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1.
强脉冲光治疗浅表(皮肤)血管瘤临床观察   总被引:4,自引:4,他引:0  
目的:观察强脉冲光(IPL)治疗浅表(皮肤)血管瘤的疗效。方法:选择60例浅表(皮肤)血管瘤患者,随机分为治疗组和对照组,治疗组用535nm、580nm强脉冲光治疗皮损,每三周治疗一次,三次为一个疗程;对照组采用波长为532nm的Q开关Nd:YAG激光治疗,每两周治疗一次,三次为一个疗程。观察两组皮损的治愈率、并发症等情况,并行统计学处理。结果:治疗组皮损三次治愈率明显高于对照组(P〈0.01),患处瘢痕形成及炎症性色素沉着发生率均低于对照组。结论:强脉冲光(IPLTM)治疗浅表(皮肤)血管瘤效果满意。  相似文献   
2.
Osteolysis induced by ultrahigh molecular weight polyethylene wear debris has been recognized as the major cause of long-term failure in total joint arthroplasties. In a previous study, the prevalence of intraoperatively identified osteolysis during primary revision surgery was much higher in mobile bearing knee replacements (47%) than in fixed bearing knee replacements (13%). We postulated that mobile bearing knee implants tend to produce smaller sized particles. In our current study, we compared the particle size and morphology of polyethylene wear debris between failed mobile bearing and fixed bearing knees. Tissue specimens from interfacial and lytic regions were extracted during revision surgery of 10 mobile bearing knees (all of the low contact stress (LCS) design) and 17 fixed bearing knees (10 of the porous-coated anatomic (PCA) and 7 of the Miller/Galante design). Polyethylene particles were isolated from the tissue specimens and examined using both scanning electron microscopy and light-scattering analyses. The LCS mobile bearing knees produced smaller particulate debris (mean equivalent spherical diameter: 0.58 microm in LCS, 1.17 microm in PCA and 5.23 microm in M/G) and more granular debris (mean value: 93% in LCS, 77% in PCA and 15% in M/G).  相似文献   
3.
Summary Patients with post-concussional symptoms (PCS) about 6 months after a mild head injury (MHI) were examined for tolerance of light and sound in comparison with concussed patients without PCS and nonconcussed healthy controls. MHI patients with PCS were individually matched with subjects from the two control groups for the time elapsed from the injury, and for age and sex. Using a computerized rating technique, we assessed both the maximal and submaximal levels of lowered tolerance for light and sound over a wide range of stimuli. We found that the MHI patients with PCS 6 months after the trauma (n=11) tolerated significantly less well stimuli of intensities of 71 dB and 500 lx than MHI patients without PCS (n=11) and non-concussed controls (n=11). There were no significant differences in tolerance for light and sound between MHI patients without PCS and the non-injured controls. Decreased tolerance for light and sound may contribute to the persistence of symptoms up to 6 months after a mild head injury. The psychophysical method provides an objective measure for the evaluation of the late persistent postconcussional syndrome.  相似文献   
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5.
In recent years, research on the aetiology of psoriasis has focused on immune aetiopathogenesis. However, in the last few years, research on the immunoloogical changes in psoriasis has failed to mention the lymphatics. Also, studies emphasizing the importance of the dermal lymphatics have neglected the lymphatic changes seen in psoriasis. Therefore, we decided to put this matter back on the agenda. Skin biopsies from 20 patients with psoriasis vulgaris were examined lymphatically by light microscopy using the orcein stain. We found a considerable increase in both number and dilatation in the lymphatics of psoriatic plaques, compared with both the clinically uninvolved skin of the psoriatic patients and also the skin of the control group.  相似文献   
6.
Background Itraconazole is an orally active antifungal lipophilic drug with high affinity for sebum and keratinocytes. Aim The aim of the study was to investigate the routes of percutaneous egression and the sites of cutaneous action/storage of 3H-labelled itraconazole in an experimental animal model. Material and methods Hartley guinea pigs were dosed orally by gavage for 2 consecutive days at 10 mg/kg/day 3H-itraconazole dissolved in polyethylene glycol 200. At various time points after the second gavage, small full-thickness samples of dorsal skin were excised and processed using dry-apposing autoradiography. Results Our research revealed an accumulation of silver grains over the epidermis and its appendages (hair follicle and sebaceous gland), the dermal fat tissue and the hypodermal muscle tissue on tissue sections at 6, 24 and 48 h time intervals, whereas at the remaining time points (96, 168 and 336 h) the silver grain density was markedly decreased to background level. Discussion The present histological distribution data support the current method of oral treatment with itraconazole as the treatment schedule of choice to eradicate infective organisms residing in the deeper skin layers.  相似文献   
7.
