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OBJECTIVE: We aimed to demonstrate the time-dependent ultrastructural changes in pneumocyte type II cells following brain injury, and to propose an electron microscopic scoring model for the damage. METHODS: Forty Wistar-Albino female rats weighing 170-200 g were used. The rats were allocated into five groups. The first group was the control and the second was the craniotomy without trauma. The others were trauma groups. Weight-drop method was used for achieving head trauma. Samples were obtained from the right and left pulmonary lobes at 2-, 8-, and 24-h intervals after transcardiac perfusion. An electron microscopic scoring model was used to reveal the changes. RESULTS: There were no ultrastructural pathological findings pointing to lung injury in any rat of the control groups. There was intense intracellular oedema in type II pneumocyte and interstitial oedema in the adjacent tissue in trauma groups. Oedema in mitochondria and dilatation in both smooth endoplasmic reticulum and Golgi apparatus was more evident in the 8- and 24-h trauma groups. The chromatin dispersion was disintegrated in the nucleus in all trauma groups. Scores of all trauma groups were significantly different from the controls (P<0.05). All trauma groups were different from each other at significant levels (P<0.05 for each trauma groups). CONCLUSIONS: The data suggested that ultrastructural damage is obvious at 2 h and deteriorates with time. The electron microscopic scoring model worked well in depicting the traumatic changes, which were supported by lipid peroxidation. Further experiments are needed to determine the exact outcome after brain death model.  相似文献   
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The modulation of drug metabolising enzymes by Masheri extract (ME) and Benzo(a)Pyrene [B(a)P] was studied in male Sprague Dawley rats fed different dietary protein levels. Two groups of 21 days old male Sprague Dawley rats were put on a high protein diet (SHP) with 20% Casein, and a low protein diet (SLP) with 3% Casein semisynthetic based diets for 12 weeks. The SLP fed animals showed lower basal levels of the Phase I activating enzymes viz. Cytochrome P450, Benzo(a)Pyrene hydroxylase, Benzphetamine demethylase and Phase II glutathione detoxification system viz. Glutathione (GSH) and Glutathione-S-transferase. ME and B(a)P treatment significantly depleted the glutathione detoxification system in the SLP group whereas an opposite effect was observed in the SHP group. Interstingly, ME and B(a)P treated rats in the SLP group showed a higher percent increase in the hepatic and pulmonary Phase I enzyme activities than those observed in the treated ME/B(a)P treated SHP rats. Furthermore, both ME and B(a)P significantly decreased the hepatic pool of vitamin A while a concomittant increase in that of vitamin C was observed.  相似文献   
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Radius, ulna, short bones (RUS), carpal (CARP) bone age (BA), tibial corticodiaphyseal (C/D) ratio and trabecular aspect were assessed in 19 children with steroid dependent nephrotic syndrome and 15 age matched healthy children. Both RUS and CARP BA were significantly lower than in the controls. Trabecular aspect and tibial C/D ratio did not show any statistical significance. There was a positive correlation between HSDS and RUS BA delay (r=−0.476, p<0.05); CARP BA delay and RUS BA delay (r=0.563, p<0.01) and RUS BA and CARP BA (r=0.891, p<0.001). In conclusion, RUS and CARP BA are both retarded and positively correlated in steroid dependent nephrotic children.  相似文献   
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Metastatic carcinoma to the testis is very rare. Metastasis of prostate adenocarcinoma to testis was detected incidentally after bilateral orchiectomy for hormonal management of metastatic prostate carcinoma. The metastatic lesion was not identified in physical examination or in macroscopic dissection of the testis after surgery. Microscopy revealed an adenocarcinoma which, given the history of the patient and a positive immunohistochemical stain for PSA, was identified as metastatic prostatic adenocarcinoma.  相似文献   
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Classical and anaplastic seminoma: difference in survival   总被引:1,自引:0,他引:1  
Bobba  VS; Mittal  BB; Hoover  SV; Kepka  A 《Radiology》1988,167(3):849-852
Classical and anaplastic seminoma are traditionally treated with radiation therapy and are said to have the same prognosis. A retrospective study was undertaken of 90 seminoma patients treated with radiation therapy between 1961 and 1985. The classical group consisted of 71 patients of whom 50 had stage I and 21 had stage II disease. The anaplastic group consisted of 19 patients of whom ten had stage I and nine had stage II disease. The median follow-up time was 64 months for the entire group. The 10-year relapse-free survival rate for the classical group was 94% and for the anaplastic group was 70% (P less than .05). For patients with classical stage I disease, the relapse-free actuarial survival rate was 98%; for patients with anaplastic stage I disease, it was 64% (P less than .02). For the classical stage II disease group, the relapse-free actuarial survival rate was 84% and for the anaplastic stage II disease group, 75% (P less than .70). Four patients in the classical group (6%) had relapses; of these, one patient had local recurrence of tumor, and three had distant metastases. In the anaplastic group, four patients (21%) had relapses; two patients had local recurrence of tumor, and two had distant metastases. Therefore the data suggest a difference in survival and relapse rates between classical and anaplastic seminoma.  相似文献   
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白玉杰  Seetha SV  Vamla B  高庆生 《医学争鸣》2003,24(20):1845-1848
目的:应用酵母双杂交方法筛选BRCA2相互作用蛋白编码基因,验证其相互作用并研究其功能联系。方法:以BRCA2基因3′端片段构建酵母双杂交质粒,筛选正常人乳腺上皮细胞cDNA库,获得编码相互作用蛋白的基因,采用免疫共沉淀、哺乳细胞双杂交和荧光酶测定等方法进一步验证蛋白间相互作用和功能联系.结果:采用酵母双杂交系统筛选,获得了多个编码BRCA2相互作用蛋白的基因,其中包括已知的FHL2蛋白;免疫共沉淀和哺乳动物细胞双杂交试验显示BRCA2和FHL2在体内特异性结合,并证实FHL2在体内形成同源二聚体;转录活性分析发现BRCA2与FHL2有协同转录激活作用。结论:发现BRCA2与FHL2蛋白间相互作用和功能联系,为BRCA2功能研究提供了新的方向。  相似文献   
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Serkan Yildirim 《Hand surgery》2005,10(2-3):323-326
The author reports an unusual case of neural fibrolipoma (lipofibromatous hamartoma) of the ulnar nerve in the hand. A 20-year-old man presented with a fusiform soft tissue mass in his right hand. Neurological examination was normal except to minimal pain on palpation. Surgical exploration revealed that ulnar nerve and its digital branches were infiltrated by fibrofatty tissues. Fibrofatty tissues were dissected and removed from the nerve by microsurgical technique. Histological examination confirmed the diagnosis as a lipofibromatous hamartoma of the nerve. The result of surgical debulking was satisfactory.  相似文献   
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