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71.
目的总结和探讨脑血管造影和载瘤动脉闭塞在治疗颅内巨大动脉瘤上的作用及特点。方法60例颅内巨大动脉瘤患者,根据其脑血管造影的特点采取血管内介入方法[可脱式球囊和(或)弹簧圈]闭塞载瘤动脉近端53例、闭塞载瘤动脉两端后孤立动脉瘤7例;其中23例闭塞前先行颅内-外血管搭桥术。结果出院时Rankin评分分级:单纯血管内介入治疗组37例中轻残3例,合并颅内-外血管搭桥术组23例中死亡1例、重残2例。1-6年的影像学随访动脉瘤无复发。结论血管内介入结合颅内-外血管搭桥术闭塞载瘤动脉是治疗颅内巨大动脉瘤的方法之一。  相似文献   
72.
Serine hydroxymethyltransferase (SHMT) provides activated one-carbon units required for the biosynthesis of nucleotides, protein, and methyl group by converting serine and tetrahydrofolate to glycine and N(5),N(10)-methylenetetrahydrofolate. It is postulated that SHMT activity is associated with the development of methotrexate resistance and the in vivo activity of SHMT is regulated by the binding of N(5)-CHO-THF, the rescue agent in high-dose methotrexate chemotherapy. The aim of this study is to advance our understanding of the folate-mediated one-carbon metabolism in zebrafish by characterizing zebrafish mitochondrial SHMT. The cDNA encoding zebrafish mitochondrial SHMT was cloned, overexpressed in Escherichia coli, and purified with a three-step purification protocol. Similarities in structural, physical, and kinetic properties were revealed between the recombinant zebrafish mitochondrial SHMT and its mammalian orthologs. Surprisingly, leucovorin significantly inhibits the aldol cleavage of serine catalyzed by zebrafish cytosolic SHMT but inhibits to a lesser extent the reaction catalyzed by the mitochondrial isozyme. This is, to our knowledge, the first report on zebrafish mitochondrial folate enzyme as well as the differential inhibition of leucovorin on these two SHMT isoforms. Western blot analysis revealed tissue-specific distribution with the highest enrichment present in liver for both cytosolic and mitochondrial SHMTs. Intracellular localization was confirmed by confocal microscopy for both mitochondrial and cytosolic SHMTs. Unexpectedly, the cytosolic isoform was observed in both nucleus and cytosol. Together with the previous report on zebrafish cytosolic SHMT, we suggest that zSHMTs can be used in in vitro assays for folate-related investigation and antifolate drug discovery.  相似文献   
73.
Changes in T .lymphocyte subsets after severe traumatic brain inJury   总被引:2,自引:0,他引:2  
BACKGROUND: Besides local changes of cranial parenchymal cells, hemorrhage, etc., severe traumatic brain injuries also cause the changes of total body fluid and various functions, and the changes of lymphocytes and T lymphocyte subsets should be paid more attention to. OBJECTIVE: To reveal the changing laws of T lymphocyte subsets after severe traumatic brain injury, and compare with mild to moderate brain injury. DESIGN: A comparative observation. SETTINGS: Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City; Central Laboratory of Shenzhen Hospital of Prevention and Cure for Chronic Disease. PARTICIPANTS: All the subjects were selected from the Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City from August 2002 to August 2005. Thirty patients with severe brain injury, whose Glasgow coma score (GCS) was ≤ 8 points, were taken as the experimental group, including 21 males and 9 females, aging 16 - 62 years. Meanwhile, 30 patients with mild traumatic brain injury were taken as the control group (GCS ranged 14- 15 points), including 18 males and 12 females, aging 15 -58 years. All the subjects were in admission at 6 hours after injury, without disease of major organs before injury Informed consents were obtained from all the patients or their relatives. METHODS: (1) The T lymphocytes and the subsets in peripheral blood were detected with immunofluorescent tricolor flow cytometry at l, 3, 7 and 14 days after injury in both groups. (2) The conditions of pulmonary infections were observed at 4 days after injury. The differences of measurement data were compared with the t test. MAIN OUTCOME MEASURES: Changes of T lymphocytes subsets at 1 - 14 days after severe and mild or moderate traumatic injury. RESULTS: Finally, 28 and 25 patients with mild to moderate traumatic brain injury, whereas 25 and 21 patients with severe traumatic brain injury were analyzed at 7 and 14 days respectively, and the missed ones died due to the development of disease. (1) Changes of T lymphocyte subsets: At 1 and 3 days after injury, CD3, CD4, CD8, CD4/CD8 began to decrease, whereas CD8 increased in the experimental group, which were very significantly different from those in the control group (t =2.77 - 3.26, P 〈 0.01), and began to recover at 7 days, which were significantly different from those in the control group (t = 2.06 - 2.24, P 〈 0.05), and generally recovered to the normal levels at 14 days (P 〉 0.05). (2) Conditions of pulmonary infections: At 4 days after injury, the rate of pulmonary infection was significantly different between the experimental group and control group [73% (22/30), 0, x2=37.29, P 〈 0.01]. CONCLUSION: Patients with severe traumatic brain injury suffer from damages of cellular immune function at early period (within 7 days), and they are easily to be accompanied by pulmonary infections.  相似文献   
74.