光-电一体化技术在美容医学领域的兴起与发展   总被引:9,自引:9,他引:0  
目的介绍光-电一体化技术的机理、适应证的选择、疗效、及并发症和注意事项。方法经文献复习,此项技术的产品有两种类型:①射频与强脉冲光;②射频与激光联合。两种技术发出的能量,分别作用于真皮深层和浅层以及筋膜层,使真皮胶原增厚,以达到皮肤年轻化,并可用于治疗色素沉着、血管病灶、脱毛和痤疮等。电能(RF)40~100J/cm^3,光能15~50J/cm^2。结果根据Fzpatrick皮肤分类和Glogau皱纹分类,选用不同的参数,才能取得好的结果。Bitter和Mulholland报道的Aurora SR设备,皮肤年轻化效果达92%~98%,仅有2%~8%不满意;脱毛效果达80%~85%,20%轻度红斑,24h消失,有8%暂时性色素沉着;下肢静脉扩张最后一次治疗1~6个月,约77%治疗区中有75%~100%扩张血管消失,对桔皮症也取得了较好的效果。结论此项技术的疗效是肯定的,并发症和不良反应少而轻,无不可治愈的不良反应。不同肤色和皱纹选用恰当的治疗参数,是取得满意疗效的保证。  相似文献   
8.
实验性视网膜光化学损伤中的蛋白激酶C   总被引:2,自引:0,他引:2  
目的:研究实验性视网膜光化学损伤中蛋白激酶C(protein kinase C,PKC)活性的改变;探索地塞米松(dexamethasone,DXM)对视网膜中PKC活性的影响。 方法;48只SD大鼠分为对照组和DXM组,后者于光照前3天开始,连续5天腹膜腔注射DXM 1mg/(kg·d)。经(1 900±106.9)Ix的绿色荧光灯(λ=510nm~560nm)连续照射24小时后的6小时和1、3、7、14天,进行视网膜PKC活性检测。 结果:光化学损伤后视网膜中的PKC活性在短暂的上升后即出现持续性的下降;DXM对PKC的活性改变无明显作用。 结论:光化学损伤中的视网膜功能障碍可能与PKC活性的持续降低有关。 (中华眼底病杂志,1997,13:78-80)  相似文献   
9.
The planar fibrous connective tissues of the body are composed of a dense extracellular network of collagen and elastin fibers embedded in a ground matrix, and thus can be thought of as biocomposites. Thus, the quantification of fiber architecture is an important step in developing an understanding of the mechanics of planar tissues in health and disease. We have used small angle light scattering (SALS) to map the gross fiber orientation of several soft membrane connective tissues. However, the device and analysis methods used in these studies required extensive manual intervention and were unsuitable for largescale fiber architectural mapping studies. We have developed an improved SALS device that allows for rapid data acquisition, automated high spatial resolution specimen positioning, and new analysis methods suitable for large-scale mapping studies. Extensive validation experiments revealed that the SALS device can accurately measure fiber orientation for up to a tissue thickness of at least 500 μm to an angular resolution of∼1o and a spatial resolution of±254 μm. To demonstrate the new device’s capabilities, structural measurements from porcine aortic valve leaflets are presented. Results indicate that the new SALS device provides an accurate method for rapid quantification of the gross fiber structure of planar connective tissues.  相似文献   
10.
The present paper reports 11 cases of light chain disease (LCD) sequently found in several citles over Fujian province, Immunological classification of this group of LCD ww as follows: six of me cases belonged to type λ, four of them were type κ, and another one was a double LCD. We found that LCD was common in Fujlan only next to multiple myeloma (MM) of IgG class and accounted for 20% of the total 55 MM cases found in recent yean.It to well known that In matt patients of LCD M protein or Bence Jones proteinemia (BJPemia) to not detectable by conventional electro-phoresis. Our studies show that by making serum protein along with urinary BJP electrophoresis on the same one gel plate the sltuation can be greatly Improved It not only favour* the recognition of smail and faint band or bands of free light chain in serum, but also provides a repid and sensitive way, i. e. , immunofixation, to directly detect urinary light chain on the gel plate Immediately after electrophresis has been run.  相似文献   
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