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101.

Background  

Computer-assisted surgery (CAS) can act as an intraoperative ruler in high tibial osteotomy (HTO) to visualize continuously the leg during surgery.  相似文献   
102.
目的探讨吡柔比星(THP)与丝裂霉素C(MMC)对膀胱癌T24细胞株的抑制作用。方法将膀胱癌T24细胞株分为4组,分别给予THP、MMC、THP+MMC和MMC+THP。用MTT法测定T24细胞的增殖抑制率,用TuNEL法检测T24细胞的凋亡情况。结果THP、MMC、THP+MMC和MMC+THP四组的增殖抑制率(%)分别为54.3±6.4,48.9±7.2,62.3±5.9,69.1±6.2;凋亡指数(%)分别为6.2±2.5,4.4±2.7,6.7±3.0,7.4±3.2。联合用药组对T24细胞的抑制作用优于单药THP和MMC对肿瘤细胞的抑制作用(P〈0.05)。在联合用药组中,MMC+THP组对T24细胞的抑制作用优于THP+MMC组对肿瘤细胞的抑制作用(P〈O.05)。结论THP和MMC均可抑制膀胱癌T24细胞株的增殖并诱导凋亡,两药序贯联合用于膀胱灌注化疗可能具有合理性。  相似文献   
103.
A new specific and sensitive LC–MS–MS method for the detection of taxine B and isotaxine B, the main toxic pseudo-alkaloids from yew (Taxus sp.), in biological samples (blood, urine, gastric content) was developed. Biological samples were prepared for LC–MS–MS by means of solid-phase extraction (SPE) procedure and yielded a recovery of 86%. Chromatographic separation was achieved using an RP18 column. Detection of taxine B and isotaxine B was performed using multiple reaction monitoring with m/z 584.2 as precursor ion, i.e. [M+H]+, of both isomers and m/z 194.3 and m/z 107.1 as product ions after collision-induced dissociation. Docetaxel was applied as internal standard. The method was fully validated for the analysis of blood samples. Linearity was proven in the range from 0.1–500 ng/g. The limit of detection and the limit of quantitation are 0.4 and 2 ng/g, respectively. The method was applied to the determination of taxine B and isotaxine B in four fatal cases (two humans, two horses) with suspected yew intoxication. Blood levels were 105, 168, 174 and 212 ng/g.  相似文献   
104.
The intentional inhalation of a volatile substance (“sniffing”) causing euphoria and hallucinations is an under-recognised form of substance abuse in children and adolescents with a high morbidity and mortality. Sudden death can be caused by cardiac arrhythmia, asphyxia or trauma. Two fatal cases of isobutane sniffing of cigarette lighter refill containing isobutane are reported. Toxicological investigations revealed the presence of isobutane in the heart blood and brain tissue of both cases (case 1: heart blood 0.1 μg/g, brain tissue 2.3 μg/g; case 2: heart blood 4.6 μg/g, brain tissue 17.4 μg/g) and the presence of its metabolite 2-methyl-2-propanol in the heart blood of both cases (0.5 and 1.8 μg/g, respectively). The histological investigations of the inner organs showed similar results in both victims. Autopsy findings, results of the histological and immunohistochemical investigations, toxicological findings and analytical procedures are discussed.  相似文献   
105.
The 16 short tandem repeat systems D3S1358, VWA, FGA, TH01, TPOX, CSF1PO, D5S818, D13S317, D7S820, ACTBP2, D2S1338, D16S539, D19S433, D21S11, D18S51 and D8S1179 were amplified in a population sample composed of 333 immigrants from Afghanistan. The 16 loci met Hardy–Weinberg expectations and possess a combined matching probability of 1 in 3.6 × 1014 and a combined mean exclusion chance greater than 0.9996 in this Afghan population. Approximately 12,000 meiotic transfers were investigated and 19 mutations were observed in the repeat units of FGA (n=6), ACTBP2 (n=5), D3S1358 (n=2), D5S818 (n=2), D7S820 (n=2), VWA (n=1) and D8S1179 (n=1).Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   
106.
Porcine xenografts lacking swine leukocyte antigen (SLA) class I are thought to be protected from human T cell responses. We have previously shown that SLA class I deficiency can be achieved in pigs by CRISPR/Cas9‐mediated deletion of β2‐microglobulin (B2M). Here, we characterized another line of genetically modified pigs in which targeting of the B2M locus did not result in complete absence of B2M and SLA class I but rather in significantly reduced expression levels of both molecules. Residual SLA class I was functionally inert, because no proper differentiation of the CD8+ T cell subset was observed in B2Mlow pigs. Cells from B2Mlow pigs were less capable in triggering proliferation of human peripheral blood mononuclear cells in vitro, which was mainly due to the nonresponsiveness of CD8+ T cells. Nevertheless, cytotoxic effector cells developing from unaffected cell populations (eg, CD4+ T cells, natural killer cells) lysed targets from both SLA class I+ wildtype and SLA class Ilow pigs with similar efficiency. These data indicate that the absence of SLA class I is an effective approach to prevent the activation of human CD8+ T cells during the induction phase of an anti‐xenograft response. However, cytotoxic activity of cells during the effector phase cannot be controlled by this approach.  相似文献   
107.
