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91.
目的 :研究抑癌基因p15、Rb蛋白表达对喉鳞状细胞癌诊断、治疗及预后判断的意义。方法 :用免疫组化SABC法检测喉癌组 45例石蜡标本与对照组 15例喉部正常或增生的黏膜上皮标本的 p15、Rb蛋白表达情况。结果 :喉鳞状细胞癌组p15蛋白阳性率 (48.9%)与对照组阳性率 (10 0 .0 %)比较 ,差异有极显著性意义 (P<0 .0 1) ;喉癌组中 0~Ⅱ期 p15蛋白阳性率 (6 6 .7%)与Ⅲ~Ⅳ期阳性率 (33.3%)比较 ,差异有显著性意义 (P <0 .0 5 ) ;喉癌组Rb蛋白阳性率 (88.9%)与对照组阳性率 (93.3%)比较 ,差异无显著性意义 (P >0 .0 5 ) ;2× 2列联表 χ2 检验 ,p15、Rb蛋白表达无相关性 (P >0 .0 5 ) ;对照组中 ,p15蛋白的表达以鳞状上皮组织中远离基膜的棘层细胞、颗粒层细胞明显 ,而Rb蛋白的表达则以基底层细胞及近侧棘层细胞明显。结论 :抑癌基因 p15的表达缺失对喉鳞状细胞癌的发生、发展有一定的作用 ,p15蛋白的检测对喉鳞状细胞癌的治疗及估计预后有指导意义 ;喉鳞状细胞癌组织中 p15、Rb的蛋白表达无相关性 ;正常及增生的喉部鳞状上皮的细胞层次间 ,p15、Rb蛋白表达不一致 ,p15蛋白表达对细胞增殖有抑制作用。 相似文献
92.
T.W.‐M. Fan A.N. Lane E. Chekmenev R.J. Wittebort R.M. Higashi 《Chemical biology & drug design》2004,63(3):253-264
Abstract: Soil humic substances (HS) are heterologous, polydispersive, and multi‐functional organometallic macromolecules ubiquitous in soils and sediments. They are key players in the maintenance of the belowground ecosystems and in the bioavailability of both organic and inorganic contaminants. It is widely assumed that the peptidic substructures of HS are readily degraded and therefore do not contribute significantly to interactions with contaminants such as toxic metals. To investigate the turnover of humified peptides, laboratory soil aging experiments were conducted with 13C‐glucose or 15N‐nitrate for 8.5 months. Evidence for random‐coil peptidic structures in the labeled HS was obtained from 2‐D nuclear magnetic resonance (NMR), pyrolysis gas chromatography‐mass spectrometry (pyro‐GC‐MS), and circular dichroism data. Interaction of metals with the peptidic carbonyls of labeled HS was rationalized from the solid‐state NMR data. Detailed 13C and 15N labeling patterns of amino acid residues in the acid hydrolysates of HS acquired from NMR and GC‐MS revealed two pools of peptides, i.e. one extant (unlabeled) and the other, newly humified with little isotopic scrambling (fully labeled). The persistence of pre‐existing peptidic structures indicates their resistance to degradation while the presence of fully labeled peptidic amino acids suggests wholesale incorporation of newly synthesized peptides into HS. These findings are contrary to the general notion that humified peptides are readily degraded. 相似文献
93.
用免疫组化ABC法和IRMA法分别检测了42例乳腺癌和30例良性乳腺病变患者组织中Ha-ras基因蛋白(rasP21)的表达状况及血清CA15-3值,结果恶性病变组织中rasP21呈过度表达,rasP21的表达与细胞的分化状态密切相关。不同淋巴结转移状况的乳腺癌患者,其血清CA15-3差异呈显著性。CA15-3水平的变化与rasP21表达状况显著相关。提示血清CA15-3水平为监测乳腺癌病情变化的良好指标,Ha-ras癌基因点突变的结果可能导致乳腺癌相关抗原的异常分泌。 相似文献
94.
