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1.
Chronic intestinal pseudo-obstruction (CIPO) is a rare pathological condition characterized by a marked derangement of gut propulsive motility mimicking mechanical obstruction, in the absence of any lesion occluding the gut lumen. This disease is often associated with a disabling and potentially life-threatening complications and is still too often unrecognized even in referral centres. As a result, patients receive neither appropriate care nor recognition of their severe health condition. Medical and surgical therapies are often unsatisfactory and long-term outcome turns out to be poor in the vast majority of cases. This article focuses on the main clinical features, the management and long-term outcome of patients affected by CIPO, with particular emphasis on those aspects which remain a matter of debate.  相似文献   
2.
Post-traumatic facial palsies are generally observed after a transverse, longitudinal or comminuted fracture of the pars petrosa. Occasionally, the fracture does not involve the Fallopian aqueduct and another mechanism must be sought. The authors present a case of facial palsy that occurred after a Le Fort's fracture of the base of the skull, not involving the Fallopian aqueduct on the CT scan. This was confirmed by surgical exploration. The authors recall the possibility of a facial palsy through the stretching of the nerve by the petrosal nerve.  相似文献   
3.
Summary.  Monoclonal antibodies Ds-1 and Ds-2 specifically labelling dog sperm acrosome were prepared by immunization of mice with acetic acid extracts of dog spermatozoa. Electron microscopy and indirect immunofluorescence localized the site of Ds-1 and Ds-2 proteins inside the acrosomal vesicle. Ds-1 antibody detected 55, 76, 115, 120 and 190kDa proteins under non-reducing conditions, and 73 kDa and 54 kDa proteins after reduction (p73/Ds-1 and p54/Ds-1). 92 kDa and 40 kDa proteins recognized by Ds-2 (p92/Ds-2 and p40/Ds-2) migrated at > 200 kDa in the absence of reducing agent. In vivo , p73/Ds-1 and p54/Ds-1 are therefore likely to be present both in free and complexed form, while all of p92/Ds-2 and p40/Ds-2 form disulfide-bonded complexes. Decrease in the rate of acrosomes stained with Ds-1 and Ds-2 was correlated with the progress of capacitation resulting in the increased rate of spontaneous acrosome reactions, as suggested by a dramatic effect of A23187. Monoclonal antibody to boar acrosin (ACR-2) recognized dog sperm acrosin homologue. A higher rate of ACR-2-negative spermatozoa was observed after capacitation and A23187 treatment compared to Ds-1 and Ds-2, indicating that proteins recognized by Ds-1 and Ds-2 are localized in a specific compartment of acrosome, distinct from acrosin and possibly representing fraction of acrosomal matrix.  相似文献   
4.
PURPOSE: Adhesion formation in osteoarthritis (OA) of the temporomandibular joint (TMJ) typically results in a sustained limitation of joint movement. We propose the hypothesis that free-radical-mediated crosslinking of proteins underlies this adhesion formation in affected joints. Free radicals may cause oxidative modification of proteins, creating an opportunity for the formation of intramolecular and intermolecular crosslinks via covalent bonds. This may stabilize protein aggregates, rendering them more resistant to degradation. In this study, the free-radical-mediated crosslinking of model proteins (fibrinogen and fibronectin) was investigated to test our hypothesis that free radicals contribute to adhesion formation via this mechanism in OA of the TMJ. MATERIALS AND METHODS: Physiological clot formation of fibrinogen by thrombin and free-radical-induced crosslinking of fibrinogen and of fibronectin were analyzed using spectrophotometric turbidity measurements, light-scattering techniques, polyacrylamide gel electrophoresis (PAGE), and rotary shadowing. RESULTS: Fibrinogen was shown to aggregate after free radical treatment, as detected using turbidity measurements and light-scattering techniques. Using PAGE, fibrinogen as well as fibronectin was shown to degrade under low oxidative stress. Under high oxidative stress, however, fragments from both proteins were found to be covalently crosslinked, resulting in high-molecular-weight protein aggregates. The aggregation was shown to be at random with rotary shadowing. CONCLUSION: The study shows that high oxidative stress contributes to the formation of crosslinked proteins that may serve as an initial scaffolding for the development of adhesions frequently seen in OA of the TMJ.  相似文献   
