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11.
Corticotropin-releasing factor (CRF) administered intracerebroventricularly produced both a rapid, greater than 50% reduction in splenic natural killer (NK) cytotoxicity and a prolonged elevation in plasma corticosterone levels. In the first 60 minutes following CRF, fivefold increases in corticosterone levels were associated with the suppression of NK activity. However, NK activity returned to control levels at later time points even though elevated plasma corticosterone levels persisted. These data augment the findings that central CRF reduces natural cytotoxicity and establish a time course for the effect in acutely treated rats.  相似文献   
12.
Pseudomembranous tracheobronchitis caused by Aspergillus   总被引:1,自引:0,他引:1  
Four immunosuppressed patients with a rapidly evolving, febrile, respiratory distress syndrome were found at autopsy to have Aspergillus pseudomembranes of their lower tracheobronchial tree. Steroids, neutropenia, broad spectrum antibiotic use, and alcoholism appear to be predisposing risk factors. Bronchoscopy may reveal the pathology but antemortem diagnosis is difficult because of the low yield of sputum cultures and fulminant nature of the disease.  相似文献   
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14.
The cases of two lactating mothers whose milk from right and left mammary glands differed dramatically in protein concentration and composition are presented. The discordance in protein quality between the two breast milks underscores the need to sample both breasts in future studies of milk proteins and suggests that each breast may possess some degree of autonomy with respect to milk protein production.  相似文献   
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The effects of the serotonin-releasing compound p-chloroamphetamine (PCA, 2.5 mg/kg) on avoidance acquisition, retention and memory retrieval were examined in male Sprague-Dawley rats using a one-way active avoidance and a one-trial passive avoidance task. The drug was injected IP prior to training, following acquisition and prior to the retention test 24 hr after training using a state-dependent design. In the normal context situation pretraining administration of PCA markedly impaired active avoidance acquisition, but PCA-treated rats did not differ from controls in their retention performance when tested 24 hr after training. In the dark/light box test pretraining administration of PCA caused a dose-dependent impairment of both active and passive avoidance retention which could not be explained in terms of changes in locomotor activity or behavioural disinhibition at the time of testing or state-dependent retention. Post-training administration of PCA failed to affect avoidance retention in both tasks. The drug was found to impair memory retrieval in a dose- and time-dependent fashion in the one-way active but not in the passive avoidance test. Pretraining administration of PCA produced a progressive loss of passive and active avoidance performance at increasingly longer retention intervals. The present results suggest that serotonin has dual effects on processes underlying learning and memory involving effects on both associative and non-associative learning processes in the rat. The time-dependent loss of memory retention following 5-HT release indicates that serotonin has a role in the way information is processed in the brain.  相似文献   
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Is hyperreactivity the same as asthma?   总被引:1,自引:0,他引:1  
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19.
We reviewed our first 53 lengthenings performed in 45 patients with an average age of 19 years at the time of lengthening. The shortening was congenital in 16 patients, post-traumatic in 15 and had various causes in the 14 remaining. 31 femurs and 22 tibias with an average shortening of 6 and 5 cm, respectively, were lengthened 6 (2-14) cm. The aim was achieved in all but 4 patients, where lengthening had to be discontinued due to complications.

Potential complications of lengthening can be numerous but, if recognized, can in most cases be dealt with during the extended lengthening procedure. 38 cases of pin-tract infections healed with antibiotics. Restricted motion in one or more joints was registered in 49 cases during lengthening; minor restriction of joint motion persisted in 14 patients. 28 cases had angular deviations during lengthening. After additional surgery all but 10 could be corrected. 4 fractures occurred after removal of the external fixator. The total number of complications was 146, and of these 76 were minor, 42 moderate and 28 severe. 36 of the 42 patients available to follow-up were satisfied with the results of the lengthening procedure.  相似文献   
20.
In order to study clinicopathologic features of hepatocellular carcinoma (HCC) and their relation to metastatic growth, all autopsied cases with confirmed HCC (n = 490) from a period with a high autopsy frequency in a well-defined population were analyzed. Cirrhosis, usually of micronodular type, was found in 72%. The gross appearance of the tumour was predominantly massive (46%) or multinodular (42%). The tumour involved both liver lobes in 72% or the right lobe alone in 20%. Histologically, trabecular growth (79%) and grade II of differentiation (52%) prevailed. Vascular invasion was noted in 56%, whereas involvement of the biliary tract was unusual (4%). Metastases especially involved lymph nodes (42%), lungs (18%) and skeleton (17%). Increased weight of the liver, multinodular appearance, involvement of both liver lobes, low grade of differentiation and vascular invasion were significantly associated with presence of metastases.  相似文献   
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