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61.
Summary In order to investigate further the possible relationship between urinary stone formation and marathon running, the crystalluria in seven male, stone forming runners was characterized. Particle size distribution curves (Coulter counter) and crystal number, size and morphology (scanning electron microscopy) were measured. These studies suggest that urinary stone formation may be accelerated in those subjects with previous histories of renal stone formation but that the nature of the crystalluria is favourably affected by an increase in fluid intake. The presence of large quantities of mucoid material in the urine of natural stone formers and its absence in the urine of stone-forming runners is cited as evidence for the existence of different aetiological mechanisms in these groups. It is concluded that while natural stone formers may be at chronic risk of stone formation due to pathological factors, marathon runners may be at acute risk due to factors associated with long distance running itself.  相似文献   
62.
反相高效液相色谱法测定塞来昔布片含量   总被引:6,自引:0,他引:6  
目的 :建立反相高效液相色谱法测定塞来昔布片的含量。方法 :采用ZorbaxSB -C18色谱柱 ,以 0 .0 2mol·L-1磷酸二氢钾缓冲液 (pH5 .8) 乙腈 (4 5 :5 5 )为流动相 ,流速为 1.0mL·min-1,以 5 甲基 2 硝基苯酚为内标物 ,检测波长为 2 5 2nm。结果 :塞来昔布在 10 .2~ 5 0 .1mg·L-1范围内呈良好线性 (r =0 .9998) ,平均回收率为 99.8% ,RSD为 0 .35 %。结论 :本法可用于该片的含量测定 ,操作简便 ,结果准确。  相似文献   
63.
反义技术是近20年来发展的一种全新的药物设计方法。本文就近几年来反义寡核苷酸在化学修饰方面,包括骨架修饰、糖环修饰、碱基修饰等的最新发展进行了综述。  相似文献   
64.
65.
A minimally invasive model using a manual abrader to induce adhesions in the chicken's central digit is described. The flexor synovial sheath and the profundus tendon were abraded with access through small flaps at the level of the proximal and distal phalanges of the avian long toes. The birds were divided into two groups according to the severity of the induced trauma. Group I birds received an abrasion injury and were euthanized to allow biomechanical testing 5 weeks postoperatively. Group II birds had a more severe abrasion and were euthanized similarly and tested 5 weeks after surgery. Results were compared with nonsurgical controls. Long toe function was evaluated weekly by measuring (1) the range of active flexion of each interphalangeal joint, resolved to total angular range; (2) the grasping ability on graded-diameter perches; and (3) the flexion deficit of the long toe. Postmortem biomechanical properties of the adhesions were measured. There was a significant difference between the unoperated controls and abraded digits of both groups in all parameters (p < 0.001). There was, in addition, a marked change in most of the measured parameters between groups I and II. In group I digits the functional and biomechanical deficit was less than group II. In summary, this animal model of long-segment abrasive injury to the tendon and sheath is a simple and reproducible method to generate adhesions and can be used for the evaluation of treatment modalities for adhesion prevention.  相似文献   
66.
Objective To study the setup errors in three-dimensional conformal radiotherapy (3DCRT) for thoracic esophageal carcinoma using electronic portal imaging device(EPID) and calculate the margins from CTV to PTV. Methods Forty-one patients with thoracic esophageal carcinoma who received 3DCRT were continuously enrolled into this study. The anterior and lateral electronic portal images (EPI) were aquired by EPID once a week. The setup errors were obtained through comparing the difference between EPI and digitally reconstructed radiographs(DRR). Then the setup margins from CTV to PTV were calculat-ed. By using self paired design,22 patients received definitive radiotherapy with different margins. Group A: the margins were 10 mm in all the three axes;Group B: the margins were aquired in this study. The differ-ence were compared by Paired t-test or Wilcoxon signed-rank test. Results The margins from CTV to PTV in x,y and z axes were 8.72 mm, 10.50 mm and 5.62 mm, respectively. Between the group A and group B, the difference of the maximum dose of the spinal cord was significant(4638.7 cGy±1449.6 cGy vs. 4310.2 cGy±1528.7 cGy; t=5.48, P=0.000), and the difference of NTCP for the spinal cord was also significant (4.82%±5.99% vs. 3.64%±4.70%;Z=-2.70,P=0.007). Conclusions For patients with tho-racic esophageal carcinoma who receive 3DCRT in author's department,the margins from CTV to PTV in x, y and z axes were 8.72 mm, 10.50 mm and 5.62 mm, respectively. The spinal cord could be better protected by using these setup margins than using 10 mm in each axis.  相似文献   
67.