Recent molecular cytogenetic studies have elucidated the origin and nature of extra structurally abnormal chromosomes (ESACs)
or small supernumerary chromosomes, which are often associated with developmental delay and malformations. We studied the
prevalence of inv dup(15) in a nationwide screening programme for mentally retarded children in Taiwan and tried to correlate
the genotype and phenotype in those patients. Fluorescence in situ hybridization (FISH) analysis using D15Z, D15Z1, and the
cosmids from the Prader-Willi/Angelman syndrome chromosome region (PW/ASCR) was performed on 54 patients (0.45%) with ESACs
from 11893 probands within a 5-year period. Of them, inv dup(15) was confirmed in 25 children (46.3%) by FISH analysis. The
PW/ASCR probes were used to clarify the size and DNA composition of the markers. Patients with inv dup(15) chromosomes, containing
only the heterochromatin or little euchromatin of the proximal 15q (i.e., pter→q11:q11→pter) may have a rather mild or nearly
normal phenotype (group 1). Only one patient had some features suggestive of Angelman syndrome, but was considered to be a
result of deleted (15)(q12) in the chromosome 15 homologue. Additional copies within D15S11 through GABRB3 (15q11.2-13) resulted
in an abnormal phenotype which involved mental and developmental delay but was different from the classical phenotype of PW/AS
(groups 2, 3). Signs of autistic behavior did occur in each group. FISH combined with microsatellite analyses showed that
the marker was often of maternal origin in de novo cases (n = 12, 86%), or inherited from the mother in only one familial case. Down-inv dup(15) was mentioned in two cases. Unusual
features including diaphragmatic eventration, hyperlaxity of joints, arachnodactyly, brain atrophy, epilepsy (particularly
infantile spasm), ataxia, genital abnormalities, and cleft lip/palate were noted in those patients. This observation expands
the range of phenotypic expression associated with this relatively common ESAC.
Conclusion Marked phenotypic diversities exist in children with inv dup(15), dependent upon the size or genetic composition of the markers,
degree of mosaicism, parental origin and familial occurrence or not. Patients with a larger inv dup(15) marker chromosome
including the PW/ASCR may have a higher risk of abnormalities, but not the typical Prade-Willi/Angelman syndrome phenotype.
Received: 11 February 1997 and in revised form: 20 May 1997 / Accepted: 20 May 1997 相似文献
95.
D. A. Garteiz T. Madden D. E. Beck W. R. Huie K. T. McManus J. L. Abbruzzese W. Chen R. A. Newman 《Cancer chemotherapy and pharmacology》1998,41(4):299-306
A highly sensitive and specific assay for the quantitation of the anticancer agent dolastatin-10 (DOL-10) in human plasma
is described. The method was based on the use of electrospray ionization-high-performance liquid chromatography/mass spectrometry
(ESP-LC/MS). The analytical procedure involved extraction of plasma samples containing DOL-10 and the internal standard (DOL-15)
with n-butyl chloride, which was then evaporated under nitrogen. The residue was dissolved in 50 μl mobile phase and 10 μl was subjected
to ESP-LC/MS analysis using a C18 microbore column. A linear gradient using water/acetonitrile was used to keep the retention times of the analytes of interest
under 5 min. The method exhibited a linear range from 0.005 to 50 ng/ml with a lower limit of quantitation (LLQ) at 0.005 ng/ml.
Absolute recoveries of extracted samples in the 85–90% range were obtained. The method's accuracy (≤5% relative error) and
precision (≤10% CV) were well within industry standards. The analytical procedure was applied to extract DOL-10 metabolites
from samples obtained following incubation of the drug with an activated S9 rat liver preparation. Two metabolic products
were detected and were tentatively identified as a N-demethyl-DOL-10 and hydroxy-DOL-10. Structural assignments were made based on the fragmentation patterns obtained using the
electrospray source to produce collision-induced dissociation (CID). The method was also applied to the measurement of DOL-10
in the plasma of patients treated with this drug. Preliminary investigation of the pharmacokinetics suggested that drug distribution
and elimination may be best described by a three-compartment model with t1/2α = 0.087 h, t1/2β = 0.69 h and t1/2γ = 8.0 h. Plasma clearance was 3.7 l/h per m2.
Received: 17 March 1997 / Accepted: 13 June 1997 相似文献
96.
IL-15对儿童MDS造血前体细胞bcl-2、bcl-xl mRNA表达的影响 总被引:1,自引:0,他引:1
目的 探讨IL-15对骨髓增生异常综合征(MDS)造血细胞bcl-2、bcl—xl mRNA表达的影响,以探索IL-15抑制MDS CD34^ 造血干/祖细胞凋亡的可能机制:方法 采用吸附单克隆抗体的免疫磁珠分离系统,分离纯化17例MDS患儿骨髓CD34^ 细胞,采用RT—PCR检测bcl-2、bcl—xl mRNA表达水平,观察IL-15对它们的影响。结果 IL-15可呈时间与剂量依赖性的增强体外培养的MDS造血前体细胞bcl-2、bcl—xl基因mRNA的表达。结论 IL-15可能为抑制MDS CD34^ 造血干/祖细胞凋亡的作用机制之一。 相似文献
97.
