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71.
本文介绍He-Ne激光沿经络自动照射仪的结构、特点,分析了激光与组织相互作用的物理效应和生物效应,提出了该仪器在针灸临床中的应用。  相似文献   
72.
目的:观察鼻腔内激光照射疗法对缺血性脑血管病低切粘度及红细胞压积的影响,方法:采用鼻腔内激光照射治疗仪治疗60例病人,治疗前后抽空腹静脉血测定低切粘度及红细胞压积。结果:临床及实验室结果表明,鼻腔内激光照射疗法对于降低低切粘度及红细胞压积有显著作用(p〈0.001),结论:鼻腔内激光照射疗法可改变血液流变学及脑的血液循环,使受伤的神经组织再生,为急性缺血性脑血管病提供一种新的治疗方法。  相似文献   
73.

目的:探讨分析糖尿病视网膜病变(diabetic retinopathy,DR)患者全视网膜激光光凝术(panretinal photocoagulation,PRP)治疗后1a视网膜神经纤维层(retinal nerve fiber layer,RNFL)厚度的变化。

方法:选取2014-05/2017-06在我院行PRP治疗的92例92眼DR患者,采用OCT的DISC CIRCLE程序,测量分析以视盘为中心、直径3.45mm范围DR患者PRP术前和术后1a(采用Follow-Up程序自动追踪模式)视盘周围RNFL厚度,按视盘上方(S)、下方(I)、鼻侧(N)、颞侧(T)4个象限分区所得的数值进行统计分析。

