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Acute otomastoiditis and its complications: role of CT   总被引:2,自引:0,他引:2  
Acute bacterial (suppurative) otomastoiditis responds to antibiotic treatment; radiologic study is required only when there is clinical suggestion of coalescent mastoiditis, intracranial complications, or an underlying chronic disease. Computed tomography (CT) is the method of choice for evaluating otogenic intra- or extra-cranial complications. CT scans can show stages of disease progression when infection has spread by way of soft tissue, blood, and bone pathways into the dural venous sinuses, meninges, labyrinth, facial nerves, epidural and other intracranial spaces. When there is clinical suggestion of acute coalescent mastoiditis, a CT scan of the temporal bone can confirm the presence of rarefying osteitis, coalescence of the air cells, and subperiosteal abscess.  相似文献   
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Diese wissenschaftliche Stellungnahme der American Heart Association, des European Resuscitation Council, der Heart And Stroke Foundation of Canada, des Australian Resuscitation Council und des Resuscitation Council of Southern Africaist das Ergebnis des 95er Utstein Symposions, das vom 23. - 24. 06.1995 in der Utstein Abtei auf der Insel Mosteroy im Rogaland County in Norwegen stattfand. Erste Entwürfe wurden mit der Bitte um Stellungnahme an alle teilnehmenden Organisationen verschickt: an das Exekutivkommitee des European Resuscitation Council, das Emergency Cardiac Care Committee der American Heart Association (AHA), das Exekutivkommittee der Heart and Stroke Foundation of Canada, das Australian Resuscitation Council, das Resuscitation Council of Southern Africa und an einige unabh?ngige Gutachter. Die Erarbeitung dieser Stellungnahme wurde von dem Science and Coordinating Committee der AHA und dem Exekutiv- komitee des European Resuscitation Council unterstützt.  相似文献   
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A monoclonal antiplatelet antibody (MA-13G8E1) is described that dose- dependently induces platelet aggregation and serotonin release in an Fc- independent fashion. Whereas platelets were equally aggregated by F(ab')2 fragments of this monoclonal antibody (MoAb), its Fab fragments, on the other hand, were inactive, indicating that divalent interaction is an essential requirement to induce platelet activation by MA-13G8E1. In addition, we could show that platelet epitope cross- linking by MA-13G8E1 occurred on the same platelet. MA-13G8E1 stimulated platelet phospholipase C (PLC) and induced activation of protein kinase C (PKC), both of which were almost unaffected by aspirin pretreatment. Furthermore, PLC activation appeared to be a direct antibody-mediated effect, since intracellular Ca2+ rises were not inhibited by EGTA, cytochalasin B, or aggregation-blocking MA-16N7C2 (antiglycoprotein [anti-GP]IIb/IIa). The MA-13G8E1 antigen is constitutively expressed on resting platelets of different species (7,100 +/- 800 molecules per human platelet), but not on other cell types tested. Both immunoprecipitation and affinity isolation by MA- 13G8E1 showed two low-molecular weight proteins (45 and 36 kD), having slightly acidic isoelectric pH levels (4.5 to 5.5) and forming multimolecular complexes. In conclusion, we found an MoAb that is able to induce platelet activation in an Fc-independent fashion. The mechanism involves cross-linking of a hitherto undescribed platelet membrane protein, leading to PLC and PKC stimulation.  相似文献   
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Total seminal zinc concentration, seminal zinc fraction bound to high molecular weight proteins (HMW-Zn%) and zinc content in spermatozoa were assayed in the ejaculates of 90 asthenozoospermic patients subdivided into two study groups: normoasthenozoospermics (group I: n = 50) and oligoasthenozoospermics (group II: n = 40). The zinc concentrations of patients were compared with those of a control group of donors showing normal semen parameters. All samples were also investigated for their sperm membrane functional integrity by the hypo- osmotic swelling test (HOS). The results showed normal total zinc concentrations but very low HMW-Zn% values (P < 0.001) in seminal plasma of the two groups of asthenozoospermic patients compared to the controls. Furthermore higher zinc amounts (P < 0.001) were measured in spermatozoa of oligoasthenozoospermic patients compared to group I and to the control group. Oligoasthenozoospermics also displayed a lower HOS score (P < 0.001) compared to the other two groups. These data suggest that the increased unbound seminal zinc could contribute to the decrease of sperm motility in normoasthenozoospermic and oligoasthenozoospermic patients. A further impairment in sperm motility could occur in the oligoasthenozoospermic patients where the increase of seminal free zinc was followed by a major zinc uptake by spermatozoa. The higher intrasperm zinc content in these patients could be a reflection of their low sperm membrane functionality.   相似文献   
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When infection of prosthetic orthopedic implants is suspected, optimal management requires accurate confirmation or exclusion of infection. The authors retrospectively studied 98 patients with possible infection who underwent scanning with indium-111-labeled white blood cells (WBCs) and subsequently underwent surgery within 14 days. At surgery, 50 patients had infections, as determined by means of culture or histologic results. The diagnostic accuracy of In-111 scanning was compared with that of plain radiography, arthrography, three-phase bone scanning, and various clinical and laboratory findings classically associated with infection. Positive findings on In-111 WBC scans and elevated erythrocyte sedimentation rates were found to be the most predictive variables in the diagnosis of septic prostheses (P less than or equal to .001 and P less than or equal to .002, respectively). Likelihood ratio analysis more clearly demonstrated the superiority of In-111 WBC scanning, with positive and negative scans yielding likelihood ratios of 5.0 and 0.16, respectively.  相似文献   
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