聚左旋乳酸在皮肤紧致的应用及研究进展

聚左旋乳酸是一种生物相容性较好的可降解高分子材料，近年来在医疗行业中应用价值较高， 因其具有的无毒、无刺激且可塑性较高等特点在医美领域应用应用广泛。因此，本文通过查阅和整理相关 文献，对聚左旋乳酸对皮肤紧致的作用机制、使用方法及当前应用现状和前景进行综述，以阐明聚左旋乳 酸在皮肤紧致的应用概况，旨在为聚左旋乳酸在皮肤紧致的临床应用提供参考。     

晶须碳酸钙/聚L-乳酸复合材料的合成与实验研究

目的 合成晶须碳酸钙/聚L-乳酸复合材料,并评价其生物相容性、力学性能及降解性。方法 采用溶液共混法聚合晶须碳酸钙/聚L-乳酸复合材料,对其进行初始强度及降解后的力学测定、体外细胞共培养及降解速率的测定。结果 复合材料对细胞无毒性,聚L-乳酸加入晶须碳酸钙后,力学性能均有不同程度提高且降解失重率减小。结论 晶须碳酸钙与聚L-乳酸复合后,提高了材料的力学性能,延缓了降解,并具有一定的生物活性。     

注射用聚左旋乳酸在体表软组织充填中的应用现状

聚左旋乳酸(Poly-L-lactin acid,PLLA)在医学领域已有充分应用.2004年,美国FDA批准塑然雅注射用聚左旋乳酸作为一种填充材料治疗与艾滋病相关的面部萎缩.此后,多个注射用聚左旋乳酸品牌相继在不同国家或地区获批上市.近年来,注射用聚左旋乳酸被用来改善多部位软组织凹陷或缺失引起的外观不满意.本文从注射...     

晶须碳酸钙／聚L-乳酸复合材料的合成与实验研究

目的 合成晶须碳酸钙／聚L-乳酸复合材料，并评价其生物相容性、力学性能及降解性。方法 采用溶液共混法聚合晶须碳酸钙／聚L-乳酸复合材料，对其进行初始强度及降解后的力学测定、体外细胞共培养及降解速率的测定。结果 复合材料对细胞无毒性，聚L-乳酸加入晶须碳酸钙后，力学性能均有不同程度提高且降解失重率减小。结论晶须碳酸钙与聚L-乳酸复合后，提高了材料的力学性能，延缓了降解，并具有一定的生物活性。     

聚左旋乳酸在面部年轻化中的应用进展

聚左旋乳酸（PLLA）是近年来被广泛运用到医学领域的一种新型生物可降解高分子材料，主 要应用于可吸收缝合线、骨修复材料、软组织修复支架等。此外，PLLA还可以用于填充注射，改善和重 建皮肤，抵抗衰老，促进组织的再生和修复等，是临床应用于面部年轻化的主要手段。本文将从PLLA的 化学与生物特性、面部年轻化的需求，以及PLLA在面部填充注射中的作用机制及应用情况等方面进行综 述，以阐明PLLA在面部年轻化中的应用前景，为医学美容领域的发展和创新提供有力的支持。     

注射用聚左旋乳酸在体表软组织充填中的应用现状

当前随着社会经济的不断发展,人们对于自身形象的关注度也在与日剧增,有很多体表软组织 下凹陷的患者会选择应用医美手段来达到机体体表软组织充填的效果。其中,聚左旋乳酸作为一种生物可 降解高分子材料,不仅适用于面部区域的填充治疗,同样还可应用在于痤疮瘢痕、踝部瘢痕、臀部瘢痕及 手背部瘢痕的修复。因此,本文将针对聚左旋乳酸在体表软组织修复的最新相关研究作一综述,以期为相 关研究提供一定参考价值。     

