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11.
Angiogenesis is a process that plays an important role in the growth and progression of cancer; growing evidence suggests that neovascularization is important in hematologic malignancies. Increased angiogenic potential has been identified in multiple myeloma (MM). In this study, investigators simultaneously measured the levels of hepatocyte growth factor (HGF), platelet-derived growth factor-AB (PDGF-AB), and transforming growth factor-alpha (TGF-/ga) through enzyme-linked immunosorbent assay in the bone marrow (BM) and peripheral blood (PB) of 30 patients with MM and 10 healthy controls. Differences in HGF values in BM sera were significant (P=.001) between patients and controls. In detailed analyses of HGF, PDGF-AB, and TGF-α, according to disease stage, a significant correlation was found between disease stage and BM HGF (P=.047), BM TGF-α (P=.021), and PB PDGF-AB (P=.006), respectively. When correlations between all other parameters were analyzed, significance was noted between PB TGF-α and lactate dehydrogenase (P=.02), PB TGF-α and PB HGF (P=.002), BM TGF-α and CD38 (P=.046), BM TGF-α and BM HGF (P=.000), BM TGF-α and BM PDGF-AB (P=.048), BM HGF and PB HGF (P=.044), and BM PDGF-AB and PB PDGF-AB (P=.000). BM HGF levels had a significant effect on overall survival, with disease severity assessed in terms of disease stage (P=.0018, log-rank test). These data show that in patients with MM, high levels of BM HGF, BM TGF-α, and PB PDGF-AB were associated with advanced disease stage; in addition, HGF played a significant role in disease processing and was related to disease severity. These findings have also led to the concept of a symbiotic relationship between the growth of myeloma cells and HGF, TGF-α, and PDGF-AB in BM.  相似文献   
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Turkish and Kurdish HLA profiles are studied for the first time. The comparative study of their allele frequencies, characteristic haplotypes, genetic distances with other Mediterraneans is complemented by neighbor-joining dendrograms and correspondence analyses. Turks, Kurds, Armenians, Iranians, Jews, Lebanese and other (Eastern and Western) Mediterranean groups seem to share a common ancestry: the older "Mediterranean" substratum. No sign of the postulated Indo-European (Aryan) invasion (1200 B.C.) is detected by our genetic analysis. It is concluded that this invasion, if occurred, had a relatively few invaders in comparison to the already settled populations, i.e. Anatolian Hittite and Hurrian groups (older than 2000 B.C.). These may have given rise to present-day Kurdish, Armenian and Turkish populations.  相似文献   
14.
Purpose

Hypophysitis is a heterogeneous condition that includes inflammation of the pituitary gland and infundibulum, and it can cause symptoms related to mass effects and hormonal deficiencies. We aimed to evaluate the potential role of machine learning methods in differentiating hypophysitis from non-functioning pituitary adenomas.

Methods

The radiomic parameters obtained from T1A-C images were used. Among the radiomic parameters, parameters capable of distinguishing between hypophysitis and non-functioning pituitary adenomas were selected. In order to avoid the effects of confounding factors and to improve the performance of the classifiers, parameters with high correlation with each other were eliminated. Machine learning algorithms were performed with the combination of gray-level run-length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray-level co-occurrence entropy.

Results

A total of 34 patients were included, 17 of whom had hypophysitis and 17 had non-functioning pituitary adenomas. Among the 38 radiomics parameters obtained from post-contrast T1-weighted images, 10 tissue features that could differentiate the lesions were selected. Machine learning algorithms were performed using three selected parameters; gray level run length matrix-low gray level run emphasis, gray-level co-occurrence matrix-correlation, and gray level co-occurrence entropy. Error matrices were calculated by using the machine learning algorithm and it was seen that support vector machines showed the best performance in distinguishing the two lesion types.

Conclusions

Our analysis reported that support vector machines showed the best performance in distinguishing hypophysitis from non-functioning pituitary adenomas, emphasizing the importance of machine learning in differentiating the two lesions.

  相似文献   
15.
第98届北美放射学年会(RSNA 2012)在美国芝加哥召开,该届大会共收录与前列腺相关的论文共58篇,以MRI为主,超声、PET等技术在前列腺中的的论文相对较少。这些论文主要关注于不同成像技术间的组合和优化在前列腺癌诊断与鉴别诊断中的应用价值。作者对以上方面的研究进展进行综述,旨在为我国前列腺影像学研究提供新的思路。  相似文献   
16.

