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Acute gastric stress ulceration was induced in rats by cold restraint and was not associated with alteration of gastric pH or serum gastrin level. Cimetidine and oral and intravenous allopurinol were prophylactic but allopurinol was more effective in reducing the depth of the lesion and acted without alteration in gastric pH. The efficacy of allopurinol in preventing stress ulceration offers further indirect evidence of the role of ischaemia and oxygen free radical generation in the aetiology of stress ulceration.  相似文献   
44.
MR has emerged as the imaging modality of choice for the brain in patients presenting with seizures, chronic headaches, progressive neurologic deficits, ataxia, vertigo, hearing loss, visual loss, congenital abnormalities, signs of increased intracranial pressure, dementia, suspected multiple sclerosis, and in the vast majority of other elective neurologic problems. CT should currently be considered the primary imaging modality in patients with acute neurologic deficits (stroke), acute onset of severe headaches, and when fine bone detail is required. Acutely injured patients are more readily studied with CT. The vast majority of patients in whom CT is preferred are seen in emergent situations, frequently in hospital emergency rooms. The effects of trauma beyond the acute stage are best evaluated with MR. In the future, MR is likely to become the procedure of choice in even more clinical situations than at present. A summary of currently recommended primary imaging modalities in various clinical situations is provided in Table 1.  相似文献   
45.
In the present study we have evaluated the effect of recombinant human fibroblast, IFN-beta ser, and immune, IFN-gamma, interferon, alone and in combination, on the proliferation of fifteen early passage human glioblastoma cell cultures. Explant cultures were established from glioblastoma tumor tissue obtained at the time of surgery. After sufficient outgrowth, cultures were dispersed with trypsin/versene and maintained as independent cell lines. IFN-beta ser induced a greater than or equal to 50% reduction in the 7 day growth of 6 of the 15 cultures. The majority of cultures, 9 of 15, displayed less than or equal to 50% growth suppression in comparison with control cultures after 7 days exposure to 2000 Units/ml of IFN-beta ser. When treated with 2000 Units/ml of IFN-gamma, only 1 of the 15 glioblastoma cultures exhibited a greater than or equal to 50% reduction in growth. In contrast, when treated with the combination of IFN-beta ser plus IFN-gamma, 1000 Units/ml of each interferon preparation, 12 of 15 cultures were inhibited by greater than or equal to 50% after 7 days growth. The combination of interferons was effective in suppressing glioblastoma growth both in cultures displaying relative sensitivity and those exhibiting innate resistance to either or both types of interferon when employed alone. One glioblastoma culture, G-7, was studied through 45 passages and displayed the same sensitivity at different passages to growth inhibition when exposed to IFN-beta ser, IFN-gamma or both interferons. Based on previous clinical studies indicating that IFN-beta or IFN-gamma when administered alone to patients do not generally alter the clinical progression of malignant gliomas, the present results suggest that the combination of IFN-beta plus IFN-gamma may prove more effective than either agent alone in the clinical treatment of patients with glioblastoma multiforme.  相似文献   
46.
ABSTRACT Isolated congenital tricuspid valve dysplasia is a rare and potentially lethal congenital heart disease that can be easily confused with persistent pulmonary hypertension of the newborn. We describe a neonate with isolated congenital tricuspid valve dysplasia who did not respond to mechanical ventilation but improved by tolazoline. Clinicians should be aware that the initial fulminant course of this condition may be reversed by reducing the pulmonary vascular resistance, thereby allowing time for spontaneous recovery.  相似文献   
47.
Magnetic resonance (MR) imaging has rapidly evolved as a primary modality for evaluating the spine. Following routine radiographs, MR is currently the preferred examination in evaluating patients presenting with myelopathy, suspected congenital abnormalities, discitis/osteomyelitis, and myeloradiculopathy. It is becoming the examination of choice in evaluating patients with radiculopathy as well when fast-scan techniques are available. MR of the spine will prove increasingly important as the technology advances. It is likely that MR will replace myelography entirely for many indications.  相似文献   
48.
Grossman  LB; Buonocore  E; Modic  MT; Meaney  TF 《Radiology》1984,150(2):323-325
Forty-three patients with acquired and congenital abnormalities of the thoracic aorta were studied using digital subtraction angiography (DSA) after an intravenous bolus injection of 40 ml of contrast material. Abnormalities studied included coarctation, pseudocoarctation, Marfan syndrome, cervical aorta, double aortic arch, aneurysm, dissection, and tumor. Twenty-four patients also had conventional angiography. DSA was accurate in 95% of cases; in the other 5%, involving patients with acute type I dissection, the coronary arteries could not be seen. The authors concluded that in 92% of their patients, DSA could have replaced the standard aortogram.  相似文献   
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Background  

Surgery for perforated peptic ulcer disease is one of the most common emergency procedures carried out in the western world.The role of postoperative empiric Helicobacter Pylori eradication therapy is controversial.  相似文献   
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