结果:DR患者PRP术后1a较术前视盘周围上方、下方、鼻侧、颞侧和全周平均RNFL厚度明显变薄,且差异有统计学意义(均P<0.05)。

结论:PRP治疗可导致视网膜RNFL变薄,临床上应充分重视和考虑RNFL的损伤,更好地保护视网膜神经细胞的机能对DR治疗具有重要意义。  相似文献   

74.
AIM: To observe the effects of femtosecond laser-assisted excimer laser in situ keratomileusis combined with accelerated corneal cross-linking (FS-LASIK Xtra) on corneal densitometry after correcting for high myopia. METHODS: In this prospectively study, 130 patients underwent FS-LASIK or FS-LASIK Xtra for high myopia. Their right eyes were selected for inclusion in the study, of which 65 cases of 65 eyes in the FS-LASIK group, 65 patients with 65 eyes in the FS-LASIK Xtra group. Patients were evaluated for corneal densitometry at 1, 3, and 6mo postoperatively using Pentacam Scheimpflug imaging. RESULTS: Preoperative differences in corneal densitometry between the FS-LASIK and FS-LASIK Xtra groups in different ranges were not statistically significant (P>0.05). Layer-by-layer analysis revealed statistically significant differences in the anterior (120 μm), central, and total layer corneal densitometry between the FS-LASIK and FS-LASIK Xtra groups at 1 and 3mo postoperatively (all P<0.05), the FS-LASIK Xtra group is higher than that of the FS-LASIK group. Analysis of different diameter ranges showed statistically significant differences between the FS-LASIK group and the FS-LASIK Xtra group at 1mo postoperatively in the ranges of 0–2, 2–6, and 6–10 mm (both P<0.05); At 3mo postoperatively, the FS-LASIK Xtra group is higher than that of the FS-LASIK group in the ranges of 0–2 and 2–6 mm (P<0.05). At 6mo postoperatively, there were no statistically significant differences in corneal densitometry between the FS-LASIK group and the FS-LASIK Xtra group in different diameter ranges (all P>0.05). CONCLUSION: There is an increase in internal corneal densitometry during the early postoperative period after FS-LASIK Xtra for correction of high myopia. However, the densitometry values decreased to the level of conventional FS-LASIK at 6mo after surgery, with the most significant changes observed in the superficial central zone.  相似文献   
75.
Severe shot peening (SSP) was used on additive manufactured 316L by laser powder bed fusion. The effect of the post processing on the surface features of the material was analyzed through residual stress measurements, tensile testing, hardness-depth profiles, and fatigue testing by flexural bending. The results showed that SSP can be utilized to form residual stresses up to −400 MPa 200 μm below the surface. At the same time, a clear improvement on the surface hardness was achieved from 275 HV to near 650 HV. These together resulted in a clear improvement on material strength which was recorded at 10% improvement in ultimate tensile strength. Most significantly, the fatigue limit of the material was tripled from 200 MPa to over 600 MPa and the overall fatigue strength raised similarly from a low to high cycle regime.  相似文献   
76.
This work is a first approach to investigate the role of spatial dispersion in photonic hypercrystals (PHCs). The scope of the presented analysis is focused on exploiting nonlocality, which can be controlled by appropriate design of the structure, to obtain new light generation effects in a distributed feedback (DFB) laser based on PHC, which are not observable under weak spatial dispersion. Here, we use effective medium approximation and our original model of threshold laser generation based on anisotropic transfer matrix method. To unequivocally identify nonlocal generation phenomena, the scope of our analysis includes comparison between local and nonlocal threshold generation spectra, which may be obtained for different geometries of PHC structure. In particular, we have presented that, in the presence of strong spatial dispersion, it is possible to obtain spectrally shifted Bragg wavelengths of TE- and TM-polarization spectra, lowered generation threshold levels for both light polarizations, generation of light of selected light polarization (TE or TM), or simultaneous generation of TE- and TM-polarized waves at different frequencies with controllable spectral separation, instead of single mode operation anticipated with local approach.  相似文献   
77.
Ge2Sb2Te5 (GST225) looks to be a promising material for rewritable memory devices due to its relatively easy processing and high optical and electrophysical contrast for the crystalline and amorphous phases. In the present work, we combined the possibilities of crystallization and anisotropic structures fabrication using femtosecond laser treatment at the 1250 nm wavelength of 200 nm thin amorphous GST225 films on silicon oxide/silicon substrates. A raster treatment mode and photoexcited surface plasmon polariton generation allowed us to produce mutually orthogonal periodic structures, such as scanline tracks (the period is 120 ± 10 μm) and laser-induced gratings (the period is 1100 ± 50 nm), respectively. Alternating crystalline and amorphous phases at the irradiated surfaces were revealed according to Raman spectroscopy and optical microscopy studies for both types of structures. Such periodic modulation leads to artificial optical and electrophysical anisotropy. Reflectance spectra in the near infrared range differ for various polarizations of probing light, and this mainly results from the presence of laser-induced periodic surface structures. On the other hand, the scanline tracks cause strong conductivity anisotropy for dc measurements in the temperature range of 200–400 K. The obtained results are promising for designing new GST225-based memory devices in which anisotropy may promote increasing the information recording density.  相似文献   
78.
目的:以不同程度地减少固定桥桥体的颊舌径,观察固定桥基牙牙周膜的受力情况,了解桥体的颊舌减径是否可以减少固定桥基牙牙周的受力.方法:采用三维激光扫描与Marc软件结合的方式,建立双端固定桥桥体颊舌径分别为正常时的100%(M1)、90%(M2)、66.7%(M3)和50%(M4)的4个三维有限元模型,施加载荷,计算并分析牙周膜支持组织中的应力分布状况.结果:垂直均布加载时基牙牙周膜的受力随着咬合面积的减小而呈规律性的下降,但在垂直集中加载和斜向加载时牙周膜受力变化不显著.结论:单纯的颊舌减径并不能有效地起到降低牙周受力的作用.  相似文献   
79.
目的: 比较308 nm准分子激光联合富血小板血浆(platelet-rich plasma,PRP)与单用308 nm准分子激光治疗白癜风的有效性与安全性.方法: 检索PubMed、Embase、Web of Science、Cochrane Library、中国知网、万方、维普、中国生物医学文献数据库中关于308 ...  相似文献   
80.
氦-氖激光耳穴照射加针灸治疗寻常型痤疮36例   总被引:3,自引:0,他引:3  
观察氦 氖激光耳穴照射加针灸治疗寻常型痤疮的临床疗效 ,6 8例寻常型痤疮患者随机分为观察组 (36例 ,以氦 氖激光耳穴照射加针灸治疗 )和对照组 (32例 ,单纯针灸治疗 )。结果 :观察组治愈率为 77 8% ,对照组为 4 6 9% ,P <0 0 5。提示氦 氖激光耳穴照射加针灸治疗寻常型痤疮疗效确切。  相似文献   
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