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排序方式: 共有6717条查询结果,搜索用时 828 毫秒
111.
RB Singh H Mori J Chen S Mendis M Moshiri S Zhu SH Kim RG Sy AM Faruqui 《Canadian Metallurgical Quarterly》1996,3(6):489-494
PURPOSE: Two types of glass wool were used to remove leukocytes in semen for evaluation of reactive oxygen species production by spermatozoa in oligozoospermic patients with leukocytospermia. METHODS: Semen samples were prepared using fine-structure glass wool (SpermFertil) and coarse-structure glass wool. In each treatment group, native semen was evaluated for sperm concentration, percentage motility, viability, leukocyte concentration, and production of reactive oxygen species. RESULTS: Electron microscopically, SpermFertil showed a higher number of leukocytes attached to the fibers compared to coarse-structure glass wool. Leukocytes in native semen and after glass wool filtration as determined by peroxidase cytochemistry confirmed this observation. Reactive oxygen species decreased from 45.303 counts/10(7) viable cells in native semen to 15.806 counts/10(7) cells in coarse structure wool and 7.465 counts/10(7) cells in Spermfertil, respectively. CONCLUSIONS: Removal of leukocytes from semen of oligozoospermic patients by means of glass wool filtration is a useful method to distinguish production of reactive oxygen species by leukocytes versus sperm cells. 相似文献
112.
Tuberculous meningitis remains an important illness that can be difficult to diagnose in a timely fashion and carries significant morbidity. We present a retrospective review of the cases of tuberculous meningitis diagnosed and treated at a single institution. Fifty-eight cases were identified and stratified according to stage of disease at presentation. Four patients (7%) died; three (5%) developed severe neurological sequelae. Poor outcomes were largely confined to cases presenting in an advanced stage and at the extremes of age. Corticosteroids were administered to 56 patients and may have contributed to the comparatively good outcome in these cases. 相似文献
113.
N Kates M Craven AM Crustolo L Nikolaou C Allen 《Canadian Metallurgical Quarterly》1997,19(5):324-332
The increasingly prominent role of the family physician in delivering mental health care can be enhanced if productive and collaborative relationships can be established with local mental health services. This paper describes a Canadian program that has achieved this by bringing mental health counselors and psychiatrists into the offices of 87 family physicians in 35 practices in a community in Southern Ontario. The paper describes the program, the activities of counselors and psychiatrists within the practices, and the administrative structures set up to coordinate these activities. Data is presented from the evaluation of the first year of the program's operation (13 practices and 45 family physicians) during which time 3085 referrals were received. The program made mental health care more available and accessible, increased continuity of care, provided additional support for the family physician, offered new opportunities for continuing education, and led to a reduced and more efficient use of other mental health services. The components of the program can be adapted to most communities. 相似文献
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116.
The purpose of this study was to examine the relationship of job satisfaction to job difficulty and worthiness, reported by the clinical psychologists who worked at medical institutions. A mail survey of 748 clinical psychologists working at hospital and clinics revealed the following results. First, job satisfaction was related more to job situation than job content. Also, job satisfaction was low among those who worked at non-university psychiatric or geriatric hospitals, who did not practice psychotherapy, and who were not in education, research, or management. In addition, compared to the high job satisfaction group, the low group perceived more incongruity between institutional climate and their psychological work, felt being less valued by other professionals, were less able to function fully as a practicing psychologist, and experienced more role ambiguity as a clinical psychologist in a hospital setting. 相似文献
117.
