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161.
目的分析厦门市3-6岁儿童龋病发生的相关因素并进行危险性评估,为全面制定儿童龋病预防的综合措施,尤其是为高危患龋儿童的口腔健康保健提供依据。方法采取多阶段、分层、整群抽样的方法,对厦门市幼儿园3-6岁儿童进行患龋情况调查,并通过发放问卷,对患儿的生长发育、饮食习惯、口腔行为、家庭情况、生活环境、干预措施等6个方面的16个变量进行χ^2检验及Logisticforward回归分析,建立回归模型。结果厦门市3-6岁儿童的乳牙患龋率为71.77%,龋均为4.70,龋面均为7.43。月龄、进食碳酸饮料频率、睡前进食、进食奶制品频率、开始刷牙年龄、家长受教育程度、托幼机构、居住地、家长的口腔保健知识、局部用氟、子女数目、进食甜食频率等与儿童龋病的发生具有相关性,性别、每天刷牙次数、牙膏种类和家庭收入与儿童龋病的发生无相关性。建立的儿童龋病回归模型可在一定程度上对患龋危险性进行预测。结论对儿童龋病应综合防治,从小培养儿童健康的饮食习惯,加强对家长的口腔健康知识教育,并合理局部用氟。  相似文献   
162.
163.
In order to find an appropriate model suitable for a multistate survival experiment, 634 patients with chronic myeloid leukaemia (CML) were selected to illustrate the method of analysis.After transplantation, there were 4 possible situations for a patient: disease free, relapse but still alive, death before relapse, and death after relapse. The last 3 events were considered as treatment failure. The results showed that the risk of death before relapse was higher than that of the relapse,especially in the first year after transplantation with competing-risk method. The result of patients with relapse time less than 12 months was much poor by the Kaplan-Meier method. And the multistate survival models were developed, which were detailed and informative based on the analysis of competing risks and Kaplan-Meier analysis. With the multistate survival models, a further analysis on conditional probability was made for patients who were disease free and still alive at month 12 after transplantation. It was concluded that it was possible for an individual patient to predict the 4 possible probabilities at any time. Also the prognoses for relapse either death or not and death either before or after relapse may be given. Furthermore, the conditional probabilities for patients who were disease free and still alive in a given time after transplantation can be predicted.  相似文献   
164.
IntroductionBy implementing dynamic circulating tumor DNA (ctDNA) analysis, we explored the impact of TP53 mutations on tumor evolution and resistance mechanisms to ensartinib in patients with ALK-positive NSCLC.MethodsIn a multicenter phase 2 trial, patients with ALK-positive NSCLC who progressed on crizotinib were treated with ensartinib. Blood samples for ctDNA analysis were collected at baseline, cycle 3 day 1, and progression disease (PD) and analyzed with a 212-gene panel.ResultsA total of 440 samples were collected from 168 patients. Baseline TP53 mutations (20.2%) significantly correlated with inferior progression-free survival (4.2 mo versus 11.7 mo, p < 0.0001). Patients with TP53 mutations had higher mutation load than those without TP53 mutations at baseline (13.79 ± 3.72 versus 4.67 ± 0.39, p < 0.001). Although there was no significant difference in mutation load between these groups at cycle 3 day 1 (5.89 ± 2.25 versus 3.72 ± 0.62, p = 0.425), patients with mutated TP53 developed more mutations at PD (7.07 ± 1.25 versus 3.20 ± 0.33, p = 0.003). Frequency and abundance of secondary ALK mutations G1269A, G1202R, and E1210K increased markedly at PD than baseline. In patients without secondary ALK mutations, we identified ALK-independent resistance mechanisms including bypass signaling activation, downstream effector protein reactivation, epithelial-mesenchymal transformation, and epigenetic dysregulation.ConclusionsOur study highlighted the advantage of ctDNA analysis for monitoring tumor evolution. TP53 mutations promoted genetic evolution and accelerated occurrence of resistance. We also unveiled ALK-dependent resistance mechanisms, mainly by G1269A, G1202R, and E1210K mutations, and ALK-independent resistance mechanisms to ensartinib.  相似文献   
165.
Background: Resection of oligometastases improves survival in metastatic colorectal cancer (mCRC). It is unclear whether the benefit is consistent for BRAF V600E mutant (MT) and wild type (WT) mCRC. This retrospective analysis explores the influence of BRAF MT on survival after metastasectomy. Methods: Overall survival (OS) and recurrence-free survival (RFS) for BRAF MT and WT mCRC were evaluated. Survival was also analyzed in the cohort of BRAF MT with or without metastasectomy. Results: Five hundred and thirteen patients who had undergone metastasectomy were identified, 6% were BRAF-MT. Median age 63. Median OS in BRAF MT vs WT: 25.7 vs 48.5 months (hazard ratio [HR] 1.95; 1.18-3.22). However, difference was not significant in a multivariate model. Right primary tumor, intact primary, >1 metastatic site, non-R0 resection, peritoneal metastasis, and synchronous metastasis were independent predictors of worse OS. Among 364 patients with RFS data there was no difference between BRAF MT and WT (16 vs 19 months, p=0.09). In another cohort of 158 BRAF-MT patients, OS was significantly better after metastasectomy compared to “no metastasectomy” (HR 0.34; 0.18-0.65, P= 0.001). Proficient mismatch repair status showed a trend toward worse survival after metastasectomy in BRAF MT (HR 1.71, P = 0.08). Conclusion: OS did not differ after metastasectomy between BRAF MT and WT in a multivariate model. Median OS was >2 years in this study after metastasectomy among BRAFV600E MT patients suggesting a survival benefit of metastasectomy in this group where systemic therapeutic options are limited. Metastasectomy may be considered in carefully selected BRAF-MT patients.  相似文献   
