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1.
A new range of stand magnifiers has been released by the COIL company in the United Kingdom. Examination of these magnifiers reveals that they fail to deliver the rated magnifications labelled prominently on the appliances, as a result of the manufacturer's conformance with the requirements of the German DIN standard and the use of back vertex power (F'v) rather than equivalent dioptric power (Fm) of the magnifier. In this study we provide information on the optometric parameters of these new stand magnifiers that will assist the more accurate specification of improvements in vision expected from their use. 相似文献
2.
A significant number of patients undergoing lumbar spine surgery do not obtain pain relief. Such patients with chronic low
back or lower extremity pain may be difficult to treat. A frequent component of therapy is the use of spinal cord stimulation
to help control pain. With careful patient selection, many patients can achieve reasonable levels of pain relief. We review
recent clinical reports, including prospective and randomized studies, that demonstrate up to three quarters of patients implanted
with a spinal cord stimulator for the treatment of failed back surgery syndrome may benefit from its use. This technology
must not be indiscriminately applied. Careful patient selection and a period of trial stimulation are vital to the successful
use of spinal cord stimulation as treatment for chronic pain. 相似文献
3.
Blood pressure (BP) reactivity in children, the transient elevation of BP after an acute stressor, is a stable characteristic that may predict cardiovascular disease (CVD) and hypertension. The purpose of the present study was to assess the generalizability of BP reactivity across various stressors in young children. BP reactivity was measured in 85 children (ages 3 to 6 years) after each of three different stressors. Systolic BP reactivity level was highest after physical exertion (104 mm Hg), followed by competitive task (95 mm Hg) and cognitive task (93 mm Hg). Resting systolic BP was 90. The 2-week test-retest reliability was higher for physical stress systolic BP reactivity level (r = .66) than for baseline systolic BP (r = .58) and the other two stressors. The reliability of the systolic BP change score was significant only for physical stressor (r = .33). Correlations among the three stressors ranged from .75 to .79 for systolic BP reactivity level and from .37 to .50 for change in systolic BP. Change in systolic BP after physical stress correlated with skin-fold thickness (r = .32). There was evidence of generalizability across stressors. The physical task is the most promising for future study of BP reactivity in young children. 相似文献
4.
Paula Goering R.N. Ph.D. Janet Durbin B.Sc. M.A. Robert Foster B.A. Susan Boyles Hons. B.A. Taras Babiak M.D. F.R.C.P. Bill Lancee Ph.D. 《Community mental health journal》1992,28(3):199-214
One goal of supportive housing is to enlarge and improve the functioning of the social support networks of residents. The networks of a convenience sample of 42 residents were assessed using scales developed by Barrera. The size of the networks (11.5) was no larger than that reported for similar clients living in other types of community settings but the composition differed. Staff and co-residents appear to partially replace rather than add to family and friends. This is of concern because friends are uniquely important determinants of satisfaction. An association between perceived need for support and network size was also found. These findings suggest some positive influences but also raise questions about unintended negative consequences of living in artificially constructed social environments.When this project was undertaken, Dr. Goering, Janet Durbin, Bill Lancee and Taras Babiak were all members of the Social and Community Psychiatry Section, Clarke Institute. Robert Foster was Executive Director of Regeneration House, Inc., where Susan Boyles is Assistant Executive Director. 相似文献
5.
Pheochromocytoma and paraganglioma: comparison of MR imaging with CT and I-131 MIBG scintigraphy 总被引:6,自引:0,他引:6
To ascertain the magnetic resonance (MR) imaging characteristics of pheochromocytomas and paragangliomas and to compare MR with computed tomography (CT) and iodine-131 metaiodobenzylguanidine (I-131 MIBG), 19 patients (18 with pheochromocytomas, one with a paraganglioma) were studied. The 18 patients with pheochromocytomas had had positive findings with I-131 MIBG scintigraphy. Abdominal pheochromocytomas were generally hypointense compared with normal liver on T1-weighted MR images and extremely hyperintense on T2-weighted MR images. MR imaging was preferable to CT in the evaluation of primary pheochromocytomas due to superior tissue characterization, particularly in the patient with hypertension and borderline catecholamine levels. For patients with recurrent or metastatic disease, the data suggest that I-131 MIBG scintigraphy is the examination of choice. 相似文献
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9.
Chaperonin-mediated assembly of wild-type and mutant subunits of human propionyl-CoA carboxylase expressed in Escherichia coli 总被引:1,自引:0,他引:1
We developed a bacterial expression system for the human alpha and beta
cDNAs of propionyl-CoA carboxylase (PCC). These cDNAs (less the putative
mitochondrial matrix targeting presequences) were co-expressed in
Escherichia coli on one plasmid vector with each cDNA having its own
IPTG-inducible promoter. Only negligible amounts of active PCC were
measured despite the presence of both alpha and beta subunits as indicated
by Western blot analysis and the almost complete biotinylation of the alpha
subunit. Co-expression of this plasmid with a second plasmid vector
over-expressing the E. coli chaperonin proteins, groES and groEL, resulted
in a several hundred-fold increase in PCC specific activity, to a level
comparable with that found in crude human liver extracts. PCC was partially
purified on monomeric avidin affinity resin and the presence of both alpha
and beta subunits was demonstrated, thereby confirming the assembly of both
subunits into an active enzyme. Deficiency of either alpha PCC or beta PCC
results in propionic acidemia, an autosomal recessive disorder. We used
this expression system to characterize one missense mutation previously
described in five Japanese alleles, namely C1283T (Thr428lle) in beta PCC.
This mutation, when expressed in E.coli under the same conditions as that
of wild-type PCC, had null activity, despite the presence of assembled
alpha PCC and beta PCC subunits. This bacterial expression system can be
useful for analysis of either alpha PCC or beta PCC mutations. Our findings
indicated that the groES and groEL chaperonin proteins were essential for
folding and assembly of the human PCC heteromeric subunits.
相似文献
10.
Pal L; Leykin L; Schifren JL; Isaacson KB; Chang YC; Nikruil N; Chen Z; Toth TL 《Human reproduction (Oxford, England)》1998,13(7):1837-1840
A case series of eight cycles of in-vitro fertilization (IVF) in five women
diagnosed with malignant disorders is presented. These patients chose to
defer definitive treatment for a chance for preservation of potential
fertility. The response of these patients to ovarian stimulation, and the
outcome, was compared with 17 IVF cycles in 12 age- matched patients with
isolated tubal infertility. An apparent adverse influence of malignant
disease on the quality and behaviour of oocytes was observed. Despite a
comparable total number of oocytes per cycle in the two groups, a
significantly reduced percentage of mature oocytes was retrieved per cycle
from patients with malignant diseases. The oocytes from patients with
malignant disorders were of a poorer quality and exhibited a significantly
impaired fertilization rate compared to the controls. We propose that
neoplastic processes, irrespective of the site or cell of origin, may have
a detrimental impact on the biology of oocytes, an effect akin to that seen
on spermatozoa in men with certain malignancies.
相似文献