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101.
Background Various laser and light therapy have been increasingly used for the treatment of acne vulgaris. Patients and methods Twenty patients with facial acne were treated using intense pulsed light (IPL) on one side of the face and pulsed dye laser (PDL) on the other to compare the efficacy and safety of IPL and PDL. Treatment was performed 4 times at 2‐week intervals. Treatment effectiveness was determined using lesion counts, acne severity, patient subjective self‐assessments of improvement, and histopathological examinations, which included immunohistochemical staining for transforming growth factor‐β (TGF‐β). Results Numbers of total acne lesions decreased following both treatments. For inflammatory lesions such as papules, pustules and nodules, IPL‐treated sides showed an earlier and more profound improvement than PDL‐treated sides. However, at 8 weeks after the 4th treatment, a rebound aggravation of acne was observed on IPL‐treated sides. On the contrary, PDL produced gradual improvements during the treatment sessions and these improvements lasted 8 weeks after the 4th treatment. Non‐inflammatory lesions as open and closed comedones also showed improvement following both treatments and PDL‐treated sides showed better improvement as the study proceeded. Histopathological examinations showed amelioration in inflammatory reactions and an increase in TGF‐β expression after both treatments, which were more prominent for PDL‐treated sides. Conclusion Both PDL and IPL were found to treat acne effectively, but PDL showed a more sustained effect. TGF‐β might play a key role in the resolution of inflammatory acne lesions.  相似文献   
102.
4-Hydroperoxycyclophosphamide (4-HC), a commonly used marrow-purging agent, is active against many tumors, but is also toxic to normal marrow progenitors. Amifostine (WR-2721) is a sulfhydryl compound with chemoprotectant activity. Preclinical studies using suspensions of bone marrow and breast cancer cells demonstrated that ex vivo treatment with amifostine followed by 4-HC resulted in protection of marrow progenitors, with no compromise in the antitumor effect of 4-HC. This fact stimulated the development of a clinical trial. Bone marrow was harvested from 15 poor-prognosis breast cancer patients and randomly assigned to ex vivo treatment with amifostine followed by 4-HC (amifostine + 4-HC), or treatment with 4-HC alone. High-dose chemotherapy was then administered followed by infusion of the purged autologous bone marrow support (ABMS). Leukocyte engraftment, defined as a white blood cell count > or = 1 x 10(9)/L, was achieved in an average of 26 days for patients whose marrow was purged with amifostine + 4-HC versus 36 days for patients whose marrow was purged with 4-HC alone (P = .032). The average number of platelet transfusions (12 v 29; P = .017) and days of antibiotic therapy (28 v 40; P = .012) were significantly less for patients whose marrow was exposed to amifostine + 4-HC, compared with 4-HC alone. Unpurged backup marrow fractions were infused into three patients whose marrow was purged with 4-HC alone, because of inadequate marrow recovery. None of the patients who received amifostine + 4-HC-purged marrow required a backup marrow fraction. Complete remissions were achieved in 83% of patients with measurable disease, with no difference between the two cohorts. Forty- three percent of patients remained alive and progression-free at a mean of 13 months posttransplant. There was no significant difference in the rate or pattern of relapse for patients whose marrow was purged with amifostine + 4-HC compared with those whose marrow was purged with 4-HC alone. Ex vivo treatment of marrow with amifostine significantly shortens the time to marrow recovery, thereby reducing the risk of myelosuppressive complications in breast cancer patients receiving high- dose chemotherapy and 4-HC-purged ABMS. Since supportive care requirements are also significantly decreased, amifostine may reduce the cost of such therapy.  相似文献   
103.
A combined experience of 37 cases of subacute hepatic failure encountered in five major gastroenterology centres over a period of ten years is discussed. Majority (65%) were males with average age of 38 years. Maximum (54%) were in 5th decade. Jaundice (100%), abdominal distention (38.7%), swelling feet (64%), fever (54%), abdominal pain (54%), exhaustion (78.3%) were the major presenting features. Jaundice and ascites were present in all cases. Pedal oedema (78.3%), hepatomegaly (54%), splenomegaly (32.4%) and encephalopathy (27%) were the other important clinical features. Hypoalbuminemia and prolonged prothrombin time were significant laboratory findings in addition to hyperbilirubinemia and elevated ALT and AST. Hbs Ag was detected in 46%. Major complications encountered were renal failure (48.7%), spontaneous bacterial peritonitis (43.2%), other infections (43.2%), encephalopathy (43.2%) and upper gastrointestinal bleed (22%). 54% died during stay in hospital. To conclude subacute hepatic failure is potentially fatal condition.KEY WORDS: Subacute hepatic failure, HBsAg, Jaundice  相似文献   
104.
