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排序方式: 共有8492条查询结果,搜索用时 15 毫秒
1.
目的 考察注射用丹参多酚酸(SAFI)对脑缺血大鼠急性期用药的可行性,明确大鼠脑缺血再灌注后脑血流的变化及其与远期运动功能恢复之间的相关性。方法 将Wistar大鼠随机分为假手术组、模型组及SAFI (21 mg·kg-1)组。SAFI组根据不同给药时机又分为3个亚组,分别是再灌后立即给药组(SAFI 0周)、再灌后1周给药组(SAFI 1周)、再灌后2周给药组(SAFI 2周),每组每天给药1次,连续ip 7 d,为保持一致性,其余时间均ip生理盐水,假手术组及模型组分别ip等量生理盐水。采用线栓法构建大鼠脑缺血再灌注模型,假手术组仅分离血管。通过观测大鼠一般状态、评估大鼠神经功能和脑梗死体积百分比考察SAFI急性期给药的药效作用;利用激光多普勒技术检测大鼠局部脑血流量(rCBF);通过转棒实验和步态实验分析大鼠的运动能力;通过Pearson相关性分析方法评估不同时间点的脑血流变化与远期运动功能恢复之间的相关性。结果 与模型组比较,SAFI 0周组大鼠的神经功能评分显著降低(P<0.01),脑梗死体积百分比显著降低(P<0.01),rCBF显著提升(P<0.05、0.01),死亡率明显下降;与模型组比较,SAFI 0周组大鼠在转棒仪上跌落潜伏期显著增加(P<0.05、0.01),SAFI 0周组大鼠在步态仪上运动速度显著增加(P<0.01),四肢的摆动时间、站立时间和步态周期显著下降(P<0.05、0.01),四肢(除左后肢外)的步幅显著增加(P<0.05、0.01)。与SAFI 1、2周组比较,SAFI 0周组脑梗死体积百分比显著降低(P<0.01),死亡率降低,rCBF显著升高(P<0.05、0.01),明显促进了神经行为学功能及运动功能的恢复。Pearson相关性分析结果表明脑缺血再灌注损伤后早期的脑血流恢复与远期运动功能呈线性相关。结论 SAFI在缺血急性期给药具有一定的可行性;脑缺血后梗死周边区域血流恢复对远期运动功能的恢复至关重要。  相似文献   
2.
ObjectivesOsteoclasts can sense the surface topography of materials. However, it is difficult to identify the structural factors that affect osteoclast formation and its function. Furthermore, we hypothesized that the type of osteoclast precursor cells also affects osteoclastogenesis in the materials. In this study, we investigated the effects of defined micro/nanoscale patterns on osteoclastogenesis from bone marrow cells (BMCs).MethodsVarious cyclo-olefin polymer (COP) patterns were prepared using nanoimprinting. The effects of shape, size, and height of the patterns, and the wettability of the patterned surfaces on osteoclastogenesis from BMCs were evaluated in vitro.ResultsOsteoclast formation was promoted on pillars (diameter, 1 μm or 500 nm; height, 500 nm). Notably, osteoclastogenesis from BMCs was better promoted on hydrophobic pillars than on hydrophilic pillars. In contrast, decreased osteoclast formation was observed on the nanopillars (diameter, 100 nm; height, 200 nm).ConclusionsWe demonstrated the promotion of osteoclast formation from BMCs on hydrophobic pillars with diameters of 1 μm and 500 nm. Some cellular behaviors in the patterns were dependent on the type of osteoclast precursor cells. The designed patterns are useful for designing the surface of dental implants or bone replacement materials with a controllable balance between osteoblast and osteoclast activities.  相似文献   
3.
