TiAl合金细小全层片组织形成机理

根据对细小全层片组织及其高温转变中间组织的金相和电镜观察分析结果，提出了一种新的双相钛铝合金全层片组织形成机理，即γ／α层片结构在α单相区温度下沿γ相基体中不同取向｛111｝γ惯习面成束形成，而后在冷却过程中转变为层片团细小的γ／α2全层片组织.

病理试验室细小质嫩穿刺组织行脱水处理的方法及探讨

目的细小质嫩穿刺组织应用脱水、透明、浸蜡处理,其处理方法改进后组织有韧性,不易碎裂,石蜡包埋组织后能切出完整组织,易于镜下观察。方法收到组织后,立即置于中性缓冲固定液中固定,再进行脱水、透明、浸蜡、包埋、切片、染色。结果组织在制片过程中经过改进方法处理后,保证了组织结构的完整,使组织无过度收缩、变硬,切片时无碎裂,着色优质且能准确表达。结论细小质嫩穿刺组织脱水、透明、浸蜡的处理方法改进后,组织结构最大限度保持与活体组织结构相近,用石蜡包埋组织后,可切出组织结构完整的切片,同时易于切出超薄切片及连续切片,切片染色易着色,镜下观察组织细胞结构完整,细胞表达的效果明显优于未改进之前的效果。

双辊铸轧不锈钢薄带中细小晶粒组织的形成

为研究双辊铸轧薄带中各种组织的形成,在实验室的双辊铸机上进行704和1Cr18Ni9Ti奥氏体不锈钢薄带的铸轧实验.对铸轧薄带中所出现的各种细小晶粒组织进行分析,利用金属学及结晶热力学的理论结合有限元模拟计算所得结果对各种组织的形成条件和机制进行探讨.结果表明:双辊铸轧不锈钢可以得到2μm以下的表层激冷组织和2μm的细小枝晶组织,提高了材料表层的抗腐蚀能力;在铸轧薄带中不仅存在中心层的细小等轴晶粒,而且在枝晶区还存在由破碎的枝晶演变而来的较大等轴晶粒,对这些较大等轴晶粒的生成机制出了解释.

新型多相TiAl合金的β/B2相含量变化及其对拉伸性能的影响

以新型多相TiAl合金(Ti-43.5Al-6(Nb、Cr、Ta))的挤压态组织为研究对象,先通过热处理分析该合金中β/B2相、α/α2相和γ相平均含量随固溶温度和保温时间的演变规律,然后测试合金在三相区内不同β/B2相含量时的室温和高温(750℃和800℃)拉伸性能。结果表明:在1190~1350℃范围内,γ相含量随固溶温度的升高和保温时间的延长逐渐减少,在1270℃时,γ相完全消失;在1190~1350℃范围内,β/B2相含量随固溶温度的升高先减少后增加,随保温时间的延长逐渐减少,而层片团的含量和尺寸与β/B2相的含量变化负相关;在1230~1280℃范围内,β/B2相平均含量可控制在10%以下;在1250~1270℃范围内,延长保温时间可将β/B2相平均含量控制在0.5%以下;当合金处于三相区时,控制β/B2相平均含量约6%,可得到综合拉伸性能优异的均匀细小近层片组织,且该组织的室温抗拉强度超过1050 MPa、室温伸长率1.5%~2%,750℃抗拉强度超过950 MPa,800℃抗拉强度超过850 MPa。

大线能量低焊接裂纹敏感性钢的研究

综述了国内大型成套工程用钢中压力容器用钢的研究现状;并指出能极大提高焊接效率,而其热影响区(HAZ)组织均匀细小的大线能量低焊接裂纹敏感性钢的发展趋势及前景。

Granular cell tumor of colon:Report of a case and review of literature

Granular cell tumor (GCT) is uncommon in the colon and rectum.Here we report a case of GCT in the transverse colon.A 48-year-old male patient underwent a screening colonoscopy.A yellowish sessile lesion,about 4 mm in diameter,was found in the transverse colon.An endoscopic snare resection was performed without complication. Histological examination revealed the tumor consisted of plump neoplastic cells with abundant granular eosinophilic cytoplasm containing acidophilic periodic acid Schiff- positive,diastase-resistant granules.Immunohistochemical analysis showed the tumor cells expressed S-100 protein and neuron-specific enolase.Thus,the resected tumor was diagnosed as a GCT.Since GCTs are usually benign,endoscopic resection constitutes an easy and safe treatment. Colonoscopists should consider the possibility of GCT in the differential diagnosis of submucosal tumors of the colon.