核素骶髂关节显像对强直性脊柱炎治疗监测的价值   总被引:2,自引:0,他引:2  
目的 利用核素骶髂关节显像以及骶髂关节与骶骨的核素比值测定方法,探讨其在强直性脊柱炎(AS)治疗监测中的价值。方法 29例临床及CT确诊AS的病人,共58个骶髂关节,先行核素骶髂关节显像及其核素比值测定,然后进行临床药物治疗。治疗后2周再行同样的核素检查方法,观察其变化情况。结果 58个骶髂关节中,有51个骶髂关节示放射性核素呈不同程度浓聚,骶髂关节与骶骨放射性比值明显高于正常;2周后的检查所见其中原有异常的骶髂关节情况明显改善,有51个骶髂关节与骶骨比值均有降低,其中47个降至正常范围。两组比较差异有显著意义。结论 核素骶髂关节显像及其骶髂关节与骶骨核素比值测定,对骶髂关节炎的活动性监测具有重要的应用价值。  相似文献   
68.
A prospective study of 48 women was carried out to estimate the incidence of common genital pathogens in women referred to colposcopy clinic requiring diathermy loop excision and to compare patient morbidity in the subgroups with and without genital pathogens. Of the 43 women included in the analysis, genital pathogens were present in 24 cases (56%) and absent in 19 (44%) of the 24 positive cases, 19 (79%) women had pathogen(s) on the cervical swab, 24 (100%) had pathogen(s) on the high vaginal swab and 15 (63%) had both a positive cervical and high vaginal swab (HVS). The most frequently isolated groups of organisms were mixed anaerobes, alone (four HVS and four cervical) or in combination with Gardnerella vaginalis (four HVS and three cervical) or coliforms (two HVS and two cervical). The mean duration of bleeding and vaginal discharge in the two study groups was not statistically significant (t value 1.97, P 0.05; and t value 0.48, P 0.5, respectively). However, the mean duration of bleeding graded by the patient as being moderate to severe was significantly different in the two groups (t value 3.18 P 0.01). Fifty-six per cent of the women in the study had confirmed genital pathogens, predominantly anaerobes, and the prolonged moderate-to-severe bleeding in this group suggests a potential role for prophylactic bacteriocides, although the study size was unable to implicate a single pathogen.  相似文献   
69.
目的:测定舒金克喘胶囊中和厚朴酚与厚朴酚的含量。方法:色谱条件:色谱条件与系统适用性实验:Hypersil ODS2 C18分析柱(150mm 4.6mm,5μm);流动相:甲醇:水=(78:22),检测波长294nm流速1.0ml/min,室温操作。理论塔板数按厚朴酚计算应不低于3000。结果:和厚朴酚与厚朴酚平均回收率分别为99.62%(RSD=1.34%),98.56%(RSD=1.49%)。结论:方法快速准确,样品处理简便易行。  相似文献   
70.
目的:探讨DPC4(deleted in pancreatic carcinoma locus4,DPC4)基因在非小细胞肺癌(NSCLC)中的表达及其与微血管形成的关系。方法:利用免疫组织化学S-P法检测52例NSCLC组织、19例相应的癌旁正常肺组织中DPC4、VEGF的表达,用CD34标记血管内皮细胞并计算微血管密度MVD值。结果:DPC4在肺癌原发灶中的阳性表达率为63.5%(33/52),与癌旁正常肺组织中的阳性表达率89.5%(17/19)相比,DPC4阳性表达水平显著降低(P〈0.05);DPC4与组织学类型、肿瘤细胞分化程度无关(P〉0.05),但与淋巴结转移显著相关(P〈0.05)。52例NSCLC中,DPC4的表达与VEGF、MVD值均呈负相关(r=-0.303,P=0.020)。结论:DPC4的低表达可能是肺癌发生过程的早期事件,可促进肺癌的淋巴结转移,并可通过直接或间接的作用促进肺癌血管生成。  相似文献   
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