“美速得”聚L-乳酸微球治疗面部皱纹的临床效果

1999年,以聚L-乳酸制作的一种新型填充剂"newfill"在欧洲获得认证许可并投放市场。接着,聚L-乳酸(商品名:sculptra)在1999年也在欧洲获得治疗皮肤皱纹、疤痕、皮肤老化等症状的认证。它是一种可注射的聚乳酸制剂,亦来源于α-羟基酸家族中一种可生物降解和生物相溶的合成聚合物,在2004年8月其获得美国食品和药物管理局快速评审后批准用于治疗人类免疫缺陷病毒相关的面部脂肪萎缩。目前已通过美国食品和药物管理局(FDA)批准,用于治疗包括脂肪萎缩、面部消瘦、皮下脂肪萎缩所致的面颊、眼和颞部下陷等病症的注射材料。研究表明,Sculptra可显著增加皮肤厚度和面部脂肪萎缩部位的组织量,使脂肪萎缩部位恢复原状。并且有较好的安全性。现我国上海信晟医疗制品有限公司生产的"美速得"注射用聚L-乳酸微球,由上海医药工业研究院研制,和Sculpra具有相同的材料、结构和成分,主要用于面部皮下脂肪和皮肤胶原蛋白流失的矫正,消除面部皱纹。现已通过中国药品和生物制品鉴定所的注册检验,报国家药监局注册。现正在进行临床阶段试验。目的探讨"美速得"聚L-乳酸微球治疗面部皱纹的临床效果。研究方法自2008年至2009年,从因面部皱...     

应用可吸收聚羟基乳酸网包裹破裂脾脏

我院1996年10月至1997年10月应用美国强生公司生产的可吸收聚羟基乳酸网(Vicryl Mesh,VM)包裹外伤性破裂脾脏,取得满意效果.     

聚左旋乳酸微针导入改善肤质的效果研究

为分析聚左旋乳酸微针导入对肤质的改善效果，本研究选取2022年1月-6月于我院行肤质改善 干预的12例患者为研究对象，使用聚左旋乳酸微针进行干预。结果显示，接受面部肤质改善的6例患者治 疗后面部肤质的整体改善效果较好，提亮效果十分理想，治疗后棕色斑区域评分为（76.58±23.71）分，低于 治疗前的（110.21±24.36）分，差异有统计学意义（P＜0.05）；接受手部肤质干预的2例患者肤质为C级轻微 改善，其手部褶皱以及细纹明显减少；接受颈部肤质干预的4例患者肤质改善效果也十分理想。可见，使 用聚左旋乳酸微针来对面部、颈部以及手部等肤质进行干预，不仅有良好的肤质改善效果，还具有一定安 全性，应用效果理想。     

用国产聚-DL-乳酸棒行骨折内固定动物实验

目的：模拟低应力部位小管状骨骨折髓腔内固定条件，研究聚-DL-乳酸棒髓腔内生物降解及机械强度的变化，为其在手外科指骨骨折固定的临床应用提供实验依据。方法：兔尺挠骨骨折固定模型中，右侧用PDLLA棒髓内固定，对照侧用克氏针固定。术后2、4、6、8、12周处死，作大体观察、X-Bay摄片、可吸收材料力学、分子量的测定。结果：粘均分子量降解和机械强度衰减之间有良好的相关性；12周时剪切强度为30．74MPa、抗弯强度为50．53MPa；粘均分子量为初始的41．35％。2组骨折大体观察、X—Bay无明显差异。结论：该国产PDLLA棒有足够的机械强度，在临床低应力部位骨折尤其在手外科指骨骨折内固定中，应有很大发展价值。     

Effects of lactic acid and glycolic acid on human osteoblasts: a way to understand PLGA involvement in PLGA/calcium phosphate composite failure

