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51.
Objective: To summarize the clinical outcomes of 117 human vitrified blastocyst transfer cycles and to determine the impact factors.Methods: In IVF-ET cycles, supernumerary embryos were cultured to 5-Day(D5) or 6-Day(D6), blastocysts of various stages were cryopreserved by vitrification using cryoloops. Survival rate and clinical pregnancy rate were observed.Results: A total of 312 blastocysts were thawed in 117 frozen embryo transfer cycles, the survival rate was 90.7% (283/312) after thawing. After the transfer of 230 blastocysts in 115 cycles, 69.6% (80/115) of the women got clinically pregnant, and 17.5% (14/80) of them suffered from miscarriage, 39 healthy babies were born in 28 deliveries, and the other 38 pregnancies are ongoing. The implantation rate was 47.4% (109/230). In 107 transfer cycles with 2 hatched blastocysts transferred in each cycle, 72.9% (78/107) got clinically pregnant, while in 8 cycles with 1 or no hatched blastocysts in the two transferred blastocysts, the clinical pregnancy rate is 25%(2/8). The clinical pregnancy rates were not statistically different between natural (77.4%, 24/31) or artificial endometrium preparation (66.7%, 56/84) cycles. Conclusions: These findings suggest that blastocyst vitrification is effective in terms of implantation rate and pregnancy outcome. Transferring of two hatched blastocyst can achieve a higher pregnancy rate. 相似文献
52.
准分子激光角膜切削术治疗近视的并发症 总被引:3,自引:0,他引:3
为分析准分子激光角膜切削术(PRK)治疗近视的并发症,对139例(257眼)PRK术后随访半年至一年。结果表明:术后一年,低中度和高度组各有1眼最佳矫正视力丢失二行,分别占2.5%和3.3%;低中度和高度组的角膜上皮下1级混浊分别为10.81%和15.16%,2级混浊分别为2.73%和0%;激素性高眼压,在发生率最高的3个月时,可分别达24.37%和25.32%,但这种反应性的眼压升高只是暂时的,容易控制;过矫和散光增加的发生率均较低,主要与术者的经验有关。随着术者经验的提高、手术设计的完善及术后用药的研究,这些并发症会降到最低水平。PRK是安全、有效的。 相似文献
53.
54.
Spectral slope of vowels produced by tracheoesophageal speakers 总被引:1,自引:0,他引:1
Spectra of vowels were analyzed to determine whether differences exist between the spectral slope of vowels produced by tracheoesophageal (TE) speakers and normal speakers and, if so, to quantify such differences. The linear predictive autocorrelation method was used to calculate smoothed spectra and the spectra were normalized with respect to a low frequency component. Comparisons between normalized spectral energy within a selected high frequency range revealed that energy within this frequency range for vowels produced by TE speakers was significantly higher than that produced by normal speakers. A least-square distance matching procedure was used to quantify speaker group differences in the spectral slope of vowels. Average spectra of vowels produced by the normal speakers could be matched to average spectra of vowels produced by the TE speakers by decreasing the spectral slope of their vowels by 2-3 dB/octave. 相似文献
55.
本文应用“冷沉淀”法制备纤维组织粘合剂。对纤维组织粘合剂中主要成份和含量进行了测定,并测定了主要理化性质,建立了动物实验模型,观察了实验兔对纤维粘合剂的反应。 相似文献
56.
用平板沉降法测定驻广州部队营区春季大气微生物含量。结果表明,营区大气微生物含量较高(10 311CFU/m~3)。驻市区部队营区大气微生物含量高于近郊营区,建议加强环境卫生监督、监测,控制环境污染。 相似文献
57.
Meng-Liang Zhou Ji-Xin Shi Chun-Hua Hang Hui-Lin Cheng Xiao-Ping Qi Lei Mao Ke-Fei Chen Hong-Xia Yin 《Journal of cerebral blood flow and metabolism》2007,27(9):1583-1592
Nuclear factor-kappaB (NF-kappaB) plays a key role in inflammation, which is involved in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH). In the present study, we assessed the potential role of NF-kappaB in regulation of cerebral vasospasm. Nuclear factor-kappaB DNA-binding activity was measured in cultured vascular smooth muscle cells (VSMCs) treated with hemolysate and pyrrolidine dithiocarbamate (PDTC, 80 micromol/L), an inhibitor of NF-kappaB. Forty-two rabbits were divided into three groups: control, SAH, and PDTC groups (n=14 for each group). The caliber of the basilar artery was evaluated. Nuclear factor-kappaB DNA-binding activity and the gene expression levels of cytokines and adhesion molecules in the basilar artery were measured. Immunohistochemical study was performed to assess the expression and localization of tumor necrosis factor (TNF)-alpha, intercellular adhesion molecule (ICAM)-1, and myeloperoxidase (MPO). It was observed that NF-kappaB DNA-binding activity was significantly increased by treatment with hemolysate in cultured VSCMs, but this increase was suppressed by pretreatment with PDTC. Severe vasospasm was observed in the SAH group, which was attenuated in the PDTC group. Subarachnoid hemorrhage could induce increases of NF-kappaB DNA-binding activity and the gene expression levels of TNF-alpha, interleukin (IL)-1 beta, ICAM-1, and vascular cell adhesion molecule (VCAM)-1, which were reduced in the PDTC group. Immunohistochemical study demonstrated that the expression levels of TNF-alpha, ICAM-1, and MPO were all increased in the SAH group, but these increases were attenuated in the PDTC group. Our results suggest that NF-kappaB is activated in the arterial wall after SAH, which potentially leads to vasospasm development through induction of inflammatory response. 相似文献
58.
