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991.
From studies in 43 patients (17 male, 26 female, mean age 51 years), we compared the analysis of the routine complete "24-hr" ambulatory esophageal pH monitoring study to that of the 16-hr overnight interval (4:00 PM to 8:00 AM). The latter included a major meal with an upright postprandial period and a recumbent period. All patients were monitored for at least 20 hr (median = 22.6 hr). The percent distal esophageal pH less than 4.0 and number of reflux episodes were measured for the total, upright, and recumbent periods of both the 16-hr and "24-hr" monitoring times. Significant (P less than 0.001) positive correlations were found for all comparisons between the two monitoring periods including percent time of pH less than 4.0 (total: r = 0.98; upright: r = 0.96) and number of episodes (totals r = 0.97; upright: r = 0.93). Patients were separated into normal and abnormal refluxers based on results of "24-hr" monitoring (pH below 4.0 greater than 4.2% total time; greater than 6.0% upright; greater than 1.2% recumbent). Based on this, sensitivity and specificity for 16-hr monitoring were as follows: total study: 86% and 95%; upright: 80% and 91%; recumbent: 100% for both. Conclusions: (1) a 16-hr overnight pH monitoring period can provide a reliable representation of "24-hr" distal esophageal acid exposure, (2) this shorter monitoring may improve patient acceptability and compliance, and (3) the symptom index was changed in 26.3% of patients using the 16-hr evaluation. 相似文献
992.
Hirohisa Miyake Patrick O. Eghwrudjakpor Takashi Sakamoto Koreaki Mori 《Child's nervous system》1992,8(5):243-246
Experimental hydrocephalus was induced in rats by intracisternal injection of kaolin suspension. The amounts of norepinephrine and dopamine were determined in the whole brain and specific brain regions at 1 week (acute phase) and 4 weeks (chronic phase). The turnover of catecholamine, an index of the activity of catecholamine-containing neurons, was determined by measuring the decrease in catechlamine contents 2 h after intraperitoneal injection of -methyl-p-tyrosine (250 mg/kg), an inhibitor of tyrosine hydroxylase. We observed that the catecholamine contents in kaolin-induced hydrocephalus were not significantly different from control values. Following injection of -methyl-p-tyrosine, there was decrease in levels of catecholamines in both control and hydrocephalic rats. This decrease was, however, significantly less in induced hydrocephalus than in control animals. This result suggested that in hydrocephalus, the activities of norepinephrinergic and dopaminergic neurons are reduced. 相似文献
993.
Linda Shaw Michael Jeremy Shaw Thomas Donald Foster 《Community dentistry and oral epidemiology》1989,17(4):187-189
Although there is relatively little information concerning the oral health of handicapped adults there is increasing evidence to suggest that their oral condition, particularly periodontal health, is poor. The present investigation involved assessment of 382 handicapped patients attending four different Adult Training Centres in Birmingham. The caries status, oral hygiene, and periodontal conditions were evaluated and the Community Periodontal Index of Treatment Need (CPITN) was calculated. In order to assess the manual dexterity and the comprehension of the trainees a standard test was devised. This consisted of timing each participant in carrying out simple instructions to pick up and position certain common objects. The results indicated high levels of plaque, calculus, and bleeding with a mean CPITN of 7.43. The mean time taken for the manual dexterity and comprehension test was 23.9 seconds with a range from 10 to 80 seconds, S.E.+/- 1.33. This compares with results from 34 "normal" adults of a mean time of 8.2 seconds +/- 1.8 with a range of 6 to 12 seconds. There was no significant correlation between the Manual Dexterity and Comprehension scores and the periodontal indices in the handicapped adults. 相似文献
994.
Hay DP 《Convulsive therapy》1989,5(1):8-16
Treatment with electroconvulsive therapy (ECT) of medically ill geriatric patients with affective disorders is described. Of 135 patients to whom ECT was administered in 6 years, 55% were over 60 years of age. One-third (45) exhibited cardiovascular (62%), central nervous system (15%), or other medical conditions (22%) increasing the risks of the treatment. Treatment strategies are described. 相似文献
995.
A knowledge-based Hypertext of Pathology integrating videodisc-based images and computer-generated graphics with the textual cognitive information of an undergraduate pathology curriculum has been developed. The system described in this paper was implemented under HyperCard00 during 1988 and 1989. Three earlier versions of the system that were developed on different platforms are contrasted with the present system. Strengths, weaknesses, and future extensions of the system are enumerated. The conceptual basis and organizational principles of the knowledge base are also briefly discussed. 相似文献
996.
