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PURPOSE: Our goal was to assess the role of MR cisternography in the examination of patients with suspected CSF rhinorrhea. METHODS: MR cisternography was performed as a heavily T2-weighted fast spin-echo study with fat suppression and video reversal of the images in 37 patients over a 3-year interval. Twenty-four of the patients subsequently had exploratory surgery for fistula. Statistical analysis of the surgical results was compared with the findings at MR cisternography. RESULTS: MR cisternography showed significant correlation with surgical findings, with sensitivity, specificity, and accuracy of 0.87, 0.57, and 0.78, respectively. CONCLUSION: MR cisternography proved to be an accurate diagnostic imaging technique in the evaluation of suspected CSF rhinorrhea.  相似文献   
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A case of acute renal failure is reported in which renal function returned after surgical correction of renal artery stenosis to the sole functioning kidney. Acute renal failure associated with renal vascular lesions is reviewed. Although often clinically apparent vascular obstruction may be asymptomatic and should be considered in cases of prolonged acute renal failure.  相似文献   
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A 3-year-old Latin female is reported with a terminal deletion of the No. 1 chromosome, karyotype formula 46, XX, del(1) (q43). Principle clinical features include: Anatomic - microcephaly; bilateral, convergent strabismus; epicanthus; brachycephaly; bulbar nose; sparse hair; partial soft tissue syndactylism between 2nd and 3rd fingers which are slightly tapered; whorls on all 10 fingers; mild prognathism; solitary kidney; vaginal stenosis; vesicoureteral reflux; asymmetric feet; and subluxation of peroneal tendons around the fibula with severe pronation and heal valgus deformity. Neurologic - moderate motor and mental retardation; high-pitched, shrill cry; absent pincer grasp at 3 years; and grand mal seizures documented from 9 months of age.  相似文献   
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This work is concerned with the preparation of deep contacts for layered structures on GaAs and InP substrates. The advantages of laser technology suggested contact preparation by laser annealing. Results of laser technology optimization are reported and the procedure for contact preparation is described. Concrete deep contacts were produced on structures with a cap layer up to 250 nm thick. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Cytotoxic lymphocytes (CLs) induce caspase activation and apoptosis of target cells either through Fas activation or through release of granule cytotoxins, particularly granzyme B. CLs themselves resist granule-mediated apoptosis but are eventually cleared via Fas-mediated apoptosis. Here we show that the CL cytoplasmic serpin proteinase inhibitor 9 (PI-9) can protect transfected cells against apoptosis induced by either purified granzyme B and perforin or intact CLs. A PI-9 P1 mutant (Glu to Asp) is a 100-fold-less-efficient granzyme B inhibitor that no longer protects against granzyme B-mediated apoptosis. PI-9 is highly specific for granzyme B because it does not inhibit eight of the nine caspases tested or protect transfected cells against Fas-mediated apoptosis. In contrast, the P1(Asp) mutant is an effective caspase inhibitor that protects against Fas-mediated apoptosis. We propose that PI-9 shields CLs specifically against misdirected granzyme B to prevent autolysis or fratricide, but it does not interfere with homeostatic deletion via Fas-mediated apoptosis.  相似文献   
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The complexity of the spot patterns of two-dimensional electrophoresis gels made it necessary to use image processing techniques to analyze the gels. An important issue in the analysis is the detection and quantification of the protein spots. In this paper we describe a new technique to segment and model the different spots. For the segmentation of a gel into its different spot regions we apply a watershed technique, which is robust and efficient. For the quantification of the spots, a new spot model is constructed, based on diffusion principles. Besides the advantage of having a physical interpretation, the model is demonstrated to be superior to the commonly used Gaussian models.  相似文献   
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