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51.
52.
Julie N Hook Bruno Giordani David E Schteingart Kenneth Guire Jodie Giles Kelley Ryan Stephen S Gebarski Scott A Langenecker Monica N Starkman 《Journal of the International Neuropsychological Society》2007,13(1):21-29
Chronically elevated levels of cortisol have been associated with changes in cognitive functioning and brain morphology. Using Cushing's disease as a model to assess the effects of high levels of cortisol on cognitive functioning, 27 patients with Cushing's disease were examined at baseline and three successive follow-up periods up to 18 months after successful surgical treatment. At all follow-up periods, patients were administered cognitive tests as well as measures of plasma and urinary free cortisol. Structural MRIs and a depression measure were taken at baseline and one-year follow-up. Results showed that there is a specific pattern of significant cognitive and morphological improvement following successful treatment. Verbal fluency and recall showed recovery, although brief attention did not. Age of participants was a significant factor as to when recovery of function occurred; younger patients regained and sustained their improvement in cognitive functioning more quickly than older participants. Improvement in verbal recall also was associated with a decrease in cortisol levels as well as an increase in hippocampal formation volume one year after treatment. Overall, these findings suggest that at least some of the deleterious effects of prolonged hypercortisolemia on cognitive functioning are potentially reversible, up to at least 18 months post treatment. 相似文献
53.
Northern Ireland has one of the lowest breastfeeding initiation rates in the world. Given that attitudes toward infant feeding are formed at an early age and a high rate of teenage pregnancy, it has become necessary to survey attitudes to infant feeding and breastfeeding promotion preferences in teenagers in Northern Ireland. Questionnaires were distributed to teenagers aged 14 to 18 years (n = 419) based in 7 schools selected by type and location throughout Northern Ireland. Attitudes to breastfeeding in public reflected preferred infant-feeding method and were positively influenced by prior exposure to breastfeeding (P = .024). Females were more positive than males both in relation to breastfeeding in public (P = .002) and breastfeeding promotion (P = .003). Recommendations for breastfeeding promotion include specific targeting of young people (both male and female) and enabling contact between teenagers and nursing mothers as much as possible. 相似文献
54.
55.
Diabetic autonomic neuropathy in BB rats and effect of ARI treatment on heart-rate variability and vagus nerve structure 总被引:1,自引:0,他引:1
The preventive effect of the aldose reductase inhibitor (ARI) ponalrestat on heart-rate variability and the development of autonomic neuropathy in the vagus nerve was investigated in the spontaneously diabetic BB rat. ARI treatment completely prevented the characteristic decrease in heart-rate variability and axonal atrophy of the vagus nerve for 4 mo in hyperglycemic BB rats. After 6 mo of treatment, the preventive effect on heart-rate variability was partial, and the vagus nerve demonstrated an increase in regenerating myelinated and unmyelinated fibers. These data suggest that autonomic neuropathy involving the vagus nerve is metabolically induced by demonstrating that inhibition of the polyol pathway significantly delays the occurrence of functional and structural autonomic neuropathy despite the presence of hyperglycemia. 相似文献
56.
Najet Rebai Guillermina Almazan Ling Wei Mark I. Greene H. Uri Saragovi 《The European journal of neuroscience》1996,8(2):273-281
A surface receptor complex of M r ˜65 000 (p65) and ˜95 000 (p95) is expressed in cells of the central nervous system of mice. This receptor is recognized by monoclonal antibody 87.92.6 or by reovirus type 3 haemagglutinin as unnatural ligands. The p65/p95 receptor is expressed mostly in neural embryonic precursors undergoing proliferation, especially those in the S-G2 phase of the cell cycle. Receptor expression decreases progressively throughout embryogenesis to low but detectable levels in the adult brain. Biochemical characterization revealed that the neural p65/p95 receptor complex is indistinguishable from the p65/p95 receptor expressed in T cells, where receptor ligation leads to a mitogenic block. In neural and lymphoid tissues the p65/p95 receptor (or an associated protein) possesses a tyrosine kinase enzymatic activity. Receptor ligation in neural cells resulted in the rapid tyrosine phosphorylation of cellular proteins which are different from substrates phosphorylated in T cells. Differential substrate coupling to the receptor may account for differences in signal transduction and biology between neural cells and T cells. Further study of this receptor complex may help define important features of neural proliferation, differentiation and survival. 相似文献
57.
