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991.
Objective: Analysis of the results of 37 million cases by using cervical liquid-based cytology screening, discussion the situation of cervical cancer and precancerous lesions in Guangdong province. Methods: From 2002 to 2006, using liquid-based thin-layer cytology (TCT) method screening cervical lesions within 371,929 women in Guangdong. Cytological diagnosis adopt TBS (the Bethesda system) Standard (TBS improved 2001 version of the diagnostic criteria), statistic positive rate by age and region respectively. Results: 371,929 cases of gynecology cervical samples in Guangdong, 331,251 cases were negative, accounted for 91.23%; cytology positive cases: 32,548 cases were squamous intraepithelial lesions (8.96%), 486 cases were glandular epithelial lesions (0.13%); grouped according to age: 30 to 40-year-old positive rate was 9.13%, 40 to 50-year-old positive rate was 9.60%, the latter had higher cytology positive rate; grouped according to region: the total samples in PRD areas were 304.951 cases, accounted for 81.99%, in which 24301 cases were positive (8.14%), in 66978 cases (18.01%) of NON-PRD regions, 7645 cases were positive (11.87%), there were 1858 cases had biopsy/follow-up results from 2004 to 2005, and the rate was 2.88%. Conclusion: The cytological positive rate of cervical cancer and its precancerous lesions was 9.09% in Guangdong (of which the rate of cytological diagnosis as precancerous lesions was 3.40%), 30 to 50 age group had the high incidence of cervical cancer and its precursor lesions, and also the main stage of prevention for cervical cancer. Cytology positive rate was 11.87% in economic underdevelopment Non-Pearl River Delta regions, much higher than the Pearl River Delta region.  相似文献   
992.
Chan Su is a traditional Chinese medicine prepared from the dried white secretion of the auricular and skin glands of toads, and has been used as an oriental drug for the treatment of a number of diseases, including cancer. In this study, the potential of Chan Su (skin of Venenum Bufonis) to induce apoptosis in human lung carcinoma A549 cells was investigated. Treatment of A549 cells with skin of Venenum Bufonis resulted in the inhibition of cell growth and viability and the induction of apoptosis, which was shown by trypan blue counts, MTT assay, DAPI staining and flow cytometry analysis. The increase in apoptosis that was induced by skin of Venenum Bufonis was correlated with down-regulation of anti-apoptotic Bcl-2 expression, up-regulation of pro-apoptotic Fas ligand and death receptor 4, and a decrease in the mitochondrial membrane potential. Skin of Venenum Bufonis treatment induced the proteolytic activation of caspases and a concomitant degradation of poly(ADP-ribose)-polymerase and β-catenin protein. Cleavage of Bid and a down-regulation of the inhibitor of apoptosis family proteins were also observed in skin of Venenum Bufonis-treated A549 cells. Data from this study indicates that SVB induces the apoptosis of A549 cells through a signaling cascade of death receptor-mediated extrinsic and mitochondria-mediated intrinsic caspase pathways.  相似文献   
993.
苦瓜中新化合物的化学研究   总被引:4,自引:2,他引:2  
张瑜  崔炯谟  朴虎日  赵余庆 《中草药》2009,40(4):509-512
目的 研究苦瓜的新活性成分.方法 采用乙醇提取、微波萃取、D-101型大孔树脂纯化、硅胶柱色谱以及制备液相色谱等方法分离,通过理化常数及光谱数据鉴定化合物的结构.结果 分离并鉴定了8个化合物,分别为charantadiol A(5β,19-epoxycucurbita-6,23(E),25(26)-triene-3β,19(R)-diol,Ⅰ)、(+)-eduesmin(Ⅱ),blueme-nol A(Ⅲ)、宽叶葱苷元D(karatavilagenin D.Ⅳ)、5β,19-epoxycucurbita-6,23-diene-3β-19,23-triol(Ⅴ)、苦瓜皂苷元Ⅰ(5,19-epoxy-5β-cucurbita-6,23(E)-diene-3β,25-diol,Ⅵ)、苦瓜皂苷L昔元(aglycone of momordicoside L,3β,7β,25-trihydroxy-cucurbita-5,23(E)-diene-19-al,Ⅶ)、β-谷甾醇(β-sitosterol,Ⅷ ).结论 化合物Ⅰ为新化合物,命名为苦瓜二醇A(charantadiol A),化合物Ⅱ、Ⅲ为从苦瓜中首次分离得到.  相似文献   
994.
995.
996.
The sensitivity and specificity of endoscopic ultrasound (EUS) for esophageal cancer are variable. The aim of the present study was to determine the accuracy of EUS for the T staging of esophageal cancer and to explore the factors that affect the accuracy.This was a retrospective study of patients with esophageal cancer who underwent EUS between January 2018 and September 2019 at the author''s hospital. All patients underwent EUS, surgery, and pathological examination. The diagnostic value of ultrasound-based T (uT) staging was evaluated using the pathological T (pT) staging as the gold standard.Finally, 169 patients were included. Among the 169 patients, 37 were overstaged by EUS, 33 were understaged, and 99 were correctly staged. The overall accuracy of EUS was 58.6%. Sensitivity was low, at 0% to 70.8% depending upon the pT stage, but specificity was higher, at 71.0% to 100.0%, also depending upon the pT stage. The multivariable analysis revealed that highly differentiated tumors (odds ratio = 9.167, P = .041) and pT stage ≥T2 (odds ratio = 2.932, P = .004) were independent factors of accurate uT stage.The staging of esophageal cancer using EUS has low sensitivity but high specificity. Highly differentiated tumors and pT stage ≥2 tumors were associated with the accuracy of uT staging.  相似文献   
997.
