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71.
S D Qiu C Y Young D L Bilhartz J L Prescott G M Farrow W W He D J Tindall 《The Journal of urology》1990,144(6):1550-1556
Prostate-specific antigen (PSA) mRNA was detected by in situ hybridization utilizing a 428 base pair [35S]-labelled cDNA probe from the 3' noncoding region of the PSA gene. Thirty six fresh surgical specimens were collected from patients undergoing radical retropubic prostatectomy for carcinoma of the prostate. Quantitative analysis of the levels of PSA mRNA in both the benign and malignant tissues was performed using an IBAS 2000 Image Analysis System. The results of this study demonstrated that there is a significant decrease in the expression of PSA mRNA in the carcinoma tissue when compared to the benign epithelium. The average binding (number of silver grains/1 x 10(4) microns. 2) for 20 specimens of malignant epithelium was 475 +/- 161 and 586 +/- 140 for 16 specimens of benign epithelium (p less than 0.05). Eleven patients had both benign and malignant tissue from the same surgical specimen available for study. From these paired specimens, the PSA mRNA expression was also significantly reduced in the malignant epithelium when compared to the benign epithelium, 445 +/- 162 and 588 +/- 135 respectively (p less than 0.005). The PSA protein was detected using a monoclonal antibody to PSA with an immunohistochemical staining technique. The PSA protein expression paralleled the expression of the PSA mRNA in the majority of the tissue sections. Many of the tumor specimens showed a heterogeneous expression of PSA, whereas all of the benign epithelium had a uniform high level of PSA expression. In conclusion, PSA mRNA and protein are located only within the glandular epithelial tissue, the expression of PSA protein parallels that of the PSA mRNA, and both the PSA protein and PSA mRNA are significantly decreased in the malignant epithelium when compared to benign prostatic epithelium. 相似文献
72.
伽玛刀治疗垂体大腺瘤临床分析(附30例报告) 总被引:2,自引:0,他引:2
目的 研究伽玛刀治疗垂体大腺瘤的效果及影响疗效的因素。方法 30例垂体大腺瘤病人用1.0T磁共振定位,Gamma-plan计划系统规划,等剂量曲线45%~60%(平均49.7%),周边剂量12~35Gy(平均22.9Gy),中心剂量24~70Gy(平均45.4Gy).Leksell伽玛刀实施放射外科治疗。分析治疗后垂体大腺瘤病例,总结其疗效和影响疗效的因素。结果 随访12~60个月,平均28个月,肿瘤完全消失6例(20%),肿瘤缩小19例(63.3%),无变化5例(16.7%);19/20(95.5%)功能性垂体腺瘤内分泌症状改善,临床症状好转,1例过早绝经(年龄36岁);5/10(50%)无功能性垂体腺瘤体积缩小.症状改善。结论 伽玛刀对于垂体大腺瘤仍是一种有效的治疗方法,其疗神与腺瘤的举类型、体积、照射剂量、剂量体剂、MRI信号特征密切相姜。 相似文献
73.
目的:从分子流行病学的角度探讨广东省结核分支杆菌菌株流行的分布。方法:构建广东省74株临床分离的以RFLP为基础的结核分支杆菌的IS6110 DNA指纹图谱技术,确诊结核分支杆菌菌株的流行分布。结果:24.3%(18/74)的结核菌株的IS6110 DNA指纹相似值在1-0.65之间,鉴定结果为它们均是“北京家族”结核分支杆菌菌株。结论:广东省结核菌株流行主要存在着遗传关系接近,在基因水平上相关程度较高的“北京家族”结核分支杆菌菌株,且该家族菌株正以一定的比例在我省流行。 相似文献
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目的 探讨头皮针在新生儿卡介苗接种中的应用效果。方法将182例符合接种条件的新生儿随机分为观察组(102例)及对照组(80例)。观察组采用4.5号头皮针接种,对照组采用一次性1ml注射器(4.5号针头)注射。结果观察组接种效果显著优于对照组,注射时间显著短于时照组(均P〈0.01)。结论 头皮针应用于新生儿卡介苗注射可显著提高注射效果,缩短注射时间。 相似文献
76.
BACKGROUND: Under the normal circumstance, there exist some synapses with inactive functions in central nervous system (CNS), but these functions are activated following nerve injury. At the early stage of brain injury, the abnormal functions of brain are varied, and they have very strong plasticity and are corrected easily.
OBJECTIVE: To observe the changes of neuronal morphology in hippocampal CA1 region and memory function in newborn rats with hypoxic-ischemic encephalopathy(HIE) from ischemia 6 hours to adult.
DESIGN: Completely randomized grouping, controlled experiment.
SETTING: Taian Health Center for Women and Children; Taishan Medical College.