Fas分子与肝细胞凋亡   总被引:7,自引:4,他引:3  
近年来细胞分子生物学领域中的两个重要进展,即细胞凋亡概念的提出和Fas分子的分离与鉴定对肝病的研究有重要影响,加深了人们对肝细胞损伤与死亡的认识.1993年Ogasawaraetal[1]进行的Fas单抗毒性实验证实了Fas分子系统在肝细胞凋亡或损伤...  相似文献   
105.
106.
肠杆菌科细菌对碳青霉烯类抗生素的耐药性可以由过量产生AmpC酶且同时外膜孔道蛋白大量缺失和(或)外排泵过量表达,或产生能水解碳青霉烯类的β内酰胺酶引起。这些碳青霉烯酶可以分为金属β内酰胺酶(MSL)和丝氨酸碳青霉烯酶两类。替加环素是一类半合成的甘氨酰环素类抗菌药物,对其他类抗生素耐药的细菌通常对替加环素无交叉耐药。  相似文献   
107.
目的:测量国人全膝关节假体置换术胫骨近端截骨面后缘至腘窝血管之间的距离,以期为临床全膝关节置换术中避免损伤腘窝血管提供参考数据。方法:选择2006-06/12于解放军第二军医大学长征医院体检的50名正常成人(53膝),男29名(31膝),女21名(22膝)。所有观察对象均知情同意,且得到医院伦理道德委员会批准。对所有膝关节进行MRI扫描,在胫骨外侧平台以下10mm水平横断面上辨认腘动静脉,并测量胫骨近端截骨面后缘至腘窝动静脉的距离。结果:53膝全部进入结果分析,无脱落。①男性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.7±2.5,7.3±2.3)mm,95%可信区间分别为5.8~7.6mm,6.5~8.1mm。②女性胫骨近端截骨面后缘至腘动脉、腘静脉平均距离为(6.6±1.9,7.1±2.7)mm,95%可信区间分别为:5.8~7.4mm,5.9~8.3mm。③不同性别观察对象胫骨近端截骨面后缘至腘血管的距离差异无显著性意义(P>0.05)。结论:腘窝血管紧邻全膝关节假体置换术胫骨近端截骨面后缘,不同性别间无明显差异。全膝关节假体置换术中进行胫骨近端截骨,特别是后方操作时需特别谨慎,以避免损伤腘窝血管。  相似文献   
108.
目的:分析假体的选择与手术操作技术对非肿瘤性肩关节损伤人工肩关节置换术治疗的影响。方法:选择2001-04/2006-10在上海长征医院、西藏军区总医院、扬州第一人民医院等进行肩关节置换术患者33例。肱骨急性近端粉碎性骨折28例:行单极人工肩关节置换术17例,双极人工肩关节置换术1例,全肩关节置换术3例。肱骨头缺血坏死2例、骨性关节炎3例,均行全肩关节置换术。术后9个月时22例患者参加随访,18个月时17例参加随访,30个月时5例参加随访。结果:33例患者均进入结果分析。①1例肱骨假体留置过长致肩关节上举运动痛、静止不痛,翻修术后缓解。其余32例完全不疼。②术后患者上举85°~130°,平均(98.7±6.0)°,外旋17°~36°,平均(30.0±5.7)°。内旋75°~101°,平均(82.5±4.8)°。③患者假体置位较好,除1例肱骨假体未完全插入髓腔,翻修后正常。④材料与组织的生物相容性能:符合美国FDA及欧洲CE标准。结论:针对患者的具体情况选用合适的人工肩关节假体,术中假体固定方法的选择以及术后外固定材料的佩戴对肩袖功能有重要影响。  相似文献   
109.
