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91.
目的采用排列熵和R峰检测相结合方法,定位室性心律失常的发生时间。方法首先检测出心电信号,利用检测出的R峰作为辅助,近似地划分每个心律节拍;然后利用移动窗口对心电信号进行排列熵计算,从排列熵的变化可以精确地反映出心电信号的规则性的变化;最后综合RR间期和排列熵的变化检测室性心律失常的节拍。结果利用MIT-BIH心律失常和恶性室性心律失常数据库对该算法进行检测,正确率达到97%。结论该方法能够快速精确地检测出室性心律失常。 相似文献
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The present study was aimed at evaluating clinicopathologic and immunohistochemical (IHC) features of 300 rhabdomyosarcomas (RMSs), including differential IHC expression and prognostic value of myogenin and MyoD1 across various subtypes of RMSs.IHC expression of myogenin and MyoD1 was graded on the basis of percentage of tumor cells displaying positive intranuclear immunostaining i.e. grade 1 (1–25%); grade 2 (26–50%); grade 3 (51–76%) and grade 4 (76–100%).Clinical follow-up was available in 238 (79.3%) patients. Various clinicopathologic parameters were correlated with 3-year disease free survival (DFS) and overall survival (OS).There were 140 cases (46.7%) of alveolar RMS (ARMS), 90 of embryonal RMS (ERMS) (30%), 61 (20.3%) of spindle cell/sclerosing RMS and 9 cases (3%) of pleomorphic RMS. Most cases, barring pleomorphic RMSs, occurred in the first two decades (228 cases) (76%), frequently in males, in the head and neck region (126) (42%).By immunohistochemistry, desmin was positive in 292/299 (97.6%) tumors; myogenin in 238/267 (89.1%) and MyoD1 in 192/266 (72.2%) tumors. High myogenin expression (in ≥51% positive tumor cells) was significantly associated with ARMSs (95/121, 78.5%), as compared to other subtypes (48/117, 41%) (p value < 0.001). High MyoD1 expression (≥51% tumor cells) was seen in more cases of pure sclerosing, combined with spindle cell/sclerosing RMSs (10/10, 100%), as compared to the other subtypes (91/141, 67.4%) (p = 0.032).There was no significant difference between high myogenin expression and clinical outcomes. Patients without metastasis and harbouring tumors, measuring ≤5 cm showed a significant increase in OS, with p values = 0.01 and <0.001, respectively.ARMS was the most frequent subtype. There was a significant association between high myogenin expression and ARMSs and high MyoD1 expression and spindle cell/sclerosing RMSs. High myogenin expression did not correlate with clinical outcomes. Patients with smaller sized tumors and without metastasis had significantly better clinical outcomes. 相似文献
96.
Hongyu Shen Liangpeng Li Siying Zhou Dandan Yu Sujin Yang Xiu Chen Dandan Wang Shanliang Zhong Jianhua Zhao Jinhai Tang 《Tumour biology》2016,37(12):15359-15370
A disintegrin and metalloproteinase (ADAM) family members are known to process the target membrane-bound molecules through the quick induction of their protease activities under interaction with other molecules, which have diverse roles in tissue morphogenesis and pathophysiological remodeling. Among these, ADAM17 is a membrane-bound protease that sheds the extracellular domain of various receptors or its ligands from the cell membrane and subsequently activates downstream signaling transduction pathways. Importantly, breast cancer remains a mainspring of cancer-induced death in women, and numerous regulatory pathways have been implicated in the formation of breast cancer. Substantial evidence has demonstrated that an obvious increased in ADAM17 cell surface expression has been discovered in breast cancer and was shown to be associated with mammary tumorigenesis, invasiveness, and drug resistance. Over the last decades, it has received more than its share of attention that ADAM17 plays a potential role in breast cancer, including cell proliferation, invasion, angiogenesis, apoptosis, and trastuzumab resistance. In our review, we discuss the mechanisms through which ADAM17 acts on breast cancer tumorigenesis and progression. Thus, this will provide further impetus for exploiting ADAM17 as a new target for breast cancer treatment. 相似文献
97.
