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目的评价乳腺癌传统适形放疗和调强放疗靶区剂量分布和心、肺组织接受的剂量。方法使用Eclipse三维治疗计划系统,对37例乳腺癌术后分别实施传统适形放射治疗和调强放射治疗计划。比较两种放射治疗计划的剂量分布和心、肺组织的受量。结果处方剂量为5000cGy时,调强放疗的靶区剂量分布更理想,且心、肺组织受照射剂量和体积也明显少于适形放射治疗。  相似文献   
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This study was aimed at evaluating the performance of the innovative technique Smart Fetus (SF) developed to recognize the planes and obtain the basic biometric measurements of fetuses automatically. This prospective study included 1005 uncomplicated singleton pregnancies undergoing routine examinations. For every pregnancy, planes, including the transverse section of the thalami, transverse section of the abdomen and longitudinal section of the femur, were acquired, and standard biometric measurements, including biparietal diameter, head circumference, abdominal circumference and femur length, were obtained using SF and traditional ultrasound technique (TUT). The accuracy, reproducibility and time required for the analysis of SF were compared with those of TUT. In 998 of 1005 cases (99.30%), SF successfully acquired the sections and made all measurements. The agreement between the techniques was high for all measurements. The time to obtain sections and measure biometric parameters or solely measure biometric parameters was significantly shorter with SF than with TUT. No significant differences were found in SF repeated measurements obtained by two independent observers. The SF technique helped in the acquisition of reliable standard sections and biometric measurements and saved time. It might serve as a novel ultrasound scanning approach and improve workflow efficiency.  相似文献   
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Notch signaling plays an essential role in development as well as cancer. We have previously shown that Notch3 is important for lung cancer growth and survival. Notch receptors are activated through the interaction with their ligands, resulting in proteolytic cleavage of the receptors. This interaction is modulated by Fringe, a family of fucose-specific β1,3 N-acetylglucosaminyltransferases that modify the extracellular subunit of Notch receptors. Studies in developmental models showed that Fringe enhances Notch’s response to Delta ligands at the expense of Jagged ligands. We observed that Manic Fringe expression is down-regulated in lung cancer. Since Jagged1, a known ligand for Notch3, is often over-expressed in lung cancer, we hypothesized that Fringe negatively regulates Notch3 activation. In this study, we show that re-expression of Manic Fringe down-regulates Notch3 target genes HES1 and HeyL and reduces tumor phenotype in vitro and in vivo. The mechanism for this phenomenon appears to be related to modulation of Notch3 protein stability. Proteasome inhibition reverses Manic Fringe-induced protein turnover. Taken together, our data provide the first evidence that Manic Fringe functions as a tumor suppressor in the lung and that the mechanism of its anti-tumor activity is mediated by inhibition of Notch3 activation.  相似文献   
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This study was the first to detect the presence of the two compounds momilactone A (MA) and momilactone B (MB) in rice bran using liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). By in vitro assays, both MA and MB exhibited potent inhibitory activities on pancreatic α-amylase and α-glucosidase which were significantly higher than γ-oryzanol, a well-known diabetes inhibitor. Remarkably, MA and MB indicated an effective inhibition on trypsin with the IC50 values of 921.55 and 884.03 µg/mL, respectively. By high-performance liquid chromatography (HPLC), quantities of MA (6.65 µg/g dry weight) and MB (6.24 µg/g dry weight) in rice bran were determined. Findings of this study revealed the α-amylase, α-glucosidase and trypsin inhibitors MA and MB contributed an active role to the diabetes inhibitory potential of rice bran.  相似文献   
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Background contextVertebral hemangiomas (VHs) are called benign tumors but are actually just vascular malformations. The diagnosis and treatment for aggressive VHs is still controversial, due to their rarity.PurposeTo evaluate the safety and efficiency of the present diagnostic methods and treatment choices.Study designA retrospective study of aggressive VHs with neurologic deficit.Patients sampleA total of 29 consecutive aggressive VH cases were diagnosed and treated in our department since 2001.Outcome measuresWe routinely took anteroposterior and lateral spinal roentgenograms, computed tomography, and magnetic resonance images.MethodsTrocar biopsy is indicated in suspected malignant cases. Radiotherapy was usually our first choice if the neurologic deficit was mild or developed slowly. Surgery was indicated if the neurologic deficit was severe or developed quickly or if the radiotherapy was not effective.ResultsThis series included 12 males and 17 females, and the mean age at diagnosis was 44.0 years (range, 21–72 years). Ten patients had radiculopathy, 1 had cauda equina syndrome, and 18 cases had myelopathy. Twenty-one cases had lesions in the thoracic spine, 5 in the lumbar, and 3 in the cervical region. Eleven cases had untypical image findings, including five cases with pathologic vertebral fracture. The neurologic compression came from only epidural soft tumor mass in 18 cases, whereas it came from both bony compression and soft lesion in the other 11 cases. Ten cases had radiotherapy alone, but two failed and had surgery later. Twenty-one cases had surgery. In the 12 cases having surgical decompression without vertebroplasty, the average estimated blood loss was 1900 mL, and it was 1093 mL for the eight cases having decompression with vertebroplasty. The average follow-up was 51.1 months (range, 24–133 months). There was no recurrence in those cases with radiotherapy, whereas three had local recurrence in those six cases treated by surgical decompression alone without radiotherapy.ConclusionsIn aggressive VHs, epidural soft-tissue compression was usually the main reason for neurologic deficit. In cases with rapid progressive and/or severe myelopathy, posterior decompression and stabilization could be combined with intraoperative vertebroplasty to reduce blood loss.  相似文献   
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