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排序方式: 共有7172条查询结果,搜索用时 15 毫秒
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Laleh Ehsani Rishie Seth Stephanie Bacopulos Arun Seth Adeboye O. Osunkoya 《Tumour biology》2013,34(2):787-791
The distinction between renal oncocytoma and renal cell carcinoma, especially chromophobe renal cell carcinoma and clear cell carcinoma with oncocytic features, is important due to the different biologic potentials of these tumors. RING E3 ligases have the subject of intense studies for their roles in many diseases including cancer and as potential therapeutic targets. All RING E3 ligases, including BCA2, contain a consensus protein sequence that would complex two or more zinc ions in the expressed protein. Identification of which ubiquitin ligases specifically affect distinct cellular processes is essential to the development of targeted therapeutics in these tumors. The ubiquitin–proteasome system regulates the turnover of proteins that have essential roles in the cell cycle, apoptosis, DNA damage repair, and in protein trafficking, which makes this pathway a target for oncogenic events. In this study, we investigated expression of BCA2 in renal oncocytoma and renal cell carcinoma. A total of 158 patients were included in the study. Our study has shown that 114/114 (100 %) cases of renal cell carcinoma were negative for BCA2. All 38 (100 %) cases of renal oncocytoma were positive for BCA2, and 6/6 (100 %) cases designated as oncocytic neoplasm which favor oncocytoma were also positive for BCA2. This is the first study to date evaluating the expression of BCA2 in renal oncocytoma. BCA2 could serve as a marker that may be utilized in the distinction between renal oncocytoma and its mimickers. 相似文献
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Parker E.Ludwig Finosh G.Thankam Arun A.Patil Andrea J.Chamczuk Devendra K.Agrawal 《中国神经再生研究》2018,(1)
Many therapies with potential for treatment of brain injury have been investigated. Few types of cells have spurred as much interest and excitement as stem cells over the past few decades. The multipotentiality and self-renewing characteristics of stem cells confer upon them the capability to regenerate lost tissue in ischemic or degenerative conditions as well as trauma. While stem cells have not yet proven to be clinically effective in many such conditions as was once hoped, they have demonstrated some effects that could be manipulated for clinical benefit. The various types of stem cells have similar characteristics, and largely differ in terms of origin; those that have differentiated to some extent may exhibit limited capability in differentiation potential. Stem cells can aid in decreasing lesion size and improving function following brain injury. 相似文献
96.
Arun A. Mavanur Vamsi Parimi Mark O’Malley Marina Nikiforova David L. Bartlett Jon M. Davison 《International journal of experimental pathology》2010,91(4):357-367
We describe the clinical, pathologic and molecular characteristics of a xenograft model of metastatic mucinous appendiceal adenocarcinoma. Tumours from patients with mucinous appendiceal neoplasms were implanted in nude mice and observed for evidence of intraperitoneal tumour growth. Morphologic and immunohistochemical features, temporal growth characteristics relative to controls, and loss of heterozygosity (LOH) at multiple chromosomal alleles were assessed in a successfully engrafted tumour. Two of seventeen implanted tumours successfully engrafted and only one mucinous adenocarcinoma propagated throughout the course of the study. The successful xenograft is morphologically similar to the original tumour, produces abundant extracellular mucin and exhibits non‐invasive growth on peritoneal surfaces. The temporal growth characteristics of the xenograft tumour relative to controls reveal that tumour burden can be followed indirectly by measuring the weight or abdominal girth of engrafted animals. The cytokeratin, mucin core protein, CDX2, Ki‐67 and p53 expression patterns are identical in the xenograft and resected tumour and are consistent with the expected pattern of protein expression for mucinous adenocarcinoma of the appendix. LOH was found in 1 of 10 informative chromosomal loci (chromosome 10p23) in xenograft tumour cells. Although we were unable to engraft a low‐grade appendiceal mucinous neoplasm, the engrafted adenocarcinoma will be useful for future evaluation of novel therapeutic strategies directed at mucinous appendiceal adenocarcinoma and evaluation of strategies for treating widespread, bulky, mucinous peritoneal surface neoplasms. Xenograft tumour enrichment can facilitate molecular studies of appendiceal epithelial neoplasia. 相似文献
97.
