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101.
本文报告2例食管平滑肌瘤,经食管钡透检查,发现两种新的征象,我们称之为“粘膜折叠征”和“粘膜外凸征”。经食管镜检查与术中观察分析可印证:这两种征象的出现是食管粘膜深陷于肿瘤表面的凹陷处,或深陷于两个肿瘤挤压在一起的间隙中而形成的,而食管壁以外的任何肿瘤压迫食管壁都不可能出现的征象。出现上述两种征象,可以作为食管平滑肌瘤与纵隔肿瘤鉴别诊断的依据,也可以作为多发性食管平滑肌瘤挤压在一起的征象。 相似文献
102.
103.
电针对脊髓损伤早期bcl2mRNA及蛋白表达的影响 总被引:14,自引:0,他引:14
目的:探讨电针治疗脊髓损伤的机制。方法:成年雄性SD大鼠,随机分为模型(MC)组、电针(EA)治疗组、甲基强的松龙(MP)组及假手术(SO)组。采用改良的Allen’s捶击法致大鼠T10脊髓损伤,应用原位杂交和免疫组织化学方法及图像定量分析法观察脊髓损伤早期bcl-2 mRNA和蛋白的表达。结果:MC组脊髓损伤后6h bcl-2 mRNA表达有增高趋势,伤后24h表达增高;伤后6h bcl-2蛋白表达未见明显变化,伤后24h表达有增高趋势。EA组bcl-2 mRNA及蛋白表达均高于模型组,与MP组相比差异无显著性意义。结论:电针可上调bcl-2 mRNA及蛋白的表达,从而抑制细胞凋亡,保护神经细胞。 相似文献
104.
105.
The effects of intracerebroventricular (i.c.v.) and intrathecal (i.t.) 3-isobutyl-1-methylxanthine (IBMX), cholera toxin (CTX) and pertussis toxin (PTX) administration on immobilization-induced antinociception were studied in ICR mice. Antinociception was assessed by the tail-flick assay. Immobilization of the mouse increased inhibition of the tail-flick response for at least 1 h. The pretreatment with i.t. IBMX (0.01-1 ng), but not i.c.v. IBMX, significantly attenuated immobilization-induced inhibition of the tail-flick response. The pretreatments with i.c.v. PTX (0.05-0.5 microg) as well as i.t. CTX, but neither i.c.v. CTX (0.05-0.5 microg) nor i.t. PTX, potentiated the inhibition of the tail-flick response induced by immobilization stress. Our results suggest that spinally located phosphodiesterase appears to be involved in the production of immobilization stress-induced antinociception. In addition, inactivation of supraspinally located PTX-sensitive G-proteins and spinally located CTX-sensitive G-proteins may modulate immobilization stress-induced antinociception. 相似文献
106.
Prognostic significance of c-kit mutation in localized gastrointestinal stromal tumors. 总被引:16,自引:0,他引:16
Tae Won Kim Hyoungnam Lee Yoon-Koo Kang Mi Sun Choe Min-Hee Ryu Heung Moon Chang Jung Sun Kim Jeong Hwan Yook Byung Sik Kim Jung Shin Lee 《Clinical cancer research》2004,10(9):3076-3081
PURPOSE: Constitutive mutational activation of c-kit has been found to be associated with the pathogenesis of gastrointestinal stromal tumors (GISTs). The prognostic significance of c-kit mutations, however, is still controversial. EXPERIMENTAL DESIGN: We examined 86 patients curatively resected for localized GIST. Genomic DNA was extracted from paraffin-embedded tumor tissues. Exons 9, 11, 13, and 17 of the c-kit gene were amplified by PCR and sequenced. RESULTS: Mutations in exon 11 were detected in 61 tumors, and mutations in exon 9 were observed in three tumors, whereas no mutations were detected in exons 13 or 17. The overall c-kit mutation frequency was 74%. Amino acid alterations in the 61 tumors with exon 11 mutations were deletion in 33 tumors, substitution in 20, both deletion and substitution in 4, insertion in 1, and duplication in 3. Histologically, tumors with c-kit mutations showed higher mitotic counts and higher cellularity. The 5-year relapse-free survival (RFS) in patients having GISTs with c-kit mutations was 21%, compared with 60% in those without c-kit mutations. Significantly higher RFS rates were observed in patients with tumors having mitotic counts < 5 mitoses/50 high power field, spindle-cell histology, tumor size < 5 cm, or gastric GISTs. Multivariate analyses indicated association of poorer RFS with a higher mitotic count > or = 5 of 50 high power fields; odds ratio (OR) = 3.0], presence of c-kit mutations (OR = 5.6), and a larger tumor size (> or = 5 cm; OR = 4.2). CONCLUSIONS: The presence of c-kit mutation, along with high mitotic count and larger tumor size, was an independent factor for poor prognosis in patients with localized GISTs. 相似文献
107.
