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951.
DB Matthews LL Devaud JM Fritschy W Sieghart AL Morrow 《Canadian Metallurgical Quarterly》1998,70(3):1160-1166
Previous research has shown that chronic ethanol consumption dramatically alters GABA(A) receptor alpha1 and alpha4 subunit gene expression in the cerebral cortex and GABA(A) receptor alpha1 and alpha6 subunit gene expression in the cerebellum. However, it is not yet known if chronic ethanol consumption produces similar alterations in GABA(A) receptor gene expression in other brain regions. One brain region of interest is the hippocampus because it has recently been shown that a subset of GABA(A) receptors in the hippocampus is responsive to pharmacologically relevant concentrations of ethanol. Therefore, we directly compared the effects of chronic ethanol consumption on GABA(A) receptor subunit gene expression in the hippocampus and cerebral cortex. Furthermore, we investigated whether the duration of ethanol consumption (14 or 40 days) would influence regulation of GABA(A) receptor gene expression in these two brain regions. Chronic ethanol consumption produced a significant increase in the level of GABA(A) receptor alpha4 subunit peptide in the hippocampus following 40 days but not 14 days. The relative expression of hippocampal GABA(A) receptor alpha1, alpha2, alpha3, beta(2/3), or gamma2 was not altered by either period of chronic ethanol exposure. In marked contrast, chronic ethanol consumption for 40 days significantly increased the relative expression of cerebral cortical GABA(A) receptor alpha4 subunits and significantly decreased the relative expression of cerebral cortical GABA(A) receptor alpha1 subunits. This finding is consistent with previous results following 14 days of chronic ethanol consumption. Hence, chronic ethanol consumption alters GABA(A) receptor gene expression in the hippocampus but in a different manner from that in either the cerebral cortex or the cerebellum. Furthermore, these alterations are dependent on the duration of ethanol exposure. 相似文献
952.
The low density lipoprotein receptor-related protein (LRP) is a large endocytic receptor that binds multiple ligands and is highly expressed in neurons. Several LRP ligands, including apolipoprotein E/lipoproteins and amyloid precursor protein, have been shown to participate either in Alzheimer's disease pathogenesis or pathology. However, factors that regulate LRP expression in neurons are unknown. In the current study, we analyzed the effects of nerve growth factor (NGF) treatment on LRP expression, distribution, and function within neurons in two neuronal cell lines. Our results show that NGF induces a rapid increase of cell surface LRP expression in a central nervous system-derived neuronal cell line, GT1-1 Trk, which was seen within 10 min and reached a maximum at about 1 h of NGF treatment. This increase of cell surface LRP expression is concomitant with an increase in the endocytic activity of LRP as measured via ligand uptake and degradation assays. We also found that the cytoplasmic tail of LRP is phosphorylated and that NGF rapidly increases the amount of phosphorylation. Furthermore, we detected a significant increase of LRP expression at the messenger RNA level following 24 h of NGF treatment. Both rapid and long term induction of LRP expression were also detected in peripheral nervous system-derived PC12 cells following NGF treatment. Taken together, our results demonstrate that NGF regulates LRP expression in neuronal cells. 相似文献
953.
S Moscarella G Buzzelli RG Romanelli M Monti C Giannini G Careccia EM Marrocchi AL Zignego 《Canadian Metallurgical Quarterly》1998,18(5):366-369
The prevalence of Helicobacter pylori (HP) IgG antibodies was analysed in a group of 142 asymptomatic children (group A) and in 31 pediatric patients (group B) with recurrent abdominal pain. HP IgG antibodies were measured by a commercially available fluorescence-enzyme immuno-assay test (Heloritest IgG, Fa Eurospital). In asymptomatic children the prevalence of HP IgG antibodies increased significantly with age from 17% with 6 years to more then 40% with 14 years. A higher prevalence of HP IgG antibodies was found in children living in more crowded housing conditions. Comparing the number of HP IgG positive children in group B (58%) to a matched population from group A (35%) no statistically different prevalence rates were found. Thus HP IgG antibodies are found in similar frequencies, in both, symptomatic and asymptomatic children. Therefore the presence of HP-IgG antibodies does not necessarily indicate that the HP infection is the cause for the recurrent abdominal pain in these children. 相似文献
954.
