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71.
72.
Summary: We have developed a novel experimental model of cancer immunity in the frog, Xenopus , which may provide a useful alternative to murine tumor models and a way to assess whether the control of tumor development is a fundamental function of the immune system of vertebrates. In Xenoptis , tumor immunity can be studied in two developmentally distinct immune systems. The larval immune system reflects characteristics of an ancestral system that appears to function without classical MHC class I antigen presentation and an efficient effector mechanism. The adult system appears more highly evolved in that it is remarkably similar to that of mammals and is able to generate a potent antitumor response. This amphibian model also provides a unique system with which to investigate a postulated role of heat shock proteins as components of an ancestral system of antigen presentation and/or immune surveillance that predates the antigen presentation pathway that exclusively involves MHC molecules. 相似文献
73.
Although it is chemically a classical tricyclic antidepressant agent, trimipramine shows atypical pharmacological properties. Its well-documented antidepressant action cannot be explained by noradrenaline or serotonin reuptake inhibition or by a down-regulation of β-adrenoceptors. Furthermore, its receptor affinity profile resembles more that of clozapine, a neuroleptic drug, than that of tricyclic antidepressants. Trimipramine does not reduce, but rather increases, rapid eye movement sleep. It stimulates nocturnal prolactin secretion and inhibits nocturnal cortisol secretion, and may act at the level of the hypothalamus on corticotropin-releasing hormone secretion. Trimipramine is of particular value in depressed patients with insomnia, and it has been shown to be effective in the therapy of primary insomnia. As the pharmacological profile indicates, and an open clinical study has shown, trimipramine might also be active as an antipsychotic. The drug is both a tool for increasing our understanding of depression and a potential therapy for several psychiatric disorders. 相似文献
74.
Jean-Luc Garrigue Philippe Catroux Jacques Leclaire 《Clinical reviews in allergy & immunology》1995,13(3):189-200
Conclusion The search for a link between cellular and molecular events involved in delayed-type CHS reactions and the early molecular
activation of xenobiotics is a new field of research. It should largely contribute to the debate on the best way forward for
predictive toxicology in general. 相似文献
75.
As a result of modern therapeutic and technological advances, the surgeon has the ability to salvage even the most severely injured lower limbs. However, the success of replantation nowadays is no longer measured simply on the basis of restoration of viability but also on functional outcome compared with primary amputation with early prosthetic fitting, the risk to the patient during and after replantation and the overall time of treatment which should not exceed 2 years. Although every major limb replantation has to be considered individually, the decision-making process for reconstruction (replantation/revascularisation) versus amputation with subsequent early prosthetic fitting should be determined by objective criteria. Based on personal experience and an extensive literature search, an algorithm for treatment of amputation or amputation-like injuries to the lower leg has been developed and tested in a clinical study. A 100% viability success rate was achieved. There was not only a significant increase in the percentage of “functional extremities” but also a doubling in grade I results. Moreover, there was a 50% reduction in patients presenting a “non-functional extremity”, and no patient required a secondary re-amputation. The replantation risk (e.g., risk of severe systemic disturbance during and/or after replantation) was about 16.6% (2/12) in our study. There was a significant decrease in the postoperative complication rate and no patient died during or after replantation. Based on our experience, if reconstruction in subtotal or total lower leg amputation is done for a well-selected patient group, good functional results with a reasonable replantation risk and a reasonable time for social re-integration can be achieved. © 1995 Wiley-Liss, Inc. 相似文献
76.
D J Bergin C D McCord T Berger H Friedberg W Waterhouse 《The British journal of ophthalmology》1988,72(11):863-867
Blepharochalasis is an uncommon disorder distinguished by recurrent episodes of eyelid oedema in young patients. A hypertrophic form, manifested as fat herniation, and an atrophic form, manifested as fat atrophy, have been described. Ptosis with excellent levator function, laxity of the lateral canthal structures with rounding of the lateral canthal angle, nasal fat pad atrophy, and redundant eyelid skin develop after many episodes of eyelid swelling. Fine wrinkling, atrophy, and telangiectasias characterise the excess eyelid skin. We describe four cases of this syndrome in which external levator aponeurosis tuck, blepharoplasty, lateral canthoplasty, and dermis fat grafts were used to correct atrophic blepharochalasis after the syndrome had run its course. 相似文献
77.
78.
Mentosternal contractures still represent a surgical challenge due to their prominent position. They require early operative treatment for both function and aesthetic reasons. Careful clinical examination of scar position and traction forces, both at rest and when functioning, in addition to proper evaluation of the surrounding soft tissue are mandatory for precise preoperative planning of the required reconstruction. In general, the technically most feasible operation is favored if the functional and aesthetic results are good and postoperative risk for recurrence is low. Between 1987 and 1994, 21 patients with cervical, mentosternal, and mentothoracic contractures were operated upon. Eight patients were reconstructed with local flaps and 13 with microvascular free flaps. 相似文献
79.
The study was performed to assess the ethiological role of bile in acute pancreatitis provoked by closed duodenal loop in rat. In group I a closed duodenal loop was created by method of Nevalainen. A similar operation was performed in group II, but the common pancreatico-biliary duct was ligated just under the liver. In the control group (group C) only the mobilization of duodenum was performed. After 24 hours the mortality rate was 20% in group I, but 0% in group II and C. The amount of ascitic fluid showed significant elevation in group I versus II and group C, and in group II as compared to group C, too. The serum amylase was significantly higher in group I than group II and group C, and in group II was also higher as compared to group C. Serum total protein differed significantly between all groups, while albumin and total calcium were significantly lower in group I than group II, but group II was only slightly reduced versus group C. Histology showed no differences between groups I and II, but both differed significantly from group C. In conclusion bile seems to be an aggressive factor in pathogenesis of acute pancreatitis induced by closed duodenal loop in rat, but other factors may play more important roles. 相似文献
80.
J Leveque D Berger P Poulain J Blanchot J Y Grall 《Revue fran?aise de gynécologie et d'obstétrique》1991,86(10):601-608
The authors use two personal cases to review the etiological circumstances, pathology and clinical and paraclinical manifestations, stressing in particular the current value of diagnostic and therapeutic hysteroscopy. Advice is given concerning prevention and treatment. 相似文献