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1.
Presentations of acute appendicitis represent an ongoing challenge to surgeons. This case of retrocaecal perforated appendicitis presented clinically as a right lumbar abscess, with the concomitant new diagnosis of type 2 diabetes mellitus in a 66-year-old male. This case emphasises the importance of an abdominal CT scan in any patient presenting with unusual sepsis near the abdomen. 相似文献
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The effects of three chemically dissimilar calcium-blocking drugs were studied in experimental post-ischaemic renal failure, in the rat. After 45 min unilateral clamping and contralateral nephrectomy, post-ischaemic verapamil administration protected renal function (p less than 0.025), but flunarizine, either before or after ischaemia, was not beneficial. Following 60 min bilateral renal pedicle clamping, nifedipine administration was not beneficial. Verapamil was the only calcium-blocking drug which attenuated the post-ischaemic renal dysfunction. Calcium blockers which differ in their modes of action, differ in their ability to protect the kidney from ischaemia. 相似文献
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P A Giblin D J Leahy J Mennone P B Kavathas 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(5):1716-1720
The CD8 dimer interacts with the alpha 3 domain of
major histocompatibility complex class I molecules through two immunoglobulin
variable-like domains. In this study a crystal structure-informed mutational
analysis has been performed to identify amino acids in the CD8 alpha/alpha
homodimer that are likely to be involved in binding to class I. Several key
residues are situated on the top face of the dimer within loops analogous to the
complementarity-determining regions (CDRs) of immunoglobulin. In addition, other
important amino acids are located in the A and B beta-strands on the sides of
the dimer. The potential involvement of amino acids on both the top and the side
faces of the molecule is consistent with a bivalent model for the interaction
between a single CD8 alpha/alpha homodimer and two class I molecules and may
have important implications for signal transduction in class I-expressing cells.
This study also demonstrates a role for the positive surface potential of CD8 in
class I binding and complements previous work demonstrating the importance of a
negatively charged loop on the alpha 3 domain of class I for CD8
alpha/alpha-class I interaction. We propose a model whereby residues located on
the CDR-like loops of the CD8 homodimer interact with the alpha 3 domain of MHC
class I while amino acids on the side of the molecule containing the A and B
beta-strands contact the alpha 2 domain of class I. 相似文献
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Porter JD Merriam AP Leahy P Gong B Feuerman J Cheng G Khanna S 《Human molecular genetics》2004,13(3):257-269
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