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991.
The authors present the results of a transmission electron-microscopic study performed on a tissue sample obtained by an intraocular fine-needle aspiration biopsy in a case of retinoma. The ultrastructural study showed that the tumor was composed mainly of granular osmiophilic material which contained some tumor cells. These cells showed peculiar ultrastructural characteristics, which demonstrated their neural character, and appeared in different degenerative stages. Apparently, this is the first case in whom ultrastructural technique have been applied to study an intraocular tumor sample obtained by intraocular fine-needle aspiration biopsy, and the first case of retinoma studied by such a diagnostic approach.  相似文献   
992.
An eye protection program is needed in occupational medicine policies. Typical eye injuries and eye accidents, as they relate to occupational accidents, justify the management advocating such a program. A recommended model for a functional eye protection program is provided and defined.  相似文献   
993.
Central sensory and motor conduction in vitamin B12 deficiency.   总被引:7,自引:0,他引:7  
Four patients with subacute combined degeneration were studied through upper and lower limb SEPs recorded with a non-cephalic reference montage and through cortical and spinal magnetic stimulation. Clinical signs were confined to the lower limbs in 3 patients; the remaining patient presented only paraesthesiae in 4 limbs. Median nerve SEPs showed a normal cervical N13 response with a significant increase of central conduction time concerning exclusively the P9-P14 interpeak interval. Central motor conduction to upper and lower limb muscles was abnormal. Nerve conduction studies provided no evidence of peripheral nerve involvement. These electrophysiological findings suggest that in vitamin B12 deficiency the higher segments of the cervical cord are usually affected first and that central sensory and motor conduction studies are sensitive methods for detecting such damage.  相似文献   
994.
Disease processes in the peritoneum, omentum, and mesentery occasionally are not recognized at radiologic examination. The authors have used computed tomography (CT) to categorize the radiologic appearances of the more common abnormalities into three basic patterns: (a) solid but relatively well-defined masses, (b) cystic-appearing masses, and (c) ill-defined or infiltrative processes. The most common solid masses to affect these anatomic regions are secondary neoplasms, which are associated with enhancement of the peritoneum on contrast material-enhanced CT scans and, typically, ascites. The various cystic-appearing masses (including cystic lymphangioma, cystic mesothelioma, teratoma, and loculated ascites) and infiltrating masses (such as peritoneal mesothelioma, retractile mesenteritis, desmoid, and carcinoid) must be differentiated on the basis of clinical findings and additional imaging findings (eg, CT depiction of fat and calcium in teratomas and the radiating appearance of carcinoids). Although the CT appearances of some of the abnormalities overlap, classifying them by pattern is helpful in narrowing the range of the differential diagnosis.  相似文献   
995.
We describe the types of aggressive behaviour and determine their prevalence in a sample of hospitalized elderly psychiatric patients. Data were obtained by nurse ratings of aggressive behaviour using the recently developed Rating Scale for Aggressive Behaviour in the Elderly; 90 patients were rated over a 3-d period. Nearly half the sample were at least mildly aggressive; the frequencies of some specific types of aggressive behaviour were high. In contrast, the frequency of injuries and the use of restraints and medication for aggressive behaviour were low. Some correlates of the aggressive behaviour were also analysed.  相似文献   
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The effects of various neurotransmitters on phosphoinositide hydrolysis, mobilization of Ca2+ and release of [3H]-norepinephrine ([3H]-NE) were studied in cultures of sympathetic neurons of chick embryos. [3H]-inositol-1,4,5-triphosphate ([3H]-IP3) was increased in sympathetic neurons by acetylcholine (ACh), muscarine and serotonin (5-HT). Dopamine and norepinephrine did not stimulate phosphoinositide hydrolysis. Intracellular concentration of free Ca2+ ([Ca2+]i) was measured in Indo-1-loaded sympathetic neurons at rest and after addition of test agents. Measurements were made in the cell body and growth cone regions since Ca2+ mobilization is known to be different in different regions of the sympathetic neurons. ACh (nicotinic component was blocked by hexamethonium) and 5-HT failed to increase the [Ca2+]i, in the cell body as well as in the growth cone. The spontaneous release of [3H]-NE was not affected by ACh and 5-HT. Caffeine increased the [Ca2+]i only in the cell body but not in the growth cone and had no effect on the release of [3H]-NE. These results suggest that an IP3-insensitive but caffeine-sensitive pool of Ca2+ is present only in the somatic region of sympathetic neurons and is not coupled to the transmitter release.  相似文献   
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