Objective: To study the diagnostic value of T2^*-weighted first-pass perfusion imaging in breast tumors. Methods: We analyzed the magnetic resonance imaging (MRI) information along with the pathological and immunohistochemistry results. Magnetic resonance imaging was performed in 28 patients with breast tumor. The time to signal intensity curves were generated according to the T2^*-weighted first-pass perfusion imaging. The curve's maximal signal intensity drop rate and maximal signal intensity decrease time were analyzed and compared with the pathological diagnoses after surgery. Results: Malignant breast lesions showed higher maximal signal intensity drop rate (44.69% ± 17.07 vs. 17.22% ±7.49, P 〈 0.001) than benign lesions, but there was no significant difference of maximal signal decrease time between those two lesions (23.94 s ± 4.92 vs. 20.02 s ± 6.83, P 〉 0.05). Conclusion: The T2^*-weighted first-pass perfusion imaging has enough sensitivity and specificity in breast tumor diagnosis.  相似文献   
75.
以钒基核苷酸复合物为核酸酶抑制剂,从人胚组织中制备总RNA,所得产品几乎不含DNA和蛋白质,经过分离Poly(A)~ mRNA,证明制品有合成cDNA的完整功能,方法比较简捷,适于大量制备以满足分离mRNA 之需,并讨论了此法的优缺点。  相似文献   
76.
Monoclonal antibody 131I-COC183B2, developed in our laboratory and proved to fit for human treatment was injected intraperitoneally or subcutaneously in 13 patients. In 8 cases with i.p. injection the disease corresponded with the image, i.e. 3 primary ovarian epithelial cancers showed positive images, 1 ovarian Krukenberg tumor was negative and the other 4 negative images included 1 uterine myoma and 3 ovarian teratomas. In the subcutaneous injection group, 4 cases had ovarian carcinoma, surgery and chemotherapy. Two negative images corresponded with the clinical status-in good health, another negative case had metastatic left supraclavicular lymph node due to ovarian mucinous adenocarcinoma. The last negative image in this group was a case of benign ovarian teratoma which was proved after surgery. The 1 positive case was waiting to be proved by a scheduled third operation. The computer scintigram calculation of T/NT was 5.35 to 13.7. The results suggest that this monoclonal antibody can be used for radioimmunoimaging for the localization of ovarian carcinoma, which is not only helpful for clinical staging and differential diagnosis but is also a good follow-up method.
  相似文献   
77.
p16INK4A (p16) binds to cyclin-dependent kinase 4/6 and negatively regulates cell growth. Recent studies have led to an understanding of additional biologic functions for p16; however, the detailed mechanisms involved are still elusive. In this article, we show an unexpected expression of anion exchanger 1 (AE1) in the cytoplasm in poorly and moderately differentiated gastric and colonic adenocarcinoma cells and in its interaction with p16, thereby sequestrating the protein in the cytoplasm. Genetic alterations of p16 and AE1 were not detectable. Forced expression of AE1 in these cells sequestrated more p16 in the cytoplasm, whereas small interfering RNA-mediated silencing of AE1 in the cells induced the release of p16 from the cytoplasm to the nucleus, leading to cell death and growth inhibition of tumor cells. By analyzing tissue samples obtained from patients with gastric and colonic cancers, we found that 83.33% of gastric cancers and 56.52% of colonic cancers coexpressed AE1 and p16 in the cytoplasm. We conclude that AE1 plays a crucial role in the pathogenesis of gastric and colonic adenocarcinoma and that p16 dysfunction is a novel pathway of carcinogenesis.  相似文献   
78.
