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11.
12.
Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
13.
14.
Recent changes in UK law have allowed UK-based optometrists to sell and supply fusidic acid viscous eyedrops, providing it is in the course of their professional activity and in an emergency. Alternatively, the optometrist may access fusidic acid viscous eyedrops, for a named patient, using a written order supplied to a pharmacy. This review provides details of the legal background to these changes, examines the common causes of a bacterial conjunctivitis, examines the mechanism of action of this narrow spectrum antibiotic as a bacteriostatic agent, reviews the susceptibility of common ocular isolates of bacteria to the drug and presents details of the expected pharmacokinetics of the viscous eyedrops. From this perspective, a systematic review is provided of the clinical studies which have investigated the use of fusidic acid viscous eyedrops and their outcome. The indicated use is generally for the treatment of bacterial conjunctivitis and/or blepharoconjunctivitis, especially that caused by Staphylococcus, but not Streptococcus or Haemophilus sp. (more likely associated with concurrent nasopharyngeal infections). The usual regimen for use is twice daily for 5-10 days, depending on severity, and can initially be used more intensively (four times per day). It may also be used for the management of corneal and conjunctival abrasions and foreign body injuries, or some cases of chronic blepharitis. 相似文献
15.
Christine N Vidal Rob Nicolson Timothy J DeVito Kiralee M Hayashi Jennifer A Geaga Dick J Drost Peter C Williamson Nagalingam Rajakumar Yihong Sui Rebecca A Dutton Arthur W Toga Paul M Thompson 《Neuropsychopharmacology》2006,60(3):218-225
BACKGROUND: Volumetric studies have reported reductions in the size of the corpus callosum (CC) in autism, but the callosal regions contributing to this deficit have differed among studies. In this study, a computational method was used to detect and map the spatial pattern of CC abnormalities in male patients with autism. METHODS: Twenty-four boys with autism (aged 10.0 +/- 3.3 years) and 26 control boys (aged 11.0 +/- 2.5 years) underwent a magnetic resonance imaging (MRI) scan at 3 Tesla. Total and regional areas of the CC were determined using traditional morphometric methods. Three-dimensional (3D) surface models of the CC were also created from the MRI scans. Statistical maps were created to visualize morphologic variability of the CC and to localize regions of callosal thinning in autism. RESULTS: Traditional morphometric methods detected a significant reduction in the total callosal area and in the anterior third of the CC in patients with autism; however, 3D maps revealed significant reductions in both the splenium and genu of the CC in patients. CONCLUSIONS: Statistical maps of the CC revealed callosal deficits in autism with greater precision than traditional morphometric methods. These abnormalities suggest aberrant connections between cortical regions, which is consistent with the hypothesis of abnormal cortical connectivity in autism. 相似文献
16.
Linda J. Richards Trevor J. Kilpatrick Renee Dutton Seong-Seng Tan David P. Gearing Perry F. Bartlett Mark Murphy 《The European journal of neuroscience》1996,8(2):291-299
Previously we have shown that leukaemia inhibitory factor (LIF) potentiates the development of murine spinal cord neurons in vitro , suggesting that it, or related factors, may play an important regulatory role in neuronal development. We have further investigated this role and show here that the generation of neurons in cultures of embryonic day 10 spinal cord cells is inhibited by antibodies to the β subunit of the LIF receptor. Since there are more undifferentiated precursors in antibody-treated cultures than in control and LIF-treated cultures, it is concluded that the primary action of LIF, or related molecules, is to promote neuronal differentiation, not precursor survival. In addition, the failure of LIF to support neuronal survival in the period immediately following differentiation suggests that the increased numbers of neurons generated with LIF are not attributable to its neurotrophic action. By selecting neuronal precursors on the basis of their inability to express class I major histocompatibility complex molecules, it was shown that LIF acted directly upon these cells and not via an intermediary cell. LIF also appears to be involved in regulating the differentiation of astrocytes, since it increases the number of glial fibrillary protein (GFAP)-positive cells present in the cultures and since the spontaneous production of GFAP-positive cells is blocked by antibodies to the LIF β receptor. These findings suggest that LIF or related factors promote the differentiation of neural precursors in the spinal cord, but that they are not involved in preferentially promoting precursors down a specific differentiation pathway. 相似文献
17.
BACKGROUND: Growing interest is nowadays focused on the quality of life of
elderly people who survive with chronic diseases. Coronary heart disease
(CHD) is one of the most common diseases among the elderly and may have an
unfavourable impact on the patient's emotional well-being. OBJECTIVES: We
aimed to describe the prevalence of depression and the occurrence of
depressive symptoms among elderly CHD patients, with a special emphasis on
the relations between depression and the severity of CHD, and to find out
the possible association between CHD and depression. METHODS: The study was
carried out at the health centre of the municipality of Lieto, in
south-west Finland. The study population consisted of 488
community-dwelling men and 708 women, over 64 years old, from among whom
the participants with CHD (89 men and 73 women) were selected, and for whom
178 male and 146 female sex- and age- matched controls (free of CHD) were
drawn from the population. CHD patients were selected on the basis of the
presence of angina pectoris or a past myocardial infarction. Depressive
symptoms were measured with the Zung Self-rating Depression Scale.
Depression was described in relation to the severity of dyspnoea and chest
pain among patients. The associations between depression and age, health,
health behaviour, drugs, functional ability and social, psychosocial and
environmental factors were analysed by logistic regression analyses.
