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961.
不同的劳动就业制度具有不同的内容规定;计划就业和市场就业是两种不同的就业制度,在我国不同历史时期都实践过这两种就业制度。比较分析两种制度对于推动深化改革具有重要的意义。  相似文献   
962.
microRNAs (miRNAs) are important regulators of tumor development and progression. In this study, we aimed to explore the expression and role of miR-622 in hepatocellular carcinoma (HCC). We found that miR-622 was significantly downregulated in human HCC specimens compared to adjacent noncancerous liver tissues. miR-622 downregulation was significantly associated with aggressive parameters and poor prognosis in HCC. Enforced expression of miR-622 significantly decreased the proliferation and colony formation and induced apoptosis of HCC cells. In vivo studies demonstrated that miR-622 overexpression retarded the growth of HCC xenograft tumors. Bioinformatic analysis and luciferase reporter assays revealed that miR-622 directly targeted the 3′-untranslated region (UTR) of mitogen-activated protein 4 kinase 4 (MAP4K4) mRNA. Ectopic expression of miR-622 led to a significant reduction of MAP4K4 expression in HCC cells and xenograft tumors. Overexpression of MAP4K4 partially restored cell proliferation and colony formation and reversed the induction of apoptosis in miR-622-overexpressing HCC cells. Inhibition of JNK and NF-κB signaling phenocopied the anticancer effects of miR-622 on HCC cells. Taken together, miR-622 acts as a tumor suppressor in HCC and restoration of miR-622 may provide therapeutic benefits in the treatment of HCC.  相似文献   
963.
964.
Numerous medications are used to treat hyperpigmentation. However, several reports have indicated that repeated application of some agents, such as rhododendrol (RD), raspberry ketone (RK) and monobenzone (MB), can be toxic to melanocytes. Although these agents had severe side effects in human trials, no current in vitro methods can predict the safety of such drugs. This study assessed the in vitro effects of five depigmentary compounds including leukoderma‐inducing agents. In particular, we determined the effects of different concentrations and exposure times of different depigmentary agents on cell viability and melanogenesis in the presence and absence of ultraviolet B (UVB) radiation. Concentrations of RD, RK and MB that inhibit melanogenesis are similar to concentrations that are cytotoxic; however, concentrations of rucinol (RC) and AP736 that inhibit melanogenesis are much lower than concentrations that are cytotoxic. Furthermore, the concentrations that cause toxic effects depend on exposure duration, and prolonged exposure to RD, RK and MB had more cytotoxic effects than prolonged exposure to RC and AP736. The cytotoxic effects of RD and RK appear to be mediated by apoptosis due to increased expression of caspase‐3 and caspase‐8; UVB radiation increased the cytotoxicity of these agents and also increased caspase activity. Our results indicate that different leukoderma‐inducing compounds have different effects on the viability of normal epidermal melanocytes and suggest that the in vitro assay used here can be used to predict whether an investigational compound that induces leukoderma may lead to adverse effects in human trials.  相似文献   
965.
Schwann cells are not only myelinating cells, but also function as immune cells and express numerous innate pattern recognition receptors, including the Toll-like receptors. Injury to peripheral nerves activates an inflammatory response in Schwann cells. However, it is unclear whether specific endogenous damage-associated molecular pattern molecules are involved in the inflammatory response following nerve injury. In the present study, we demonstrate that a key damage-associated molecular pattern molecule, high mobility group box 1(HMGB1), is upregulated following rat sciatic nerve axotomy, and we show colocalization of the protein with Schwann cells. HMGB1 alone could not enhance expression of Toll-like receptors or the receptor for advanced glycation end products(RAGE), but was able to facilitate migration of Schwann cells. When Schwann cells were treated with HMGB1 together with lipopolysaccharide, the expression levels of Toll-like receptors and RAGE, as well as inflammatory cytokines were upregulated. Our novel findings demonstrate that the HMGB1 pathway activates the inflammatory response in Schwann cells following peripheral nerve injury.  相似文献   
966.
PurposeTo report the effectiveness and safety of transcatheter arterial sclerosing embolization (TASE) for the treatment of parotid infantile hemangiomas that did not respond appreciably to propranolol.Materials and MethodsA total of 21 infants (12 male and 9 female) with large propranolol-resistant infantile hemangiomas in the parotid region were enrolled in this study. During TASE, the feeding arteries of the lesions were embolized using pingyangmycin-lipiodol emulsion and polyvinyl alcohol particles (300–500 μm) to reduce the blood flow rate. All children were followed up as outpatients at 2 weeks and monthly thereafter. The curative effect was evaluated at the 1- and 3-month follow-up visits.ResultsNine lesions were located on the right side of the parotid gland, whereas 12 were located on the left side. The feeding arteries in all patients originated from branches of the external carotid artery. TASE was technically successful in all patients. The mean (± SD) maximal diameter of the hemangiomas significantly decreased from 6.50 cm ± 2.28 before treatment to 3.56 cm ± 1.84 at 1 month after TASE (P <. 05). Three months after TASE, the mean maximal diameter further significantly decreased to 1.94 cm ± 1.58 (P <. 05). During the follow-up period, 16 cases were rated as excellent and 5 as good; no recurrence or serious complications were noted. Minor side effects, such as slight pain, mild fever, and tissue swelling, were observed.ConclusionsTASE significantly decreased the size of the parotid hemangiomas with minor side effects during a short follow-up period.  相似文献   
967.
