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51.
52.
There is considerable evidence that sex differences in spatial ability exist in adults, with males outperforming females at every age after puberty. It is difficult, however, to find sex differences in children younger than 13. This is due in part to the lack of adequate measures of spatial ability for use with children. We report the use of spatial tests for children that are similar to those that have shown large sex differences in adults and may be measuring ability comparable to adult spatial ability. Four tests of mental rotation and spatial visualization were given to two samples of children. The first sample consisted of 81 children (39 males and 42 females) aged 9 to 12 years. The second sample consisted of 42 children (21 males and 21 females) aged 9 to 13 years. Sex differences of .4–.6 standard deviations were found on three tests in both samples. These results indicate that sex differences in spatial ability can be found in preadolescents if appropriate tests are used. Measurement of these abilities in children facilitates the investigation of possible biological and sociocultural contributors to the sex differences in spatial ability.This study was supported by National Institutes of Health Grant HD19644 and NIH Biomedical Research Support Grant S07 RR05366-24. 相似文献
53.
Does increased intracranial pressure in patients with pseudotumour cerebri PTC result in cognitive impairments The results of previous investigations have not clarified this question It may be that there is a subgroup within those diagnosed with PTC that does experience cognitive decline with increased intracranial pressure However elevated intracranial pressure headache and emotional distress also can contribute to reduced cognitive performance and increased self monitoring As a result of the lack of clarity regarding the impact of PTC on cognition clinicians are left with no empirically derived practice guidelines A case study demonstrates subjective complaints of concentration and memory deficits in a depressed patient with PTC whose neuropsychological stores except Seashore Rhythm Test were in the normal range 相似文献
54.
Carl Andrew Castro John B. Hogan Kimberly A. Benson Christina W. Shehata Michael R. Landauer 《Pharmacology, biochemistry, and behavior》1995,50(4):521-526
Experimental drugs and compounds that do not easily dissolve in water or saline are frequently combined with vehicles like solvents, detergents, or vegetable oils. Yet very little has been reported on the behavioral effects of vehicles. In this study, we assessed the effects of a vegetable oil (emulphor-620), two detergents (Tween-20 and Tween-80), and two solvents [dimethyl sulphoxide (DMSO) and ethanol] on the locomotor activity in CD2F1 male mice. Locomotor activity was monitored for 12 h after vehicle administration (IP). The concentrations for each vehicle were expressed as percent of vehicle in saline (v/v). Emulphor-620 did not affect locomotor activity at any concentration tested (2%, 4%, 8%, 16%, and 32%). Tween-20 significantly decreased locomotor activity at a concentration of 16% and Tween-80 at 32%. DMSO significantly decreased locomotor activity at concentrations of 32% and 64%. In contrast, ethanol produced a biphasic behavioral response: increased activity at a concentration of 16% and decreased activity at a concentration of 32%. These results will facilitate the selection and concentration of vehicles to be used in combination with experimental drugs or test agents. 相似文献
55.
56.
Detection of Trichomonas vaginalis in pregnant women with the InPouch TV culture system. 总被引:18,自引:2,他引:16
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D Draper R Parker E Patterson W Jones M Beutz J French K Borchardt J McGregor 《Journal of clinical microbiology》1993,31(4):1016-1018
Trichomonas vaginalis causes a common genitourinary infection which is frequently asymptomatic. At present, pregnant women are not usually screened for the infection unless they are symptomatic. In the present study, we screened and obtained samples for culture from all pregnant women attending a prenatal clinic with the InPouch TV culture system and compared results with those of standard culture in Diamond's medium and slide wet mount examination. The InPouch TV culture system was as reliable as Diamond's medium in detecting T. vaginalis and may be useful and effective in a pregnancy clinic setting. 相似文献
57.
58.