咪唑立宾在肾移植术后的应用   总被引:4,自引:0,他引:4  
目的 探讨咪唑立宾(MZR)在肾移植术后的临床应用效果。方法 选取2003年8月至2004年4月间肾移植术后采用环孢素A(CsA)或他克莫司(FK506)+MZR+激素三联免疫抑制方案的患者112例,定期检查患者用药后的血常规、肝肾功能、尿酸、血糖、血脂等生化指标;对乙型肝炎病毒、丙型肝炎病毒、艾滋病病毒、巨细胞病毒、EB病毒、腺病毒及带状疱疹病毒进行抗原学或者抗体监测;疑有排斥反应时,行移植肾穿刺病理检查。统计病毒感染发生情况,评价该治疗方案的安全性。结果 肾移植术后随访12~20个月,患者的人/肾存活率均为96%;急性排斥发生率为11.6%,经冲击治疗后全部逆转;患者主要不良反应是高尿酸血症,但可以控制而不需要停药;巨细胞病毒感染率为11.6%,未发生巨细胞病毒病;有1例感染腺病毒。结论 MZR是一种安全有效的免疫抑制剂,病毒感染的发生率相对较低。由于肾移植术后应用MZR患者主要不良反应是高尿酸血症,因此要注意对患者的尿酸进行控制。  相似文献   
108.
以体外抑制肿瘤细胞增殖的活性作为筛选导向,从灰树花深层发酵培养菌丝体中提取、分离纯化得到一酸性糖酞GFPS1b.HPGPC法测得其重均相对分子质量为21000.蛋白质质量分数16.60%,糖质量分数为81.32%。利用化学方法(单糖组成分析、部分酸水解、甲基化分析)和仪器方法(GC、GC—MS、红外吸收光谱、核磁共振)分析GFPS1b的糖链结构,结果表明其单糖组成主要有G1c、Ga1、Ara和少量的糖醛酸,其糖链主链由两个α-D—G1c(1→3)、α-D—Ga1(1→4)、α-D—G1c(1→3,6)和α-D—Ga1(1→6)组成的,其中葡萄糖基的6位发生取代,取代侧链主要为α-L—Ara-(1—4)-α-D—Glc(1→。可以认为GFPS1b为一新糖肽。  相似文献   
109.
目的 比较和评价首次肾移植受者使用他克莫司缓释胶囊和他克莫司胶囊治疗的安全性和有效性.方法 11家中心的241例肾移植受者随机分配为试验组(应用他克莫司缓释胶囊+吗替麦考酚酯+皮质激素)和对照组(应用他克莫司胶囊+吗替麦考酚酯+皮质激素),观察时间从移植当天至术后12周.试验组受试者每天上午一次性服用他克莫司缓释胶囊,对照组受试者每天早晚分2次服用他克莫司胶囊.两组试验药物的起始剂量均为0.1~0.15 mg·kg-1·d-1.分别在治疗前和治疗后第1、3、7、14、28、56和84 d各随访1次.对两组受者用药的有效性、安全性、依从性以及不良反应进行对比分析.结果 进入符合方案分析集者共223例,其中试验组111例,对照组112例.两组受者的平均年龄、性别、原发病的差异均无统计学意义,各有12例发生急性排斥反应.对照组和试验组分别有36例(32.1%)和37例(33.3%)发生与试验药物相关的不良反应.无受者连续3 d未按照方案服用药物.两组治疗后期较治疗前期的服药量均减少,且组内差异有统计学意义(P<0.05).治疗早期两组血他克莫司浓度较接近,从28 d开始,试验组血药浓度低于对照组,但差异无统计学意义.结论 从药物安全性、药物治疗的有效性、相关不良反应以及受者依从性各方面分析显示,每天1次的他可莫司缓释胶囊均非劣效于每天2次的他克莫司胶囊,在临床应用中,用他克莫司缓释胶囊代替他克莫司胶囊是切实可行的.
Abstract:
Objective To compare the efficacy and safety of twice-daily tacrolimus (Tacrolimus BID; Prograf) vs once-daily prolonged release tacrolimus (Tacrolimus QD; Advagraf), combined with steroids and mycophenolate mofetil in preventing acute rejection in De Novo renal transplantation patients. Methods 241 patients from 11 centers were randomized into two groups with 3 months observation period post-transplantation. Advagraf was administered as a single oral dose in the morning (initially 0. 1-0. 15 mg/kg every day) and Prograf was administered in two equal oral doses 12h apart (initially 0. 1-0. 15 mg/kg). Study visits were scheduled for days 1, 3, 7, 14, 28, 56, 84post-transplantion. The efficacy, safety, compliance and adverse effects were compared between two groups. Results Totally 223 patients completed the study. The two groups were comparable in age,gender and primary disease. There were 12 episodes of acute rejection in each group. There was no graft loss or patient death in both groups. The incidence of drug related adverse events was 32. 1 %and 33. 3% respectively in the control and experimental groups. Dosage was decreased in both groups and there was significant difference in each group. The trough level was similar at the initiate period.Twenty-eight days post-transplantation the trough level in the Advagraf group was lower than in the Prograf group. Conclusion Advagraf has the same efficacy, safety and drug related adverse effects as Prograf. It is practical and feasible for Advagraf substitute for Prograf in clinical practice.  相似文献   
110.
目的 观察膀胱灌注吡柔比星(THP)/羟喜树碱(HCPT)预防浅表性膀胱癌术后复发和并发症的疗效.方法 62例浅表性膀胱癌术后患者,随机分为两组:Ⅰ组THP(32例),Ⅱ组HCPT(30例),所有病例分别于术后6 h(TURBT)和1周(膀胱部分切除术和TURBT合并膀胱穿孔者)开始规律膀胱灌注化疗,比较膀胱癌复发率、...  相似文献   
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