Spatial organization of bacterial flora in normal and inflamed intestine: A fluorescence in situ hybridization study in mice

AIM: To studythe role of intestinal flora in inflammatory bowel disease (IBD).METHODS: The spatial organization of intestinal flora was investigated in normal mice and in two models of murine colitis using fluorescence in situ hybridization.RESULTS: The murine small intestine was nearly bacteriafree. The normal colonic flora was organized in three distinct compartments (crypt, interlaced, and fecal), each with different bacterial compositions. Crypt bacteria were present in the cecum and proximal colon. The fecal compartment was composed of homogeneously mixed bacterial groups that directly contacted the colonic wall in the cecum but were separated from the proximal colonic wall by a dense interlaced layer. Beginning in the middle colon, a mucus gap of growing thickness physically separated all intestinal bacteria from contact with the epithelium. Colonic inflammation was accompanied with a depletion of bacteria within the fecal compartment, a reduced surface area in which feces had direct contact with the colonic wall, increased thickness and spread of the mucus gap, and massive increases of bacterial concentrations in the crypt and interlaced compartments. Adhesive and infiltrative bacteria were observed in inflamed colon only, with dominant Bacteroides species.CONCLUSION: The proximal and distal colons are functionally different organs with respect to the intestinal flora, representing a bioreactor and a Segregation device.The highly organized structure of the colonic flora, its specific arrangement in different colonic segments, and its specialized response to inflammatory stimuli indicate that the intestinal flora is an innate part of host immunity that is under complex control.

The expression and significance of the multidrug resistance-related proteins P-gp, MRP and LRP in human non-small cell lung cancer tissues

Objective: To explore the expression and significance of the multidrug resistance-related proteins P-glycopro-tein (P-gp), multidrug resistance-related protein (MRP), lung resistance protein (LRP) in human non-small cell lung cancer (NSCLC) tissues and paratumor tissues. Methods: Immunohistochemistry (IHC) was used to examine the expression level of proteins P-gp, MRP and LRP in 43 samples of NSCLC and 15 samples of paratumor tissues. Results: The expression rates of P-gp, MRP and LRP in 43 tumor tissues were 74.42% (32/43), 67.44% (29/43) and 88.37% (38/43), respectively, while in 15 paratumor tissues were 13.33% (2/15), 20.00% (3/15) and 6.67% (1/15), respectively. There was significant difference in the expression of proteins (P-gp, MRP and LRP) between lung cancer tissues and paratumor tissues (P < 0.05). The expres-sion of proteins P-gp, LRP in lung adenocarcinoma were higher than that in other pathological carcinomas (P < 0.05). The expression of protein MRP was not related to pathological type, clinical stage and classification of histodifferentiation (P > 0.05). Conclusion: Multidrug resistance is more common in NSCLC. The proteins of P-gp, MRP and LRP participated in the formation of multidrug resistance in lung cancer. Detection of multidrug resistance-related proteins in lung cancer tissues may be useful to choice drugs.

Expression of caveolin-1 in clear cell renal cell carcinoma and its correlation with microvessel density

Objective:The aim of the study was to investigate the clinicopathologic significance of caveolin-1 expression in clear cell renal cell carcinoma (CCRCC) and its correlation with microvessel density (MVD).Methods:The expression of caveolin-1 was detected by the immunohistochemistry method,while the microvessel density was detected by the immunohistochemistry expression of CD34.Results:In the CCRCCs,the positive rate of caveolin-1 was 67.4%,the over expression of caveolin-1 was not related with sex and age,but related with clinicopathologic parameter,such as tumor sizes,clinical TMN stage,nuclear stage and survival time (P < 0.05).The MVD of positive caveolin-1 cases was significantly higher than that without caveolin-1 expression (P < 0.05).Conclusion:The expression of caveolin-1 is helpful in the prognostic evaluation of CCRCCs and it may be involved in the tumor angiogenesis.

