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81.
We examined the behavior of human foreskin keratinocytes (HFKs) on reconstituted type IV collagen gel. HFKs survived for several days and the upper layer cells expressed a differentiation marker, involucrin. Apoptosis was induced after involucrin expression while cell proliferation was suppressed. On molecular type IV collagen, integrins shifted from α2β1 to α3β1 during HFK culture. On type IV collagen gel, HFKs initially expressed integrin α2β1, and later expressed integrin α3β1 in the presence of α2β1 did not disappear. Using synthetic peptides, we examined integrin α2-mediated adhesion to type IV collagen gel. Addition of synthetic peptide dose-dependently inhibited cell adhesion both on type IV collagen gel and on molecular type IV collagen. On type IV collagen gel, weaker phosphorylation of focal adhesion kinase, paxillin, and Akt was observed compared with the molecular forms. Based on these observations, we think type IV collagen gel is a novel culture substrate that mimics the physiological environment for HFKs.  相似文献   
82.
张芬熙  洪艳  梁文妹 《解剖学报》2013,44(3):334-338
目的 探讨睾丸支持细胞(SCs)对体外培养人脐带间充质干细胞(hUCMSCs)增殖能力的影响。方法 体外分离培养并鉴定hUCMSCs和SCs;
Transwell-insert系统共培养SCs 和hUCMSCs(共培养组);普通DMEM-F12培养基培养的hUCMSCs作为对照(对照组);添加细胞因子
(白细胞介素-3,粒细胞-巨噬细胞集落刺激因子) 的DMEM-F-12培养基培养的hUCMSCs作为阳性对照 (细胞因子组)。用流式细胞术、免疫细胞
化学等方法检测SCs对hUCMSCs增殖、细胞周期、表面标记分子表达的影响,透射电镜观察细胞超微结构。结果 与对照组相比,共培养组和细胞
因子组hUCMSCs增殖明显加快,以共培养组尤为显著(P<0.05);共培养组和细胞因子组hUCMSCs 表面分子CD29和CD105阳性率均增高;细胞周
期分析显示,共培养组G0/G1期细胞数与对照组相比无明显改变,而细胞因子组略有减少。透射电镜观察对照组与共培养组细胞均呈现原始细胞
的超微结构特点。结论 SCs共培养可促进hUCMSCs增殖,且共培养后仍保持其干细胞特性。  相似文献   
83.
目的 制备兔抗小鼠胚胎干细胞免疫血清,观察其对小鼠胚胎发育的影响。方法 用小鼠胚胎培养基稀释兔抗血清,分别稀释至50倍、100倍、200倍,用其对小鼠8-细胞胚胎进行培养,通过胚胎致密化、囊胚率、胚胎体外贴壁生长、细胞计数、胚胎移植和免疫荧光染色观察胚胎发育状况。 结果 形态学上50倍稀释的抗血清能够抑制8 细胞胚胎的发育甚至使其死亡;100倍稀释的抗血清能够延迟8 细胞胚胎的致密化,并使得胚胎在囊胚化过程中出现空泡化的现象;200倍稀释的抗血清作用不明显。未作免疫处理的兔血清与空白对照组差异不显著。100倍稀释的抗血清能够显著抑制囊胚内细胞团(ICM)的发育、囊胚细胞分布紊乱、胚胎细胞数目减少以及囊胚畸形率增加。虽然囊胚的碱性磷酸酶和Oct4均呈阳性,但经胚胎移植后都不能正常发育。 结论 兔抗小鼠胚胎干细胞免疫血清能够抑制小鼠胚胎致密化过程和囊胚内细胞团的发育,使囊胚出现空泡化,细胞分布紊乱,抑制胚胎着床。  相似文献   
84.
An area critical to safety in an organisation is the perceived and actual culture. National Air Traffic Services (NATS) work closely with large safety-critical industries including various aviation companies to enable them to identify strengths and vulnerabilities with the aim of improving safe practice. NATS have developed a simple free downloadable self-assessment App that individuals can use to assess their own culture perception in their organisation. The App has 16 questions arranged in four domains but to our knowledge it has not been used to date in healthcare. As part of the initiatives to improve staff culture, we evaluated operating theatre colleagues’ safety perception in our large acute NHS Trust in a pilot study using the NATS safety App. Staff downloaded the App to their smart device before completing it. Responses were sent anonymously through the App and collated by NATS. A total of 146 colleagues downloaded and completed the questionnaire. One hundred and seventeen staff (80%) felt encouraged to report safety concerns, but 86% (n = 126) confirmed a lack of available support from healthcare managers. Only 43% of respondents (n = 63) would find it easy to challenge colleagues if they observed unsafe behaviour. This pilot study has identified positive indicators of an evolving NHS safety culture, and some concerns about speaking up, support, and challenging colleagues without fear. These issues are known to occur across healthcare. Further work is needed in the NHS to provide a supportive environment to improve patient safety, and lower hierarchy in surgical teams.  相似文献   
