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21.
125~I-后标记法是庄志雄等人(1994)提出的一种检测DNA-蛋白质交联物(DPCs)的新技术,该法在检测离体CHO细胞DPCs的实验中已显示出敏感、快速和简便的优点。本研究表明,125~I-后标记法不仅能有效地检出由紫外光和铬酸钾诱导的CHL细胞DPCs,并能有效而敏感地检测由铬酸钾和氯化镍引起的大鼠不同组织特别是白细胞DPCs形成的情况,是一种敏感的和可考虑应用于人群调查的DPCs检测方法。  相似文献   
22.
Iodine-125 interstitial irradiation for cerebral gliomas   总被引:3,自引:0,他引:3  
  相似文献   
23.
125I粒子组织间种植对人胃癌裸鼠移植瘤的杀伤作用   总被引:8,自引:3,他引:5  
目的 观察不同剂量^125I粒子对人胃癌裸鼠移植瘤的杀伤作用及组织损伤。方法 建立人胃癌BGC-823细胞裸鼠皮下移植瘤模型,随机分为对照组和实验组,将不同剂量(100、120、140Gy)地^125I粒子植于实验组。30、60d:比较移植瘤抑瘤率,病理组织学、局部皮肤反应、裸鼠体重及白细胞计数。结果30d,100、120、140Gy组抑瘤率分别为51.93%、79.18%、90.22%,病理组织学反应程度多为RCRG2(45.83%),各实验组组间除120Gy与140Gy(P〉O.05)组外,及分别与对照组比较,差异有统计学意义(P〈0.05);局部皮肤反应各实验组与对照组比较,差异有统计学意义(P〈0.05),各实验组组间差异无统计学意义(P〉0.05)。60d,各组抑瘤率分别为97.97%、100%、96.69%,病理组织学反应程度以RCRG1居多(62.5%),与对照组比较,差异均有统计学意义(P〈0.05),各实验组组间差异无统计学意义(P〉0.05);局部皮肤反应随剂量增高而加重,各实验组组间及其分别与对照组比较,差异有统计学意义(P〈0.05)。结论 不同剂量的^125I粒子在不同时间对人胃癌裸鼠皮下移植瘤有显著杀伤作用,但120Gy和140Gy组随剂量累积,损伤明显增加。提示100Gy可能是治疗人胃癌裸鼠皮下移植瘤的有效剂量。  相似文献   
24.
Abstract.   Jaaback KS, Ludeman L, Clayton NL, Hirschowitz L. Primary peritoneal carcinoma in a UK cancer center: comparison with advanced ovarian carcinoma over a 5-year period. Int J Gynecol Cancer 2006; 16(Suppl. 1): 123–128.
The relative incidence of primary peritoneal carcinoma (PPCa) and advanced (FIGO stage III or IV) ovarian serous carcinoma (AOSCa) was assessed over 5 years at a UK cancer center, and the sociodemographic, clinical, and survival data were compared. There were 23 women with PPCa and 55 with AOSCa. The ratio of PPCa:AOSCa was higher than previously reported. No statistical difference was found between the two groups with regard to age (mean 64.43 vs 64.07 years, P = 0.9), parity (1.6 vs 1.8, P = 1.0), personal/family history of another malignancy (although five patients with AOSCa but none with PPCa had personal histories of breast cancer), or serum CA125, CA19.9, and carcinoembryonic antigen (CEA) levels. Similar numbers in both groups had malignant ascites, although 5.8% of patients with AOSCa but none with PPCa had negative cytology. Tumor grade, stage, treatment, and survival were similar (median 586 vs 641 days, P = 0.66). This analysis of the largest published UK series of patients with PPCa does not support previous reports that patients with PPCa are older than those with AOSCa and have a worse prognosis; it suggests that both groups have similar sociodemographic characteristics, clinical profiles, and survival.  相似文献   
25.
26.
目的:研究不同剂量的放射性125I粒子对家兔尿道的放射性损伤。方法:麻醉下将放射性125I粒子植入雄性家兔尿道旁1.0cm处。125I粒子的放射性粒子活度分别为14.8MBq(A组)、29.6MBq(B组)和44.4MBq(C组),对照组(D组)仅尿道旁种植相当于粒子大小无放射性的无菌铅管1粒。植入后4周,摄尿道片,观察粒子位置等情况;原手术切口切开,取放射粒子周围2.0cm范围内的家兔尿道组织作肉眼、光学显微镜和电子显微镜观察,进行放射性损伤的评价。结果:术后4周,肉眼及光学显微镜观察,实验组与对照组粒子周围的尿道粘膜、粘膜下及肌层所见基本一致;C组少部分电镜视野中观察到尿道上皮胞质出现较多空泡变性、空化、嵴稀疏等超微结构的损伤。光镜下尿道入射性损伤评分,A、B、C、D组分别为(2.20±0.18)、(2.23±0.15)、(2.27±0.10)、(2.10±0.17)分,A、B、C组与D组相比,差异无显著性(P>0.05)。对线粒体作FlaMeng半定量分析,A、B、C、D各组评分分别为(1.23±0.13)、(1.34±0.25)、(1.41±0.30)、(1.12±0.13)分,A、B、C各组与D组(对照组)相比,差异无显著性(P>0.05)。结论:放射性125I粒子对尿道放射性损伤随粒子的放射性活度的增加而逐渐加重,呈明显的放射性活度效应关系;正常剂量的放射性粒子对尿道的损伤是很轻微的,是安全可行的。  相似文献   
27.
