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31.
We have assessed postoperative memory for lists of 10 neutralwords, presented by tape recording, in patients anaesthetizedby a standardized technique comprising thiopentone 5 mg kg–1,midazolam 0.07 mg kg–1, fentanyl 3 µg kg–1and 70% nitrous oxide in oxygen, using both free recall anda test in which the subject was asked to indicate the presentedwords from a larger list. Twenty-four patients were exposedto one of four tape-recorded lists of words and 24 were presentedwith a blank tape. There was no instance of free recall of presentedwords. Analysis of the responses in the implicit memory testrevealed no difference between the performance of the patientswho had been exposed to a word list and those who had not.  相似文献   
32.
The immune system protects us against foreign pathogens. However, if fine discrimination between self and non-self is not carried out properly, immunological attacks against self may be launched leading to autoimmune diseases, estimated to afflict up to 5% of the population. During the last decade it has become increasingly clear that regulatory CD4+CD25+ T cells (Treg cells) play an important role in the maintenance of immunological self-tolerance, and that this cell subset exerts its function by suppressing the proliferation or function of autoreactive T cells. Based on human and murine observations, this review presents a characterization of the phenotype and functions of the Treg cells in vitro and in vivo . An overview of the surface molecules associated with and the cytokines produced by the Treg cells is given and the origin, activation requirements and mode of action of the Treg cells are discussed. Finally, we address the possibility that Treg cells may play a central role in immune homeostasis, regulating not only autoimmune responses, but also immune responses toward foreign antigens.  相似文献   
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PROBLEM : To determine whether seminal fluid influences the expression of MHC class I antigens on the surface of basal trophoblast cells in the placenta of the rat. METHODS : Transfer of DA × DA embryos into a WF (allogeneic) or DA (syngeneic) recipient made pseudopregnant by hormonal treatment followed by mating with a vasectomized male (seminal fluid) or by mechanical stimulation (no seminal fluid). Antigen expression was determined by electron microscopic immunocytochemistry using the appropriate gold-labeled monoclonal antibodies. RESULTS : Seminal fluid did not affect the expression of MHC class I antigens on the surface of the basal trophoblast in either allogeneic or syngeneic matings. CONCLUSIONS : The suppression of the expression of paternal class I antigens on the surface of the basal trophoblast cells in allogeneic pregnancies most likely occurs at the genome level shortly after fertilization.  相似文献   
40.
Historically, the healing of tracheal or bronchial anastomoses has been the Achilles heel in pulmonary transplantation. In the past, steps taken to enhance healing of these structures and have allowed single-lung, double-lung, and heart-lung transplantation to be accomplished safely. This report presents a simplified technique for protection of the tracheal anastomosis in heart-lung and double-lung transplantation. This technique, wherein the pericardial fat pad from the right side is utilized to wrap the tracheal anastomosis, not only allows for excellent healing of the anastomosis but separates the aorta from the trachea. In 19 patients having heart-lung (N = 13) or double-lung (N = 6) transplantation there were no tracheal healing problems, dehiscence or stenosis found.  相似文献   
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