MH Maor LB North FF Cabanillas AL Ames MA Hess JD Cox 《Canadian Metallurgical Quarterly》1998,41(3):647-650
PURPOSE: To review the long-term clinical effects of unilateral kidney irradiation on overall renal function and blood pressure in patients with gastric lymphoma. METHODS AND MATERIALS: In the study were 27 patients with Stage I or II gastric lymphoma who had undergone irradiation of at least 24 Gy to > or = 1/3 of the left kidney. They include 16 women and 11 men, aged 31 to 77, with a mean age of 57.6 years (median 56). Fifteen patients had Stage I and 12 had Stage II disease. In 13 patients the whole kidney had been irradiated, and 14 had had partial kidney irradiation, at doses ranging between 24 and 40.5 Gy. All patients received combined chemotherapy with various drugs: all patients received corticosteroids, and five received cis-platinum. Their follow-up ranged between 0.7 and 7.8 years (mean 3.4 years). Data on possible effects of the treatment on blood pressure, renal function as assessed by blood urea and creatinine, and kidney shrinkage as seen by serial computed tomography scanning were collected on all patients. RESULTS: Three patients had persistent, mild elevations of urea and creatinine levels, which did not require special treatment. All three also received cis-platinum. Ipsilateral kidney shrinkage was evident in most patients. In 19 patients the craniocaudal measurement of the kidney shrank by > or = 1.6 cm. Shrinkage in other dimensions was also evident. The degree of atrophy was related to the volume of kidney irradiated. Only two patients developed hypertension, both at a low level of 150/90; one patient had had 40 Gy to the whole kidney, the other 40 Gy to half the kidney. Neither patient had elevated urea or creatinine. CONCLUSIONS: Notwithstanding the shrinkage to the irradiated part of the kidney, the treatment did not lead to clinically significant hypertension or renal dysfunction. The administration of cis-platinum to patients with gastric lymphoma that requires kidney irradiation should be further evaluated. 相似文献
955.
SR Simon TH Lee L Goldman AL McDonough SD Pearson 《Canadian Metallurgical Quarterly》1998,13(12):836-838
In many settings, primary care physicians have begun to delegate inpatient care to hospitalists, but the impact of this change on patients' hospital experience is unknown. To determine the effect on physician-patient communication of having the regular outpatient physician (continuity physician) continue involvement in hospital care, we surveyed 1,059 consecutive patients hospitalized with chest pain. Patients whose continuity physicians remained involved in their hospital care were less likely to report communication problems regarding tests (20% vs 31%, p =.03), activity after discharge (42% vs 51%, p =.02), and health habits (31% vs 38%, p =. 07). In a setting without a designated hospitalist system, communication problems were less frequent among patients whose continuity physicians were involved in their hospital care. New models of inpatient care delivery can maintain patient satisfaction but to do so must focus attention on improving physician-patient communication. 相似文献
956.
Dinov I.D. Mega M.S. Thompson P.M. Woods R.P. Sumners D.L. Sowell E.L. Toga A.W. 《IEEE transactions on information technology in biomedicine》2002,6(1):73-85
In the field of template-based medical image analysis, image registration and normalization are frequently used to evaluate and interpret data in a standard template or reference atlas space. Despite the large number of image-registration (warping) techniques developed recently in the literature, only a few studies have been undertaken to numerically characterize and compare various alignment methods. In this paper, we introduce a new approach for analyzing image registration based on a selective-wavelet reconstruction technique using a frequency-adaptive wavelet shrinkage. We study four polynomial-based and two higher complexity nonaffine warping methods applied to groups of stereotaxic human brain structural (magnetic resonance imaging) and functional (positron emission tomography) data. Depending upon the aim of the image registration, we present several warp classification schemes. Our method uses a concise representation of the native and resliced (pre- and post-warp) data in compressed wavelet space to assess quality of registration. This technique is computationally inexpensive and utilizes the image compression, image enhancement, and denoising characteristics of the wavelet-based function representation, as well as the optimality properties of frequency-dependent wavelet shrinkage 相似文献
957.
Recently few cases as to female genital tuberculosis were reported, therefore it is considered that the incidence of the female genital tuberculosis was decreased. However it is important to make a right diagnosis of tuberculosis, because the tuberculosis in the female sexual organs is one of the factors of female sterility. The diagnosis is needed to examine bacteriologically or pathologically. The diagnosed genital tract or pelvic tuberculosis was treated by anti-tuberculosis chemotherapy firthtly and by surgical procedures in case of necessity. 相似文献
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