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991.
To determine whether there are anatomical correlates for intraterminal Ca2+ stores to regulate exocytosis of dense-cored vesicles (DCVs) and whether these stores can modulate exocytosis of synaptic vesicles, we studied the spatial distributions of DCVs, smooth endoplasmic reticulum (SER), and mitochondria in 19 serially reconstructed nerve terminals in bullfrog sympathetic ganglia. On average, each bouton had three active zones, 214 DCVs, 26 SER fragments (SERFs), and eight mitochondria. DCVs, SERFs and mitochondria were located, on average, 690, 624, and 526 nm, respectively, away from active zones. Virtually no DCVs were within "docking" (i.e., < or = 50 nm) distances of the active zones. Thus, it is unlikely that DCV exocytosis occurs at active zones via mechanisms similar to those for exocytosis of synaptic vesicles. Because there were virtually no SERFs or mitochondria within 50 nm of any active zone, Ca2+ modulation by these organelles is unlikely to affect ACh release evoked by a single action potential. In contrast, 30% of DCVs and 40% of SERFs were located within 50 nm of the nonspecialized regions of the plasma membrane. Because each bouton had at least one SERF within 50 nm of the plasma membrane and most of these SERFs had DCVs, but not mitochondria, near them, it is possible for Ca2+ release from the SER to provide the Ca2+ necessary for DCV exocytosis. The fact that 60% of the mitochondria had some part within 50 nm of the plasma membrane means that it is possible for mitochondrial Ca2+ buffering to affect DCV exocytosis. 相似文献
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Postpsychotic state, convalescent environment, and therapeutic relationship in schizophrenic outcome
The authors evaluated the following variables in the 2-3-year outcomes of 30 schizophrenic patients: the acute/chronic dichotomy, the presence of a postpsychotic regressive state, the quality of the convalescent environment, and the formation of a therapeutic relationship. They found that the presence of a postpsychotic regressive state was not associated with either good or poor short-term outcome; that the diagnosis of acute schizophrenia was almost invariably followed by good outcome, but a diagnosis of chronic schizophrenia had little predictive value; and that a favorable convalescent environment and the presence of a therapeutic relationship were signigicantly associated with good outcome. 相似文献
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A questionnaire that included 19 personality, socioeconomic, and general background variables was administered to 160 childless Caucasian, Protestant wives of college students to discover variables that offered promise as predictors of desired family size. Of the samples, 66% wanted two children, and 14% wanted three children. Four variables--feelings of alienation, father's social class level, level of overt anxiety, and childhood family size--had a combined multiple correlation of .39 with desired family size in a stepwise regression analysis and accounted for almost 15% of the desired family size variance. Results suggest that although desired family size remains difficult to predict, personality factors may be as significant as socioeconomic factors in its prediction. 相似文献
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As with any specialized diagnostic technique, the degree of success and safety of needle biopsy of the thyroid are largely based on experience. While an adequate core of tissue for examination is imperative, the interpretation by the pathologist is equally important. A close liaison of the latter with his clinical colleagues is necessary for optimal pathologic evaluation. A review of this experience during a 20 year period shows that needle biopsy is a reliable diagnostic procedure in more than 90 per cent of the patients. It is unlikely to disseminate the disease or compromise the prognosis, and it is a safe office procedure. 相似文献
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