Aim: Abnormal ankle-brachial index (ABI) is regarded as peripheral artery disease and can be used to predict cardiovascular (CV) outcomes. However, the usefulness of ABI for the prediction of CV outcome in patients with normal ABI is limited. Upstroke time per cardiac cycle (UTCC) is recently reported to be associated with mortality in patients with acute myocardial infarction and the elderly. Therefore, we aimed to evaluate UTCC, left ventricular ejection fraction (LVEF), brachial-ankle pulse wave velocity (baPWV), and ABI for the prediction of mortality in patients with normal ABI. Methods: Patients arranged for echocardiographic examinations were enrolled, and 1076 patients with normal ABI were included. ABI, baPWV, and UTCC were measured by an ABI-form device. Results: The median follow-up to mortality was 95 months. There were 88 CV and 244 all-cause deaths. After multivariate analysis, UTCC was associated with increased CV and all-cause mortality ( P ≤ 0.004). Age, diabetes, heart failure, left ventricular hypertrophy, baPWV, and LVEF were also independent predictors of CV and all-cause mortality, but ABI was not. Furthermore, UTCC had a better additive predictive value than ABI, baPWV, and LVEF for CV mortality ( P ≤ 0.012). It also had a better additive predictive value than ABI and LVEF for all-cause mortality ( P ≤ 0.013). Conclusions: UTCC is an independent predictor for CV and all-cause mortality in patients with normal ABI. It also has a better additive predictive value of CV and all-cause mortality than ABI and LVEF. Therefore, UTCC is a simple, novel, and useful parameter for identifying high-risk patients with normal ABI.  相似文献   
998.
Hepatocellular carcinoma (HCC) is among the most common and lethal human cancers worldwide and is closely associated with chronic hepatitis B virus (HBV) infection. Pre-S deleted proteins are naturally occurring mutant forms of HBV large surface proteins that are expressed by HBV surface genes harboring deletion mutations over the pre-S gene segments. It has been well demonstrated that HBV pre-S deleted proteins function as important oncoproteins, which promote malignant phenotypes of hepatocytes through the activation of multiple oncogenic signaling pathways and result in HCC formation. The oncogenic signaling pathways activated by pre-S deleted proteins have been verified as potential therapeutic targets for the prevention of HCC development. Moreover, the presence of pre-S gene deletions and the expression of pre-S deleted proteins in the blood and liver tissues of HBV-infected patients have been evaluated as valuable biomarkers for predicting a higher risk of HCC development and recurrence after curative surgical resection. Therefore, the precise detection of pre-S gene deletions and pre-S deleted proteins holds great promise as regards identifying the patients at higher risk of HCC development and recurrence, thus aiding in more timely and better treatments to improve their survival. This review summarizes the major approaches used for the detection of pre-S gene deletions and pre-S deleted proteins, including the approaches based on Sanger DNA sequencing, pre-S gene chips, next-generation sequencing and immunohistochemistry staining, and it highlights their important applications in the prediction of higher risks of HCC development and recurrence.  相似文献   
999.
This study compared the immunogenicity of inactivated SARS-CoV-2 vaccines between people living with HIV (PLWH) and HIV-negative individuals. We recruited 120 PLWH and 53 HIV-negative individuals aged 18–59 years who had received an inactivated SARS-CoV-2 vaccine in two Chinese cities between April and June 2021. Blood samples were tested for immunogenicity of the inactivated SARS-CoV-2 vaccines. The prevalence and severity of adverse events associated with SARS-CoV-2 vaccines were similar between PLWH and HIV-negative individuals. The seropositivity of neutralizing activity against authentic SARS-CoV-2, of the total amount of antibody (total antibody) and of S-IgG were 71.3%, 81.9%, and 92.6%, respectively, among fully vaccinated PLWH. Among all participants, PLWH had lower neutralizing activity, total antibody, S-IgG, and T-cell-specific immune response levels, compared to HIV-negative individuals, after controlling for types of vaccine, time interval between first and second dose, time after receiving the second dose, and sociodemographic factors. PLWH with a longer interval since HIV diagnosis, who received their second dose 15–28 days prior to study commencement, and who had an interval of ≥21 days between first and second dose had higher neutralizing activity levels. The immunogenicity of the inactivated SARS-CoV-2 vaccines was lower among PLWH as compared to HIV-negative individuals. Vaccination guideline specific for PLWH should be developed.  相似文献   
1000.
BackgroundIn diabetic retinopathy (DR) screening programmes feature-based grading guidelines are used by human graders. However, recent deep learning approaches have focused on end to end learning, based on labelled data at the whole image level. Most predictions from such software offer a direct grading output without information about the retinal features responsible for the grade. In this work, we demonstrate a feature based retinal image analysis system, which aims to support flexible grading and monitor progression.MethodsThe system was evaluated against images that had been graded according to two different grading systems; The International Clinical Diabetic Retinopathy and Diabetic Macular Oedema Severity Scale and the UK’s National Screening Committee guidelines.ResultsExternal evaluation on large datasets collected from three nations (Kenya, Saudi Arabia and China) was carried out. On a DR referable level, sensitivity did not vary significantly between different DR grading schemes (91.2–94.2.0%) and there were excellent specificity values above 93% in all image sets. More importantly, no cases of severe non-proliferative DR, proliferative DR or DMO were missed.ConclusionsWe demonstrate the potential of an AI feature-based DR grading system that is not constrained to any specific grading scheme.Subject terms: Diagnosis, Medical imaging  相似文献   
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