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981.
982.
Paula J. Durlach 《Psychopharmacology》1998,140(1):116-119
There is little evidence concerning the effects of caffeine in doses typical of one cup of tea. The present study investigated
the effect of 60 mg caffeine, consumed in either tea or hot water, on performance on a subset of the CANTAB test battery.
Eight males participated in a practice session and four test sessions. In each test session, the participant consumed a different
hot beverage and then, over approximately 90 min, completed nine tests from the CANTAB battery. The four beverages were created
by crossing beverage identity (tea or hot water) and caffeine dose (0 or 60 mg). Significant speeding of reaction time by
caffeine consumption was found in pattern recognition, delayed match to sample, and match to sample visual search. The effect
on reaction time of 60 mg caffeine can be detected, and may be evident within minutes of consumption.
Received: 16 March 1998/Final version: 27 July 1998 相似文献
983.
Dermatitis in bulb growers 总被引:2,自引:0,他引:2
Derk P. Bruynzeel Edith M. de Boer Elly J. Brouwer Frederik A. de Wolff Peter de Haan 《Contact dermatitis》1993,29(1):11-15
A damaged skin forms a health hazard in flower-bulb growers as it enables higher permeation rates For pesticides than normal skin. Therefore, an investigation was performed into the skin condition of 103 bulb growers and 49 controls. Contact dermatitis of the hands was of the same order (11 and 10%) in both groups. However, minor signs of dermatitis were seen more often in bulb growers (30 versus 8%, p <0.05). Most growers had contact with narcissus sap during the investigation. This irritant sap, as well as many other skin contacts with irritants such as hyacinth dust and pesticides, seemed to be responsible for many skin complaints. Contact serialization was suspected in 19 growers and 3 controls. Patch tests showed that contact sensitization existed to pesticides in probably 10, and to flower-bulb extracts in 4 growers. Reactions to propachlor were not regarded as very reliable as the test concentration seemed to be marginally irritant. There were only a few allergic reactions to narcissus (3) and tulip (2) and none to hyacinth. This investigation showed that minor irritant contact dermatitis was frequent in bulb growers, and indicated that contact sensitization to pesticides and bulbs seemed to be a less frequent but important cause of dermatitis. 相似文献
984.
de Boer A; Schroder C; Reddingius R; Willems H; Monnens L 《Nephrology, dialysis, transplantation》1998,13(9):2348-2350
Background: The passage of proteins across the
glomerular filtration barrier is mainly determined by the size of the
protein. In nephrotic syndrome (NS) the glomerular permselectivity is
affected, causing proteinuria. Some authors suggest the existence of a
generalized basement membrane defect. The permeability characteristics of
the peritoneal basement membrane in children with NS are not known.
Methods: The transperitoneal transport of proteins
with a different molecular weight ({beta}2-microglobulin MW 11 800 D,
albumin MW 69 000 D, IgG MW 160 000 D, and &agr;2-macroglobulin MW 820
000 D) was studied in a study group (group A) consisting of six stable
nephrotic children (three with glomerulosclerosis and three with congenital
nephrotic syndrome, one of them with mesangial sclerosis) and compared to a
control group (group B) consisting of eight stable children on peritoneal
dialysis. After a dwell of 6 h with Dianeal 1.36% dialysate and serum
samples were collected. For each patient the dialysate to plasma (D/P)
ratio of the four proteins were calculated. The D/P ratios of the nephrotic
patients in group A were compared to the D/P ratios of the patients in the
control group B. Data were expressed as mean ±SD.
Results: The values for the D/P ratios (in percentage)
of {beta}2-microglobulin, albumin, IgG and &agr;2-macroglobulin in
group A were 19.6±9.9, 2.7±1.7, 1.6±0.9,
and 0.5±0.4, compared to 24.9±10.2,
4.0±2.3, 2.2±1.2, and 0.7±0.3 in the
control group B. The ratios were plotted against MW on a double logarithmic
scale. In all patients a linear relationship between molecular weight and
D/P ratio of the proteins was obtained. The D/P ratios of the study group
did no differ significantly from the control group.