85.
Sputum smear microscopy for the diagnosis of tuberculosis (TB) is cheap and simple but its sensitivity is low. Culture on Löwenstein–Jensen (LJ) is more sensitive but it takes a long time to yield results. Thin-Layer Agar (TLA) culture was suggested as an equally sensitive and faster alternative. We evaluated the performance of TLA for diagnosing TB in Jogjakarta, Indonesia. People with suspected TB presenting from July 2010 to July 2011 to two chest clinics of the National TB Control Programme network of Jogjakarta were eligible for inclusion. A sputum sample was sent to the Gadjah Mada University microbiology laboratory for concentration, smearing, Ziehl–Neelsen staining and culture on LJ and TLA. Sensitivity of cultures was evaluated against a composite reference standard (any positive culture). Time to detection of Mycobacteria was recorded. Out of 1414 samples, 164 (12%) were smear positive, 99 (7%) were scanty and 1151 (81%) were negative. On TLA and LJ respectively, 168 (12%) and 149 (11%) samples were positive, 72 (5%) and 32 (2%) were contaminated (κ = 0.64; 95% CI 0.59–0.69, p <0.01). Using the reference standard, 196 (14%) TB cases were identified. The sensitivity of TLA was 0.86 (95% CI 0.80–0.90), significantly higher (p 0.03) than for LJ (0.76; 95% CI 0.69–0.81). The median time to detection in days was significantly shorter (p <0.01) for TLA (12; 95% CI 11–13) than for LJ (44; 95% CI 43–45). TLA is a rapid and sensitive method for the diagnosis of TB. Implementation studies to evaluate the cost-effectiveness and impact of its introduction into programmatic settings are urgently needed.  相似文献   
86.
目的 探讨人脐带源间充质干细胞(HUC-MSC)条件培养液(CM)对人肝癌HepG2细胞生长的影响.方法 选择2011年2月至2014年1月于中国人民解放军第105医院妇产科分娩的35例足月妊娠剖宫产健康胎儿脐带为研究对象,取其用于分离、培养并扩增HUC-MSC.传代扩增至第3代HUC-MSC融合达80%时,更换培养液,继续培养24 h后收集上清液,即为HUC-MSC-CM备用.将对数生长期的人肝癌HepG2细胞按照随机数字表法随机分成相等的3份,分别于含50%,20%及不含HUC-MSC-CM的培养中培养,并分别纳入高含量组、低含量组和空白对照组.采用倒置显微镜观察人肝癌HepG2细胞生长状态,采用3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐(MTT)法和细胞划痕愈合实验分别检测3组人肝癌HepG2细胞增殖和迁移情况,并采用流式细胞术(FCM)法检测各组细胞的细胞周期变化情况.本研究遵循的程序符合中国人民解放军第105医院人体试验委员会所制定的伦理学标准,得到该委员会批准,脐带获取前,均征得孕妇知情同意,并与之签署临床研究知情同意书.结果 ①所分离的原代HUC-MSC培养至第3代后,细胞形态开始比较均一.②MTT法检测结果显示,人肝癌HepG2细胞培养24,48和72 h时,3组相对吸光度(A)值比较,差异均有统计学意义(F=21.330,6.223,9.345;P=0.004,0.032,0.027),且在这3个时间点,高含量组和低含量组相对A值均显著高于空白对照组,差异均有统计学意义(P<0.05),高含量组相对A值亦显著高于低含量组,差异亦均有统计学意义(P<0.05).③划痕愈合实验结果显示,3组人肝癌HepG2细胞过河时间比较,差异有统计学意义(F=12.860,P=0.025),且高含量组人肝癌HepG2细胞过河时间短于低含量组和空白对照组,差异均有统计学意义(P<0.05),低浓度组人肝癌HePG2细胞过河时间亦短于对照组,差异亦有统计学意义(P<0.05).④FCM法检测人肝癌HepG2细胞周期结果显示,3组G0/G1期和S期人肝癌HepG2细胞比例比较,差异均有统计学意义(F=30.600,30.590;P<0.05).且与空白对照组相比,高含量组和低含量组人肝癌HepG2细胞G0/G1期细胞比例显著降低,S期细胞比例显著增加,差异均有统计学意义(P<0.01);且高含量组G0/G1期细胞比例比低含量组下降更显著,而S期细胞比例显著增加,差异均有统计学意义(P<0.05).结论 HUC-MSC-CM可促进入肝癌HepG2细胞增殖和迁移,并可促进人肝癌HepG2细胞周期G1/S转换.  相似文献   
87.
88.

