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Histopathologic and ultrastructural correlates of tumor growth suppression by high energy shock waves 总被引:4,自引:0,他引:4
High energy shock waves (HESW) are cytotoxic to tumor cells as determined by vital staining and impaired ability of viable cells to form colonies in a clonogenic assay. In addition, direct exposure of tumor nodules to HESW results in suppression of tumor growth rate. In order to identify histopathologic and ultrastructural correlates of these observations, R3327AT-3 prostatic tumor cells were exposed to HESW in vitro and in vivo. Damage to cells in suspension was manifested by fragmentation of cells to form debris. At the ultrastructural level, mitochondria were swollen and contained distorted cristae following exposure of tumor cells to HESW. In vivo exposure of tumor nodules to HESW did not cause a distinct histopathologic or ultrastructural effect that could be qualitatively distinguished from spontaneously occurring cell death. Hemorrhage and necrosis were observed in muscle and fibroadipose tissue adjacent to tumor. The mechanism of HESW-induced cytotoxicity is not clear from our studies. Evidence of damage of normal tissues exposed in vivo and tumor cells in vitro is reflected in histomorphological changes. 相似文献
134.
Elastase in gingival crevicular fluid from smokers and non-smokers with chronic inflammatory periodontal disease 总被引:2,自引:0,他引:2
OBJECTIVE: To compare elastase concentrations in gingival crevicular fluid (GCF) from individual sites of smokers and non-smokers.
MATERIALS AND METHODS: Twelve pairs of smokers and non-smokers with untreated, moderate to advanced chronic inflammatory periodontal disease were matched for gender, age, ethnicity and the clinical and radio-graphic extent of disease. Durapore filter strip samples were collected over 30 s from two mesiopalatal sites on upper left posterior teeth. Samples were analysed for: I) polymorphonuclear neutrophil leucocyte (PMNL) cell counts; 2) PMNL elastase-αI-antitrypsin complex in the GCF supernatant by ELISA; and 3) functional elastase, free or bound to α2-macroglobulin, estimated from activity against N-tert-butoxycarbonyI-alanyl-prolyl-nor-valylg-chlorothiobenzyl ester in supernatant and lysates of GCF PMNLs.
RESULTS: There were no differences in disease parameters between groups except that bleeding on probing was less extensive in smokers (P< 0.001). Cell counts and elastase content of crevicular PMNLs showed no differences between groups. Lower concentrations of elastase were found in GCF supernatants from smokers than non-smokers. This difference was observed for functional elastase (mean [s.d.] = 30.21 [17.60] against 73.77 [75.26] ng μI-1 , P <0.05) and elastase complexed with αl-antitrypsin (8.97 [6.54] ng μl-1 against 25.71 [22.07] ng μI-1 , P < 0.001).
CONCLUSIONS: Smokers have lower elastase concentrations in GCF than non-smokers. Further investigation is required to elucidate the underlying cause and its relationship with periodontal disease. 相似文献
MATERIALS AND METHODS: Twelve pairs of smokers and non-smokers with untreated, moderate to advanced chronic inflammatory periodontal disease were matched for gender, age, ethnicity and the clinical and radio-graphic extent of disease. Durapore filter strip samples were collected over 30 s from two mesiopalatal sites on upper left posterior teeth. Samples were analysed for: I) polymorphonuclear neutrophil leucocyte (PMNL) cell counts; 2) PMNL elastase-αI-antitrypsin complex in the GCF supernatant by ELISA; and 3) functional elastase, free or bound to α2-macroglobulin, estimated from activity against N-tert-butoxycarbonyI-alanyl-prolyl-nor-valylg-chlorothiobenzyl ester in supernatant and lysates of GCF PMNLs.
RESULTS: There were no differences in disease parameters between groups except that bleeding on probing was less extensive in smokers (P< 0.001). Cell counts and elastase content of crevicular PMNLs showed no differences between groups. Lower concentrations of elastase were found in GCF supernatants from smokers than non-smokers. This difference was observed for functional elastase (mean [s.d.] = 30.21 [17.60] against 73.77 [75.26] ng μI
CONCLUSIONS: Smokers have lower elastase concentrations in GCF than non-smokers. Further investigation is required to elucidate the underlying cause and its relationship with periodontal disease. 相似文献
135.