目的 探究酸蚀处理对复合树脂表面封闭剂封闭效果的影响。方法 在140颗离体牙的颊、舌侧分别制备标准V类洞,进行复合树脂充填后随机分为7组(n=20):不作表面封闭(C组);不酸蚀,Permaseal封闭(P0组);15 s酸蚀+Permaseal封闭(P15组);30s酸蚀+Permaseal封闭(P30组);不酸蚀,G-coat封闭(G0组);15 s酸蚀+G-coat封闭(G15组)及30 s酸蚀+G-coat封闭(G30组)。每组中10颗离体牙进行冷热循环老化处理(5 ~ 55℃,1 000次循环,停留时间30 s),另10颗在生理盐水中浸泡24 h后直接进行微渗漏评价。以染料渗入法评价微渗漏程度。结果 任何条件下,P0组、P15组、P30组的组间比较冠方微渗漏等级无显著性升高或降低(P> 0.05);冷热循环条件下,P30组较P0组龈方微渗漏等级显著升高(P< 0.05),G0组、G15组较G30组冠方微渗漏等级显著降低(P< 0.05),G0组较G30组龈方微渗漏等级显著降低(P< 0.05)。结论 (1)酸蚀处理对G-coat的封闭效果有显著影响,不作酸蚀处理可获得最佳封闭效果。(2)酸蚀处理对Permaseal在充填体冠方的封闭效果没有显著影响,对龈方的封闭效果有显著影响,延长酸蚀时间,龈方封闭效果有下降趋势。  相似文献   
4.
BackgroundThe tumor suppressor, protein phosphatase 2A (PP2A), is downregulated in hepatoblastoma. We aimed to examine the effects of two novel compounds of the tricyclic sulfonamide class, ATUX-3364 (3364) and ATUX-8385 (8385), designed to activate PP2A without causing immunosuppression, on human hepatoblastoma.MethodsAn established human hepatoblastoma cell line, HuH6, and a human hepatoblastoma patient-derived xenograft, COA67, were treated with increasing doses of 3364 or 8385, and viability, proliferation, cell cycle and motility were investigated. Cancer cell stemness was evaluated by real-time PCR and tumorsphere forming ability. Effects on tumor growth were examined using a murine model.ResultsTreatment with 3364 or 8385 significantly decreased viability, proliferation, cell cycle progression and motility in HuH6 and COA67 cells. Both compounds significantly decreased stemness as demonstrated by decreased abundance of OCT4, NANOG, and SOX2 mRNA. The ability of COA67 to form tumorspheres, another sign of cancer cell stemness, was significantly diminished by 3364 and 8385. Treatment with 3364 resulted in decreased tumor growth in vivo.ConclusionNovel PP2A activators, 3364 and 8385, decreased hepatoblastoma proliferation, viability, and cancer cell stemness in vitro. Animals treated with 3364 had decreased tumor growth. These data provide evidence for further investigation of PP2A activating compounds as hepatoblastoma therapeutics.  相似文献   
5.
《Dental materials》2022,38(8):1376-1384
ObjectivesWhen consumed in excess, acidic foods and beverages can cause dental erosions leading to irreversible loss of tooth substance. In many cases, prosthetic rehabilitation of the damaged teeth is mandatory. The aim of this in vitro study was to investigate, for the first time on this scale, the resistance of various commonly used self-adhesive resin luting cements (Bifix SE, VOCO; G-Cem LinkAce, GC; RelyX Unicem, 3 M Oral Care; SpeedCEM Plus, Ivoclar ) against acidic media, and to find out whether they can withstand long-term exposure. These results were compared with an adhesive resin luting cement (Panavia V5, Kuraray) that functioned as reference gold standard. Furthermore we applied area roughness parameters for surface texture analysis in the present investigation, to highlight their advantages for investigations on the surface quality of resin luting cements.MethodsSix specimens with identical diameter (10 mm) and thickness (3 mm) were prepared from each self-adhesive and adhesive resin luting cement and forwarded to an incubation in various acidic media for a period of 232 h. Conductivity and pH-values of each acidic medium was analyzed for each material group prior (t 0) and after exposure (t 1). The specimens were examined for Vickers microhardness and surface quality. For the evaluation of surface roughness, the parameters Sa, Sdr, Spc Spk, Sk, and Svk were investigated by using different filtered surfaces (S-L; S-F) according to ISO 25 178. Statistical analysis was conducted at a significance level of α = 0.050.ResultsFor the evaluation of the acid resistance of self-adhesive resin luting cements investigations on conductivity and pH-value assessment of