Objective

To describe returning veterans’ transition experience from military to civilian life and to educate health care providers about culture-centered communication that promotes readjustment to civilian life.

Methods

Qualitative, in-depth, semi-structured interviews with 17 male and 14 female Iraq and Afghanistan veterans were audio recorded, transcribed verbatim, and analyzed using Grounded Practical Theory.

Results

Veterans described disorientation when returning to civilian life after deployment. Veterans’ experiences resulted from an underlying tension between military and civilian identities consistent with reverse culture shock. Participants described challenges and strategies for managing readjustment stress across three domains: intrapersonal, professional/educational, and interpersonal.

Conclusions

To provide patient-centered care to returning Iraq and Afghanistan veterans, health care providers must be attuned to medical, psychological, and social challenges of the readjustment experience, including reverse culture shock. Culture-centered communication may help veterans integrate positive aspects of military and civilian identities, which may promote full reintegration into civilian life.

Practice implications

Health care providers may promote culture-centered interactions by asking veterans to reflect about their readjustment experiences. By actively eliciting challenges and helping veterans’ to identify possible solutions, health care providers may help veterans integrate military and civilian identities through an increased therapeutic alliance and social support throughout the readjustment process.  相似文献   
89.
目的:研究我院ICU科室真菌血症病原菌的分布特点和药敏结果,为真菌血症的临床诊断和抗菌药物治疗提供依据。方法:对我院2014-2018年,5年间ICU科室血培养分离酵母样真菌且符合真菌血症诊断标准的临床资料进行回顾性分析,应用WHONET 5.6软件对菌株分布和药敏结果进行统计。结果:ICU确诊真菌血症患者共129例,致病菌主要为近平滑念珠菌(59株,45.7%)、白色念珠菌(22株,17.1%)、光滑念珠菌(14株,10.9%)和热带念珠菌(12株,9.3%)。真菌血症以男性患者(72.1%)居多,好发于65岁及以上老年(64.3%);重症医学科(55.8%)和老年病房ICU(20.2%)分离率较高。所有菌株对5-氟胞嘧啶和两性霉素B敏感性较高,对唑类药物出现不同程度耐药。结论:我院真菌血流感染以近平滑念珠菌为多见。光滑念珠菌、热带念珠菌、红酵母属对唑类药物的敏感性相对较低。推广质谱、分子生物学等快速鉴定技术,了解真菌血症病原菌对抗菌药物的敏感性,对ICU真菌血流感染患者的早期诊治和预后有着重要意义。  相似文献   
90.
目的:分离培养家兔脂肪干细胞(Adipose-derived stem cells,ASCs),观察体外培养生长特性,并在特定条件下诱导分化,探讨其成脂成骨分化能力。方法:无菌条件下切取家兔腹股沟处脂肪组织,0.25%Ⅰ型胶原酶消化,分离培养原代细胞,取第3代ASCs做实验,用HE染色观察细胞形态,MTT比色法测定细胞生长曲线;用流式细胞仪检测其细胞表面标志物;用油红O染色和茜素红染色鉴定成脂和成骨诱导分化。结果:从家兔脂肪组织中分离获得的ASCs形态为长梭形,成纤维细胞样,生长活力旺盛,具有较强的增殖能力;流式细胞仪分析CD29呈阳性表达,CD31呈阴性表达;成脂诱导的细胞油红O染色阳性,成骨诱导的细胞茜素红染色阳性。结论:本实验分离培养的细胞为ASCs,具有成脂和成骨分化潜能。  相似文献   
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