This study was performed to determine if there is a relationship between apparent diffusion coefficient (ADC) and cellularity of bone marrow of the posterior ilium. Four groups of various marrow cellularity underwent diffusionweighted echo-planar imaging: 1) adults with normal hypocellularity (21 patients); 2) adults with normal normocellularity (13 patients); 3) young children with normal hypercellularity (5 patients); and 4) adults with lymphomarelated hypercellularity (3 patients). In all adults, marrow cellularity was confirmed by uni-or bilateral bone marrow biopsies. In children, the iliac marrow was presumed hy- Index terms: MRI; bone marrow; diffusion-weighted EPI; marrow cellularity; ADC DIFFUSION-WEIGHTED MRI is a relatively new method to quantitatively image intravoxel incoherent motion (IVIM) in vivo, as introduced by Le Bihan et al (1). These motions include molecular diffusion of water and microcirculation of blood in the capillary network, perfusion (2). By means of a parameter termed apparent diffusion coefficient (ADC), quantification of IVIM is possible. The ADC calculation is based on the signal intensity of the original diffusion-weighted images with two different b factors. Diffusion-weighted MR imaging was recently introduced to evaluate vertebral bone marrow (3-5). Bauer et al (3) reported that pathologic compression fractures are of high signal intensity, whereas benign compression fractures are relatively hypointense. They speculated a decrease in the ADC, hypothesizing that hypercellularity by tumor cells reduced the extracellular space and mobility of water protons, resulting in increased signal intensity on diffusion-weighted images (3). Castillo et al (4) examined various vertebral metastases and found both low and high signal intensity in affected bone marrow on diffusion-weighted images with the same b-value, 165 seconds/mm 2 . They implied that in cases in which lesions are hypointense, the ADC remains normal despite tumor-related hypercellularity within a vertebra, leading to loss of signal on diffusion-weighted images.To our knowledge, Ward et al reported ADC of normal bone marrow for the first time, with a mean value of 0.15 ϫ 10 Ϫ3 mm 2 /second (5). Although it has been suggested that hypercellularity leads to a decrease or no change in ADC of bone marrow, this has not yet been verified. In this study, we sought to determine if there is a relation between ADC and cellularity of bone marrow, using in vivo data of various cellularity groups with histological confirmation. MATERIALS AND METHODS Patients and SubjectsThe study included four groups according to bone marrow cellularity: 1) adults with normal hypocellular marrow (21 patients, 15 men, 6 women; age range, 28 -86 years; mean age, 61.2 years); 2) adults with normal normocellular marrow (13 patients, 6 men, 7 women; age range, 43-78 years; mean age, 62.5 years); 3) young children with normal hypercellular marrow (5 patients, 3 boys, 2 girls; age range, 0 -3 years; mean age, 1.6 years); and 4) adults with lymphoma cell-pack...

Lanthionin‐Brücken sind wichtige Strukturelemente in natürlichen Lantibiotika, sie können aber auch in Peptide eingeführt werden, um deren biologische Aktivität und metabolische Stabilität zu erhöhen. Die Makrocyclisierung von Peptiden durch intramolekulare Cystein‐Thiolierung ist oft ein schwieriges Unterfangen, kann aber gelingen, wenn Cystein durch das reaktivere isostere Selenocystein ersetzt wird.

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A consensus-based guideline defining the clinical target volume primary was developed for external beam radiotherapy for intact uterine cervical cancer. This guideline will serve as a template for radiotherapy protocols in future clinical trials. It may also be used in actual clinical practice in the setting of highly precise external beam radiotherapy, including intensity-modulated radiotherapy.