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11.
Ultrasound (US) can be used to visualize vertebral segments, suggesting a quantitative means of studying vertebral column growth in utero and thus a means of detecting developmental abnormalities. US images of the lumbar spine were obtained in 128 clinically normal fetuses between the gestational age of 11 through 41 weeks. A large-aperture, dynamically focused US system capable of regional magnification was used. Average lumbar spacing was calculated from distance between centrums of at least four lumbar bodies. The average distance between lumbar centrums increased nearly linearly throughout the second and third trimesters (r2 = 0.98). Enhanced anatomic display implies new capabilities for recognizing developmental abnormalities antenatally. 相似文献
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LN Weinberger MJ Zirwas JC English III 《Journal of the European Academy of Dermatology and Venereology》2007,21(2):156-162
Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed. 相似文献
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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
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Body JJ Richard V Pector JC Lemaire A Deshpande S Verheye E Borkowski A Meunier F 《Clinical nutrition (Edinburgh, Scotland)》1989,8(4):191-195
Infections constitute the main complication of parenteral nutrition, particularly in cancer patients, but prediction of catheter-related septicemias (CRS) has been little investigated. We have evaluated, in 200 consecutive episodes of parenteral nutrition (PN) in cancer patients, the factors contributing to infectious complications, and the predictive value of weekly blood cultures performed through the nutrition catheter. The median duration of PN was 22 days with a total of 5816 patient-days of PN, neutropenia (neutrophils < 1,000/mul) being present in 872 (15%). Catheters were placed either in a jugular vein (71% single-lumen silicone catheters, 18.5% double-lumen Hickman-Broviac catheters) or in a femoral vein (10.5%). We observed 62 episodes of septicemia of which 22 were CRS (11% incidence for the 200 cycles) and 40 were non-CRS (20% incidence); CRS were mostly due to Staphylococcus epidermidis (14 22 ). Neutropenic patients as a group did not suffer more CRS than non-neutropenic patients, but the risk of CRS was slightly increased when expressed per day of neutropenia (8 CRS/872 days vs 14 CRS/4942 days without neutropenia, P < 0.05). On the other hand, a femoral insertion site was associated with a much higher incidence of CRS (9 CRS/21 femoral catheters vs 13 CRS/179 jugular catheters, P < 0.0001). It was possible to evaluate 20 episodes of CRS for their predictability by weekly blood cultures: the sensitivity for detecting CRS due to Staphylococcus epidermidis was 67%, the specificity 92%, the negative predictive value 98% and the positive predictive value 36%. The simple and widely available procedure of routine surveillance blood cultures performed through the PN catheter should be further investigated, because it could help the clinician to determine the origin of recent fever, particularly to exclude CRS and avoid unnecessary removal of PN catheters. 相似文献
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