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991.
Summary In order to assess the actual incidence of gas bubbles trapped within acute intracranial epidural haematomas, as revealed by computed tomography (CT) of the skull, a series of 204 patients with surgically verified epidural haematomas was retrospectively reviewed. Gas bubbles were observed on CT scan in 22.5% of the cases, with the incidence rising to 37% when CT scanners of the last generation were employed. The available data failed to demonstrate the actual source of intracranial gas. No correlation was found between the presence of gas bubbles and outcome. No patient in the whole series showed any sign of intracranial infection.  相似文献   
992.
Estimation of the extent and location of infarct is important for the prognosis and hence therapeutic strategy in patients with acute myocardial infarction (AMI). Because cardiac myosin is the major structural protein of the myocardium, and may thus reflect the extent of injured tissue, we established a new sensitive immunoradiometric assay, using a pair of monoclonal antibodies (Mabs) that specifically bind the myosin heavy chain fragments liberated from the myocyte into plasma after a heart attack. A first Mab is linked to a magnetic solid phase. A second Mab, radiolabeled with 125I, is used to detect myosin trapped on the solid phase by the first Mab during a 3-h incubation. This assay can detect 10 micro-units of myosin per liter and is highly reproducible.  相似文献   
993.
Summary Out of a series of 43 cases operated on for ruptured intracranial aneurysms over a 12-month-period, 32 patients were followed up to 12 months postoperatively with repeated evaluations of cerebral blood flow, using the Xenon133 inhalation technique. No statistically significant differences in cerebral perfusion were detected between the subgroups of good-grade patients, who were submitted respectively to early, or delayed surgery. Depression of flow in the affected hemisphere of poor-grade patients was principally related to the preoperative occurrence of an intracerebral haematoma. The overall results were not consistent with the hypothesis that early surgical intervention results in long-lasting effects on the cerebral circulation.  相似文献   
994.
Three BIOZZI-HR mice were immunized with human growth hormone (hGH). From the determination of the titer, the average equilibrium association constant and the heterogeneity index of the antisera, it was possible to select the most suitable mouse for production of monoclonal antibodies (Mabs). Resulting from a single fusion, eight Mabs were produced, purified and characterized. The equilibrium association constant of the Mabs ranged from 5.10(8) M-1 to 9.109 M-1 at physiological pH. Four areas on hGH are recognized by the Mabs (the topology of the Mabs was investigated by two-site immunoradiometric assays). The Mabs, which recognize a same area, show similar cross-reactivities between hGH and human Placental Lactogen (hPL). No selected Mabs bound human Prolactin (hPRL), equine Growth Hormone (eGH) and porcine Growth Hormone (pGH). Two complementary Mabs enable a two-site immunometric assay of pituitary and E. Coli derived hGH.  相似文献   
995.
Computed tomography and magnetic resonance imaging in spinal hydatidosis   总被引:1,自引:0,他引:1  
Computed tomography and magnetic resonance imaging in patients with spinal hydatidosis provide comprehensive evaluation of the actual extent of the disease. Paravertebral uncalcified cysts, hardly recognizable by conventional radiologic examinations, are clearly shown by both methods. Initial involvement of the spongy bone is evident in computed tomography scans, in contrast to what usually appears to be normal in plain films or tomograms. Occurrence of cysts within the spinal canal is revealed by both types of computed scans, with magnetic resonance imaging being able to provide further information on the involvement of the spinal cord.  相似文献   
996.
By means of special probes, air temperatures were determined in external auditory meatus and in "radical" mastoid cavities. Under normal conditions, there was no difference between the two groups, the temperature next to the drum head being in the same range as the body temperature. Exposure to simulated wind only lowered the temperature significantly in cases with very wide external meatus; e.g., after surgery. Suction--as is used in the daily practice of cleaning ears in the ENT surgery--caused a very abrupt decrease in temperature. In cases with open mastoid cavities, there was vertigo with nystagmus, due to the caloric vestibular stimulus. -Operative techniques such as the obliteration of such cavities or the reconstruction of the posterior wall of the meatus can considerably reduce this phenomenon.  相似文献   
997.
