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991.
We report the characterization of a de novo unbalanced chromosome rearrangement by comparative genomic hybridization (CGH) in a 15-day-old child with hypotonia and dysmorphia. We describe the combined use of CGH and fluorescence in situ hybridization (FISH) to identify the origin of the additional chromosomal material on the short arm of chromosome 6. Investigation with FISH revealed that the excess material was not derived from chromosome 6. Identification of unknown unbalanced aberrations that could not be identified by traditional cytogenetics procedures is possible by CGH analysis. Visual analysis of digital images from CGH-metaphase spreads revealed a predominantly green signal on the telomeric region of chromosome 10p. After quantitative digital ratio imaging of 10 CGH-metaphase spreads, a region of gain was found in the chromosome band 10p14-pter. The CGH finding was confirmed by FISH analysis, using a whole chromosome 10 paint probe. These results show the usefulness of CGH for a rapid characterization of de novo unbalanced translocation, unidentifiable by karyotype alone.  相似文献   
992.
In 20 patients with congenital and acquired lymphedema in either upper or lower extremities and in four patients without extremity edema, human serum albumin labeled with technetium-99m was injected intradermally into a digital web space of the hand or foot. With a digital gamma camera that permitted a "sweep" of the torso, serial extremity and whole-body lymphagioscintigraphy (LAS) of the peripheral lymphatic system was performed. In 11 patients with acquired lymphedema, a well-defined obstructive pattern was seen, characterized by discrete peripheral lymphatic trunks, delayed or absent depiction of regional nodes, and delayed but extensive soft-tissue tracer extravasation. Five of nine patients with congenital lymphedema showed hypoplasia characterized by poorly defined lymphatic trunks, delayed depiction of regional nodes, and early and extensive extravasation of tracer. The other four patients showed aplasia, with absence of trunks, no depiction of nodes, and little or no tracer extravasation. LAS is technically simple to perform and requires no special training. Radiation exposure is minuscule, and the procedure is safe and without apparent side effects. For these reasons, whole-body LAS should be the preferred method for the initial assessment of congenital or acquired lymphedema.  相似文献   
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Background:This article presents the design of PROFILe, a study investigating which (bio)medical and non-(bio)medical patient characteristics should guide more tailored chronic care. Based on this insight, the project aims to develop and validate ‘patient profiles’ that can be used in practice to determine optimal treatment strategies for subgroups of chronically ill with similar healthcare needs and preferences.Methods/Design:PROFILe is a practice-based research comprising four phases. The project focuses on patients with type 2 diabetes. During the first study phase, patient profiles are drafted based on a systematic literature research, latent class growth modeling, and expert collaboration. In phase 2, the profiles are validated from a clinical, patient-related and statistical perspective. Phase 3 involves a discrete choice experiment to gain insight into the patient preferences that exist per profile. In phase 4, the results from all analyses are integrated and recommendations formulated on which patient characteristics should guide tailored chronic care.Discussion:PROFILe is an innovative study which uses a uniquely holistic approach to assess the healthcare needs and preferences of chronically ill. The patient profiles resulting from this project must be tested in practice to investigate the effects of tailored management on patient experience, population health and costs.  相似文献   
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One of the challenges of tailored antiangiogenic therapy is the ability to adequately monitor the angiogenic activity of a malignancy in response to treatment. The αvβ3 integrin, highly overexpressed on newly formed tumor vessels, has been successfully used as a target for Arg-Gly-Asp (RGD)-functionalized nanoparticle contrast agents. In the present study, an RGD-functionalized nanocarrier was used to image ongoing angiogenesis in two different xenograft tumor models with varying intensities of angiogenesis (LS174T > EW7). To that end, iron oxide nanocrystals were included in the core of the nanoparticles to provide contrast for T2*-weighted magnetic resonance imaging (MRI), whereas the fluorophore Cy7 was attached to the surface to enable near-infrared fluorescence (NIRF) imaging. The mouse tumor models were used to test the potential of the nanoparticle probe in combination with dual modality imaging for in vivo detection of tumor angiogenesis. Pre-contrast and post-contrast images (4 hours) were acquired at a 9.4-T MRI system and revealed significant differences in the nanoparticle accumulation patterns between the two tumor models. In the case of the highly vascularized LS174T tumors, the accumulation was more confined to the periphery of the tumors, where angiogenesis is predominantly occurring. NIRF imaging revealed significant differences in accumulation kinetics between the models. In conclusion, this technology can serve as an in vivo biomarker for antiangiogenesis treatment and angiogenesis phenotyping.  相似文献   
999.

Background  

Women with Down syndrome very rarely develop breast cancer even though they now live to an age when it normally occurs. This may be related to the fact that Down syndrome persons have an additional copy of chromosome 21 where the gene that codes for the antiangiogenic protein Endostatin is located. Can this information lead to a primary antiangiogenic therapy for early stage breast cancer that indefinitely prolongs remission? A key question that arises is when is the initial angiogenic switch thrown in micrometastases? We have conjectured that avascular micrometastases are dormant and relatively stable if undisturbed but that for some patients angiogenesis is precipitated by surgery. We also proposed that angiogenesis of micrometastases very rarely occurs before surgical removal of the primary tumor. If that is so, it seems possible that we could suggest a primary antiangiogenic therapy but the problem then arises that starting a therapy before surgery would interfere with wound healing.  相似文献   
1000.
In order to clarify which teaching form encourages student' s self-motivation learning ability better, we did a comparison experiment between problem-based learning (PBL)and lecture-based learning (LBL) in a 3rd year course in basic pharmacology. Of 224 students who participated (124 PBL, 100 LBL) in pharmacology course, the experimental group was divided into 6 teams(20 - 21 students for each team with one tutor)using PBL method with 7 clinical cases discussion while o.ther 100 students held in the same lecture-based format as the traditional LBL course as a control group. In 224 students, 50.4% using PBL method self-directed learning ability had increased compared with 35.3% in LBL teaching mode. The test score indicated that students using LBL teaching method scored overall higher than those using PBL mode, especially at objective items, this result was significant.. iy different(P =0.009). However, as far as subjective items are concerned, students accepted PBL mode showed their superior advantages over the LBL ones. Similarly, the result was significantly different( P =0.001 ). On the whole, PBL method supported by appropriate technology and teachers, has allowed our students to analyze authentic situations as a doctor status and the active learning ability by self-motivation study will be undoubtedly beneficial for their becoming life-long learners and excellent doctors in the future.  相似文献   
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