从兔股骨头中提取总RNA的方法特点   总被引:2,自引:1,他引:2  
目的:建立一种高效、快速的骨组织总RNA提取方法。方法:实验于2005-01/2006-01在昆明医学院实验动物中心和中国科学院昆明动物研究所中科院细胞与分子进化重点实验室完成。取健康新西兰大白兔1只,截取其股骨头,迅速置于液氮罐中保存,于研钵中研磨,使骨组织始终保存于液氮中,继续研磨,如此重复3次,然后利用Trizol使骨细胞结构迅速破坏,将粉末转入离心管,室温静置5min。随后加入氯仿等有机溶剂处理、离心,使RNA与细胞DNA、蛋白质及其他成分分离从而得到总RNA。最后鉴定RNA的质量、纯度及产率,取2μL提取出的RNA在体积分数为0.008的甲醛变性琼脂糖凝胶上进行电泳,主要观察RNA的28S、18S及5S三个条带是否清晰,有无降解和DNA污染。以99μLDEPC水稀释1μLRNA样品,紫外分光光度计测量其吸光度(A)值,A260/A280之比值表示RNA的纯度,同时根据吸光度值计算其质量浓度。结果:①对提取的兔股骨头RNA进行琼脂糖凝胶电泳,可显示清晰的28S、18S两个条带,5S条带亦可见,表明了RNA是完整的。②用紫外分光光度法测定兔股骨头中提取出的RNAA260/A280,结果表明由本法提取的RNA纯度高,无DNA和蛋白质的污染。③经紫外分光光度计吸收定量,每毫克兔股骨头组织能提取1.0~1.2μg的总RNA。结论:本法提取骨组织总RNA方便、快捷,质量高,可用于骨组织的分子生物学研究。  相似文献   
110.
目的:对不同个体椎骨短期精度进行观察,发现骨质疏松的严重程度不同其短期精度不同。分析DPX-MD双能X射线骨密度仪测量不同个体椎骨骨面积、骨矿含量、椎体宽、椎体高的短期精密度,了解上述指标对骨矿含量或骨密度测定的影响,以便为骨矿含量或骨密度检测质量控制和减少误差提供依据。 方法:实验于2004-05/2006-12在川北医学院人体解剖实验室与川北医学院附属医院内分泌科骨密度室完成。①对象:铝体模;3个活体椎体(38岁骨密度正常男性;40岁骨质疏松症男性;62岁轻微骨量减少女性);1个带软组织的死体椎体(由川北医学院人体解剖实验室提供)。②方法及评估:采用美国Lunar公司生产的DPX-MD双能X射线骨密度仪测量各椎体的椎骨面积、骨矿含量、椎体宽、椎体高及骨矿含量/椎体宽。3次/d,连续测定5d。铝体模和死体椎体两端均用小木块固定在6.5cm的高度,放在15cm的水浴中,为减少误差由一人操作。由不同椎骨面积、骨矿含量、椎体宽、椎体高及骨矿含量/椎体宽可得到各自的变异系数。 结果:①腰椎各椎体和L2~4的骨矿含量的变异系数:各椎体或L2~4骨矿含量变异系数从正常男性椎体、骨质疏松症男性椎体、轻微骨量减少女性椎体与死体椎体呈依次增大。②各椎体和L2~4的椎骨面积、椎体宽、椎体高的变异系数:椎骨面积、椎体宽的值从铝体模、正常男性椎体、骨质疏松症男性椎体、轻微骨量减少女性椎体与死体椎体呈依次增大,尤其是轻微骨量减少女性椎体与死体椎体较大;椎体高的变异系数以骨质疏松症男性椎体与轻微骨量减少女性椎体较大,尤其是轻微骨量减少女性椎体的变异系数最大。 结论:不同个体椎骨骨面积、骨矿含量、椎体宽、椎体高的精度不同,对骨密度测定的影响不同。椎间隙欠清楚者由于椎体分椎线难于确定,椎体高度的测定对骨密度测定影响较椎间隙清楚者大;有骨质增生和骨质疏松越严重者由于椎体边缘线难于确定,椎体宽度的测定对骨密度测定影响较无骨质增生和骨密度正常者大;有骨质增生存在和骨质疏松越严重,骨面积的测定对骨密度测定影响越大;骨质疏松越严重,骨矿含量测定对骨密度测定影响越大。  相似文献   
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