Clinicopathological Significance of E-cadherin and PCNA Expression in Hunman Non-small Cell Lung Cancer

OBJECTIVE This study was designed to assess E-cadherin (E-cad)and proliferating cell nuclear antigen(PCNA)expression as well as their clinicopathological significance in hunman non- small cell lung cancers(NSCLCs).Possible molecular mechanisms of differentiation and metastasis of NSCLCs are discussed. METHODS Immunohistochemical and immunofluorescence double staining were performed to examine the expression of E-cad and PCNA in 68 primary NSCLCs cases. RESULTS The E-cad expression in squamous cell carcinomas and adenocarcinomas showed no significant difference.E-cad expression had a positive correlation with the histological- differentiated grade.A significant difference of E-cad expression was found between metastatic and non-metastatic groups.PCNA expression in squamous cell carcinomas and adenocarcinomas showed no significant difference.The PCNA expression had a reverse correlation with the histological-differentiated grade.A significant difference of PCNA expression was found between metastatic and non-metastatic groups.The E-cad and PCNA expression presented a reverse correlation. CONCLUSION E-cad expression is not associated with the histological type of NSCLC,but is associated with differentiation and metastasis of the cancer.Down-regulation of E-cad expression affects the proliferation of cancer cells.Conjoint analysis of E-cad and PCNA expression is a good way to evaluate tumor biological behavior.

Glutamine depletion induces murine neonatal melena with increased apoptosis of the intestinal epithelium

AIM:To investigate the possible biological outcome and effect of glutamine depletion in neonatal mice and rodent intestinal epithelial cells.METHODS:We developed three kinds of artificial milk with different amounts of glutamine;Complete amino acid milk (CAM),which is based on maternal mouse milk,glutamine-depleted milk (GDM),and glutaminerich milk (GRM).GRM contains three-fold more glutamine than CAM.Eighty-seven newborn mice were divided into three groups and were fed with either of CAM,GDM,or GRM via a recently improved nipple-bottle system for seven days.After the feeding period,the mice were subjected to macroscopic and microscopic observations by immunohistochemistry for 5-bromo-2'deoxyuridine (BrdU) and Ki-67 as markers of cell proliferation,and for cleaved-caspase-3 as a marker of apoptosis.Moreover,IEC6 rat intestinal epithelial cells were cultured in different concentrations of glutamine and were subject to a 4-[3-(4-iodophenyl)-2-(4-nitrophenyl)2H-5-tetrazolio]-1,3-benzene disulfonate cell proliferation assay,flow cytometry,and western blotting to examine the biological effect of glutamine on cell growth and apoptosis.RESULTS:During the feeding period,we found colonic hemorrhage in six of 28 GDM-fed mice (21.4%),but not in the GRM-fed mice,with no differences in body weight gain between each group.Microscopic examination showed destruction of microvilli and the disappearance of glycocalyx of the intestinal wall in the colon epithelial tissues taken from GDM-fed mice.Intake of GDM reduced BrdU incorporation (the average percentage of BrdU-positive staining;GRM:13.8%,CAM:10.7%,GDM:1.14%,GRM vs GDM:P < 0.001,CAM vs GDM:P < 0.001) and Ki-67 labeling index (the average percentage of Ki67-positive staining;GRM:24.5%,CAM:22.4% GDM:19.4%,GRM vs GDM:P=0.001,CAM vs GDM:P =0.049),suggesting that glutamine depletion inhibited cell proliferation of intestinal epithelial cells.Glutamine deprivation further caused the deformation of the nuclear membrane and the plasma membrane,accompanied by chromatin degeneration and an absence of fat droplets from the colonic epithelia,indicating that the cells underwent apoptosis.Moreover,immunohistochemical analysis revealed the appearance of cleaved caspase-3 in colonic epithelial cells of GDM-fed mice.Finally,when IEC6 rat intestinal epithelial cells were cultured without glutamine,cell proliferation was significantly suppressed after 24 h (relative cell growth;4 mmol/L:100.0% ± 36.1%,0 mmol/L:25.3% ± 25.0%,P < 0.05),with severe cellular damage.The cells underwent apoptosis,accompanied by increased cell population in sub-G0 phase (4 mmol/L:1.68%,0.4 mmol/L:1.35%,0 mmol/L:5.21%),where dying cells are supposed to accumulate.CONCLUSION:Glutamine is an important alimentary component for the maintenance of intestinal mucosa.Glutamine deprivation can cause instability of the intestinal epithelial alignment by increased apoptosis.