Conclusion: We conclude that the size selectivity of
the capillary permeability is not affected in the peritoneal membrane in
children with NS due to glomerulosclerosis and congenital nephrotic
syndrome. 相似文献
985.
ABSTRACT: Nigeria generally has overlooked the health needs of its adolescents. To determine student perceptions of their health-related needs, some 600 students in Uyo, the capital of Akwa Ibom State, were surveyed, and they identified several concerns. Their responses provided the basis to offer five recommendations for action: improve the quality of school health service facilities and personnel available in the secondary schools; implement a comprehensive national program of drug education and control; provide a healthful school environment; assess the quality and quantity of food provided to students, especially in boarding schools; and implement a comprehensive school health education program in Nigerian schools. 相似文献
986.
987.
Randomised trial comparing the upright and supine positions for the second stage of labour 总被引:2,自引:1,他引:1
P. R. de Jong Senior Specialist R. B. Johanson Senior Lecturer P. Baxen Chief Professional Nurse V. D. Adrians Senior Professional Nurse S. van der Westhuisen Lecturer P. W. Jones Professor 《BJOG : an international journal of obstetrics and gynaecology》1997,104(5):567-571
Objective To assess the maternal and neonatal effects of upright compared with recumbent positions during delivery, in terms of defined outcome variables.
Design A randomised controlled trial.
Setting St Monica's Nursing Home, a midwife based maternity unit in Cape Town, South Africa.
Participants Five hundred and seventeen women of low obstetrical risk assigned to deliver at the nursing home.
Results The trial showed that women who adopted the upright posture for delivery experienced less pain, perineal trauma and fewer episiotomies than those who delivered in the supine position.
Conclusion The data suggest that in women of low obstetrical risk, choice of posture during delivery may be encouraged. 相似文献
Design A randomised controlled trial.
Setting St Monica's Nursing Home, a midwife based maternity unit in Cape Town, South Africa.
Participants Five hundred and seventeen women of low obstetrical risk assigned to deliver at the nursing home.
Results The trial showed that women who adopted the upright posture for delivery experienced less pain, perineal trauma and fewer episiotomies than those who delivered in the supine position.
Conclusion The data suggest that in women of low obstetrical risk, choice of posture during delivery may be encouraged. 相似文献
988.
Endoscopic Sphincterotomy and Biliary Drainage in Patients with Cholangitis Due to Common Bile Duct Stones 总被引:13,自引:0,他引:13
989.
Laura Santambrogio Maria Lipartiti Alessandro Bruni Roberto Dal Toso 《Journal of neuroimmunology》1993,45(1-2)
The presence of functional dopamine receptors on differentiated cells of the mammalian immune system is still under discussion. This study has utilized (-)-[3H]sulpride as a ligand to detect the presence of recognition sites of the dopamine D2 receptor family on human T- and B-lymphocytes. The (-)-[3H]sulpiride binding was of high affinity (Kd 0.9 nM ± 0.2 nM, specific, saturable (Bmax 10.2 ± 1.4 fmol/106 cells) and reversible. The pharmacological characterization of the recognition site suggests, similarities mainly with the D2 and D4 rather than D3 subtype of dopamine receptor. Furthermore, dopamine treatment was able to reduce the intracellular cAMP levels of lymphocytes stimulated with forskolin, thus suggesting a potential functional significance of this dopamine receptor in mediating neural-immune interactions. 相似文献
990.
Summary We report two cases of Creutzfeld-Jakob disease with clusters of giant collagen fibers. To our knowledge, these abnormally large collagen fibers have never been described in patients with degenerative diseases of the central nervous system. The significance of the formation of such plaque-like large collagen fibers has as yet not been elucidated. It is felt that these represent a product of the degenerative process.Presented in part at the 68th Annual Meeting of the American Association of Neuropathologists, St. Louis, Missouri, June 18–21, 1992 相似文献