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Birnholz  JC 《Radiology》1986,158(3):805-807
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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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  
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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Summary: Purpose: The objective of this study was to compare the pharmacokinetics and cognitive effects of a new diazepam (DZP) rectal gel (Diastat®) with intravenously administered DZP.
Methods: Twenty healthy volunteers were enrolled in a single-blind, randomized, double-dummy, two-period, crossover study. Subjects received either 15 mg of DZP rectal gel or 7.5 mg of DZP by intravenous infusion. Blood samples for DZP and desmethyldiazepam analysis were obtained before the dose and from 3 min to 240 h after the dose. Heart rate and blood pressure were measured over the first 24-h period. Subjects also completed five repetitions of a neuropsychological test battery over the first 8-h period.
Results: Diazepam rapidly appeared in plasma after rectal administration, exceeding 200 ng/mL within 15 min and reaching an initial maximum of 373 ng/ml at 45 min and a second maximum of 447 ± 91.1 ng/ml at ∼70 min. The absolute bioavailability of DZP rectal gel was 90.4%. Subjects receiving intravenous DZP were less alert and performed less efficiently on the WAIS Digit Symbol test 6 min after the dose. Subjects receiving DZP rectal gel performed less well on the WAIS Digit Span test 1 h after the dose and required more time to complete the Letter Cancellation and Grooved Pegboard tests 1 and 2 h after drug administration.
Conclusions: Diastat® displayed rapid, consistent absorption and was well tolerated. Alterations in cognition were mild and dissipated within 4 h of drug administration. This new rectal drug-delivery system offers an easy, safe, and bioavailable method to administer DZP.  相似文献   
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