骨髓增生异常综合征造血前体细胞对白细胞介素15反应的研究 总被引:1,自引:0,他引:1
目的 探讨儿童骨髓增生异常综合征 (MDS)造血前体细胞对白细胞介素 15 (IL 15 )的反应 ,为临床应用提供理论依据。方法 采用吸附单克隆抗体的免疫磁珠分离系统分离纯化 18例MDS患儿骨髓CD3 4 细胞 ,采用碘化丙锭染色、流式细胞仪分析和细胞核形态检测两种方法同时检测体外培养MDS造血前体细胞增殖、分化过程中的凋亡状况 ;观察IL 15对其影响 ,并进行定量分析。结果 在培养d8,IL 15浓度在 0~ 10 0ng/ml可呈剂量依赖性地抑制体外培养MDS骨髓造血前体细胞的凋亡。结论 IL 15可部分抑制体外培养的MDS造血前体细胞凋亡 相似文献
98.
甲硫腺苷磷酸化酶在非小细胞肺癌中转录表达 总被引:1,自引:0,他引:1
目的 探讨甲硫腺苷磷酸化酶(MTAP)及其连锁基因p14,p15和p16在非小细胞肺癌中的转录表达变化情况。方法 采用RT-PCR方法检测15例新鲜肺癌标本及相应癌旁组织中MTAP及其边锁基因p14、p15和p16mRNA的表达情况。结果 MTAP在73.3%的肿瘤标本中不表达或转录水平降低5倍以上,而MTAP在癌旁对照组织中的表达率却高达93.3%;此外,MTAP在肺腺癌和鳞癌中的低表达现象无显著性差异,但在中/低分化肺癌中低表在显著高于高于分化癌。对7例标本分析表明,1例P15基因在正常组织及癌瘤中都高水平表达,1例均不表达。5例在癌标本中基本不表达.而在正常组织中表达;而p14和p16正常组织中转录表达水平很低,而在配对的7例肺癌组织中却分别有3项高表达。结论 MTPA基因低表达或丢失可能与肺癌的恶性程度密切相关,MTAP的缺失可能独立于p16之外,提示MTAP的低表达或缺失在肿瘤生物学中有其功基础的基础。 相似文献
99.
目的建立转人白细胞介素-15(hIL-15)基因的喉癌细胞株,并研究hIL-15的表达情况。方法将携带人白细胞介素-15的质粒pcDNA3.1( )-hIL-15转导入人喉表皮样癌细胞Hep-2中,G418筛选阳性克隆,RT-PCR、Westernblot和ELISA法对hIL-15的表达进行检测。结果IL-15基因成功地转导入Hep-2细胞中并能高效表达。RT-PCR电泳结果显示hIL-15基因在mRNA水平有表达;ELISA法测得106个转染阳性细胞24h内培养上清液中hIL-15的含量为(185.0±12.2)pg/ml,空载体转染及未转染的细胞未检测到hIL-15。结论hIL-15基因成功转染人喉癌细胞系Hep-2细胞且能持续大量表达。 相似文献
100.
目的研究多肿瘤标志物蛋白芯片诊断系统用于胃癌的诊断价值。方法用多肿瘤标志物蛋白芯片诊断系统检测50例正常人,70例胃良性疾病及80例胃癌患者血清中十二种常见的肿瘤标志物:甲胎蛋白(AFP),癌胚抗原(CEA),神经元特异性烯醇化酶(NSE),糖原125(CA125),糖原153(CA153),糖原242(CA242),糖原199(CA199),前列腺特异性抗原(PSA),游离前列腺特异性抗原(f-PSA),铁蛋白(FER),β-人绒毛膜促性腺激素(β-HCG),人生长激素(HGH)的水平并进行统计学分析。结果80例胃癌患者血清有74例血清肿瘤标志物为阳性(阳性率为92.75%),70例良性胃疾病中10例肿瘤标志物为阳性(阳性率为14.28%),50份正常对照血清有1例血清肿瘤标志物为阳性(特异性为98%)。试验还发现部分胃癌患者血清中出现NSE,HGH,PSA,f-PSA。结论多肿瘤蛋白芯片的应用,对胃癌患者的术前肿瘤良恶性的判定有一定的临床应用价值。 相似文献