weighted percentage
of agreement was 96% – 98% (weighted kappa 93% – 94%). The same high level of agreement was present for individual kidneys,
with a percentage of agreement of 97% – 98% (kappa 89% – 92%) and a weighted percentage of agreement of 98% – 99% (kappa 94% – 95%).
There was near perfect agreement in the interpretation of radiological micturating cystourethrography among three experienced
paediatric radiologists for the diagnosis and grade of vesicoureteric reflux. Any variations in the medical care of children
suspected of having vesicoureteric reflux are not explained by differences in the reporting of this diagnostic test.
Received June 19, 1996; received in revised form November 1, 1996; accepted December 6, 1996 相似文献
33.
Epidural abscess is a well-recognised but rare complication of epidural catheter placement. We have found only five previous reports of epidural abscess from noncatheter-related administration of steroids and/or local anaesthetic. We describe a further case which led to critical illness and emphasise the association between diabetes mellitus and epidural infection. 相似文献
34.
35.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
36.
37.
Very low maternal serum alpha-fetoprotein (MSAFP) levels (less than 10 ng/mL) are known to be associated with non-viable pregnancies, including conditions such as fetal death, molar pregnancies, and non-pregnancies. There has not been agreement, however, as to whether very low MSAFP levels indicate already existing fetal deaths or are actually predictive. We analysed 230 pregnancies with MSAFP levels less than 10 ng/mL from among 15,807 women (1.5 per cent) screened consecutively during a three-year period and identified 26 non-viable pregnancies, 22 of which were diagnosed sonographically as part of the screening process (17 missed abortions, 3 blighted ova, 2 non-pregnancies). Furthermore, 20 of these 22 pregnancies were associated with essentially undetectable MSAFP levels (less than 5 ng/mL). Our data indicate that pregnancies with MSAFP values less than 5 ng/mL are the group most strongly associated with fetal non-viability and that very low MSAFP values are not strongly predictive for fetal death. 相似文献
38.
J Stolk P Davies J A Kramps J H Dijkman J J Humes W B Knight B G Green R Mumford R J Bonney W A Hanlon 《American journal of respiratory cell and molecular biology》1992,6(5):521-526
We have studied the relative efficacy of antileukoprotease (ALP) and alpha 1-antitrypsin (alpha 1AT) to inhibit the degradation of substrate by polymorphonuclear leukocytes (PMN) attached onto a fibrinogen matrix. PMN elastase activity was assayed by radioimmunoassay of a specific 21-residue cleavage product from the amino terminus of the A alpha chain, A alpha (1-21), of fibrinogen. The adherence of PMN (1.0 x 10(6)) to a fibrinogen matrix was facilitated by incubation with recombinant tumor necrosis factor-alpha (1 nM). Subsequently, the cells were exposed to inhibitors before stimulation with cytochalasin B and formylmethionyl-leucylphenylalanine. Under these conditions, ALP inhibited A alpha (1-21) formation with an IC50 of 85 +/- 30 nM and alpha 1AT gave an IC50 of 220 +/- 98 nM (mean +/- SD). The effect of oxidant production on A alpha (1-21) formation was evaluated by comparing the effect of PMN from normal subjects with PMN from subjects with X-linked NADPH oxidase deficiency. Stimulation of PMN from the latter subjects in a similar fashion as described above resulted in the formation of 40 +/- 4 pmol/ml A alpha (1-21), or approximately twice the amount seen with cells from normal subjects. Preincubation with ALP or alpha 1AT in a concentration range between 10 to 900 nM resulted in an IC50 of 50 +/- 13 nM for ALP compared with 150 +/- 21 nM for alpha 1AT. Both inhibitors are more effective to prevent fibrinogen degradation caused by chronic granulomatous disease (CGD) PMN than by normal PMN despite the fact that CGD PMN generated more A alpha (1-21) than did normal PMN.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
39.
The interaction of normal lymphocytes and cells from lymphoid cell lines: II. Variations relating to cell line source and lymphocyte donor 下载免费PDF全文
Irradiated LCL cells from several sources activated the blood lymphocytes of a panel of donors. Individual differences were present but were small. Stimulated blood lymphocytes were more potent activators (after X-irradiation) than small lymphocytes in a one-way mixed lymphocyte reaction, indicating that the state of metabolic activity of the `stimulating' lymphocyte affects the level of activation achieved. However, LCL cells incubated for several days after irradiation had not lost stimulatory capacity. Lymphocytes of pigs, rabbits, rats and mice were much less responsive than human lymphocytes. The response of animal lymphocytes generally varied with the species of origin of the serum used in the cultures. 相似文献
40.
The in vitro transformation of thymocytes and lymphocytes from humans, rabbits and guinea-pigs and from thymomas 总被引:1,自引:5,他引:1 下载免费PDF全文
Stella Knight J. Bradley J. J. Oppenheim N. R. Ling 《Clinical and experimental immunology》1968,3(4):323-341
The response of human, rabbit and guinea-pig thymocytes in culture to blastogenic stimulants such as phytohaemagglutinin (PHA) and staphylococcal filtrate (SF) was usually considerably less than that seen with equivalent numbers of peripheral blood and lymph node lymphocytes. 相似文献