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Sumatriptan, a 5-hydroxytryptamine(1D) (5-HT(1D))-receptor agonist used in the treatment in migraine, inhibits gastric motility via the enteric nervous system. As no studies have reported enteric neuronal 5-HT(1D) receptors, we used conventional intracellular recordings to characterize the actions of sumatriptan on 145 guinea-pig antral myenteric neurones. In 24 of 29 neurones with a 5-HT(1P) receptor-mediated depolarizing response to 5-HT, application of sumatriptan caused a dose-dependent depolarization, accompanied by increased membrane resistance and enhanced excitability. Depolarizing responses to sumatriptan occurred both in cholinergic and in nitrergic neurones. Sumatriptan did not mimic the 5-HT(3) receptor-mediated fast-depolarizing responses or 5-HT(1A) receptor-mediated inhibitory responses to 5-HT. Sumatriptan had no effect on neurones not responding to 5-HT. The depolarizing response to sumatriptan was inhibited by renzapride, but not by 5-HT(1-7) receptor antagonists. We conclude that sumatriptan behaves as an agonist at the 5-HT(1P) receptor on myenteric neurones in the guinea-pig gastric antrum. The actions of sumatriptan on gastric motility seem to be attributable to a direct action on enteric neurones.  相似文献   
8.
We describe our findings in an ultrastructural study of the endolymphatic sac of the mongolian gerbil. In conjunction with its specific renal physiology, enabling this animal to withstand long-term water deprivation, we have used our findings to hypothesize the existence of a local monitoring system within the endolymphatic space. The presence of elastic tissue in the subepithelial space of the endolymphatic sac could explain the mechanism through which this structure equilibrates endolymphatic pressure changes. Finally, we propose that a secretion of water-retaining macromolecules may act through osmotic forces to modulate inner ear fluid.  相似文献   
9.
The authors have taken an interest in isolated vertiginous symptoms observed from free diving patients. In order to achieve a current bibliographic synthesis, they resume, on basis of 6 cases, the basic principles of the physics theories and the etiopathogenic mechanisms. They try so to help in the understanding of the vestibular clinical signs observed in this successful sport.  相似文献   
10.
AIM/BACKGROUND: Mycoplasmas, especially Mycoplasma fermentans, were suggested more than 20 years ago as a possible cause of rheumatoid arthritis but this hypothesis was never substantiated. In view of the superior sensitivity of the polymerase chain reaction (PCR) assay over culture, the aim was to use this method to seek M fermentans and M penetrans in synovial samples from patients with various arthritides. METHODS: Synovial fluid samples (n = 154) and synovial biopsy specimens (n = 20) from 133 patients with various rheumatic disorders were stored at -80 degrees C for between one and 40 months. Aliquots (500 microliters) of the synovial fluid samples were centrifuged and the deposit, and also the synovial biopsy specimens (approximately 1 g) were placed in lysis buffer with proteinase K for DNA extraction. The DNA was tested by using a semi-nested PCR assay for M fermentans and a single-round PCR for M penetrans. RESULTS: M fermentans was detected in the joints of eight (21%) of 38 patients with rheumatoid arthritis, two (20%) of 10 patients with spondyloarthropathy with peripheral arthritis, one (20%) of five patients with psoriatic arthritis, and four (13%) of 31 patients with unclassified arthritis. M fermentans was not found in the joints of the seven patients with reactive arthritis, the 29 with osteoarthritis or post-traumatic hydrarthrosis, the nine with gouty arthritis, nor the four with chronic juvenile arthritis. M penetrans was not detected in any sample. CONCLUSIONS: These findings show that the presence of M fermentans in the joint is associated with inflammatory rheumatic disorders of unknown cause, including rheumatoid arthritis. However, whether this organism triggers or perpetuates disease of behaves as a passenger remains conjectural.  相似文献   
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