Effect and mechanism of (125)~I radioactive particles interposed radiotherapy between organizations on lung cancer

Objective:The aim of this study was to evaluate effect and mechanism of 125I radioactive particles interposed radiotherapy between organizations on lung cancer.Methods:Fourteen cases of patients diagnosed with non-small cell lung cancer(NSCLC),the use of the B-,CT-guided,according to preoperative imaging and treatment planning system(TPS) program for radioactive particles interposed 125I interstitial radiotherapy.Results:All patients were successfully 125I interstitial radioactive particles interposed radiotherapy.Postoperative local complete tumor remission in 9 cases,partial remission in 5 cases,the efficiency of 100%.No case of serious complications.After 3 to 4 weeks of chemotherapy after 11 cases.4 cases of lung cancer with bone metastases,pain completely disappeared after treatment.Up to now,five cases have died due to tumor progression,survival time of 12 to 16 months.Nine cases still under follow-up observation and treatment.Conclusion:125 I radioactive particles interposed radiotherapy between organizations of lung cancer,simple operation,trauma,fewer complications,conformal high,high local tumor dose,efficacy,and is a supplement of modern radiotherapy techniques for the treatment of lung cancer provides a comprehensive line of the method of effective.

变形TiAl合金全层片组织细化及拉伸性能

针对名义成分为Ti-46Al-3.8(V,Cr,Ni)(at%)的挤压TiAl合金,研究了热处理工艺对高温时β相含量、形貌的影响,利用高温时β相对α相晶粒的钉扎作用获得了层片团尺寸均匀、细小的全层片组织,测试了具有该组织合金的拉伸性能。结果表明,在1320～1370℃范围内,随保温温度的升高,β相含量逐渐增加,使得合金的晶粒尺寸逐渐减小。实验合金经1340℃/5min/AC热处理后可以获得层片团(尺寸平均为65μm),B2相弥散分布的全层片组织。该组织的室温及高温拉伸性能均较好。少量B2相对合金的室温塑性无不利影响,对合金的高温强度可能有一定贡献。

快速凝固硅铝合金材料的组织与性能

针对电子信息工业对新型结构功能一体化电子封装材料的应用需求,采用喷射成形与热压致密化相结合的方法制备高Si含量(质量分数为50%～70%Si)的系列Si-Al合金,并利用金相显微镜、扫描电镜、硬度测试仪、热膨胀仪等手段研究该材料的显微组织、力学性能和热物理性能。结果表明,喷射成形高硅铝合金的沉积态显微组织细小弥散,初生硅呈不规则形状,均匀弥散地分布在铝基体中;对沉积坯件进行适当的热压致密化处理可以有效地消减喷射成形制坯工艺过程中所形成的疏松和孔洞,提高材料的致密度。经热压致密化处理的喷射成形高硅铝合金材料具有优越的热物理性能以及良好的力学性能,是一种综合性能优越的结构功能一体化电子封装材料。

钛合金表面激光熔覆钴基复合涂层的组织和性能

利用横流CO2激光器在钛合金表面制备出原位自生TiB体系陶瓷颗粒增强Co基复合材料涂层,以改善常规材料表面综合使用性能。采用XRD、SEM、EPMA等手段对复合涂层进行研究。结果表明:涂层中原位合成的TiB2和TiB陶瓷相均匀分布在γ-Co基合金涂层中。涂层内枝晶组织细小均匀,枝晶内和枝晶间存在明显的组织和成分差异。涂层显微硬度比基体显著提高,约为基体的3倍,同时耐磨性也得到显著改善。

Effect of volatile oil from Blumea Balsamifera(L.) DC. leaves on wound healing in mice

OBJECTIVE: To assess the effectiveness of violateoil from Blumea Balsamifera(L.) DC. leaves(BB oil)on wound healing in mice.METHODS: Undiluted BB oil and its diluted solutions with olive oil to 1/5 and 1/10 to yield BB oil1/5and BB oil1/10 were applied to the wounded skin before wound healing conditions were assessed by healing rate, histopathology, and contents of collagen, hydroxyproline, and Neuropeptide Substance P(SP). All above results were compared with the efficacies of the control, pure olive oil, basic fibroblast growth factor(BFGF), and cream of Jing Wan Hong(JWH).RESULTS: BB oil1/5and BB oil1/10 improved wound contraction and closure. Histopathology study further confirmed a desirable histological organization of wound tissues. BB oil1/5and BB oil1/10 reduced the number of inflammatory cells, increased wound-healing rates, and significantly increased the hydroxyproline content. Both BB oil1/5and BB oil1/10 improved formation of collagen, and reduced the frequency of fibroblasts. Moreover, BB oil1/5and BB oil1/10 markedly promoted SP expression. However, undiluted BB oil may induce skin thickening and hardening, inhibite collagen synthesis and delay complete skin wound healing.CONCLUSION: The BB oil1/5and BB oil1/10 promoted capillary regeneration, blood circulation, collagen deposition, granular tissue formation, epithelial deposition, and wound contraction. The mechanism underlying the action might be related to induction of SP secretion, and the proliferation and differentiation of mesenchymal cells.