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81.
Dysembryoplastic neuroepithelial tumor (DNT) is a recently described rare brain neoplasm with characteristic clinical and morphological features and favorable prognosis. We report here two cases of DNT. The first concerned a 12 years old girl who presented complex seizures preceded by acoustic aura (melodies). Computed tomography revealed a hypodense tumor measuring 2 x 2.5 cm in diameter, located paracortically in the left temporal lobe. The second tumor was removed from a 21-year-old man with partial complex seizures. Nine years earlier patient underwent neurosurgery with partial removal of the tumor The tumor's histopathologic diagnosis is unfortunately lacking. Computed and magnetic resonance imaging showed a mass occupying the cortex and paracortical areas of the anterior pole of the temporal lobe. Histologically, both tumors consisted of small, S-100 protein immunopositive oligodendrocyte-like cells (OLCs) arranged between synaptophysin- and, to a lesser degree, NFP-immunopositive axons (glioneuronal element). In the second case, an area of pilocytic astrocytoma-like appearance was also found, these cells were immunopositive for GFAP. The present study provides clinical, radiological and histological data, which may be helpful in differential diagnosis of this newly recognised brain tumor.  相似文献   
82.
This article reviews pharmacologic approaches to treating acute respiratory distress syndrome (ARDS). The authors discuss the therapeutic effects of ketoconazole, antioxidants, corticosteroids, surfactant, ketanserin, pentoxifylline, bronchodilators, and almitrine in ARDS. Current animal data and proposed mechanics which may foster future pharmacologic therapies are also examined.  相似文献   
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84.
Skin samples from a rabbit hind limb were taken from controls and at 5 min, 2 and 6 hr after a mild thermal injury (60 degrees C for 1 min). Large aggregates of intercellular particles, usually ribosomal in appearance, were seen in 6 hr samples and were accompanied by some peripheral aggregates of particles and by granule-coated vesicles. These structures were present in earlier samples to a lesser extent and were absent from control material. Quantitative assessment showed that intercellular particles apparently increased up to 6 hr whereas peripheral aggregation was maximum at 2 hr. Histochemical analysis confirmed that the particles contained ribonucleoprotein. Other larger particles were seen occasionally and contained carbohydrate. Lymph draining the site showed cellular changes, little change in enzyme activities, and no aggregates of particles.  相似文献   
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86.
We report a case of leiomyosarcoma of the pancreas. A spindle cell pattern at light microscopy, immunocytochemical reactivity with desmin, alpha-1-antitrypsin, vimentin and actin and ultrastructural features of smooth muscle differentiation help to establish the diagnosis.  相似文献   
87.
Anterior pituitary glands of intact diestrous and gonadectomized female rats were incubated with a supramaximally active dose of LH-RH. Puromycin (P) and cycloheximide (C) did not consistently affect the LH release from glands of ovariectomized rats. In intact rats, LH release induced by LH-RH occurred in two phases, an initial one (relatively slow rate of release) and a secondary one (high rate of release). P and C had no effect on the initial phase, but prevented the secondary one. Pre-incubation with LH-RH prevented the effect of P and C added after 4 hours. Since P and C did not affect the total amount of LH present in media and hypophyses, the LH-released during the P- and C-sensitive phase is not newly formed LH. It is concluded that LH-RH induces the synthesis of protein which is necessary for LH-RH-induced LH release. The initial phase of LH release is made possible by protein already present in the glands at the beginning of the experiment.  相似文献   
88.
A recent paper discussed the way in which microprocessors are being used for teaching computer science at Strathclyde University. This article discusses an alternative system being implemented at Rhodes University. The chief difference between the two is the attitude towards breakdowns.  相似文献   
89.
10 Patients with positive orthostatic dysregulation were investigated with regard to venous capacity, heart frequency and arterial blood pressure both lying down and sitting up. The venous capacity was reduced by 14% after dehydroergotamine (DHE) in the lying position, which is an expression of increased venous tone. There is no change in venous capacity following the administration of beta blockers in the lying position. Under orthostatic conditions beta blockers bring about an approximate normalization of the venous capacity reaction, whereas the abnormal response following placebo administration is only slightly altered by DHE.  相似文献   
90.
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