Summary The fractional clearance of lithium (CLLi/CLcr) calculated in 15 normal healthy adults from a single morning urine aliquot collection, together with a single venous blood
sample (FQ) was compared with the average CLLI/CLCR obtained from three timed consecutive urine collections with mid-point blood sampling (FABC). Lithium had been ingested 15–18
h prior to the collection of these samples.
Mean CLLi/CLCR was similar (FQ, 0.186, FABC, 0.177), with a highly significant correlation in each individual of CLLI/CLSR measured by either method (r = 0.97,P 0.0001).
Proximal tubular reabsorption of sodium using lithium clearance may be calculated from a single urine and blood sample. 相似文献
58.
Uveitis in childhood--Part III. Posterior 总被引:1,自引:0,他引:1
C L Giles 《Annals of ophthalmology》1989,21(1):23-28
Toxoplasma, nematodes, and cytomegalovirus are the most common causes of uveitis in children involving the posterior pole. Discussion of treatment and management is detailed. Rubella retinitis and subacute sclerosing panencephalitis are specific entities which are limited in their initial presentation in children. Panuveitis including sympathetic ophthalmia, Vogt-Koyanagi-Harada, and Beh?et's syndromes, while relatively rare in their occurrence, demand early treatment intervention. Specific antimicrobial therapy and adrenocorticosteroids as well as therapeutic suggestions are also included. This is the last part of a three-part series of articles. 相似文献
59.
Objectives/Hypothesis: Numerous mechanical animal models for the creation of otitis media with effusion (OME) have been described since the 1920s. However, there are many problems associated with these models, including high infection rates, unreliability, and high resolution rates. The aim of the current study was to create a suitable mechanical animal model that would produce a sterile and long-lasting effusion. Study Design: A new technique using an external surgical approach on specific pathogen–free rats is described. Method: The eustachian tubes of 56 rats were obstructed in the mid portion along the skull base with gutta percha. Results: All animals developed an effusion within 1 week of the procedure. The resolution rate was 8%, with 80% maintaining sterile effusions for up to 1 year. Conclusions: This new procedure for an OME model has proved consistently reliable in creating a persistent and long-lasting effusion. It has a low infection rate and should benefit future studies on the prolonged effects of OME on the tympanic membrane and middle ear. 相似文献
60.
The differences in both the biology of pregnancy and the content of routine care between gravidas with and without diabetes mellitus lead to important differences in the potential utility of both ultrasound examination and maternal serum alpha-fetoprotein (MSAFP) screening. However, both diagnostic methods have become standards of care for these patients, without critical evaluation. This study examines the utility of both ultrasound and MSAFP in diabetic women. Four hundred thirty-two women with diabetes mellitus antedating pregnancy were examined sonographically between 12-23 weeks' gestation. Of these, 393 were also screened with MSAFP determinations. At delivery, 32 of these fetuses were found to have 38 major congenital malformations. All fatal or potentially life-threatening defects had been diagnosed in utero by sonography before 24 weeks' gestation. Ultrasound had a positive predictive value of 90% and a negative predictive value of 97% for identification of major birth defects before 24 weeks' gestation. There were 14 MSAFP values greater than 2.0 multiples of the median, and nine of these patients elected to undergo amniocentesis. Maternal serum alpha-fetoprotein screening had a positive predictive value of 17% and a negative predictive value of 94%. No malformations were detected through MSAFP screening that had not been diagnosed by sonography. No malformations missed sonographically were detected by MSAFP screening, and none of the amniocenteses were helpful diagnostically. We conclude that MSAFP screening is of minimal utility for diagnosing major congenital malformations in a high-risk population examined universally by an experienced sonographer. 相似文献