The relevance of breastfeeding and complementary feeding as proven child survival interventions, is well documented by the
scientific research. These two preventive interventions can save as many as 19% of all child deaths. However, despite the
volume of evidence favouring mainstreaming of these interventions, many countries, including India are yet to achieve universal
appropriate infant and young child feeding practices. This article attempts to explore the evidenced based role of these interventions
in the crusade to save children, and looks into the present scenario of infant and young child feeding in India, along with
a possible road map to achieve high rates of early and exclusive breastfeeding and appropriate complementary feeding in the
country. 相似文献
98.
Fatigue is a common symptom of advanced cancer limiting one''s activity and affecting the quality of life. It is a multidimensional symptom complex with subjective and objective components. Hence, its definition and assessment seems arbitrary, incomplete, and elusive. Components of fatigue often merge with other ‘disease states’ as anemia, depression and so on, compounding difficulty to assess it separately. Fatigue has a high prevalence rate, and lasts longer in chronic diseases like cancer. Its association with treatment modalities like chemotherapy, radiotherapy alongside the primary disease process makes it seemingly ubiquitous in many cases. Systemic manifestation of cancer causes excess demand on body resources on cell repair, uncontrolled growth with metabolite accumulation causing fatigue. Co-morbid conditions of organic and psychological nature causes fatigue. There are many assessment tools for fatigue with different uses and objectives, simple and reproducible tools like Brief Fatigue Inventory, Edmonton Symptom assessment scale seem feasible in everyday practice. Management of fatigue is not straightforward and rewarding. Although treatment of cause appears to be an attractive option, it is not possible in all cases. Therapeutic agents targeting cytokine load is in early stages of study and available results are not favorable. Specific measures aimed at pain relief, prevention/treatment of sepsis, management of depression, avoidance of drugs causing fatigue, restoring the metabolic profile are important. Methyl phenidate, megestrol, and modafinil are some drugs with promising effect to treat fatigue, though confirmatory studies are yet to be established. Non-pharmacological methods are also helpful. Forewarning patients on upcoming fatigue, active regular exercise, and stress management are some of them. Fatigue being a multidimensional entity, single mode of therapy is insufficient. Combined modality tailored to individual patient need and understanding may be the right way to battle this ill-understood symptom. This review article examines the etiopathogenesis and management strategies of fatigue in cancer. 相似文献
99.
Clinical and histologic spectrum of nonalcoholic fatty liver disease associated with normal ALT values 总被引:34,自引:0,他引:34
Mofrad P Contos MJ Haque M Sargeant C Fisher RA Luketic VA Sterling RK Shiffman ML Stravitz RT Sanyal AJ 《Hepatology (Baltimore, Md.)》2003,37(6):1286-1292
A retrospective study was performed to (1) characterize the clinical and histologic features of those with nonalcoholic fatty liver disease (NAFLD) and normal alanine aminotransferase (ALT) values, (2) compare the spectrum of NAFLD associated with normal versus elevated ALT levels, and (3) determine whether there were differences in the clinical or histologic spectrum of NAFLD between those with a low normal versus high normal ALT value. A total of 51 subjects with NAFLD and normal ALT were identified and compared with 50 consecutive subjects with NAFLD and elevated ALT. The major indications for liver biopsy in those with normal ALT were unexplained hepatomegaly (n = 21) and evaluation as a potential donor for living donor liver transplantation (n = 16). The 2 groups were comparable with respect to age, gender distribution, and ethnicity. Approximately 80% of cases in both groups had at least 1 feature of the metabolic syndrome, the major risk factor for NAFLD. The 2 groups were also comparable with respect to the grade of the individual histologic parameters of NAFLD. A total of 12 subjects with normal ALT levels had bridging fibrosis, whereas 6 had cirrhosis. Diabetes was the only factor independently associated with an increased risk of advanced fibrosis (bridging fibrosis or cirrhosis) by multivariate analysis (relative risk: 2.3, P <.01). The mean steatosis (1.6 vs. 2.16, P <.04) and perisinusoidal fibrosis scores (0.35 vs. 0.9, P <.049) were lower in those with low normal (<30 IU/L) ALT versus high normal ALT. However, the prevalence of advanced fibrosis was similar (5 of 15 vs. 13 of 36, respectively). In conclusion, (1) the entire histologic spectrum of NAFLD can be seen in individuals with normal ALT values, (2) the histologic spectrum in these individuals is not significantly different from those with elevated ALT levels, and (3) a low normal ALT value does not guarantee freedom from underlying steatohepatitis with advanced fibrosis. 相似文献