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981.
Cognitive function was investigated in a random sample of subjects on the general practitioners' registry of hypertensive patients in an inner city area and matched with normotensive controls. The response rate was 66% giving 90 matched pairs, average age 63 yrs, with 47% men. There was no difference in educational background or measures of reading ability between the two groups. Cognitive function tests showed a consistent trend of poorer performance in hypertensives, with significant differences in Verbal Learning (immediate recall and retention). Age was inversely related to cognitive function, but no additional deterioration with increasing age was shown in hypertensives. 相似文献
982.
Cells possess within their epigenetic repertoire the ability to undergo an active process of cellular suicide termed programmed (or apoptotic) cell death. This programmed cell death process involves an epigenetic reprogramming of the cell that results in an energy-dependent cascade of biochemical and morphologic changes (also termed apoptosis) within the cell, resulting in its death and elimination. Although the final steps (i.e., DNA and cellular fragmentation) are common to cells undergoing programmed cell death, the activation of this death process is initiated either by sufficient injury to the cell induced by various exogenous damaging agents (e.g., radiation, chemicals, viruses) or by changes in the levels of a series of endogenous signals (e.g., hormones and growth/survival factors). Within the prostate, androgens are capable of both stimulating proliferation as well as inhibiting the rate of the glandular epithelial cell death. Androgen withdrawal triggers the programmed cell death pathway in both normal prostate glandular epithelia and androgen-dependent prostate cancer cells. Androgen-independent prostate cancer cells do not initiate the programmed cell death pathway upon androgen ablation; however, they do retain the cellular machinery necessary to activate the programmed cell death cascade when sufficiently damaged by exogenous agents. In the normal prostate epithelium, cell proliferation is balanced by a equal rate of programmed cell death, such that neither involution nor overgrowth normal occurs. In prostatic cancer, however, this balance is lost, such that there is greater proliferation than death producing continuous net growth. Thus, an imbalance in programmed cell death must occur during prostatic cancer progression. The goal of effective therapy for prostatic cancer, therefore, is to correct this imbalance. Unfortunately, this has not been achieved and metastatic prostatic cancer is still a lethal disease for which no curative therapy is currently available. In order to develop such effective therapy, an understanding of the programmed death pathway, and what controls it, is critical. Thus, a review of the present state of knowledge concerning programmed cell death of normal and malignant prostatic cells will be presented. 相似文献
983.
984.
B Ghetti P Piccardo MG Spillantini Y Ichimiya M Porro F Perini T Kitamoto J Tateishi C Seiler B Frangione O Bugiani G Giaccone F Prelli M Goedert SR Dlouhy F Tagliavini 《Canadian Metallurgical Quarterly》1996,93(2):744-748
Deposition of PrP amyloid in cerebral vessels in conjunction with neurofibrillary lesions is the neuropathologic hallmark of the dementia associated with a stop mutation at codon 145 of PRNP, the gene encoding the prion protein (PrP). In this disorder, the vascular amyloid in tissue sections and the approximately 7.5-kDa fragment extracted from amyloid are labeled by antibodies to epitopes located in the PrP sequence including amino acids 90-147. Amyloid-laden vessels are also labeled by antibodies against the C terminus, suggesting that PrP from the normal allele is involved in the pathologic process. Abundant neurofibrillary lesions are present in the cerebral gray matter. They are composed of paired helical filaments, are labeled with antibodies that recognize multiple phosphorylation sites in tau protein, and are similar to those observed in Alzheimer disease. A PrP cerebral amyloid angiopathy has not been reported in diseases caused by PRNP mutations or in human transmissible spongiform encephalopathies; we propose to name this phenotype PrP cerebral amyloid angiopathy (PrP-CAA). 相似文献
985.
986.
E Kimura CA Bersani-Amado LS Sudo SR Santos S Oga 《Canadian Metallurgical Quarterly》1997,28(5):695-698
1. The absorption of piroxicam into the blood of rats is significantly slower after oral administration of piroxicam beta-cyclodextrin than of free piroxicam. 2. The pharmacokinetic profiles of piroxicam in rat lymph were very similar in both groups. 3. Bioavailability of piroxicam in plasma is higher after treatment with the inclusion product than with free piroxicam. On the other hand, bioavailability in lymph is higher when free piroxicam is administered. 相似文献
987.
FC Blumberg M Pfeifer SR Holmer EP Kromer GA Riegger D Elsner 《Canadian Metallurgical Quarterly》1998,114(1):94-97
OBJECTIVE: The development of sudden postoperative hearing loss as a complication of microvascular decompression (MVD) operations in the cerebellopontine angle has already been reported. A sudden hearing loss of vascular origin may also occur hours or days after such operations, but even in such cases an improvement of hearing over the following weeks is possible. Here we report on a gradual deterioration of hearing over a period of two weeks after MVD which has not been described in the literature up to now. CLINICAL PRESENTATION: A MVD operation was performed twice on a 36 year old patient with trigeminal neuralgia. After the second operation the patient developed a slight hearing impairment 3 days postoperatively which increased over a period of two weeks and ended up with total deafness. The course of intra-operative brainstem auditory evoked potentials and postoperative audiograms is documented. CONCLUSION: Because of gradual development of the delayed hearing loss, we conclude that postoperative tissue scarring may be the underlying pathology. 相似文献
988.
K Uhlmann A B?ttner A Haidan T Kino M Wiznerowicz H Trzeciak M Ehrhart-Bornstein SR Bornstein 《Canadian Metallurgical Quarterly》1998,24(3-4):753-757
We have investigated the effects of supraphysiological concentrations of catecholamines on glucocorticoid secretion in vitro. These effects were analyzed in adrenocortical cells shown to be present in chromaffin cell cultures as well as in cortical cells cocultured with transfected chromaffin cells that overproduce catecholamines. Cortisol release from residual cortical cells in chromaffin cell cultures was found to be 2.5 times higher than from isolated adrenocortical cells. Removal of the adrenocortical cells from the chromaffin cells resulted in an almost complete cessation of cortisol secretion. Catecholamine overproduction was achieved by transfecting chromaffin cells with the blank retroviral vector pSAM-EN. Coculture of adrenocortical cells with these transfected chromaffin cells further enhanced the stimulating effect of chromaffin cells on cortisol 2.3-fold compared to normal cocultures. In conclusion, cortical cells in chromaffin cell cultures secrete significant amounts of cortisol, which should be considered when evaluating the endocrine function of these cell cultures and which can be abolished by purification. The hormonal activity of adrenocortical cells is highly increased in an environment of catecholamine overproduction, which is of both basic and clinical importance. 相似文献
989.
The study examined whether spouses' attributions for partner behavior are related to their own behavior by assessing their attributions and observing the problem-solving discussions of couples in which (a) neither spouse was depressed or maritally distressed, (b) the wife was depressed and both spouses were maritally distressed, and (c) the wife was not depressed and both spouses were maritally distressed. To the extent they made maladaptive attributions, wives displayed less positive behavior and more negative behavior. Husbands' attributions and behavior were unrelated, and associations between attributions and behavior were not moderated by marital distress and depression. These results highlight the need to clarify how partner behavior contributes to the attributions spouses make and to reexamine interventions designed to modify attributions in marital therapy. 相似文献
990.
Recent studies have provided new insights into the visuomotor functions of the dorsal and ventral regions of the lateral pre-motor cortex. Anatomical and physiological investigations in non-human primates have demonstrated that these regions have differing patterns of cortical connectivity and distinctive neuronal responses. Brain-imaging techniques and lesion studies have begun to probe the functions of homologous regions in humans. 相似文献