G Pillemer R Yelin M Epstein L Gont Y Frumkin JK Yisraeli H Steinbeisser A Fainsod 《Canadian Metallurgical Quarterly》1998,74(1-2):133-143
Patterning of the marginal zone in the Xenopus embryo has been attributed to interactions between dorsal genes expressed in the organizer and ventral-specific genes. In this antagonistic interplay of activities, BMP-4, a gene that is not expressed in the organizer, provides a strong ventralizing signal. The Xenopus caudal type homeobox gene, Xcad-2, which is expressed around the blastopore with a gap over the dorsal lip, was analyzed as part of the ventral signal. Xcad-2 was shown to efficiently repress during early gastrula stages the dorsal genes gsc, Xnot-2, Otx-2, XFKH1 and Xlim-1, while it positively regulates the ventral genes, Xvent-1 and Xvent-2, with Xpo exhibiting a strong positive response to Xcad-2 overexpression. Xcad-2 was also capable of inducing BMP-4 expression in the organizer region. Support for a ventralizing role for Xcad-2 was obtained from co-injection experiments with the dominant negative BMP receptor which was used to block BMP-4 signaling. Under lack-of-BMP-signaling conditions Xcad-2 could still regulate dorsal and ventral gene expression and restore normal development, suggesting that it can act downstream of BMP-4 signaling or independently of it. Xcad-2 could also inhibit secondary axis formation and dorsalization induced by the dominant negative BMP receptor. Xcad-2 was also shown to efficiently reverse the dorsalizing effects of LiCl. These results place Xcad-2 as part of the ventralizing gene program which acts during early gastrula stages and can execute its ventralizing function in the absence of BMP signaling. 相似文献
118.
M Albert C Athanassopoulos LB Auerbach D Bauer R Bolton B Boyd RL Burman I Cohen DO Caldwell BD Dieterle JB Donahue AM Eisner A Fazely FJ Federspiel GT Garvey RM Gunasingha V Highland J Hill R Imlay K Johnston WC Louis A Lu AK Mann J Margulies K McIlhany W Metcalf RA Reeder V Sandberg M Schillaci D Smith I Stancu W Strossman MK Sullivan GJ VanDalen W Vernon YX Wang DH White D Whitehouse D Works Y Xiao S Yellin 《Canadian Metallurgical Quarterly》1995,51(3):R1065-R1069
119.
The level of blood lipids and apolipoproteins in subjects being screened for abdominal aortic aneurysms have been investigated. As part of an ultrasound screening programme in a population of 65- to 75-year-olds, blood samples were collected from 1460 of 1504 subjects with a normal aorta (97.1%) and 69 of 70 patients with an abdominal aortic aneurysm > 29 mm (99%). Samples were also taken from 22 of 27 patients (81%) with an ectatic aorta (26-29 mm). Total cholesterol, HDL-cholesterol, LDL-cholesterol, Apo-AI and Apo-B levels were significantly higher in women than in men (P < 0.01). Levels of HDL-cholesterol and Apo-AI were significantly lower in patients with an abdominal aortic aneurysm than in normal subjects (P < 0.001). The mean(s.d.) body mass index was 25.1(3.9) in women and 25.5(3.2) in men with aneurysms and not significantly greater than that of normal subjects (25.2(3.61) and 25.2(3.38) respectively). 相似文献
120.
GW Boehm GF Sherman GD Rosen AM Galaburda VH Denenberg 《Canadian Metallurgical Quarterly》1996,6(5):696-700
BXSB mice have an approximately 40-60% incidence of neocortical ectopias in layer I of the prefrontal/motor cortex. Prior studies have found major behavioral differences between those with ectopias and their non-ectopic littermates. Some of these findings indicate that the two groups differ with respect to spatial reference and working memory. The purpose of this study was to measure reference and working memory in the same animals to test the hypothesis that the ectopics would have better reference memory but less effective working memory. The Lashley III maze has cul-de-sacs which must be eliminated, and T-choices where the animal has to decide whether to go left or right. Ectopic and non-ectopic mice were equally able to learn the maze and did not differ on cul-entry or T-choice errors. Then the maze was inverted and the animals were retested. Turning the maze upside down did not change the relative status of the blind alleys. Therefore, the reference memory knowledge from the prior week's training could be used to avoid entering the culs. However, inverting the maze caused a left-right mirror image reversal of the T-choices. Therefore, prior reference memory information would interfere with learning the new path through the maze, whereas working memory would enable the mouse to eliminate T-choice errors. Ectopic mice made less cul-entry errors and more T-choice errors than their non-ectopic littermates, as predicted. 相似文献