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41.
rhTPO 对60Co 照射小鼠造血系统影响的研究   总被引:1,自引:0,他引:1       下载免费PDF全文
目的为了检测TPO的体内活性及其对血小板减少的治疗作用,寻找用以治疗辐射及化学药物等所致骨髓损伤造成的血小板减少与缺乏,缓解临床上的出血症状,降低死亡率的一种新途径。方法本实验应用基因工程的方法重组了人的TPO,取昆明种正常雄性,经一次5.0Gy60Coγ射线全身照射小白鼠为动物模型,通过对外周血血象的观察,及小鼠骨髓造血祖细胞培养的检测,研究了rhTPO在体内对60Co全身照射处理小鼠的造血系统的影响。结果实验表明,rhTPO能够减轻照射对小鼠外周血血小板及骨髓造血祖细胞中巨核系祖细胞的影响,并有促进其早期恢复的作用,且这种作用是量效相关的。结论提示,TPO是巨核细胞系统较特异的正调控因子,具有促进巨核细胞增殖发育和刺激血小板生成的作用,是临床治疗骨髓组织损伤引起的血小板减少和缺乏及贫血的有希望的生物治疗药物。  相似文献   
42.
Pregnant mice were exposed to one of five regimens at 9.5 days of gestation: no treatment (group 1), intraperitoneal injection of normal saline (group 2), intraperitoneal injection of gadopentetate dimeglumine (group 3), intraperitoneal injection of gadopentetate dimeglumine and magnetic resonance (MR) exposure (group 4), and MR exposure alone (group 5). At 18 days of gestation, the mice were sacrifice and fetuses were removed and examined for the following end points: litter size, number alive or dead, fetal weight, extremity morphology, eye and ear development, and appearance of the head. A total of 739 fetuses were analyzed: group 1 (n = 161), group 2 (n = 149), group 3 (n = 142), group 4 (n = 136), and group 5 (n = 151). The only statistically significant difference was a lower mean fetal weight in the saline-injection group compared with the control group. The results show that MR exposure with and without gadopentetate dimeglumine had no adverse effect on the end points analyzed.  相似文献   
43.
CD44 is the principal cell surface receptor for hyaluronate. Variant forms of the receptor, produced by alternative splicing, have been found to be associated with tumor progression in a variety of cancers. Based on investigations at the RNA level, it has recently been proposed that expression of CD44 variant V2 was present in urothelial cancer but not in normal urothelium. Since a distinctive marker for urothelial cancer would be extremely useful, frozen sections of normal urothelium and urothelial cancer were examined for expression of standard CD44 and CD44V2. Frozen sections of specimens of 35 patients with transitional cell carcinoma of the bladder, 16 specimens of normal bladder and 5 ureters were examined. Immunohistochemical staining was performed using a polyclonal antibody to CD44V2 (PAB CD44V2), a monoclonal antibody to CD44V2 (MAB CD44V2) and a monoclonal antibody to CD44S (MAB CD44S). CD44V2 and CD44S were also measured in lysates of urine sediments from 21 patients by enzyme-linked immunoabsorbent assay (ELISA). All investigated transitional cell carcinomas expressed CD44V2. There was no differentiation between invasive and noninvasive carcinoma. CD44V2 was also expressed in normal urothelium. Standard CD44 was expressed by the transitional cell carcinoma, normal urothelium, musculature and interstitial tissue. The amount of CD44V2 and CD44S in lysates of urine sediments is not correlated to diagnosis. In contrast to investigations at the RNA level, CD44V2 on the protein level seems not to be a distinctive marker for urothelial cancer. Therefore, CD44V2 will not be a useful diagnostic marker for detection of transitional cell carcinoma.  相似文献   
44.
In a previous study, we used a murine monoclonal antibody, A7, against human colon carcinoma as a drug-carrier to treat colorectal cancer.1 In the present study, we found that MAb A7 also reacted immunohistochemically with 73% of human pancreatic carcinoma cell lines, with the A7 antigen mainly being detected on the cell surface. However, the A7 antigen was found in only 9% of the spent media of these human pancreatic carcinoma cell lines by ELISA. On the other hand, the positive incidence of CA19-9, POA, ferritin, CEA, DU-PAN-2 and SLX in those spent media was 100%, 64%, 64%, 55%, 55% and 36%, respectively. These results suggest that the A7 antigen may only rarely be shed into the sera of pancreatic cancer patients, in which case MAb A7 could be a suitable drug-carrier in targeting chemotherapy for pancreatic cancer patients.  相似文献   
45.