The use of degradable composite materials in orthopedics remains a field of intense research due to their ability to support new bone formation and degrade in a controlled manner, broadening their use for orthopedic applications. Poly (lactide-co-glycolide) acid (PLGA), a degradable biopolymer, is now a popular material for different orthopedic applications and is proposed for use in tissue engineering scaffolds either alone or combined with bioactive ceramics. Interference screws composed of calcium phosphates and PLGA are readily available in the market. However, some reports highlight problems of screw migration or aseptic cyst formation following screw degradation. In order to understand these phenomena and to help to improve implant formulation, we have evaluated the effects of PLGA degradation products: lactic acid and glycolic acid on human osteoblasts in vitro. Cell proliferation, differentiation, and matrix mineralization, important for bone healing were studied. It was found that the toxicity of polymer degradation products under buffering conditions was limited to high concentrations. However, non-toxic concentrations led to a decrease in cell proliferation, rapid cell differentiation, and mineralization failure. Calcium, whilst stimulating cell proliferation was not able to overcome the negative effects of high concentrations of lactic and glycolic acids on osteoblasts. These effects help to explain recently reported clinical failures of calcium phosphate/PLGA composites, but further in vitro analyses are needed to mimic the dynamic situation which occurs in the body by, for example, culture of osteoblasts with materials that have been pre-degraded to different extents and thus be able to relate these findings to the degradation studies that have been performed previously.     

腹部外科血瘀证患者血浆氨基酸谱与血瘀兼证关系的研究

目的：探讨腹部外科血瘀证各兼证型的氨基酸代谢。方法：对３６例腹部外科血瘀证患者行血浆氨基酸谱分析。结果：气滞血瘀组支链氨基酸（ＢＣＡＡ）、芳香氨基酸（ＡＡＡ）含量以及支链氨基酸／芳香氨基酸（ＢＣＡＡ／ＡＡＡ）比值与对照组无差异,气虚血瘀组ＢＣＡＡ较对照组明显降低,ＢＣＡＡ／ＡＡＡ比值显著降低,湿热血瘀组ＢＣＡＡ及ＡＡＡ均明显增高。结论：腹部外科血瘀证各兼证型氨基酸代谢不同,临床工作中应充分认识以提     

伊妍仕与玻尿酸注射美容的区别

注射和光电等微创疗法在抗衰方面的效果良好，且恢复时间较短，目前已成为热门医疗美容 项目。软组织填充剂进行组织增容已有20余年，有多种软组织填充剂可选择，如非动物源性透明质酸 （NASHA）、羟基磷灰石钙（微晶瓷）和聚左旋乳酸（PLLA）填充剂等，不同填充剂的疗效存在一定差 异。本文在阅读相关文献的基础上，对伊妍仕? 和玻尿酸注射美容的区别作一综述，以期为临床医美填充 材料的选择提供一定参考价值。     

小儿上尿路结石286例临床分析

目的:进一步探讨新疆地区小儿泌尿系结石的临床特征.方法:对收治的286例小儿上尿路结石患儿的临床资料进行分析.其有明显的区域、族群分布和结石成分特征;均经影像学确诊;239例行开放手术取石治疗.结果:开放手术取石239例,一次取尽结石率89.0%,术后2～12年复发41(14.3%)例,术中术后未发现严重并发症.结论:影像学检查是诊断小儿泌尿系结石的主要手段,磁共振尿路成像对小儿尿路结石形态诊断,具有较好的实用性和优越性;开放手术适应证广、技术成熟,仍是目前小儿泌尿系结石的主要治疗方法.     

The prospects for amino acid infusion

Amino acid preparations for intravenous infusion are indispensable materials in parenteral nutrition. We have surveyed the progress and problems related to such preparations. In recent years, the necessity of various amino acid preparations suitable for different morbid states and/or ages has been the subject of much interest. In practice, several new amino acid preparations for specific uses have been proposed.     

Bioceramics in ossicular replacement prostheses: a review

For many decades, bioceramic materials have been used in a variety of biomedical applications due to their biocompatibility, hardness, wear resistance and compressive strength properties. Bioceramic materials, including Bioglass, glass ceramic materials, and hydroxyapatite, have used to create total ossicular replacement prostheses and partial ossicular replacement prostheses. This review describes design factors associated with middle ear implants as well as clinical use of bioceramic materials in middle ear implants.     