目的:系统评价Ki67表达比例对乳腺癌患者预后的影响,尤其是对无病生存期(DFS)的影响。为临床应用提供循证医学依据。方法:计算机检索PubMed、Embase、Web of Science、Cochrane Library、中国期刊全文数据库(CNKI)、维普数据库(VIP)、万方数据库以及中国生物医学文献数据库(CBM)。应用RevMan 5.3软件对所纳入的数据进行统计学分析。结果:共纳入8篇文献,合计15 643例患者。Meta分析结果显示,纳入文献中的Ki67高比例表达组患者的DFS(HR=1.86,95%CI=1.31~2.65)要低于Ki67低比例表达组,差异有统计学意义。亚组分析中,以种族分亚组的结果与上述类似,差异也有统计学意义;以Ki67表达临界值分亚组,Ki67表达临界值为30%的亚组差异没有统计学意义,表达临界值为其他值的亚组差异有统计学意义。结论:本研究Meta分析显示,Ki67是乳腺癌的一种不良预后因子,Ki67高比例表达的患者有着更低的DFS。  相似文献   
968.
目的:分析256排CT低剂量扫描在肺部小结节鉴别诊断中的应用价值。方法:选取我院自2017年2月—2019年2月收治的46例肺部小结节患者,于患者入院时采用常规剂量对患者进行CT扫描检查,并于1周后进行CT低剂量扫描复查。对比患者经过两次扫描后的肺部小结节数量、结节内部的特征以及结节周围的变化。结果:采用常规剂量扫描与低剂量扫描肺部小结节数量相比差异较小(P>0.05);常规剂量扫描与低剂量扫描小结节内部特征比较差异性较小(P>0.05);常规剂量扫描与低剂量扫描诊断结构比较差异较小(P>0.05)。结论:采用256排CT低剂量扫描肺部小结节患者,对常规剂量的进行扫描的价值差异较小,但低剂量CT扫描相对来说辐射更小,值得广泛推广使用。  相似文献   
969.
970.
目的探讨术前白蛋白碱性磷酸酶比值(AAPR)与根治性膀胱切除术后患者总体生存期(OS)的关系。方法回顾性分析2007年1月至2015年12月青岛大学附属医院收治的166例膀胱癌患者的临床病理资料。男148例,女18例。年龄(65.1±9.4)岁。伴高血压病31例、糖尿病14例。体质指数(BMI)(24.00±3.32)kg/m^2。肿瘤单发92例,多发74例。肿瘤直径<3 cm者43例,≥3 cm者123例。合并肾积水33例,无肾积水133例。术前AAPR(0.62±0.23)。根据AAPR的三分位点将患者分为低AAPR组55例,AAPR(0.42±0.09);中AAPR组55例,AAPR(0.58±0.05);高AAPR组56例,AAPR(0.86±0.21)。美国麻醉医师协会(ASA)分级1级4例,2级65例,3级86例,4级11例。根治术前患者均行经尿道膀胱肿瘤切除术,病理诊断均为膀胱癌,高级别144例,低级别22例。166例均行根治性膀胱切除术,其中腹腔镜手术140例,开放手术26例。术中行输尿管皮肤造口55例,回肠代膀胱96例,回肠原位新膀胱15例。将AAPR连续性变量和AAPR分组作为原始模型,调整年龄、肿瘤大小、pT分期、pN分期、肾积水、ASA分级、辅助化疗的数据作为校准模型1,在校准模型1基础上增加BMI、肿瘤数目、病理等级的数据作为校准模型2。采用趋势性检验检测不同AAPR组间危险比(HR)变化趋势。分析不同因素分层的AAPR与OS的关系。采用Kaplan-Meier法绘制生存曲线。采用基于广义相加模型的曲线拟合表示AAPR与OS的关系。结果本组166例中位随访63个月,生存95例,死亡71例。3年生存率为61%,5年生存率为50%。术后病理分期:T1期27例,T2期82例,T3期48例,T4期9例;N0期145例,N1期14例,N2期6例,N3期1例。术后52例行辅助化疗。单因素Cox回归分析结果显示,AAPR(HR=0.09,95%CI 0.022~0.391,P=0.001)、高AAPR组(HR=0.40,95%CI 0.216~0.742,P=0.003)、年龄(HR=2.42,95%CI 1.294~4.531,P=0.006)、肿瘤大小(HR=2.11,95%CI 1.112~4.014,P=0.023)、肿瘤数目(HR=0.62,95%CI 0.378~1.022,P=0.061)、pT3期(HR=8.93,95%CI 3.173~25.114,P<0.001)、pT4期(HR=10.39,95%CI 3.110~34.707,P<0.001)、N1期(HR=2.80,95%CI 1.422~5.531,P=0.003)、N3期(HR=17.06,95%CI 2.192~132.863,P=0.007)、病理分级(HR=0.30,95%CI 0.113~0.817,P=0.019)、肾积水(HR=2.36,95%CI 1.406~3.939,P=0.001)、术后辅助化疗(HR=2.66,95%CI 1.674~4.247,P<0.001)均与术后OS相关。调整年龄、肿瘤大小、pT分期、pN分期、肾积水、ASA分级、辅助化疗、BMI、肿瘤数目、病理分级后,Cox回归分析结果显示,与低AAPR组相比,高AAPR组的死亡风险降低约59%(HR=0.406,95%CI 0.200~0.822,P=0.012),AAPR每升高1个单位,死亡风险下降约80%(HR=0.199,95%CI 0.051~0.779,P=0.020)。趋势性检验结果显示,原始模型和校准模型中,AAPR不同分组间OS的HR下降趋势均有统计学意义(P=0.016),提示两者呈线性关系。调整年龄、肿瘤大小、pT分期、pN分期、肾积水、ASA分级、辅助化疗、BMI、肿瘤数目、病理分级后,曲线拟合图显示,AAPR与OS呈线性相关,随AAPR升高,术后死亡风险下降,OS延长。结论AAPR与膀胱肿瘤患者根治性膀胱切除术后的OS成线性相关,随AAPR升高,患者术后死亡风险下降,OS延长。  相似文献   
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