166.
Sixty percent of newly diagnosed cancers occur in older adults and more complex planning is required to sustain quality care for older populations. Individualized care incorporating geriatric assessment can predict early mortality and treatment toxicity for older cancer patients. We mapped and summarized the available evidence on the integration of geriatric assessment into clinical oncology practice, and ascertained which domains have been implemented. We systematically searched bibliographic databases and trial registries for reports of clinical studies, clinical practice guidelines, systematic and non-systematic reviews, and grey literature published in English. We gathered data on study characteristics, geriatric domains and strategies evaluated, and relevant study objectives and findings. From a total of 10,124 identified citations, 38 articles met our eligibility criteria, 3 of which were clinical practice guidelines. Nearly half of these articles came from the United States. Domains of the geriatric assessment implemented in studies ranged from 1 to 12, with varied combinations. We identified 27 studies on strategies for implementing geriatric assessment and 24 studies on feasibility of implementing geriatric assessment, into clinical oncology practice. We also identified 3 main geriatric assessment models: 2 from the United States and 1 from Australia. Furthermore, we identified 2 reviews that reported varied components of geriatric assessment models. There is increasingly robust evidence to implement formal geriatric assessment in oncology practice. There remains a great deal of variation in the tools recommended to address each of the domains in a geriatric assessment, with only 1 guideline (American Society of Clinical Oncology guideline) settling on a specific best practice.Protocol registration: Open Science Framework osf.io/mec93.  相似文献   
167.
Background and objectivesRoutine lymphadenectomy (LND) for resectable hepatocellular carcinoma (HCC) remains controversial. We evaluated national LND trends to identify pre-operative factors associated with node-positive disease to determine which patients might benefit from LND.MethodsWe identified HCC patients in the National Cancer Database (NCDB) treated with surgical resection between 2004 and 2015. Demographic, operative, pathologic, and survival data were compared. Multivariable regression was performed to determine preoperative predictors of pathologic nodal disease.ResultsOf 8095 total resected patients, 1442 (17.8%) underwent hepatectomy with LND. Patients who received LND had higher preoperative clinical T (T3-T4: 20.0% vs 12.1%, p < 0.001) and N (N1: 3.3% vs 0.6%, p < 0.001) stages. The strongest independent predictor of pathologic nodal disease was clinical N stage (OR 106.54, CI 44.10–257.42). Survival was highest in patients whose surgeons omitted LND or were found with LND to be node-negative on final pathology (p < 0.001). Clinical node positivity had high negative predictive value (97.9%) but moderate positive predictive value (56.3%) in estimating pathologic nodal status. Conclusions: Defining preoperative clinical nodal status is imperative in HCC patients. Clinical node positivity was the strongest predictor of pathologic nodal disease and its associated worse prognosis. LND can be considered selectively in clinically node-positive patients.  相似文献   
168.
Vγ9Vδ2 T cells are attractive effector cells for immunotherapy with potent cytotoxic activity against a variety of malignant cells. However, the effect of Vγ9Vδ2 T cells on chemotherapy-resistant acute myeloid leukemia (AML) blasts, especially highly refractory leukemia stem cells (LSCs) is still unknown. In this study, we investigated the effect of cytotoxicity of allogeneic Vγ9Vδ2 T cells on chemotherapy-resistant AML cell lines, as well as on primary AML blasts and LSCs obtained from refractory AML patients. The results indicated that Vγ9Vδ2 T cells can efficiently kill drug-resistant AML cell lines in vitro and in vivo, and the sensitivity of AML cells to Vγ9Vδ2 T cell–mediated cytotoxicity is not influenced by the sensitivity of AML cells to chemotherapy. We further found that Vγ9Vδ2 T cells exhibited a comparable effect of cytotoxicity against LSCs to primary AML blasts. More importantly, we revealed that the CD226–extracellular signal–regulatory kinase1/2 (ERK1/2)–lysosome-associated membrane protein 1 (LAMP1) pathway is an important mechanism for Vγ9Vδ2 T cell–induced cytotoxicity against AML cells. First, Vγ9Vδ2 T cells recognized AML cells by receptor-ligand interaction of CD226–Nectin-2, which then induced ERK1/2 phosphorylation in Vγ9Vδ2 T cells. Finally, triggering the movement of lytic granules toward AML cells induced cytolysis of AML cells. The expression level of Nectin-2 may be used as a novel marker to predict the susceptibility/resistance of AML cells to Vγ9Vδ2 T cell treatment.  相似文献   
169.
Background: The relationship between living conditions in urban and rural areas during childhood and subsequent inflammatory bowel disease (IBD) remains controversial.