The possible origin of proliferative inflammatory atrophy in the regenerative proliferation of prostate epithelial cells in response to injury caused by inflammation, and their relation to prostate adenocarcinoma have not been defined. Inflammation and focal atrophy are common pathological findings in prostate biopsies, currently not routinely included in surgical pathology reports. The objective of the study was to determine the correlation between inflammation and focal atrophy with prostate adenocarcinoma. Prostate needle biopsies from 203 patients with clinical parameters suspicious for malignancy were evaluated for the presence and extent of chronic inflammation, type and grade of focal atrophy, high-grade intraepithelial neoplasia, and adenocarcinoma. Relations among them and with age were also analyzed. χ2 tests and binary logistic regression were used to estimate associations. Chronic inflammation was observed in 77.3% of the biopsies, significantly associated to adenocarcinoma (P = .031). Moderate/severe inflammation in at least 1 biopsy core increased the risk of prostate adenocarcinoma (odds ratio, 2.94; 95% confidence interval, 1.27-6.8), whereas glandular localization of inflammation decreased the risk. Focal atrophy was present in 72.9% of the biopsies, proliferative inflammatory atrophy was the most common type, and its grade was significantly associated to inflammation (P < .0001) and inflammation intensity (P = .003). An association between prostate adenocarcinoma and inflammation was found, with higher odds in presence of moderate/severe inflammation in at least 1 biopsy core. Increasing grades of proliferative inflammatory atrophy were associated to high levels of inflammation, supporting its previously proposed inflammatory nature. 相似文献
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《Current problems in cancer》2021,45(5):100712
To assess the clinicopathological features, prognostic factors, and survival rates associated with uterine leiomyosarcoma (uLMS). Databases from 15 participating gynecological oncology centers in Turkey were searched retrospectively for women who had been treated for stage I-IV uLMS between 1996 and 2018. Of 302 consecutive women with uLMS, there were 234 patients with Federation of Gynecology and Obstetrics (FIGO) stage I disease and 68 with FIGO stage II-IV disease. All patients underwent total hysterectomy. Lymphadenectomy was performed in 161 (54.5%) cases. A total of 195 patients received adjuvant treatment. The 5-year disease-free survival (DFS) and overall survival (OS) rates were 42% and 54%, respectively. Presence of lymphovascular space invasion (LVSI), higher degree of nuclear atypia, and absence of lymphadenectomy were negatively correlated with DFS, while LVSI, mitotic count, higher degree of nuclear atypia, FIGO stage II-IV disease, and suboptimal surgery significantly decreased OS. LVSI and higher degree of nuclear atypia appear to be prognostic indicators for uLMS. Lymphadenectomy seems to have a significant effect on DFS but not on OS. 相似文献
100.
Chronic aflatoxin exposure has long been related to hepatocellular carcinoma (HCC). Recently, its association with gallbladder cancer (GBC) was postulated. Here we present the data supporting this hypothesis in Chile, the country with the highest GBC mortality worldwide with age-standardized mortality rates (ASMR) of 10.3 in women and 5.04 in men.The highest GBC rates occur in Southern Chile (ASMR = 18), characterized by: high Amerindian ancestry, associated with high bile acid synthesis and gallstones; high poverty and high cereal agriculture, both associated with aflatoxin exposure. Aflatoxins have been detected in imported and locally grown foods items. We estimated population dietary exposure ranging from 0.25 to 35.0 ng/kg-body weight/day. The only report on human exposure in Chile found significantly more aflatoxin biomarkers in GBC than in controls (Odds Ratio = 13.0).The hypothesis of aflatoxin-GBC causal link in the Chilean population is supported by: genetically-determined rapid cholesterol excretion and high gallstones prevalence (49.4%); low prevalence of HCC (ASMR = 4.9) and low HBV infection (0.15%) the main co-factor of aflatoxins in HCC risk.If the association between aflatoxins and GBC were confirmed, public health interventions based on food regulation could have a substantial public health impact. 相似文献