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41.
We wished to examine the role of transforming growth factor-beta (TGF- beta) in the regulation of human lymphoma cell growth. The RL cell line is an immunoglobulin M (IgM)+, IgD+ B lymphoma cell line, which does not constitutively express receptors for TGF-beta, and thus has lost the ability to respond to the inhibitory effects of TGF-beta. We demonstrate here that anti-Ig antibodies can efficiently upregulate the expression of TGF-beta receptors and promote sensitivity to growth inhibition by TGF-beta. Furthermore, because TGF-beta has been shown to function in late G1 of the cell cycle, we examined the ability of TGF- beta to modulate two tumor suppressor proteins known to be critical regulators of the G1/S transition, Rb and p53. Rb is a 105- to 110-kD phosphoprotein, which has been shown to maintain its growth suppressive function when it is found in the hypophosphorylated state. Wild-type p53 is a 53-kD phosphoprotein that appears to be important in preventing cell-cycle progression and promoting apoptosis in cells with DNA damage, whereas mutant p53 can overcome those functions. We show here that TGF-beta treatment of phorbol myristate acetate (PMA) or anti- Ig-activated RL cells results in growth inhibition through a dual effect on Rb and mutant p53. After TGF-beta treatment, we observe a predominance of Rb in the hypophosphorylated, growth suppressive form. In addition, we show a decrease in levels of mRNA and protein for mutant p53. We also show that, although these changes are sufficient to halt progression through the cell cycle, the cells do not appear to undergo extensive programmed cell death following 72 hours of TGF-beta treatment. Thus, although these lymphoma cells maintain the capacity to be negatively growth regulated by TGF-beta, the ability of TGF-beta to induce apoptosis must be independently controlled. 相似文献
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43.
D. Xanthakis M. Efthimiadis G. Papadakis N. Primikirios G. Chassapakis A. Roussaki N. Veranis A. Akrivakis C. J. Aligizakis 《Thorax》1972,27(5):517-528
Ninety-one cases of hydatid disease of the chest are reported. Eighty-eight were involving the lung, two the chest wall, and one the mediastinum. All the patients were treated surgically. Conservative operations (simple removal of the parasite and closure of the remaining cavity) were performed in 78 patients, 37 unruptured and 41 ruptured cysts. Late postoperative complications occurred in eleven. In 10 patients, recurrent haemoptysis was the main symptom due to residual cavity in four, bronchiectatic changes in two, and unknown aetiology in four. In one patient, recurrence of multiple cysts occurred in the affected lobe. Radical operations were carried out in 10 patients, including segmental resection in four and lobectomy in six. Conservative operations were performed in all cases of unruptured cysts, with the exception of a giant cyst in which resection was the operation of choice. For ruptured cysts with mild infection conservative operation was also performed. Resection was necessary only in patients with ruptured cysts with suppuration, bronchiectatic changes, and giant cysts replacing a whole lobe. There was no mortality. We believe that conservative operation is the treatment of choice for hydatid disease of the lung. Indications for resection are very limited. 相似文献
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45.
D S Xanthakis E Katsaras M Efthimiadis G Papadakis G Varouchakis C Aligizakis 《Thorax》1981,36(7):497-501
In the last 10 years we have operated on 33 cases of hydatid cyst of the liver with intrathoracic rupture. Twenty-one out of 33 cases ruptured into bronchi, in seven the rupture affected the pleural cavity, and in six simultaneous rupture into the bronchus and pleural cavity occurred. Laboratory tests were not carried out in all cases. The Casoni intradermal test was carried out in 23 cases and was positive in 18. A liver scan was performed in 10 and was positive in all. Conservative operations were carried out in 22 patients. In these the hepatic cavity was evacuated and separately drained. This was followed by suturing the diaphragmatic rupture and also closing the bronchial opening if present. Lung resections were performed in 11 out of 33 cases. In eight lobectomy was carried out and in three segmental resections. Resection was necessary when suppuration and bronchiectatic changes affected the lung. Ruptured cyst into the pleural cavity requires emergency thoracotomy after the anaphylactic shock is over. Removal of the parasite, re-expansion of the lung, and drainage of the pleural and hepatic cavities is necessary. Immediate and late complications occurred in 13 patients. In two postoperative haemorrhage occurred and in two postoperative empyema developed. Recurrent haemoptysis was seen in five, persistent bile fistula in one, and dissemination of hydatid cyst in three. In the remaining 20 cases there was no complication. Operative mortality was nil. 相似文献
46.
漫反射光谱法研究维生素C与片剂辅料的相互作用 总被引:2,自引:0,他引:2
漫反射是一束光射到一定厚度的不透明不光滑固体表面上,光被部分吸收和部分散射后,向各个方向的反射。反射光的分数称为反射率。测定反射率时一般与某种白色粉末(例如硫酸钡)相比较,测得的反射率为相对反射率。以相对反射率对波长作图所得的曲线称为漫反射光 相似文献
47.
J Efthimiadis 《Zentralblatt für Gyn?kologie》1975,97(21):1314-1316
Report of a case of hydropertubation after conception by a nulli-para, and deliverance of a healthy baby after full term pregnancy. The treatment was made by suspicion of closed fallopian tubes. 相似文献
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49.
Blood flow imaging with MR: spin-phase phenomena 总被引:2,自引:0,他引:2
Blood flow phenomena occurring when flow is within the magnetic resonance (MR) imaging plane were analyzed. In this situation, the signal intensity of vascular lumina is predominantly determined by spin-phase change phenomena, and section transition effects of moving spins can be neglected. In this paper, we develop the concepts of in-plane flow, with emphasis on the notion that the spatial variations in velocity and acceleration of blood, which mainly occur along vessel walls, are important determinants of intravascular signal loss in MR images. Flow patterns in the large mediastinal arteries were qualitatively and quantitatively analyzed in six healthy subjects and 14 patients with hemodynamic abnormalities using multiple electrocardiograph-gated image acquisition; ungated studies of 30 patients were analyzed for venous flow effects. Intraluminal signal was strongly dependent on the phase of the cardiac cycle and the echo number. Signal loss was found to occur along vessel walls, in vascular bends, and at bifurcations. 相似文献
50.