Platelet satellitism: experimental studies 总被引:3,自引:0,他引:3
D H McGregor J W Davis P I Liu E Gates A R Poindexter 《Laboratory investigation; a journal of technical methods and pathology》1980,42(3):343-355
Platelet satellitism (PS), the in vitro phenomenon of platelets rosetting about nonlymphocytic leukocytes, is an uncommon and poorly understood finding reported in the ethylenediaminetetra-acetic acid (EDTA)-anticoagulated blood of patients with a wide variety of clinical conditions. This report presents experimental studies investigating the nature of this phenomenon by utilizing the blood of patients with platelet satellitism. Wet preparation studies and electron microscopy (transmission and scanning) demonstrated the morphologic sequences involved in the phenomenon, including eventual phagocytosis of platelets by neutrophils. The results of varying conditions such as time, temperature, and anticoagulant are described. All of five patients tested were found to have cryofibrinogenemia. Certain blood components from all of three patients tested were capable of inducing PS in normal whole blood, whereas components from normal subjects usually were not. In one patient (A), the PS-inducing capability appeared to be present in both plasma and platelets. In another patient (B) the PS-inducing capability was present in platelets (in both 1966 and 1975) and also in the cryosupernate of serum and plasma; among various antisera, antifibrinogen had the greatest ability to reduce the degree of PS in patient blood; addition of moderate amounts of CaCl2 and/or MgCl2 did not diminish the phenomenon; and two sisters and two daughters demonstrated no PS. In a third patient (C) the PS-inducing capability appeared to be largely concentrated in the cryoprecipitable fraction of plasma. These studies suggest that there are different factors in the patients' blood resulting in PS. Further studies showed PS could be induced in normal blood by adding certain nonprimate antihuman antisera (anti-IgM, antialbumin or antifibrinogen) and also by adding some preparations of normal washed platelets to the same individuals's normal whole blood. This indicates that the phenomenon of PS can be produced by factors other than those specifically present in patients with PS. Antigen-antibody complexes, either formed in vivo (mixed cryoglobulinemia) or in vitro, did not result in PS when mixed with normal blood. These and other studies suggest that PS can result from the presence of several different factors, usually proteins (in conjunction with EDTA), which probably attach to the surface of platelets apparently resulting in some alteration (such as change in surface charge) causing the platelets to be attracted to and phagocytosed by neutrophils. 相似文献
59.
Obstructive sleep apnea has traditionally been viewed as a structural disease. A multitude of systemic endocrine and cardiovascular abnormalities have been previously attributed to the prevalence of obesity in these patients. A growing body of clinical evidence, however, points to a relationship between sleep apnea and its systemic abnormalities independent of obesity. We hypothesize that this association is based on a maladaptive autonomic response of chemoreceptors, reacting to the hypoxia, hypercapnia, and acidosis of sleep apnea. The elevated sympathetic response triggers an inflammatory cascade that results in a myriad of downstream consequences including insulin resistance, hypertension, diabetes, atherosclerosis and metabolic syndrome. The sympathetic bias and endocrine disturbances may further exacerbate sleep disturbance in a potentially pernicious cycle. Our proposal may extend to any chronic respiratory or metabolic conditions that manifest hypoxia, hypercapnia, and acidosis and elicit a maladaptive autonomic and inflammatory response. 相似文献
60.
Analysis of the coxsackievirus B-adenovirus receptor gene in patients with myocarditis or dilated cardiomyopathy 总被引:1,自引:0,他引:1
Bowles NE Javier Fuentes-Garcia F Makar KA Li H Gibson J Soto F Schwimmbeck PL Schultheiss HP Pauschinger M 《Molecular genetics and metabolism》2002,77(3):257-259
Myocarditis and dilated cardiomyopathy (DCM) are common causes of morbidity and mortality in children and adults, most commonly due to infection with coxsackievirus B or adenovirus. Increased expression of the common human coxsackievirus B-adenovirus receptor (CAR) has been reported in patients with DCM. We investigated the CAR gene in patients with acquired or familial myocarditis/DCM for mutations/polymorphisms. Several polymorphisms or intronic substitutions, distant from the intron-exon boundaries, were identified but no mutations. Based upon these data it appears that CAR gene mutations are not a major host determinant in the development of myocarditis and DCM. 相似文献