Toluene in blood as a marker of choice for low-level exposure to toluene   总被引:1,自引:1,他引:0  
The validity of two new biological exposure markers of toluene in blood (TOL-B) and toluene in urine (TOL-U) was examined in comparison with that of the traditional marker of hippuric acid in urine (HA-U) in 294 male workers exposed to toluene in workroom air (TOL-A), mostly at low levels. The exposure was such that the geometric mean for toluene was 2.3 ppm with a maximum of 132 ppm; the workers were also exposed to other solvents such as hexane, ethyl acetate, styrene, and methanol, but at lower levels. The chance of cutaneous absorption was remote. Higher correlation with TOL-A and better sensitivity in separating the exposed workers from the nonexposed subjects were taken as selection criteria. When workers exposed to TOL-A at lower concentrations (< 50 ppm, < 10 ppm, < 2 ppm, etc.) were selected and correlation with TOL-A was examined, TOL-B showed the largest correlation coefficient which was significant even at TOL-A of < 1 ppm, whereas correlation of HA-U was no longer significant when TOL-A was < 10 ppm. TOL-U was between the two extremes. The sensitivities of TOL-B and TOL-U were comparable; HA-U showed the lowest sensitivity. Thus, it was concluded that TOL-B is the indicator of choice for detecting toluene exposure at low levels.  相似文献   
46.
Summary Twenty-two persons (20 men and 2 women) were examined for their external and internal exposure to the glycol ether 1-methoxypropan-2-ol (PGME) during the production, leak testing and mounting of brake-hoses. For the measurement of external exposure, personal air monitoring was the method of choice. Average concentrations of PGME of 82.2 mg/m3 (22.3 ppm), 68.6 mg/m3 (18.6 ppm) and 11.3 mg/m3 (3.1 ppm) were found in the air of the brakehose production, leak test and mounting areas, respectively. For the estimation of internal exposure to PGME, this glycol ether was measured in both urine and blood. The biological samples were taken post-shift. The highest internal exposure levels were found in the brakehose production section and in the leak test area. The average post-shift concentrations for PGME in workers in the brakehose production section were 4.6 mg/l in urine and 13.5 mg/l in blood; the corresponding figures for workers in the leak test area were 4.2 mg/l in urine and 11.0 mg/l in blood. In blood and urine samples of workers engaged in the mounting area, PGME levels were below the detection limits. The elimination kinetics of PGME were also studied in three highly exposed persons, and mean excretion half-lives of PGME of approximately 4.4 h were found. On the basis of our results we made a rough calculation of a future biological tolerance value: we would except that concentrations of 38-109 mg per litre of blood and 10–31 mg per litre of urine would correspond to the German MAK value for PGME (375 mg/m3).  相似文献   
47.
Multiple tests were done on the ejaculates of 10 asthenozoospermic patients and nine healthy normozoospermic volunteers in an attempt to identify individually the cause of low sperm motility in these patients. Possible defects in the sperm plasma membrane and the motility apparatus of sperm, and in epididymal function affecting the development of motility, were investigated. The presence of seminal sperm antibodies or any motility-inhibiting factors in the seminal plasma that could be removed by washing were also tested. Each test was positive in only one or two patients but axonemal dysfunction was identified in nine patients. Removal of seminal plasma from asthenozoospermic samples did not improve sperm motility to any greater extent than with donor ejaculates, and the motile sperm of these patients exhibited characteristics mostly similar to those of donors under various incubation conditions. Selection procedures are, therefore, required to obtain samples of good quality sperm from such asthenozoospermic ejaculates.  相似文献   
48.
刘贤铭 《药学进展》2003,27(6):365-368
[目的]了解肿瘤用药的消费现状及发展趋势,为临床合理用药提供依据。[方法]对本院1996年-2002年抗肿瘤药、生物反应调节剂和升白细胞药的用药情况进行统计分析,以药品的年消耗金额作统计。[结果]抗肿瘤药、生物反应调节剂和升白细胞药分别占全部药品年消耗总金额的24.24%~33.73%、15.80%~23.33%和5.86%~9.11%。[结论]抗肿瘤药、生物反应调节剂和升白细胞药是用于肿瘤治疗的主要药品,尤其是抗肿瘤天然药物有着广阔的应用前景。  相似文献   
49.