Aim: To explore the association between environmental exposures early in life and the subsequent risk of IBD.

Methods: Literature searches were conducted in the following databases: PubMed, EMBASE, and Conference Proceedings Citation Index. Studies were analyzed separately using rate ratios (RRs) or odds ratios (ORs) with 95% confidence intervals.

Results: The search strategy identified 15 studies. Of these, 9 studies explored the association between urban exposure during childhood and ulcerative colitis (UC), and 12 and 4 studies explored this relationship with Crohn’s disease (CD) and IBD, respectively. A meta-analysis showed that the pooled ORs estimated for the case–control studies of UC, CD, and IBD were 1.16 (0.83, 1.61), 1.45 (1.45, 1.85), and 1.34 (1.11, 1.62), respectively. The pooled RR estimated for the cohort studies of CD and IBD was 1.48 (1.17, 1.87). The stratified analysis and meta-regression showed significant relationships between CD and living conditions in case–control studies published during 2010–2017 and in non-European countries (< 0.05).

Conclusions: Living conditions during childhood are positively associated with the subsequent development of IBD. Urban living environment is more common among those with CD than UC.  相似文献   

170.
目的探讨利福昔明对肠易激综合征(irritable bowel syndrome,IBS)患者的临床疗效。方法计算机检索中国生物医学文献数据库(CBM)(2001年1月-2013年10月)及外文数据库Pub Med(2001年1月-2013年10月),收集利福昔明治疗IBS的所有随机对照试验(RCT),并对所有资料进行Meta分析。结果共纳入5个RCT,2 124例患者。Meta分析结果显示:利福昔明实验组总体疗效优于对照组,能够有效缓解IBS患者全部症状(OR=1.61,95%CI:1.35~1.93),且无明显异质性(P=0.32,I2=14%)。对于次要结局指标腹胀缓解,仅3个RCT收集该有效数据,表明利福昔明实验组相对于对照组能有效缓解患者腹胀(OR=1.62,95%CI:1.35~1.96),且无明显异质性(P=0.39,I2=1%)。发生药物不良反应较少,利福昔明实验组和对照组副反应发生率相比,差异无统计学意义(P0.05)。结论利福昔明在提高IBS的总体疗效及缓解腹胀症状等方面疗效显著,且副作用发生率低。  相似文献   
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