RESULTS: The prevalence of depression was 29% among male patients and 20%
among female patients. Depression was significantly more common among male
CHD patients than among male controls (P = 0.011). Among women, depression
was not associated with CHD. Earlier, depression had gone undiagnosed among
many CHD patients and controls, especially male patients. Among male CHD
patients, depression was associated with more severe dyspnoea, but no
similar association was found among female CHD patients. Among men the
occurrence of CHD, physical disability, widowhood or divorce, and among
women previous clinical depression, physical disability and the use of
angiotensin-converting enzyme (ACE) inhibitors, were associated with
depression. CONCLUSION: Depression is common among patients with CHD. It
seems that CHD is not an independent factor in the aetiology of depression
among the elderly. The association of CHD with depression among men is
explained by the acute or chronic psychic stress caused by CHD. It may be
that the more complicated the patient's CHD, the more probable is the
presence of depression.
相似文献
18.
A E O'Hare MD FRCP G N Dutton FRCS FRCOphth D Green MB ChB MRCP Rosemary Coull 《Developmental medicine and child neurology》1998,40(6):417-420
The progress of cognitive visual dysfunction over an 8-year period of a child who sustained bilateral occipital-lobe infarctions at the age of 21/2 years is described. She survived with normal intelligence and went on to attend mainstream school. She manifested many features of cognitive visual impairment and, in particular, developed a form of pure alexia without agraphia. She achieved some letter-by-letter reading but no sight vocabulary development, including to her own name. She learned to write imaginatively employing phonetically true spelling but cannot read what she has written. Her progress and the difficulties encountered during the management of her condition are discussed in this first case report of the evolution of pure alexia without agraphia in childhood. The features of this syndrome in the developing child who has never developed the capacity to read are contrasted with that seen in affected adults. 相似文献
19.
IS Park H Kiyomoto F Alvarez YC Xu HE Abboud SL Abboud 《American journal of kidney diseases》1998,32(6):1000-1010
The renal insulin-like growth factor-I (IGF-I) system has been implicated in the pathogenesis of renal hypertrophy, altered hemodynamics, and extracellular matrix expansion associated with early diabetes. The relative abundance of IGF binding proteins (IGFBPs) in the renal microenvironment may modulate IGF-I actions. However, the precise IGFBPs expressed in the glomerular and tubulointerstitial compartments during diabetic renal growth have not been characterized. In the present study, in situ hybridization studies were performed to examine the expression of IGFBP-1 to -6 messenger RNAs (mRNAs) 3, 7, and 14 days after streptozotocin (STZ) injection in rats. In control, nondiabetic kidneys, all six IGFBP mRNAs were differentially expressed with a predominance of IGFBP-5. The onset of renal hypertrophy in STZ-induced diabetes was associated with a rapid and site-specific induction of IGFBP-1, -3, and -5 mRNAs. In contrast, basal expression of IGFBP-2, -4, and -6 mRNAs was not altered in diabetic rats. IGFBP-5 mRNA expression increased in diabetic glomeruli, cortical, and inner medullary peritubular interstitial cells at days 3, 7, and 14. Although normal glomeruli failed to express IGFBP-3, it was induced concomitantly with IGFBP-5 in diabetic glomeruli and cortical peritubular interstitial cells. IGFBP-1 mRNA levels also increased in cortical tubular cells at each time point tested. Peak induction of IGFBP-3 and -5 was observed at day 3, whereas IGFBP-1 was delayed until day 7. IGFBP-1, -3, and -5 mRNA levels declined by day 14, but remained persistently elevated above control. By immunoperoxidase staining, similar alterations in the pattern of IGFBP-3 and -5 protein expression were observed at each time point. The preferential and site-specific increase in IGFBP-1, -3, and -5 suggest that these IGFBPs may regulate the local autocrine and/or paracrine actions of IGF-I and contribute to the pathogenesis of the early manifestations of diabetic nephropathy. 相似文献
20.
Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group 总被引:5,自引:0,他引:5
Haines JL; Terwedow HA; Burgess K; Pericak-Vance MA; Rimmler JB; Martin ER; Oksenberg JR; Lincoln R; Zhang DY; Banatao DR; Gatto N; Goodkin DE; Hauser SL 《Human molecular genetics》1998,7(8):1229-1234
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the
central nervous system. While its etiology is not well understood, genetic
factors are clearly involved. Until recently, most genetic studies in MS
have been association studies using the case-control design testing
specific candidate genes and studying only sporadic cases. The only
consistently replicated finding has been an association with the HLA-DR2
allele within the major histocompatibility complex (MHC) on chromosome 6.
Using the genetic linkage design, however, evidence for and against linkage
of the MHC to MS has been found, fostering suggestions that sporadic and
familial MS have different etiologies. Most recently, two of four genomic
screens demonstrated linkage to the MHC, although specific allelic
associations were not tested. Here, a dataset of 98 multiplex families was
studied to test for an association to the HLA-DR2 allele in familial MS and
to determine if genetic linkage to the MHC was due solely to such an
association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta)
in the MHC demonstrated strong genetic linkage (parametric lod scores of
4.60, 2.20 and 1.24, respectively) and a specific association with the
HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results
by HLA-DR2 status showed that the linkage results were limited to families
segregating HLA-DR2 alleles. These results demonstrate that genetic linkage
to the MHC can be explained by the HLA-DR2 allelic association. They also
indicate that sporadic and familial MS share a common genetic
susceptibility. In addition, preliminary calculations suggest that the MHC
explains between 17 and 62% of the genetic etiology of MS. This
heterogeneity is also supported by the minority of families showing no
linkage or association with loci within the MHC.
相似文献