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71.
目的:提高对小儿早期睾丸卵黄囊瘤的诊断与治疗水平。方法:回顾性分析12例小儿早期睾丸卵黄囊瘤的病例资料。结果:12例患者术前行阴囊B超示睾丸增大,内部回声不均匀,7例可见睾丸内积液改变;甲胎蛋白(AFP)值均明显升高。12例均行根治性睾丸切除术,术后行病理检查确诊。术前、术后均未行化疗,9例随诊5年未见复发,2002年就诊的3例目前未见复发症状。结论:小儿早期睾丸卵黄囊瘤可根据相关检查结果,结合病理检查确诊。治疗方法为行根治性睾丸切除,可不作化疗,预后较好。 相似文献
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73.
目的 将人乳头瘤病毒16型(Human papillomavirus type 16,HPV-16)的晚期表达蛋白E7上的抗原24肽(从第38位氨基酸到第61位氨基6病毒感染防治酸)与人免疫球蛋白G的重链恒定区融合表达,并以此融合蛋白作为抗原,可能为HPV-1提供免疫治疗方法。方法 利用PCR方法分别扩增HPV-16 E7(38-61)24肽的DNA片段和人免疫球蛋白G的重链恒定区DNA片段,并构建到pEV21a表达载体上,转化入E.coli中表达,利用SDS-聚丙烯酰胺凝胶电泳(SDS-PAGE)和蛋白质免疫印迹(Western-blotting)的方法对表达结果进行鉴定。结果 构建的表达载体HPV16E7e/hIgGHCCR-pET21a经酶切鉴定和测序显示序列正确;通过SDS-PAGE和Western-blotting的鉴定,重组融合蛋白Mr约40000,表达量可占菌体蛋白的20%左右。结论 成功构建HPV16-E7的抗原多肽片段和人免疫球蛋白G的重链恒定区的融合蛋白,并可在E.coli中高效表达。 相似文献
74.
目的:观察腰麻辅助硬膜外麻醉在全子宫切除术中的应用效果。方法:选择328例全子宫切除术病人,随机分为试验组(143例)、对照组(185例),均取L_(1-2)棘突间隙行硬膜外腔穿刺置管,对照组常规用药,试验组另取L_(3-4)棘突间隙行腰麻,观察各组的麻醉效果,术中探查牵拉子宫时病人的反应,血压及心率的变化。结果:试验组的麻醉良好率、肌松情况优于对照组(P<0.01),骶神经阻滞情况试验组完全阻滞,而对照组出现骶神经阻滞不全,首次剂量试验组少于对照组(P<0.01)。牵拉子宫后各组病人血压、心率均较牵拉前下降,且与牵拉前比较有显著差异(P<0.05)。结论:在全子宫切除术中应用腰麻辅助硬膜外麻醉优于单纯硬膜外麻醉,有一定临床应用意义。 相似文献
75.
茶氨酸对脑缺血再灌注损伤保护作用的实验研究 总被引:13,自引:0,他引:13
目的观察茶氨酸对脑缺血再灌注损伤的保护作用,为临床脑缺血再灌注损伤的预防和治疗提供实验依据。方法将24只健康家兔随机分为四组:假手术组、脑缺血组、茶氨酸予处理组和茶氨酸治疗组。麻醉后分离血管,采用基底动脉、双侧颈总动脉结扎法制备急性全脑缺血再灌注动物模型。假手术组仅分离动脉不结扎,予处理组在缺血前应用茶氨酸,治疗组在缺血后应用茶氨酸,缺血组不作特殊药物处理。各组分别在规定时间点即缺血前、再灌注后30min、1h、2h采血测定神经特异性烯醇化酶(NSE)含量,取脑组织活检观察超微结构,处死动物测定脑含水量。结果茶氨酸予处理组和治疗组以上各项指标均较脑缺血组有显著的改善,提示茶氨酸具有神经保护作用。实验还显示茶氨酸予处理组在再灌注30min时NSE含量与假手术组比较无差异,提示用茶氨酸予处理后可能使缺血后脑损害的发生延迟,为进一步的治疗争取了宝贵时间。结论茶氨酸对脑缺血再灌注损伤有保护作用,值得进一步研究。 相似文献
76.
闭合复位空心钉治疗中老年股骨颈骨折后股骨头坏死的多元相关研究 总被引:9,自引:0,他引:9
目的探讨影响闭合复位空心钉治疗中老年股骨颈骨折后股骨头坏死的相关因素及其多元关系。方法对1999年5月~2004年5月间收治的300例中老年股骨颈骨折患者进行回顾性分析,所有患者均行闭合复位空心钉固定。对随访资料完整的99例患者资料运用SPSS10.0软件进行统计学分析,即对其年龄、性别、骨折类型、复位时间、复位质量、完全负重时间、内固定是否取出及术前是否行牵引等因素进行多因素分析。结果99例患者获平均24.5个月(8~60个月)随访。15例出现股骨头坏死,坏死率为15.2%,发生坏死的时间为术后8~50个月。由复位质量、术前牵引、年龄及年龄×取出内固定构成的多因素组对股骨颈骨折后股骨头坏死的影响最显著。结论闭合复位质量对股骨颈骨折预后的影响程度极大;不良位置的术前牵引可能加重股骨头坏死;年龄在多因素共同影响中的相对危险度不大;Garden分型是判断股骨颈骨折后股骨头坏死的一项重要指标,与骨折复位质量具有相关性,但其并非是多因素共同影响下造成股骨头坏死的危险因素。 相似文献
77.
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
78.
79.
主要通过医学生的视角,从教学内容、教学方法等方面谈了对医学伦理学教育的感受和一些建议,并通过医学生的声音反映医学伦理学教育的成果以及存在的一些问题。 相似文献
80.
Wei GONG Zhuo-Jing LUO Hua HAN Hong-Yan QIN You-Biao CHU Xue-Yu HU Li-Feng LAN Department of Orthopaedics XiJing Hospital the Fourth Military University Xi''''an China 《中国神经科学杂志》2006,(1)
Objective To invest the efficient method which can culture and induce embryonic stem cells to neurocyte in vitro. Methods Isolate the blastula of 3.5 d from BALB/c species mouse. Culture the cells from inner cell mass (inner cell mass, ICM) which were isolated by mechanical method on the mouse embryonic fibroblaste cell (MEF) feeder layer or 0.1% gelatin coated dishes. The stem cells were identified by characterized morphology, alkaline phosphatase stain, differential potency in vivo and immunochemistry stain. The isolated cells were differentiated by serial induction method that mimicking the intrinsic developmental process of the neural system. Results The isolated cells were positive for alkaline phosphatatse and SSEA-1 (stage specific embryonic antigen 1). Moreover they were identified pluripotent by differentiation in vivo. Therefore the isolated cells presented the characters of ESCs. Then the isolated cells were able to differentiate into neurocytes in vitro. Conclusion Mouse embryonic stem cells isolation, culture and differentiation system has been established. 相似文献