高血压患者左室舒张功能与左室肥厚的关系及随龄改变 总被引:1,自引:0,他引:1
为探讨原发性高血压 (以下简称高血压 )患者的左室舒张功能和左室肥厚的关系及其随龄改变 ,抽取 1995年 2月至 2 0 0 2年 7月间门诊高血压患者 4 81例为高血压组 ,以同期体检健康者 2 54 3例为对照组 ,年龄 10~ 80岁 ,并将原发性高血压患者分为 3级 ,每级中按性别分 2组。采用惠普 2 50 0彩色多普勒超声诊断系统检测 2组的室间隔厚度、左室后壁厚度、E/A等指标。使用SPSS软件进行统计学处理分析。结果 :高血压和正常对照组相比E/A显著下降 ,室间隔和左室后壁显著增厚 (P <0 .0 1)。 2个组的E/A均随年龄下降 ,而室间隔厚度随年龄增厚 ,且室间隔厚度和E/A呈显著负偏相关 (P <0 .0 1)。在高血压分级组中 ,Ⅰ~Ⅲ级高血压组中男性的室间隔厚度均厚于女性 (均P <0 .0 1) ,Ⅰ、Ⅱ级高血压组中男性的左室后壁厚度厚于女性 (P <0 .0 5,P <0 .0 1) ,Ⅰ级高血压组中女性的E/A低于男性 (P <0 .0 5)。提示 :左室舒张功能随着年龄的增加而降低 ,而且和高血压左室肥厚呈负偏相关关系 ,性别对其也有一定的影响 相似文献
59.
目的 :比较梅花髓内针和交锁髓内钉治疗股骨干骨折的疗效。方法 :采用梅花针和交锁髓内钉内固定治疗股骨干骨折共 70例 ,比较两组的固定方法、术后处理、愈合时间、肢体与关节功能恢复情况、适应症的选择以及交锁髓内钉的应用体会。结果 :随访 10月~ 2 4月 ,骨折全部愈合 ,梅花针组 4 7例 ,平均愈合时间 7.5个月 ;交锁髓内钉组平均愈合时间 6 .5个月。肢体关节功能恢复 :梅花针组术后肢体成角畸形 15°2例 ,占 4 % ;膝关节活动 <70°3例 ,占 6 %。交锁髓内钉组 ,无成角畸形 ,膝关节活动均恢复正常。结论 :梅花髓内针最好的适应症是股骨干峡部的短斜或横行新鲜骨折 ;交锁髓内钉适应症较广泛 ,可用于所有的股骨干新鲜和陈旧性骨折 ,愈合时间较梅花针短 ,功能恢复良好 ,疗效明显优于梅花髓内针。 相似文献
60.
目的 探讨N -乙酰半胱氨酸 (NAC)治疗不同病期慢性阻塞性肺疾病 (COPD)的疗效。方法 49例稳定期、急性发作期COPD患者 ,随机分为观察组 (2 5例 )和对照组 (2 4例 ) ,观察组除给予常规治疗外 ,加用NAC(每次 2 0 0mg ,3/d ,连用 2个月 ) ;对照组仅给予常规治疗。治疗前后观察所有患者外周血淋巴细胞DNA损伤程度。结果 治疗前后比较 ,观察组稳定期、急性发作期DNA损伤明显降低 ,差异有显著性 (P <0 .0 5)。对照组稳定期DNA损伤程度亦有一定程度的改善 ,但差异无显著性 (P >0 .0 5) ,急性发作期DNA损伤程度降低 ,差异有显著性 (P <0 .0 5)。结论 COPD患者体内存在氧化 -抗氧化失衡 ,抗氧化治疗可降低COPD患者外周血淋巴细胞DNA损伤程度 ,急性发作期出现氧化应激。 相似文献