Feliciano García-Vicente Angel Mi?ambres Inmaculada Jerez Ignaci Modolell Leopoldo Pérez Juan Jose Torres 《Radiotherapy and oncology》2003,67(2):239-249
BACKGROUND AND PURPOSE: Modern conformal radiotherapy treatments require accurate dose calculation in any relevant clinical situation. One of these situations is the treatment of lung tumors, where irradiation has to be planned under challenging conditions for dose calculation. In this study we assess the errors in dose values predicted by fast Fourier transform convolution (FFTC) and multigrid superposition (MGS) algorithms implemented in a commercial treatment planning system (TPS). MATERIALS AND METHODS: FFTC and MGS algorithms were used in a FOCUS 3.0.0 (Computerized Medical Systems, USA) to calculate doses in treatment plans using photon beams of 6 and 25 MV nominal energy from a Saturne 43 linac (GE Medical Systems, USA). A 10x10-cm beam irradiating a mediastinum-lung and a thoracic wall-lung-thoracic wall modeled geometry was assessed. The calculated data were compared with measurements performed with radiographic films and ionization chamber. RESULTS: FFTC algorithm leads to an average deviation from ionometric dose measurements of over 10%. Discrepancies between measured and calculated beam fringe values (distance between 50 and 90% isodose lines) of up to 8 mm were observed. For MGS algorithm, all the points assessed in both geometries fulfilled the 3%-3 mm accuracy criteria and the average deviation of absolute dose was about 1%. A maximum of 3 mm deviation in the beam fringe for any depth was found and was within 2 mm beyond the buildup region. Deviations between ionometric and film measurements were within 3%. CONCLUSIONS: MGS algorithm assesses with reasonable accuracy dose distributions and absolute dose in inhomogeneous regions like the lung region. Therefore, and respecting the inhomogeneity dose calculation, the system could be used in routine clinical practice and in dose-escalation programs. This is not true in the case of FFTC algorithm which leads to errors greater than 10% in the absolute dose calculation and underestimates the beam fringe by up to 8 mm. 相似文献
108.
大枣多糖的分离、纯化及分子量的测定 总被引:1,自引:0,他引:1
大枣果肉用乙醇回流脱脂,80~100℃热水浸提,提取液经减压浓缩,乙醇分级沉淀,三氯乙酸脱蛋白,透析,透析内液再经减压浓缩、醇沉得到三个粗多糖ZJ-A’,ZJ-B’,ZJ-C’,ZJ-B’经DEAE-Cellulose柱、Sephacryl S-300柱反复纯化,得大枣多糖ZJ-1、ZJ-2,高效凝胶渗透色谱(HPGPC)和常压凝胶柱色谱分析表明,ZJ-1、ZJ-2为均一多糖,HPGPC法测定分子量(MW)分别为9848、8991,紫外吸收光谱表明,ZJ-1、ZJ-2无核酸和蛋白质的特征吸收峰。 相似文献
109.
目的:探讨癌基因、妊娠性滋养细胞增生程度与葡萄胎恶变的关系。方法:采用针对C-Ha-ras及C-erbB2基因表达产物P21和P185的单克隆抗体进行免疫组织化学染色。检测82例葡萄胎中两种基因产物的表达情况,经2年以上随访证实未发生恶变32例为非恶变组,经手术和临床证实发生恶变50例为恶变组,其中35例行手术治疗。结果:恶变组P21的表达程度低于非恶变组(P=0.0082);P185的表达显著高于非恶变组(P=0.0028)。手术治疗的35例中,恶变后两种基因产物的表达改变较恶变前更明显。两组葡萄胎中滋养细胞增生程度差异无显著性(P=0.413)。不同来源的绒毛膜癌(绒癌)之间及绒癌与侵蚀性葡萄胎(侵葡)之间,P21和P185的表达差异亦无显著性(P=0.268,P=0.719)。结论:P21的低表达及P185的高表达与葡萄胎恶变有关,但与其恶性转化方向无关;滋养细胞增生程度与葡萄胎恶变亦无关。 相似文献
110.
从羊红膻(Pimpinella thellungiana Wolff.)根中分得四个化合物,经理化常数测定和光谱数据解析证明为棕榈酸(Ⅰ)、4-丙烯基苯酚(Ⅱ)、松酯酚(Ⅲ)和新化合物2-甲基-2-羟基-5-甲氧基苯并[d]氢化呋喃-3-酮(Ⅳ)。 相似文献