目的:观察超声电丛刺头穴丛刺法治疗急性脑梗死的效果,以及治疗前后体感诱发电位指标及血液生化指标变化。方法:①选择2003-01/2005-06在沈阳脑科医院神经内科住院的急性脑梗死患者261例,男160例,女101例。均为首次患病,且对治疗方案知情同意。将上述患者随机分为2组:丛刺治疗组131例,对照组130例。②丛刺治疗组:采用超声电丛刺治疗仪于头部电丛刺顶区(运动区),以100~200Hz疏密波电针通过6~8h,1次/d,1个疗程30次。对照组:均予以常规脑血管病药物同等治疗。丛刺治疗组和对照组均干预30d。两组疗效判定标准:治疗后神经功能缺损评分减少91%~100%为基本恢复,减少46%~90%为显著进步,减少18%~45%为进步。③采用酶联免疫法测定血浆α-颗粒膜蛋白水平;应用放射免疫法测定血浆血栓素A2水平;采用酶联免疫吸附法双抗体夹心法测定血浆D-二聚体水平;采用免疫透射比浊方法测定脂蛋白(a)水平。应用神经电生理检测仪检测体感诱发电位。④计数和计量资料差异比较采用χ2检验和t检验。结果:急性脑梗死患者261例均进入结果分析。①丛刺治疗组131例中:基本恢复31例,显著进步80例,进步15例,总有效率为96%(126/131);对照组130例:基本恢复14例,显著进步68例,进步12例,总有效率为72%(96/130);丛刺治疗组总有效率明显高于对照组(P<0.01)。②丛刺治疗组治疗后血浆α-颗粒膜蛋白、血栓素A2、D-二聚体和脂蛋白(a)含量较治疗前明显降低(P<0.01)。③丛刺治疗组治疗后体感诱发电位的波潜伏期与传导时间较治疗前明显缩短(P<0.01)。结论:超声电丛刺治疗急性脑梗死效果显著,可显著改善急性脑梗死患者体感诱发电位指标及血液生化指标。  相似文献   
79.
创伤性浮膝伴血管损伤的早期诊治   总被引:3,自引:0,他引:3  
目的 探讨创伤性浮膝同时伴同侧血管损伤患者的早期诊断及救治.方法 总结1996年6月~2002年12月收治28例30个浮膝的手术固定方法、血管修复情况及术后治疗和恢复情况.结果 术后伤口一期愈合5例,17例伤口二期行植皮修复,4例胫前骨折部外露二期行皮瓣转移术,截肢2例,保肢成功率92.9%.术后26例经18个月~8年随访,骨折均愈合,下肢功能恢复优良率64.3%.结论 对浮膝损伤患者应高度重视伴有血管损伤可能,早期作出诊断,积极合理治疗,对患者预后至关重要.  相似文献   
80.
目的探讨NeuroformⅡ支架植入联合MatrixⅡ弹簧圈栓塞治疗颅内宽颈动脉瘤的疗效、技术要点、安全性及并发症防治。方法诊断为颅内宽颈动脉瘤的病人11例,其中大脑前动脉瘤2例,后交通动脉瘤4例,眼动脉瘤1例,大脑中动脉瘤2例,椎基底动脉瘤2例。7例先行NeuroformⅡ支架瘤颈成形,将微导管通过支架网眼置入动脉瘤内,填塞弹簧圈;4例先置入微导管于动脉瘤内,再释放支架后栓塞,术后3~6个月随访。结果所有病例栓塞操作均顺利完成,无手术并发症;其中致密填塞8例,部分致密填塞3例,术后病人均恢复良好,4例短期随访无再出血及血栓栓塞症状发生。结论NeuroformⅡ支架联合MatrixⅡ弹簧圈治疗颅内宽颈动脉瘤安全、有效。  相似文献   
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