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921.
研究不同Alpha角对多焦点人工晶状体(MIOL)植入术后视觉质量的影响,指导功能性IOL的应用。方法:前瞻性临床研究。选取2016年12至2018年10月就诊于潍坊眼科医院行白内障超声乳化吸除联合MIOL植入术患者56例(74眼),根据Alpha角大小(角膜上视轴与光轴的距离α)分为3组: A组12眼(0 mm<α≤0.2 mm),B组38眼(0.2 mm<α≤0.4 mm),C组24眼(α>0.4 mm)。术后随访3个月,记录裸眼远、中、近视力以及调制传递函数、眩光、光晕等情况。数据采用卡方检验、方差分析进行统计。结果:B组和C组光晕和眩光发生率高于A组,差异有统计学意义(χ2 =38.372,P=0.01); 3组间术后3个月远、中、近视力比较差异无统计学意义(均P>0.05);3组间MTF值在0~30 c/d范围差异无统计学意义(P>0.05);夜间远视、重影、混合焦点、星芒的发生率差异均无统计学意义(均 P>0.05)。结论:当Alpha角大于0.4 mm时,植入MIOL会增加眩光和光晕的发生,所以Alpha角>0.4 需谨慎考虑使用MIOL。 相似文献
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923.
Objective Identification of the risk factors for extraordinary hidden blood loss (HBL) could clarify the underlying causes and provide more appropriate management. This study aims to identify the predictors of HBL in spinal surgery. 相似文献
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926.
Comparative evaluation of the impact of minimally invasive preparation vs. conventional straight‐line preparation on tooth biomechanics: a finite element analysis
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Keyong Yuan Chenguang Niu Qian Xie Wenxin Jiang Li Gao Zhengwei Huang Rui Ma 《European journal of oral sciences》2016,124(6):591-596
Minimally invasive endodontics emphasizes preservation of a maximal amount of healthy tooth tissue. However, whether the tooth structure preserved by minimally invasive endodontics can maintain higher fracture resistance is unclear. This study aimed to compare the biomechanics on teeth after minimally invasive (MI) preparation and straight‐line (SL) preparation using finite element analysis. Six finite element analysis models of a mandibular first molar were constructed and divided into two groups (MI and SL). Two loads of 250 N, one vertically stimulating the vertical masticatory force and the other given 45° to the longitudinal axis of the tooth, were applied. Stresses in the teeth were calculated and analyzed. Under both vertical and 45° loads, the greatest stresses were located at the margin of the cavities on the occlusal surfaces. The stress concentration areas of teeth with minimally invasive access cavities were smaller than those of teeth prepared with straight‐line opening in coronal and cervical areas. The stress concentration points in the cervical areas increased with the increase of canal taper in the coronal third. Minimally invasive access preparation reduced the stress distribution in crown and cervical regions. A smaller taper cervical enlargement caused lower stress in the cervical region. 相似文献
927.
Katarzyna Miekus Marta Pawlowska Ma?gorzata Seku?a Grazyna Drabik Zbigniew Madeja Dariusz Adamek Marcin Majka 《Oncotarget》2015,6(12):10086-10101
Cervical cancer is one of the leading causes of death among women suffering from tumors. Current treatment options are insufficient. Here, we investigated the MET receptor as a potential molecular target in advanced cervical cancer. Downregulation of MET receptor expression via RNA interference in different cervical carcinoma cell lines dramatically decreased tumor growth and forced tumor differentiation in vivo. MET receptor silencing also led to a dramatic decrease in cell size and a decrease in proliferation rate under normal and stress conditions. MET receptor downregulation also resulted in decreased cyclin D1 and c-myc levels but did not increase apoptosis. Subsequent experiments showed that downregulation of the MET receptor decreased the expression of a key regulator of the epithelial-to-mesenchymal transition, SLUG. and increased the expression of E-cadherin, a hallmark of the epithelial phenotype. Moreover, MET downregulation impairs expression and signaling of CXCR4 receptor, responsible for invasive phenotype.Taken together, our results strongly suggest that the MET receptor influences the oncogenic properties of cervical carcinoma cells in vitro and in vivo. These findings highlight a unique role of the MET receptor in cervical carcinoma cells and indicate the MET receptor as a potential therapeutic target for advanced cervical carcinoma. 相似文献
928.
