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911.
912.
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   
913.
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   
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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   
916.
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   
917.
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   
918.
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   
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