The clinical manifestations of cytomegalovirus (CMV) infection in persons with AIDS are described, and recent advances in the management of these syndromes with antiviral agents are reviewed. CMV infection is the most common serious opportunistic viral infection in AIDS patients. Clinical manifestations include chorioretinitis, gastroenteritis, hepatitis, pneumonia, CNS infection, adrenalitis, and a wasting syndrome. The diagnosis of CMV infection requires laboratory demonstration of a serologic response to the virus, detection of viral components or products, or isolation of the virus. Ganciclovir is an acyclic nucleoside analogue marketed for the treatment of CMV-related retinitis in immunocompromised hosts. After i.v. ganciclovir induction therapy, more than 80% of patients show improvement or stabilization of retinitis. Relapse is common in AIDS patients, however, and low-dose i.v. maintenance therapy is recommended. The most serious dose-limiting effect is neutropenia. Intravitreal injection of ganciclovir has been well tolerated and efficacious. Ganciclovir has shown some efficacy in the treatment of other life-threatening CMV infections, especially gastroenteritis, but data are limited. Ganciclovir-resistant strains have been reported. Foscarnet, a pyrophosphate analogue with activity against both human CMV and human immunodeficiency virus, is undergoing clinical trials. Foscarnet has shown promise in the therapy of CMV-related retinitis, but results for other CMV infections are disappointing. Nephrotoxicity is the major dose-limiting effect. AIDS patients with sight-threatening and rapidly progressive CMV-related retinitis should be treated with ganciclovir. Foscarnet may offer an alternative when it becomes available. More must be learned about the efficacy of these drugs in the treatment of CMV infection in patients with AIDS.  相似文献   
998.
OBJECTIVE: The aim of this study was to analyze several fibrinolytic components and coagulation inhibitors in postmenopausal women and to evaluate the effect of hormone replacement therapy.STUDY DESIGN: Several hemostatic parameters were evaluated in 75 postmenopausal women before and after 3 to 4 and 12 months of hormone therapy.RESULTS: An increase in plasma fibrinolytic activity primarily related to a significant increase in tissue-type plasminogen activator and a decrease in plasminogen activator inhibitor type 1 was observed in women receiving hormone replacement therapy. A significant decrease in protein S and lipoprotein(a) was detected under therapy. No modifications in tissue-type plasminogen activator/plasminogen activator inhibitor-1 and activated protein C/α1-antitrypsin complexes, urokinase activity, plasminogen, and antithrombin III were detected.CONCLUSIONS: The increase in fibrinolytic activity and the decrease in lipoprotein(a) levels observed in women receiving hormone replacement therapy could help decrease the risk of coronary disease associated with the postmenopausal state.  相似文献   
999.
Bilateral Parkinsonism has been observed in a 60-year-old female with a chronic subdural intracranial haematoma. Scattered, poorly marginated, hypodense areas within the ipsilateral pallidus and putamen were evident on the preoperative CT scans. The rapid neurological improvement following the surgical drainage of the subdural clot and the evolution of the densitometric features of the nuclear lesions, which became clear-cut, though smaller, in the following months, suggest a cause-and-effect relation between the haematoma and the clinical symptomatology. To the best of our knowledge this is the first case in which anatomical lesions within the basal ganglia could be detected neuroradiologically.  相似文献   
1000.
The influence of age on the pulmonary clearance of 99Tcm-DTPA radioaerosol   总被引:2,自引:0,他引:2  
Age-dependent changes of 99Tcm-DTPA radioaerosol transpulmonary clearance have been investigated in 49 healthy volunteers with an age range of 21-63 years. The clearance was uniformly increased in all smokers irrespective of age, but it showed a highly significant (p less than 0.001) decrease in non-smoking patients over 50 years. Several age-related changes in the ageing lung can contribute to this decreased clearance, but the reduced alveolar-capillary surface area available for the transport is probably the key factor. The practical implication of the results is the need to use age-related normal ranges when interpreting 99Tcm-DTPA radioaerosol clearance studies.  相似文献   
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