MATERIALS: Altogether 120 seven-day-old Wistar rats, of clean grade, were provided by the Experimental Animal Center, Shandong University of Traditional Chinese Medicine. Synaptophysin (SYN) polyclonal antibody was provided by Maixin Biological Company, Fuzhou.
METHODS: This experiment was carried out in the Laboratory of Morphology, Taishan Medical College between October 2000 and December 2003. ① The newborn rats were randomly divided into 2 groups: model group and control group, 60 rats in each group. Five rats were chosen from each group at postoperative 6 hours, 24 hours, 72 hours, 7 days, 2 weeks and 3 weeks separately for immunohistochemical staining. Fifteen newborn rats were chosen from each group at postoperative 4 weeks and 2 months separately for testing memory ability (After test, 5 rats from each group were sacrificed and used for immunohistochemical staining)② The right common carotid artery of newborn rats of model group was ligated under the anesthetized status. After two hours of incubation, the rats were placed for 2 hours in a container filled with nitrogen oxygen atmosphere containing 0.08 volume fraction of oxygen, thus, HIE models were created; As for the newborn rats in the control group, only blood vessels were isolated, and they were not ligated and hypoxia-treated. ③ Thalamencephal tissue sections of newborn rats of two groups were performed DAB developing and haematoxylin slight staining. Cells with normal nucleous in 250 μm-long granular layer which started from hippocampal CA1 region were counted with image analysis system under high-fold optical microscope (×600), and the thickness of granular layer was measured. The absorbance (A) of positive reactant of SYN in immunohistochemically-stained CA1 region was measured. Learning and memory ability were measured with step through test 3 times successively. ④ t test and paired t test were used for comparing intergroup and intragroup difference of measurement data respectively, and Chi-square for comparing the difference of enumeration data.
MAIN OUTCOME MEASURES: Comparison of cytological changes in hippocampal CA1 region and memory ability at different postoperative time points between two groups.
RESULTS: Totally 120 newborn rats were involved in the result analysis. ① Cell morphological changes in hippocampal CA1 region: In the control group, with aging, perikaryon, nucleus and nucleolus in cortex of parietal lobe were significantly increased, Nissl body was compacted, the amount of neurons was declined, but the A of SYN positive reactant was relatively increased. In the model group, at postoperative each time point, neurons were seriously shrunk and dark-stained, nucleus was contracted, chromatin was condensed, nucleolus was unclear, even cells disappeared, especially the cells in 6 hours and 24 hours groups. The amount of neurons with normal morphology in hippocampal CA1 region and granular layer thickness in the model group at postoperative each time point were significantly less or smaller than those in the control group at postoperative 6 hours respectively (t =3.002-1.254, P < 0.01). The A value of SYN positive reactant at postoperative 2, 3 and 4 weeks was significantly higher than that at previous time point (t =2.011-2.716,P < 0.05-0.01). ② Test results of learning and memory ability: In the first test, there was no significant difference in the ratio of rats which kept memory ability between two groups (P > 0.05); In the third test, the ratio of rats which kept memory ability in the model group was significantly lower than that in the control group at postoperative 4 weeks and 2 months[53%(8/15),100%(15/15);60%(9/15),93%(14/15),χ 2=2.863,2.901,P < 0.01].
CONCLUSION: The destroyed hippocampal structure induces the decrease of learning and memory ability of developmental rats. Early interference can increase the quality of neurons and also promote functional development of the nervous system. 相似文献
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79.
作者曾经体外实验证明,均聚寡脱氧胞嘧啶核苷酸片段(dC14)有抗病毒活性,现继续研究其在体内的作用。不给dC14的对照组小鼠,接种腹水瘤细胞后:100%发病和死亡,潜伏期为6d,存活期11d;给每只小鼠dC14 1.3~3.2 mg,发病率和死亡率降低至20%,疾病潜伏期和存活期推迟。在未经dC14处理的种瘤细胞和淋巴组织与经处理的淋巴组织中,多聚酶链反应(PCR)法都检测到病毒核酸,而正常小鼠中则无此种病毒核酸顺序。研究结果提示,dC14对小鼠SRS腹水瘤的发病和生长有抑制作用。此种抑制作用可能是通过抑制病毒基因的表达来实现的。 相似文献
80.
Mapping of the 5' ends of virion-derived hepatitis B virus DNA molecules was carried out after cloning and sequencing linearized genomes made fully double stranded. Of five clones obtained, three of four minus strand termini mapped to the G in position 1826 and one to the T in position 1827. Plus strand 5' ends were more heterogeneous with evidence from one clone for the presence of an RNA-translocated primer from the 5' end of pregenomic RNA as well as two other termini, mapped to positions 1599 and 1601, the second 3' nucleotide of DR2 and the first nucleotide 3' to DR2, respectively. These molecules were also shown to be functional templates for expression of HBcAg after tranfection or microinjection of Huh-7 human hepatoma cells. 相似文献