目的:采用新生牛皮提取胶原蛋白、制备生物医用胶原蛋白海绵,观察其生物学活性与细胞相容性。方法:实验于2006-05/2007-02在西北民族大学生命科学与工程学院生物工程与技术国家民委重点实验室完成。实验方法:①取出生24h内宰杀的新生尕里巴牛犊皮制备胶原蛋白海绵。②将新生牛皮胶原蛋白海绵与黑裘皮羔羊肾F3代成纤维细胞混悬液共培养,分别设胶原海绵材料组、阴性对照组(生理盐水)、阳性对照组(橡胶塞浸提液)。实验评估:①应用倒置相差显微镜观察细胞形态。②培养20,35d对细胞与胶原蛋白海绵共培养物进行AO染色观察细胞在胶原海绵中的增殖情况。③培养65d后制石蜡切片,行苏木精-伊红染色观察细胞在胶原海绵中的生长情况。结果:①细胞形态观察结果:阳性对照组细胞培养24h细胞圆缩,不贴壁,3d后全部死亡。胶原海绵材料组与阴性对照组细胞形态均正常,细胞贴壁生长良好。随着培养时间的延长,海绵孔隙逐渐变小,细胞数量增加,形态变小,海绵外观从柔软、混浊变得挺拔、透明。②细胞在胶原海绵中的增殖情况:吖啶橙-AO染色显示培养20,35d胶原海绵-羔羊肾成纤维细胞共培养物中有大量细胞存在,并且在胶原蛋白空隙中有大量细胞成团簇状生长。③细胞在胶原海绵中的生长情况:苏木精-伊红染色显示有大量蓝色细胞核和新生的红色胶原纤维。结论:制备的新生牛皮胶原蛋白海绵对岷县黑裘皮羔羊肾成纤维细胞有良好的生物相容性,无细胞毒性。 相似文献
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1临床资料1999-08/2004-08我科采用延迟小骨窗开颅手术治疗硬膜外血肿96(男75,女21)例,年龄13~18(平均35)岁.受伤原因车祸72例,坠落伤11例,打击伤13例.均于伤后72 h内就诊并经头颅CT确诊,表现头痛96例,呕吐21例,一侧肢体无力32例,偏身麻木23例,癫痫发作1例,原发昏迷92例,59例≤30 min,33例为30~120 min,头痛进行性加重36例.就诊时GCS记分10~12分15例,13~15分81例,运动性失语2例,混合性失语3例.CT示血肿位于额顶叶12例,额叶32例,颞叶5例,顶枕叶8例,颞顶后39例(1例合并对侧脑内血肿,5例合并额颞叶脑挫裂伤).血肿量30~80mL.入院后3~15 d内先给予脱水剂、激素、止血剂、抗生素、脑活性药物、镇痛剂等对症处理保守治疗. 相似文献
138.
Baker LL; Hajek PC; Burkhard TK; Dicapua L; Landa HM; Leopold GR; Hesselink JR; Mattrey RF 《Radiology》1987,163(1):93-98
The utility of high-resolution magnetic resonance (MR) imaging in studying a variety of intratesticular and extratesticular pathologic conditions was assessed. The high magnetic signal intensity of the testis provided an excellent background for visualization of intratesticular abnormalities. Except for old blood, all intratesticular processes were less intense than testis, especially on T2-weighted images. The visualization of the tunica albuginea is a distinct advantage, allowing its assessment in cases of trauma or testicular tumors. Epididymal and spermatic cord abnormalities were easily recognized. All pathologic conditions were best seen on T2-weighted images acquired in the coronal plane. Balanced images allowed for tissue characterization. 相似文献
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140.
R Berner RF Schumacher LB Zimmerhackl A Frankenschmidt M Brandis 《Acta paediatrica (Oslo, Norway : 1992)》1994,83(9):992-993
Extraintestinal manifestations of salmonellosis in paediatric patients are found predominantly in infants less than three months of age. Genital involvement is a rare complication. We present a short review of the literature and describe the case of a 10–week-old boy suffering from severe diarrhoea, who presented with a swelling of the right testicle after six days of illness. He underwent surgery on suspicion of testicular torsion, whereby orchitis was diagnosed. Salmonella enteritidis was cultured from the intraoperative swab. All cultures from blood, CSF and urine remained sterile. We conclude that orchitis must be taken into consideration as an extraintestinal complication of enteric salmonellosis and as a differential diagnosis of tcsticular torsion. In addition, we wish to emphasize that any infant less than three months of age with suspected or proven salmonellosis, should receive early antibiotic treatment. 相似文献