Ultrafiltration techniques and CPB: what we know and what we think we know

Unfortunately there have been very few prospective randomized studies comparing the clinical outcomes of patients treated with large volume ultrafiltration. Given the shortage of impressive clinical outcome data and the varying results of mediator removal studies, the application of ultrafiltration as a therapeutic technique is still a controversial topic. A few researchers have suggested that different membrane materials may have significantly different mediator removal potential. One important future direction for research in this area should include a comprehensive comparison of different membrane materials with regard to their clinical performance.     

Effects of an Intra-Epididymal and Intra-Scrotal Copper Device on Rat Spermatozoa

The effects of implantation of an intra-epididymal (IECD) and intrascrotal (ISCD) copper device on rat testicular and epididymal spermatozoa and the copper contents in its various reproductive tissues were studied and compared with another group of animals bearing the copper device and fed supplemental ascorbic acid. The motility of cauda epididymal spermatozoa in vitro in the presence of different concentrations of copper ions was also investigated. The results revealed that the in vitro decrease in motility was more rapid with increasing concentrations of copper sulphate solutions and the addition of ascorbic acid inhibited the motility of the spermatozoa much more rapidly than the copper sulphate solution alone, probably due to the strong acidic properties of ascorbic acid which caused a rapid fall in pH.
In the copper device bearing rats, the count, motility, fertilizing capacity, and metabolism of epididymal spermatozoa were reduced which has been correlated with alterations in their morphology. An accumulation of copper occurred in several reproductive tissues, but recovery to almost normal levels was obtained by feeding ascorbic acid to copper implanted rats. The data supports the view that ascorbic acid has a beneficial effect in copper toxicity. Although the intraepididymal copper implantation was found to be a more effective male contraceptive device than the intra-scrotal, further work is necessary in terms of reversibility of the effects and easy removal of the device.     

How have wear testing and joint simulator studies helped to discriminate among materials and designs?

Historically, hip joint simulators most often have been used to model wear of a bearing surface against a bearing surface. These simulators have provided highly accurate predictions of the in vivo wear of a broad spectrum of bearing materials, including cross-linked polyethylenes, metal-on-metal, ceramic-on-ceramic, and others in development. In recent years, more severe conditions have been successfully modeled, including jogging, stair climbing, ball-cup micro separation, third-body abrasion, and neck-socket impingement. These tests have served to identify improved materials and to eliminate some with inadequate wear resistance prior to their clinical use. Simulation of the knee joint is inherently more complex than it is for the hip. It is more difficult to compare the results of laboratory tests with actual clinical performance, due to the lack of accurate in vivo measures of wear. Nevertheless, knee simulators, based on force control or motion control, have successfully reproduced the type of surface damage that occurs in vivo (eg, burnishing, scratching, pitting) as well as the size and shapes of the resultant wear particles. Knee simulators have been used to compare molded versus machined polyethylene components, highly cross-linked polyethylenes, fixed versus mobile bearings, and oxidized zirconia and other materials, under optimal conditions as well as more severe wear modes, such as malalignment, higher loading and activity levels, and third-body roughening.     

Studies of host response to orthopedic implants and biomaterials.

The use of implanted biomaterials in orthopedic surgery has increased rapidly during the past two decades. Total joint replacement of the hip or knee joint has become common treatment; at the same time, an increasing number of fractures are treated with osteosynthesis. The original Charnley low-friction arthroplasty of the hip is still widely used and gives in large series excellent results. Aseptic loosening of this arthroplasty has been thought to be due to wear debris of the methylmethacrylate used for fixation of the implants, or to debris generated from wear of the polyethylene socket. To date, many different materials have been tried in order to reduce wear and generation of macrophage irritating submicron sized particles, or to provide more biocompatible components. However, trials to improve the methylmethacrylate cement or to invent better polyethylenes have often failed. Diamond coating of the metallic components seems promising: there is less wear and diamond is very biocompatible in bulk and small particulate form. Biodegradable implants have also been found useful in treating fractures. Bioactive bioabsorbable materials may also make possible a tissue engineering approach and can be used as carriers for selected drugs and cytokines. Because many promising materials and designs have failed in clinical use, extensive theoretical and experimental testing is mandatory before introducing new materials and implants in a clinical setting.