联合测定子宫内膜异位症患者血清中EMAb及CA125的临床评价   总被引:6,自引:0,他引:6  
目的:对联合测定子宫内膜异位症(内异症)患者血清中EMAb及CA125进行临床评价。方法:采取内异症109例术前(内异症组)和健康妇女30例(对照组)空腹静脉血,用酶联免疫吸附法(ELISA)测定两组血清中EMAb水平;用放射免疫法(RIA)测定血清中CA125水平。结果:内异症组EMAb阳性率为63.30%,对照组为10%,两组差异有显著性(P<0.05)。内异症各期及子宫腺肌病间EMAb阳性率差异无显著性(P>0.05)。内异症组血清CA125水平平均为70.70±16.62U/ml,对照组为15.38±5.32U/ml,两组差异有显著性。如以CA125≥35U/ml为阳性界值,则内异症组阳性率为80.23%,对照组为6.66%。单独测定EMAb诊断内异症的敏感性为63.30%,特异性为90%;单独测定CA125诊断内异症的敏感性为80.23%、特异性为93.33%。如以两者均阳性为诊断标准,则敏感性为57.80%,特异性为100%;如以其中之一阳性为诊断标准,则敏感性为91.74%,特异性为83.33%。结论:测定内异症患者血清中EMAb及CA125水平对内异症有较好的辅助诊断价值,联合测定EMAb及?  相似文献   
28.
Binding of a specific dopamine D1 receptor antagonist,125I-SCH 23982, was measured in rat brain sections by quantitative autoradiography at various time intervals, following a knife cut through the striatonigral pathway. Twenty-four hours after lesioning, accumulations of D1 receptor binding sites were found in sagittal sections both rostral and caudal to the lesion site. No other regions studied (caudate-putamen, nucleus accumbens, olfactory tubercle, and substantia nigra pars reticulata) showed any change in D1 receptor binding 24h after the lesion. In brain sections obtained 10 days after lesioning, only the substantia nigra pars reticulata had a significant decrease in D1 receptors ipsilateral to the lesion. These findings suggest the possibility of a presence of bidirectional axonal transport of D1 receptors in rat striatonigral pathway.  相似文献   
29.
The binding of radiolabelled lipoproteins, iodine-123-labelled low-density. lipoprotein (LDL) and indium-111-labelled LDL, to peripheral blood mononuclear cells (MNCs) was compared in normolipaemic subjects and in patients with heterozygous familial hypercholesterolaemia (FH). 123I-LDL and 111In-LDL binding to MNCs exhibited high-affinity, highly specific, time- and temperature-dependent binding reaching saturation at concentrations above 50 nM. The number of LDL binding sites (Bmax) was significantly (P<0.01) lower in FH patients (P<0.001; 123I-LDL: Bmax 279±44 ng protein/108MNCs; 111In-LDL: Bmax 309±43 ng protein/108MNCs) as compared with controls (123I-LDL: Bmax 2874±246 ng protein/108 MNCs; 111In-LDL: Bmax 3145±339 ng protein/108 MNCs). The corresponding dissociation constants (K d) were 16±8 nM for 123I-LDL and 12±6 nM for 123In-LDL in healthy volunteers (123In-LDL vs 111In-LDL, P<0.05). In FH patients, the K d values were 20±8 nM for 123I-LDL and 16±6 nM for 123In-LDL (P<0.05 vs controls for both 123I-LDL and 111In-LDL). 111In-LDL binding to MNCs was inhibited (IC50) by 30±8 nM in healthy controls and 38±12 nM in FH patients (P<0.05). 123In-LDL binding to MNCs was inhibited (IC50) by 34±8 nM in healthy controls and 46±10 nM in FH patients (P<0.05). Taken together, these results suggest a reduced number of LDL receptors expressed on MNCs from FH patients. We conclude that 111In-LDL and 123I-LDL are equally well suited as a probe of receptor-mediated binding and uptake of LDL.  相似文献   
30.
In a prospective study, the concentrations of CA 125, 17 beta-oestradiol and progesterone were assayed in 52 consecutive ovarian cysts, laparoscopically suspected to be endometriomas. Cysts with dark brown 'chocolate' fluid (n = 42) were excised by CO2-laser endoscopy. Cysts with clear fluid were diagnosed by pathology as follicular cysts (n = 5) or pseudoperitoneal cysts (n = 5). Fluids (n = 53) aspirated during echo-guided puncture for in-vitro fertilization (IVF) were assayed simultaneously. Of the 42 women undergoing a cystectomy, the clinical diagnosis of an endometrioma was confirmed by pathology in only 68%, the other cases being corpora lutea (27%) or follicular cysts (5%). Cyst fluids from corpora lutea had lower CA 125 concentrations (< 1000 IU/ml) together with high 17 beta-oestradiol concentrations (> 2000 pg/ml) and/or high progesterone concentrations (> 100 ng/ml). Endometriotic cysts had either very high CA 125 concentrations (> 10,000 IU/ml) as occurred in 78% or lower CA 125 concentrations (< 1000 IU/ml) together with low 17 beta-oestradiol and/or progesterone concentrations. 'Chocolate' fluid-containing cysts aspirated during IVF had similar concentration profiles of CA 125, 17 beta-oestradiol and progesterone and the diagnoses derived from these concentrations were not contradicted in 19/27 women undergoing a laparoscopy within 4 months. In eight women, however, with high CA 125 concentrations in their cyst fluid, no endometriotic cysts were found at laparoscopy. Only 68% of cysts containing 'chocolate' material were endometriotic cysts and CA 125 could be useful in making this diagnosis. This method is recommended when dark brown fluid is aspirated in IVF.  相似文献   
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