storage solution appear unsuitable, while the assessment of microhardness and surface analysis revealed valid data. It could be shown that changes in surface texture of the resin luting cements can be determinend in qualitative and quantitative manner. While the microhardness and surface quality of some resin luting cements hardly changed, others showed significantly reduced values in microhardness and changes in their surface quality (p < 0.001).SignificanceThe data of the current study emphasize the relevance of interactions between resin luting cements and acids and suggest further laboratory and clinical studies to elucidate its impact on the clinical performance of the materials investigated  相似文献   
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目的 调查ICU患者血液净化专用中心静脉导管的封管情况,并比较不同等级医院之间的差异。 方法 2020年9月,采用便利抽样法对23个省份117所医院共228名ICU护士长进行在线调查,调查内容包括医院及ICU的基本信息、ICU患者血液净化专用中心静脉导管的封管现状。结果 共回收222份有效问卷。肝素溶液是ICU患者血液净化专用中心静脉导管最常用的封管液,其次是枸橼酸钠溶液,尿激酶溶液使用最少。肝素溶液的浓度以1 250 U/ml为主,枸橼酸钠溶液的浓度以4%为主。封管液剂量以1倍导管容量居多;护士多在每次血液净化结束后封管,封管方式以正压联合脉冲封管为主;封管前均进行回抽,回抽次数以2次居多,每次回抽量以2倍导管容量居多。非三级医院的ICU在封管液浓度、封管液剂量、封管频次、封管前回抽次数、每次回抽量等方面均与三级医院不同,差异具有统计学意义(均P<0.05)。结论 各ICU在血液净化专用中心静脉导管封管液的种类、浓度、剂量及封管频次等方面不尽相同,建议制订ICU患者血液净化专用中心静脉导管封管护理实践标准,规范护士封管行为。  相似文献   
9.
A factitious disorder leading to the self-infliction of highly counter-intuitive burns was diagnosed in a middle-aged female. The injuries were otherwise alleged to have been sustained by assault inflicted upon her by an unknown person. The case was diagnosed by medico-legal interpretation of injuries, in spite of a highly deceptive and concocted history by the patient and her husband. The entity was unique in being associated with magnificent primary, secondary and tertiary gains. The exploitation of the morbid sequel to malinger by the patient, and the involvement of the husband for the prolongation of the illness of his wife for financial gains as gaslighting was highly unusual. The self-infliction of injuries over hands is seen in factitious disorder. However, a combination of a guarded self-immersion of the hands and feet in a corrosive by an illiterate female, followed by malingering to earn livelihood is unprecedented in factitious disorders. The delayed presentation which required amputation of all the limbs to save the life of the patient is a glaring highlight of this case.  相似文献   
10.
《Immunobiology》2022,227(6):152298
PLPPs (Phospholipid phosphatases) are widely expressed in different human tissues, regulate cell signal transduction, and are overexpressed in cancers such as gliomas, pancreatic adenocarcinoma, lung adenocarcinoma, and so on. As a member of the PLPP family, PLPP2 (phospholipid phosphatase 2) plays a vital role in the occurrence and development of breast cancer, but its mechanism is still unclear. Our research found that PLPP2 was overexpressed in breast cancer, and the higher expression level of PLPP2 showed a worse prognosis for breast cancer patients. Further analysis showed that overexpression of PLPP2 affected the expression of CDC34 (cell-division cycle 34), LSM7 (Like-Smith 7), and SGTA (small glutamine-rich tetratricopeptide repeat-containing protein alpha) through EMT (epigenetic-mesenchymal transition) related pathways to promote the occurrence and development of breast cancer. In vitro, silencing PLPP2 significantly reduced the proliferation, invasion, and migration abilities of human breast cancer cells MDA-MB-231. ER+ is a common subtype of breast cancer. Furthermore, we found that the overexpression of PLPP2 was significantly related to the poor prognosis of ER+ breast cancer. These results indicate that PLPP2 has value as a potential therapeutic target for breast cancer, especially for ER+ breast cancer.  相似文献   
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