Donald L. Phillips James L. Pirkle Virlyn W. Burse John T. Bernert Jr. L. Omar Henderson Larry L. Needham 《Archives of environmental contamination and toxicology》1989,18(4):495-500
Twenty healthy adult humans had serum samples drawn on four occasions within a 24-hr period: after a 12 hr overnight fast, 4–5 hr after a high fat breakfast, at midafternoon, and the next morning after another 12 hr fast. Nonfasting samples had 22% to 29% higher mean concentrations (p < 0.05) than did fasting samples for polychlorinated biphenyls (PCBs, 4.81 vs 3.74 ng/g serum wt), hexachlorobenzene (HCB, 0.163 vs 0.134 ng/g serum wt), andp,p-dichlorodiphenyldichloroethylene (p,p-DDE, 6.74 vs 5.37 ng/g serum wt) measured by electron capture gas liquid chromatography. Total serum lipids were estimated from measurements of total cholesterol, free cholesterol, triglycerides, and phospholipids and were 20% higher in nonfasting samples than in fasting samples (7.05 g/L vs 5.86 g/L). When PCBs, HCB, andp,p-DDE concentrations were corrected by total serum lipids, results from fasting and nonfasting samples were not statistically different. Because of the differences in these chlorinated hydrocarbon concentrations observed with different sample collection regimens, meaningful comparison of analytical results requires standardizing collection procedures or correcting by total serum lipid levels. 相似文献
997.
Current models hold that CD4+ depletion occurs as a result of direct and indirect effects of HIV, which both kill peripheral CD4+ cells and prevent adequate regeneration. Although age-associated involution diminishes thymic reserve and HIV is clearly thymotoxic, clinical trials have nonetheless shown that large proportions of patients who sustain adequate control of viral replication with highly active antiretroviral therapy (HAART) will demonstrate some evidence for thymic-dependent immune reconstitution, which is associated with improved immune competence. Furthermore, patients with insufficient or absent immune reconstitution following HAART generally lack evidence for thymopoiesis. Current studies are focused on improving our understanding of the causes for thymic failure in HIV infection. Recent work has demonstrated that some HIV strains, especially those that are CXCR4 trophic, are more thymotoxic and may contribute to irreversible thymic damage in this population. 相似文献
998.
Porter JD Merriam AP Leahy P Gong B Feuerman J Cheng G Khanna S 《Human molecular genetics》2004,13(3):257-269
999.
The α1β1 and α2β1 Integrins Provide Critical Support for Vascular Endothelial Growth Factor Signaling, Endothelial Cell Migration, and Tumor Angiogenesis 总被引:3,自引:0,他引:3 下载免费PDF全文
Donald R. Senger Carole A. Perruzzi Michael Streit Victor E. Koteliansky Antonin R. de Fougerolles Michael Detmar 《The American journal of pathology》2002,160(1):195-204
Angiogenesis is a complex process, involving functional cooperativity between cytokines and endothelial cell (EC) surface integrins. In this study, we investigated the mechanisms through which the alpha(1)beta(1) and alpha(2)beta(1) integrins support angiogenesis driven by vascular endothelial growth factor (VEGF). Dermal microvascular EC attachment through either alpha(1)beta(1) or alpha(2)beta(1) supported robust VEGF activation of the Erk1/Erk2 (p44/42) mitogen-activated protein kinase signal transduction pathway that drives EC proliferation. Haptotactic EC migration toward collagen I was dependent on alpha(1)beta(1) and alpha(2)beta(1) as was VEGF-stimulated chemotaxis of ECs in a uniform collagen matrix. Consistent with the functions of alpha(1)beta(1) and alpha(2)beta(1) in supporting signal transduction and EC migration, antibody antagonism of either integrin resulted in potent inhibition of VEGF-driven angiogenesis in mouse skin. Moreover, combined antagonism of alpha(1)beta(1) and alpha(2)beta(1) substantially reduced tumor growth and angiogenesis of human squamous cell carcinoma xenografts. Collectively, these studies identify critical collaborative functions for the alpha(1)beta(1) and alpha(2)beta(1) integrins in supporting VEGF signal transduction, EC migration, and tumor angiogenesis. 相似文献
1000.
Harned MS Ormerod AJ Palmieri PA Collinsworth LL Reed M 《Journal of occupational health psychology》2002,7(2):174-188
Although sexual assault by workplace personnel is widely viewed as a type of sexual harassment, little is known about whether these overlapping constructs may possess some unique characteristics. This article compares the theoretical antecedents and consequences of sexual assault by workplace personnel and other types of sexual harassment among 22,372 women employed in the U.S. military. Path analysis revealed that low sociocultural and organizational power are associated with an increased likelihood of both types of victimization. Organizational climate and job gender context are directly associated with sexual harassment but are only indirectly associated with sexual assault by workplace personnel. Both types of victimization are associated with a variety of negative outcomes, but the pattern of negative consequences differs. 相似文献