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101.
目的:寻找一种性能优良的拓扑指数,方法:根据分子图的邻接矩阵和距离矩阵提出一种新的拓扑指数P1^*,P2^*,P3^*,p^4*。结果,拓扑指数P1^*,P2^*,P3^*,p^4*与烯烃的热力学函数-△Hf(g),S(g),△Gf(g)均有相关性,其复相关系数均在99.6%以上。结论:拓扑指数P1^*,P2^*,P3^*,p^4*与烯烃的热力学函的多种物理化学性质均有良好的相关性。  相似文献   
102.
目的:对硬脑膜动静脉瘘临床诊断治疗特点进行探讨。方法:对60例患者行血管内栓塞治疗,5例行颈动脉压迫法治疗。其中13例1次栓塞,25 例行2次栓塞,17例行3次栓塞,5例行4次或多次栓塞,结果:治愈36例,好转25例,4例无效,无一例死亡,结论:硬脑膜动静脉瘘的临床表现和预后与其发病部位,静脉引流类型密切相关,颈动脉压迫法及选择性血管内栓塞是安全有效的治疗方法。  相似文献   
103.
组织多肽特异性抗原在原发性肝癌中的临床应用   总被引:2,自引:0,他引:2  
OBJECTIVE: To evaluate the clinical value of serum tissue polypeptide specific antigen (TPS) for primary hepatic cancer in comparison with alpha-fetoprotein (AFP). METHODS: TPS and AFP were measured by enzyme-linked immunosorbent assay (ELISA) in 85 patients with primary hepatic cancer, 19 with metastatic hepatic cancer, 35 with liver cirrhosis, 22 with chronic hepatitis and 50 healthy control subjects. RESULTS: Serum AFP levels were elevated in patients with hepatocellular carcinoma in comparison with that in cholangiocarcinoma patients (P=0.037), but the difference was not significant (P=0.737). Serum TPS levels were significantly correlated with the tumor size (P=0.001), but not with the number of the tumors, portal invasion, extrahepatic metastasis, clinical stage or histological differentiation (P>0.05). A significant correlation was observed between AFP level and tumor size (P=0.028), portal invasion(P=0.005), and histological differentiation (P=0.000). CONCLUSION: TPS alone offers no more clues than AFP for the diagnosis of primary hepatic cancer, though it can be helpful for the diagnosis of cholangiocarcinoma. It has only limited clinical utility as a marker for primary hepatic cancer.  相似文献   
104.
神经干细胞静脉移植治疗脊髓损伤的实验研究   总被引:3,自引:0,他引:3  
[目的]观察神经干细胞静脉移植对损伤大鼠脊髓功能的治疗作用。[方法]取孕14—16dSD胎鼠的脑室下区组织,体外培养后鉴定细胞。制作脊髓全切模型,伤后1周将Brdu标记好的神经干细胞通过尾静脉注射移植到大鼠体内,移植后及8周行皮层体感诱发电位(CSEP)检测和BBB功能评分,并留损伤脊髓处作病理切片及免疫组化染色。[结果](1)移植后8周BBB评分损伤组、移植组都有所恢复,但都未达到正常水平,移植组恢复较好;(2)模型制作后,CSEP波均消失,细胞移植后8周移植组的波形有不同程度的恢复,但潜伏期延长;(3)移植组大鼠脊髓损伤处存在大量Brdu染色阳性细胞,表明移植的细胞在体内可到达损伤脊髓处并能存活;脊髓损伤部位NF-200及GFAP染色阳性的细胞表明移植的细胞可以分化为具有神经元和胶质细胞特性的细胞。[结论]静脉移植的神经干细胞能到达损伤区代替受损的神经元及神经胶质细胞,使损伤的脊髓功能得到一定程度的恢复。  相似文献   
105.
自拟育精散治疗男性不育症127例   总被引:1,自引:0,他引:1  
男性不育症所致的病因较多,精液异常是常见病因,约占85%以上。自2000年以来,笔者用白拟育精散治疗精液异常导致的男性不育症,取得较好的疗效,结果报道如下。  相似文献   
106.
OBJECTIVES: To explore the morphological and functional findings of transvaginal sonography (TVS) in the diagnosis and management of distal ureteral calculi. METHODS: We retrospectively reviewed the imaging studies in seven cases of distal ureteral calculi (study group) and 20 cases of female volunteers without urinary tract infection (control group). All 27 patients had undergone TVS for assessment of the lower urinary tract. The variables measured on ultrasound included the presence or absence of distal ureteral calculi, the size and location of a calculus if present, the presence or absence of the ureter jet phenomenon, morphological changes of the ureteral papilla and adjoining tissue, and the height of the ureteral papilla, as well as vascular changes seen on Doppler imaging. RESULTS: In the controls, 80% of the ureteral papillae were triangular and 20% trapezoidal. The average (+/-SD) height of the ureteral papillae was 3.5 +/- 0.7 mm on the right and 3.6 +/- 0.9 mm on the left. There was no statistically significant difference between the heights of the right and left papillae (P = 0.619). In the study group, echogenic stones were identified in all seven patients and a hypoechogenic tubular structure connected to the involved papilla was identified in 6/7 patients. The average height of the involved papilla was 6.7 +/- 1.6 mm. Ureteric jets were visible in all patients in both the study and control groups. CONCLUSION: In patients with distal ureteral calculi, TVS provides a rapid, non-invasive and repeatable means of assessing the morphology and function of the distal ureter.  相似文献   
107.
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   
108.
目的了解温州口岸出入境人员中的心房颤动的发生情况,探讨旅行保健方法。方法对检出的48例心房颤动患者的资料进行分析。结果对2003.11-2004.10从温州口岸出入境的19862名人员进行心电图检查,发现心房颤动病例48例,检出率为0.24%,其中男性29例,女性19例,男女之间检出率没有显著差异。心房颤动多见于老年人。结论出入境人员进行健康体检具有重要意义。确保出入境人员的健康。  相似文献   
109.
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   
110.
本文总结了椎管内神经鞘膜肿瘤的MRI表现并与病理结果进行了对照。MRI诊断准确率为82.6%。哑铃征及弄清脊髓与肿瘤的关系是MRI诊断椎管内神经鞘膜肿瘤的要点,本组病例哑铃征出现率为42.1%。但椎管内神经鞘膜肿瘤的MR信号变化与脊膜瘤和室管腆窟无法区分。  相似文献   
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