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941.
33 patients with suspected coronary artery disease were studied hemodynamically and angiocardiographically in the resting state and following administration of 0.4 mg of sublingual nitroglycerin (NTG). After NTG several parameters were changed: LVEDP, mean LV systolic pressure, EDVI, ESVI, SVI and SWI were decreased; EF, mean Vcf, MNSER, heart rate (P less than 0.01; r = 0.801) and chords, hemichords and shortening of long axis were increased. However, the changes after NTG were markedly different in patients with diffuse and localized LV asynergy, suggesting a more important inotropic effect of NTG in patients with localized LV asynergy, while reduction in venous return and EDV would be the main effect of NTG in patients with diffuse LV asynergy.  相似文献   
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The effects of a serial dilution of linoleic acid on human spermatozoa in whole semen was tested on 21 semen samples obtained from 11 normal volunteers. The minimal concentration of linoleic acid required to stop the movement of at least 75% of the moving sperm ranged from 1 to greater than 100 mg/dl. Fifteen of 21 (71%) of the semen samples were inhibited by added free fatty acids (FFA) concentrations that were less than or close to the physiologic concentration ranges of FFA in blood plasma (1 to 30 mg/dl). The immobilized sperm often formed aggregates similar to those formed by the action of autoantibodies against sperm cells. Preliminary studies conducted on a variety of other FFA have indicated that oleic acid (18/1) was less toxic than linoleic acid (18/2) and that linolenic acid (18/3) was more toxic than linoleic acid. The saturated FFA palmitic acid (16/0) and stearic acid (18/0) at concentrations up to 100 mg/dl showed little or no toxicity to sperm cells. It is suggested that FFA toxicity be included among physiologic factors that affect the motility and spontaneous aggregation of sperm cells.  相似文献   
946.
Vestibular habituation was studied in normal subjects and in patients with cerebellar disease using a stimulation paradigm proposed in this paper. Six caloric stimuli were repeated daily in the same ear during six days and electronystagmographic responses at the beginning and the end of that period were compared. The normal behaviour was a clear reduction of the response across time. Two groups of cerebellar patients were identified by their ability to recover from positional imbalance after treatment. Compensated patients responded to repeated caloric stimulation in the same way as normal subjects. Conversely, uncompensated patients increased their response after the stimulation paradigm. The role played by the cerebellum in vestibular plasticity is discussed together with the observed correlation between vestibular habituation and the ability for postural recovery to occur.  相似文献   
947.
Diffuse leptomeningeal gliomatosis is a rare condition characterized by glioma in the leptomeninges without a dominant mass lesion. The difficulty in diagnosis of this condition, its rarity. and its extensive nature have hampered its successful treatment. Most cases of primary diffuse leptomeningeal gliomatosis have occurred in adults. Reported here is a case of this condition in a 9-year-old girl; to the authors' knowledge, she is the youngest patient with diffuse leptomeningeal gliomatosis and the longest survivor of the malignant variety.  相似文献   
948.
Fractalkine receptor (CX3CR1)‐deficient mice develop very severe experimental autoimmune encephalomyelitis (EAE), associated with impaired NK cell recruitment into the CNS. Yet, the precise implications of NK cells in autoimmune neuroinflammation remain elusive. Here, we investigated the pattern of NK cell mobilization and the contribution of CX3CR1 to NK cell dynamics in the EAE. We show that in both wild‐type and CX3CR1‐deficient EAE mice, NK cells are mobilized from the periphery and accumulate in the inflamed CNS. However, in CX3CR1‐deficient mice, the infiltrated NK cells displayed an immature phenotype contrasting with the mature infiltrates in WT mice. This shift in the immature/mature CNS ratio contributes to EAE exacerbation in CX3CR1‐deficient mice, since transfer of mature WT NK cells prior to immunization exerted a protective effect and normalized the CNS NK cell ratio. Moreover, mature CD11b+ NK cells show higher degranulation in the presence of autoreactive 2D2 transgenic CD4+ T cells and kill these autoreactive cells more efficiently than the immature CD11b? fraction. Together, these data suggest a protective role of mature NK cells in EAE, possibly through direct modulation of T cells inside the CNS, and demonstrate that mature and immature NK cells are recruited into the CNS by distinct chemotactic signals.  相似文献   
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