Antiphospholipid syndrome (APS) is a systemic autoimmune disorder characterized by arterial and/ or venous thrombosis accompanied by persistently elevated levels of antiphospholipid antibodies (aPLs). The aim of this study is to evaluate the pulmonary manifestations of APS and compare the levels of aPLs in patients with and without pulmonary involvement. We retrospectively reviewed the files of patients with the diagnosis of APS between October 2010 and May 2017. Demographic data, clinical, radiological and laboratory findings were recorded. The study included 67 patients (56 female/11 male) with a mean age of 39?±?13 years. Pulmonary manifestations such as parenchymal and/or vascular involvement were seen in 12 (17.9%) patients. The patients with and without pulmonary manifestations were not significantly different in terms of age (p?=?0.46), comorbidities (p?=?0.48) and APS duration (p?=?0.66). Acute pulmonary thromboembolism (PE) was determined in 11 (16.4%), alveolar hemorrhage in 2 (3%) patients. Four patients with acute PE (36%) developed chronic thromboembolic pulmonary hypertension (CTEPH). One patient developed both CTEPH and diffuse alveolar hemorrhage after acute PE during follow up. Antiphosholipid antibody IgM was highly positive in patients with PE compared to patients without PE (p?=?0.005). Other antibodies and lupus anticoagulant were not significantly different in patients with and without PE. None of the patients were deceased due to pulmonary manifestations of APS. PE was the most common pulmonary manifestation of APS. The development of CTEPH was high among APS patients. Patients with APS should be closely followed for the onset of PE and CTEPH.

  相似文献   
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18.
The Human Leukocyte Antigen (HLA) typing of large groups of patients with various autoimmune diseases has demonstrated that some HLA alleles occur at higher frequencies in specific diseases than in the general population. Chronic urticaria has been shown to have an autoimmune basis by a previous study which found an association between chronic urticaria and specific HLA groups. We investigated the HLA subtypes of Turkish chronic urticaria patients. For this purpose 42 Turkish patients with chronic urticaria and 115 healthy controls were typed for HLA-DR and DQ by PCR-SSP (Polymerase Chain Reaction Sequence Specific Primers) low resolution DNA technique. We found an increased frequency of DR4 (42.9%, p=0.01) in chronic urticaria patients in comparison with that in healthy controls. This study supports the hypothesis that HLA alleles may be involved in the pathogenesis of chronic urticaria and that they appear to be directly involved in the initiation of the immune response.  相似文献   
19.
Primary hemangiopericytoma of the rib is extremely rare and only a few cases have been reported. A 62-yr-old man presented with an aching chest pain and dyspnea. Thoracic computed tomography revealed a homogenous mass expanding the right seventh rib. A diagnosis of hemangiopericytoma was established by percutaneous needle biopsy. Preoperative embolization of the feeding vessels of the tumor was performed in order to prevent perioperative bleeding. There was no significant bleeding during the surgery, where complete resection of the tumor with 7th to 9th ribs with a surgical margin of 5 cm was performed. Postoperative course was uneventful and there has been no recurrence for thirteen months. To our knowledge, there has been no report to apply a preoperative embolization of a primary hemangiopericytoma of the rib.  相似文献   
20.
Human kallikreins (hKs) have been reported to be involved in human cancers, and several hKs are promising biomarkers of various cancers, such as prostate, ovarian, breast, and testicular cancer. In the present study, we aimed to evaluate the prognostic value of immunohistochemical expression of hK11 in patients with gastric cancer. The study included 55 (36 men and 19 women; 58 ± 10 years of mean age) patients with gastric cancer treated with surgery and adjuvant chemoradiotherapy. Tissue sections were evaluated immunohistochemically with a monoclonal anti-hK11 antibody. Of the 55 patients, 35 (63.6%) were hK11-positive and 20 (36.4%) were hK11-negative. Disease-free and overall survival rates were significantly higher in patients with hK11 positive than in those with hK-11 negative expression (24 months vs. 11 months, p: 0.043; 29 months vs. 13 months, p: 0.038, respectively). In conclusion, hK11 expression in gastric cancer appears to be associated with a better prognosis. hK11 may be a prognostic biomarker of gastric cancer. On the other hand, it is needed to elucidate the mechanisms underlying the regulation of hK11 expression in gastric cancer.  相似文献   
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