目的观察部分创面外用抗菌药物与成纤维细胞生长因子(FGF)2、表皮生长因子 (EGF)、重组人生长激素(rhGH)对成纤维细胞生物学特性的影响。方法体外培养成纤维细胞, 按所加药物不同分为对照组(常规培养)、丁胺卡那霉素(0.021、0.210、2.100 mg/L)组、庆大霉素(5、 50、500 mg/L)组、氯霉素(0.01、0.10、1.00 mg/L)组、磺胺米隆(5、10 g/L)组、FGF2(2 400 U/ml)组、 EGF(2 000 U/ml)组及rhGH(0.016、0.160、1.600 g/L)组。用噻唑蓝(MTT)法测定各组成纤维细胞增殖活性[吸光度(A)值],用流式细胞仪检测细胞周期,并于显微镜下观察细胞形态的变化。结果 (1)MTT法检测:与对照组A值0.455 3±0.021 7比较,各种剂量丁胺卡那霉素组、庆大霉素组、氯霉素组、磺胺米隆组成纤维细胞A值均明显降低(P<0.05或0.01),其中磺胺米隆(5、10 g/L)组降低最明显,分别为0.101 3±0.001 1、0.095 0±0.004 1(P<0.01)。FGF2组及0.016 g/L rhGH 组细胞A值明显高于对照组(P<0.05),而EGF组及0.160、1.600 g/L rhGH组A值与对照组接近 (P>0.05)。(2)细胞周期检测:对照组细胞增殖指数(PI)为(9.63±0.45)%,与之比较,0.210 mg/L丁胺卡那霉素组细胞PI值无明显变化(P>0.05),FGF2组、EGF组及0.016 g/L rhGH组PI值均明显升高,分别为(46.76±2.33)%、(42.30±1.41)%、(13.29±0.47)%(P<0.05或0.01)。 (3)形态学观察:对照组、EGF组及0.160、1.600 g/L rhGH组成纤维细胞数目较多,呈长条形或梭形, 轮廓不清,透明度高;丁胺卡那霉素组、庆大霉素组、氯霉素组、磺胺米隆组细胞数目较少,形态不规则,轮廓清晰,透明度低,细胞内多有颗粒样物质及空泡;FGF2组、0.016 g/L rhGH组细胞分布均匀、密集,呈长条形或梭形,核分裂相多见,轮廓不清,透明度高。结论不同创面外用药物对成纤维细胞生物学特性的影响各异,在创面修复过程中应选择合适的创面外用药物,以促进愈合并抑制瘢痕增生。  相似文献   
50.
Our previous study demonstrated that pro-gastrin-releasing peptide(31–98), or ProGRP, is a specific tumor marker in patients with small cell lung carcinoma (SCLC). Using a newly developed, highly sensitive enzyme-linked immunosorbent assay (ELISA) for ProGRP, we analyzed 1,446 samples including those obtained from 478 lung cancer patients to evaluate the clinical usefulness of this ELISA. Several properties indicated that ProGRP is a useful tumor marker for SCLC. First, ProGRP was specifically elevated in SCLC patients. In non-SCLC patients and patients with non-tumorous lung diseases, its serum level was very rarely elevated. Secondly, ProGRP was a reliable marker, in terms of the marked elevation of serum ProGRP levels in SCLC patients. Thirdly, serum ProGRP levels were elevated in SCLC patients even at a relatively early stage of this disease. Fourthly, changes in the serum ProGRP level showed an excellent correlation with the therapeutic responses in SCLC patients. Neuron-specific enolase (NSE) is accepted as a tumor marker of SCLC patients. With the aim of comparing ProGRP and NSE as tumor markers for SCLC patients, we measured serum NSE levels in all samples collected in the present study. We found that ProGRP was superior to NSE in terms of sensitivity, specificity and reliability. Therefore, we consider that ProGRP can play a major role as a clinical tumor marker for SCLC patients.  相似文献   
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