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Memory performance of elderly patients in the early stages of Alzheimer's disease (DAT) was compared with that of elderly control subjects. In explicit tests of recognition memory, which involve conscious recollection, the DAT patients were grossly impaired. In implicit tests of anagram solution and wordstem completion, which do not require conscious recollection, the DAT patients were not impaired. These findings further support the idea that a separate memory system, episodic memory, underlies conscious recollection, that it is this system which is most commonly damaged in amnesia, and that memory systems not involving conscious recollection may be spared in the early stages of Alzheimer's disease.  相似文献   
994.
Cerebro-oculo-facial-skeletal (COFS) syndrome is a rare, autosomal recessive syndrome characterized by microcephaly, microphthalmia and/or cataracts, neurogenic arthrogryposis, and multiple congenital anomalies. A term female infant with COFS syndrome who developed infantile spasms at the age of 3 months is reported. The patient had a good response to intramuscular ACTH with disappearance of infantile spasms and resolution of the hypsarrhythmic pattern on electroencephalography succeeded by a slow, synchronous pattern. Modified hypsarrhythmia returned after ACTH therapy was discontinued. Infantile spasms have not previously been reported in association with COFS syndrome and are a potentially treatable aspect of the disease. This patient may add to the clinical spectrum of COFS syndrome or may have a variant.  相似文献   
995.
Diabetes-prone BioBreeding/Worcester (BB/Wor) rats received thrice weekly injections of mAb against antigens expressed on the surface of all T cells (OX19), cytotoxic/suppressor, and NK cells (OX8), helper/inducer cells (W3/25, OX35, OX38), and Ia+ cells (OX6, 3JP, OX17). Treatment with OX8 or OX19 achieved stable reductions of splenic and peripheral blood NK cells and helper/inducer T lymphocytes, respectively, and protected against diabetes. OX19 injections also prevented lymphocytic insulitis, thyroiditis, and the synthesis of autoantibodies to thyroid colloid and smooth muscle antigens. OX8 injections reduced splenic NK-mediated YAC-1 cell lysis, but did not prevent insulitis, thyroiditis, or autoantibody synthesis. Injections of mAb specific for antigens on the surface of helper/inducer cells, and for cells expressing IaE antigens provided marginal protection against diabetes without reductions of phenotypic subsets. These findings suggest that pancreatic beta cell destruction in the spontaneously diabetic BB/Wor rat is mediated by the combined action of NK and helper/inducer cells.  相似文献   
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997.
The neuronal morphological development of the avian telencephalic cortex (DMC) is studied in Golgi-stained brain sections. The neuronal types at embryonic days 10, 13, 16, as well as of newborn chick are identified. The immature neurons are characterized by the presence of hair-like processes, growth cones and dendritic varicosities. These characteristics are absent in neuronal types of newborn chick. There are five patterns of differentiation, which produce six neuronal types in the newborn chick: horizontal neurons, pyramidal neurons, bipyramidal neurons, short axon multipolar neurons, long axon multipolar neurons and periventricular neurons. The morphological features of migrating embryonic cells are described. The dendritic spines appear in 16-day embryos in the majority of neuronal types.  相似文献   
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999.
Esophageal stricture is not reported to be a common complication of nasogastric intubation. Two patients who had a Levin tube inserted in the stomach for nutrition during a prolonged coma, and finally presented with a severe esophageal stricture were observed and treated. The clinical history of the patients suggests that the pathogenesis of this lesion is probably multifactorial, secondary to induced gastroesophageal reflux, impaired esophageal clearance, high gastric acid output, and use of steroids. Jejunostomy feeding, rather than nasogastric feeding, is probably a better means to provide nutritional support in comatose patients, thus averting the risk of such a serious complication. Esophageal replacement with left colon interposition appears the treatment of choice for these severe esophageal strictures.  相似文献   
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