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991.
Establishing orthotopic transplanted models of human pancreatic cancer in nude mice and study on their biological properties] 总被引:1,自引:1,他引:0
Two cell lines of human pancreatic cancer have been established, which can be successfully transplanted into pancreas of nude mice, the first of this kind of cell lines in China. Fresh specimens human of pancreatic cancer taken surgically were transplanted in the pancreas of pure line BALB/C-nu/nu nude mice. The transplanted tumours grew and reproduced successfully, and were named PINMP-1 and PINMP-2, respectively. So far, 9 generations of PINMP-1 and 6 generations of PINMP-2 were obtained. Their biological properties, ways of invasion and metastasis and morphological characteristics under light and electron microscope were studied. The results showed a 95%-100% transplanting success rate, with the success rate of transplanting from tissues revivified from the liquid nitrogen preservation being 100%. Both of the lines could produce large amount of CEA, and chromosome analysis confirmed that they had retained a karyotype of the human cancer cells. In nude mice transplanted with the tumours, metastasis could be found in the lymph nodes, lungs and livers. Metastasis via lymphatic channels and blood vessels were also demonstrated. The pathological and ultrastructural examination confirmed that the transplanted tumours had identical characteristics as their donor tumours. The transplanted cells grew independently in the pancreas of the nude mice, making a better model for study on tumour invasion and metastasis than subcutaneously transplanted tumours. This indicated that the microenvironment in the transplantation site had certain influence on the biological behavior of the transplanted tumours. The models could be used in the study on the invasion, metastasis and experimental therapy of pancreatic carcinomas. 相似文献
992.
993.
Z N Kain M R Chinoy M T Antonio-Santiago R N Marchitelli E M Scarpelli 《Pediatric research》1991,29(6):534-537
Because of cocaine's possible effect on the incidence of respiratory distress syndrome in offspring of cocaine-addicted mothers, we have studied the effects of maternal exposure to cocaine on the functional anatomy of fetal rabbit lungs. Pregnant dams were injected s.c. daily with either cocaine (18 mg/kg) or an equal volume of 0.9% NaCl at 24, 25, and 26 d gestation. Cocaine metabolites were confirmed both in urine of treated dams and in fetal amniotic fluid. Serum cortisol levels were higher in treated dams than in controls. Fetuses were delivered through hysterotomy at 27 d. Tracheas were cannulated and a volume-pressure diagram was obtained during initial lung inflation-deflation. Volume was measured for 2 min at each pressure (P) increment of 5 cm H2O. Body weights and dry lung weights were comparable between the two groups. In contrast, cocaine-exposed lungs differed from controls as follows: 1) wet lung weights were lower (0.79 versus 0.89 g, p less than 0.02); 2) opening pressure was lower (P25 versus P35); 3) volume (mL/kg) was higher in treated animals at each pressure step (p less than 0.05); 4) end-deflation volume at P0 was higher (30.4 versus 0.8 mL/kg, p less than 0.001); and 5) bubbles released from saccules by micropuncture, which were stable by Pattle's criteria, had estimated surface tension near zero (controls produced no stable bubbles). Light micrographs of cocaine-exposed fetuses revealed more secondary septa and thinner septal walls than controls.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
994.
Correlation between serological and mucosal inflammatory responses to Helicobacter pylori.
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G I Pérez-Pérez W R Brown T L Cover B E Dunn P Cao M J Blaser 《Clinical and Vaccine Immunology : CVI》1994,1(3):325-329
In 82 patients who underwent gastroduodenoscopy, acute and chronic gastric mucosal inflammation was scored for severity, and systemic humoral immune responses to Helicobacter pylori antigens were assessed by enzyme-linked immunosorbent assays. On the basis of culture, gastric histology, and serologic evaluation, 33 patients were classified as H. pylori infected and 36 were classified as uninfected. Thirteen patients had negative cultures and stains but were seropositive and were analyzed separately from the other two groups. Specific serum immunoglobulin G (IgG) subclass responses to H. pylori whole-cell antigens and specific IgG responses to the 54-kDa heat shock protein homolog (Hp54K) and vacuolating cytotoxin were significantly greater in infected than in uninfected patients as were specific IgA responses to whole-cell antigens and cytotoxin (P < 0.001). Among the H. pylori-infected persons, serum IgG responses to Hp54K and to the vacuolating cytotoxin were correlated with acute mucosal inflammatory scores. In contrast, serum IgA responses to whole-cell sonicate and to vacuolating cytotoxin were inversely related to chronic inflammatory scores. By multivariant regression analysis, only specific serum IgG responses to Hp54K correlated with severity of inflammation (both acute and chronic; P < 0.001); these responses may be markers of inflammation or these antibodies could play a direct role in the pathogenesis of H. pylori-induced inflammation. 相似文献
995.
Nonoxynol-9 and the reduction of HIV transmission in women. 总被引:1,自引:0,他引:1
996.
枸杞多糖对运动性骨骼肌疲劳恢复的细胞定量化学分析和电镜观察 总被引:7,自引:0,他引:7
通过小鼠实验,用枸杞多糖解除运动性骨骼肌疲劳,以显微分光光度计进行琥珀酸脱氢酶(SDH)和糖原的定性定量分析,并于透射电镜下观察超微结构的变化。结果显示,运动疲劳(B)组糖原含量明显降低,各类肌纤维与对照(A)组比较P<0.001。SDH活性增加,各类肌纤维与A组比较P<0.001。服用枸杞多糖(C)组糖原含量增加,各类肌纤维与A组之较P<0.001;与B组比较P<0.001;SDH反应较B组更深,各类肌纤维与A组比较P<0.001,若与B组比较,则其中Ⅰ(慢肌)型和Ⅱ(中间肌)型P<0.001,而Ⅱ(快肌)型则P>0.05。超微结构显示,B组线粒体增多且体积明显增大,呈肿胀状态,C组全无此类改变,提示服用枸杞多糖后可解除疲劳,其中以Ⅰ(慢肌)型肌纤维效果尤佳。 相似文献
997.
998.
Gluing of sterile abdominal benign cyst walls with tissue adhesives (Tissucol) (preliminary report)]
The authors, endeavouring to stick the walls of percutaneously emptied cysts together had applied the two-component Tissucol fibrin glue in the treatment of abdominal and thoracic cysts. Their ten cases, however, may be considered only as preliminary experiences. It seems that the method can be recommended for an attempt to cease these formations in a fast and simple way. Nevertheless, this method must not be the subject of treatment in infected and malignant fluid collections, but seems successful in pancreatic pseudocysts, in spite of their higher proteolytic activity. 相似文献
999.
On the basis of analysis of 128 cases of serological incompatibility it was found that antibodies to Rh in titres of 1/8 or less constituted a good prognostic factor, and without evidence of fetal distress in USG examination this was not an indication to treatment undertaking. If the titre is from 1/16 to 1/128 the prognosis is worse and the degree of fetal haemolytic disease risk may be estimated on the basis of USG and Liley's zone. The prognosis is very bad in case of titre exceeding 1/128 and high Liley's zone, and without effective treatment of haemolytic disease in fetal life only few fetuses survive. 相似文献
1000.