Menglin Ma Abhijit Gurjar James R. Theoret Jorge P. Garcia Juliann Beingesser John C. Freedman Derek J. Fisher Bruce A. McClane Francisco A. Uzal 《Infection and immunity》2014,82(7):2958-2970
The ability of Clostridium perfringens type C to cause human enteritis necroticans (EN) is attributed to beta toxin (CPB). However, many EN strains also express C. perfringens enterotoxin (CPE), suggesting that CPE could be another contributor to EN. Supporting this possibility, lysate supernatants from modified Duncan-Strong sporulation (MDS) medium cultures of three CPE-positive type C EN strains caused enteropathogenic effects in rabbit small intestinal loops, which is significant since CPE is produced only during sporulation and since C. perfringens can sporulate in the intestines. Consequently, CPE and CPB contributions to the enteropathogenic effects of MDS lysate supernatants of CPE-positive type C EN strain CN3758 were evaluated using isogenic cpb and cpe null mutants. While supernatants of wild-type CN3758 MDS lysates induced significant hemorrhagic lesions and luminal fluid accumulation, MDS lysate supernatants of the cpb and cpe mutants caused neither significant damage nor fluid accumulation. This attenuation was attributable to inactivating these toxin genes since complementing the cpe mutant or reversing the cpb mutation restored the enteropathogenic effects of MDS lysate supernatants. Confirming that both CPB and CPE are needed for the enteropathogenic effects of CN3758 MDS lysate supernatants, purified CPB and CPE at the same concentrations found in CN3758 MDS lysates also acted together synergistically in rabbit small intestinal loops; however, only higher doses of either purified toxin independently caused enteropathogenic effects. These findings provide the first evidence for potential synergistic toxin interactions during C. perfringens intestinal infections and support a possible role for CPE, as well as CPB, in some EN cases. 相似文献
929.
The fibrillar structure and sub-micron diameter of electrospun nanofibers can be used to reproduce the morphology and structure
of the natural extracellular matrix (ECM). The objective of this work was to investigate the effect of fiber alignment on
osteogenic differentiation of bone marrow stromal (BMS) cells. Random and aligned poly(l-lactide) (PLLA) nanofibers were produced by collecting the spun fibers on a stationary plate and a rotating wheel, respectively,
as the ground electrode. Morphology and alignment of the BMS cells seeded on the fibers were characterized by SEM. The effect
of fiber orientation on osteogenic differentiation of BMS cells was determined by measuring alkaline phosphatase (ALPase)
activity, calcium content, and mRNA expression levels of osteogenic markers. There was a strong correlation between the fiber
and cell distributions for the random (p = 0.16) and aligned (p = 0.81) fibers. Percent deviation from ideal randomness (PDIR) values indicated that cells seeded on the random fibers (PDIR = 6.5%)
were likely to be distributed randomly in all directions while cells seeded on the aligned fibers (PDIR = 86%) were highly
likely to be aligned with the direction of fibers. BMS cell seeded on random and aligned fibers had similar cell count and
ALPase activity with incubation time, but the calcium content on aligned fibers was significantly higher after 21 days compared
to that of random fibers (p = 0.003). Osteopontin (OP) and osteocalcin (OC) expression levels of BMS cells on fibers increased with incubation time.
However, there was no difference between the expression levels of OP and OC on aligned vs. random fibers. The results indicate
that BMS cells aligned in the direction of PLLA fibers to form long cell extensions, and fiber orientation affected the extent
of mineralization, but it had no effect on cell proliferation or mRNA expression of osteogenic markers. 相似文献
930.
中西医结合治疗急性脑梗死临床观察 总被引:1,自引:0,他引:1
目的:观察中西医结合治疗急性脑梗死的临床疗效。方法:100例随机分成对照组40例和治疗组60例,两组均用血塞通注射液、丹红注射液并常规对症治疗,治疗组加用中药汤剂治疗。结果:总有效率治疗组96.67%、对照组85.00%,两组比较有显著差异(P<0.05)。结论:中西医结合治疗脑梗死疗效明显。 相似文献