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991.
Salmon calcitonin nasal spray in the prevention of corticosteroid- induced osteoporosis 总被引:5,自引:0,他引:5
Adachi JD; Bensen WG; Bell MJ; Bianchi FA; Cividino AA; Craig GL; Sturtridge WC; Sebaldt RJ; Steele M; Gordon M; Themeles E; Tugwell P; Roberts R; Gent M 《Rheumatology (Oxford, England)》1997,36(2):255-259
The objectives were to determine the efficacy and safety of nasal salmon
calcitonin 200 IU daily in the prevention of corticosteroid- induced
osteoporosis. A minimized, double-blind, placebo-controlled trial was
carried out in corticosteroid-treated patients with polymyalgia rheumatica.
The setting was a tertiary care university- affiliated hospital and a total
of 31 patients were enrolled. The primary outcome measure was the
percentage change in bone mineral density of the lumbar spine in the two
treatment groups from baseline to 1 yr of follow-up. The mean +/- S.D. bone
mineral density of the lumbar spine in the calcitonin-treated group
decreased by 1.29 +/- 6.76% and in the placebo group by 4.95 +/- 3.50%
after 12 months. The observed difference of 3.65 +/- 2.10% between groups
is statistically significant (P < 0.05). Nasal salmon calcitonin
prevented loss of bone in the lumbar spine as measured by dual-energy X-ray
absorptiometry.
相似文献
992.
Achour A Mankaï A Thabet Y Sakly W Braham F Kechrid C Bahri F Bouajina E Chouchène S Haddad O Ghedira I 《Rheumatology international》2012,32(5):1225-1229
Onset of the disease above the age of 65?years is unusual. This study was undertaken to determine retrospectively the clinical and laboratory features in SLE patients aged over 65?years. It is a retrospective study about 18 elderly patients with SLE out of 342 diagnosed between 1994 and 2009 in the center of Tunisia. All patients had at least 4 of 11 revised ACR criteria of SLE. The frequency of SLE in the elderly was 5.3%. The median age was 70?years (range 66 and 78?years). The sex ratio F/M was 5. The most frequent clinical signs were anemia (83.3%), arthralgia (55.5%), arthritis (38.9%), and malar rash (33.3%). The proteinuria and the neuropsychiatric troubles were present in 27.8% of cases. The pericarditis was present in 16.7% of cases. Antibodies to double stranded DNA (anti-dsDNA) were detected in 66.7%, anti-nucleosome in 50%, anti-SSA and anti-RNP in 27.8%, anti-Sm in 22%, and anti-SSB in 11%. Elderly patients with SLE exhibit distinct clinical and biological manifestations from the classic form. Thus, greater attention should be given for this particular subgroup of SLE patients to avoid delays in diagnosis or misdiagnosis. 相似文献
993.
Overexpression of cyclin D1 in the Dami megakaryocytic cell line causes growth arrest 总被引:4,自引:2,他引:4
The maturation of megakaryocytes in vivo requires polyploidization or repeated duplication of DNA without cytokinesis. As DNA replication and cytokinesis are tightly regulated in somatic cells by cyclins and cyclin-dependent kinases, we sought to determine the pattern of cyclin gene expression in cells that undergo megakaryocytic differentiation and polyploidization. The Dami megakaryocytic cell line differentiates and increases ploidy in response to phorbol 12-myristate 13-acetate (PMA) stimulation in vitro. We used Northern blotting to analyze mRNA levels of cyclins A, B, C, D1, and E in PMA-induced Dami cells and found that cyclin D1 mRNA levels increased dramatically (18-fold). Similar increases in cyclin D1 mRNA were obtained for other cell lines (HEL and K562) with megakaryocytic properties, but not in HeLa cells. The increase in cyclin D1 was confirmed by Western immunoblotting of PMA-treated Dami cells. This finding suggested that cyclin D1 might participate in megakaryocyte differentiation by promoting endomitosis and/or inhibiting cell division. To address these possibilities, we constructed two stable Zn+2-inducible, cyclin D1-overexpressing Dami cell lines. Cyclin D1 expression alone was not sufficient to induce polyploidy, but in conjunction with PMA-induced differentiation, polyploidization was slightly enhanced. However, unlike other cell systems, cyclin D1 overexpression caused cessation of cell growth. Although the mechanism by which cyclin D1 may affect megakaryocyte differentiation is not clear, these data demonstrate that cyclin D1 is upregulated in differentiating megakaryocytic cells and may contribute to differentiation by arresting cell proliferation. 相似文献
994.
Objectives
The aim of the study was to determine the relationship between alcohol consumption and liver fibrosis as assessed by aspartate aminotransferase to platelet ratio index (APRI) in HIV‐infected adults and to explore the relative contributions of alcohol and hepatitis C virus (HCV) to APRI among HIV/HCV‐coinfected adults.Methods
We performed a cross‐sectional analysis of data from an observational clinical cohort. Alcohol consumption was categorized according to National Institute on Alcohol Abuse and Alcoholism guidelines. We defined significant liver disease as APRI>1.5, and used multinomial logistic regression to identify correlates of increased APRI.Results
Among 1358 participants, 10.4% reported hazardous drinking. It was found that 11.6% had APRI>1.5, indicating liver fibrosis. Hazardous drinking was associated with increased APRI [adjusted relative risk ratio (RRR) 2.30; 95% confidence interval (CI) 1.26–4.17]. Other factors associated with increased APRI were male gender, viral hepatitis, and HIV transmission category of injecting drug use. Among coinfected individuals, 18.3% had APRI>1.5, and hazardous drinking was not associated with APRI. Among non‐HCV‐infected individuals, 5.3% had APRI>1.5 and hazardous drinking was associated with increased APRI (adjusted RRR 3.72; 95% CI 1.40–9.87).Conclusions
Hazardous drinking is an important modifiable risk factor for liver fibrosis, particularly among non‐HCV‐infected patients. Clinicians and researchers must address alcohol use as the burden of liver disease increases among HIV‐positive individuals. 相似文献995.
996.
Association of HLA-DR with susceptibility to and clinical expression of rheumatoid arthritis: re-evaluation by means of genomic tissue typing 总被引:1,自引:2,他引:1
Van Jaarsveld CH; Otten HG; Jacobs JW; Kruize AA; Brus HL; Bijlsma JW 《Rheumatology (Oxford, England)》1998,37(4):411-416
The clinical expression of rheumatoid arthritis (RA) varies considerably
among individual patients. Genetic variations in human leucocyte antigen
(HLA) may influence clinical expression. We re- examined the association of
HLA-DR with susceptibility to and clinical expression of RA using genomic
tissue typing, since most studies were based on (less reliable) serological
techniques. Seventy-eight patients with recent-onset RA, all participating
in a clinical trial on therapeutic strategies, were HLA-DR typed by means
of low-resolution genomic typing. Cumulative disease activity within the
first 3 yr of disease was measured. Of the RA patients, 54% expressed DR4
(DR4+) vs 26% of healthy controls. Rheumatoid factor (RF)-positive patients
had a higher cumulative disease activity than RF-negative patients.
Patients who were either DR1+ or DR4+ had a higher cumulative disease
activity than those who expressed neither DR1 nor DR4. This association was
less obvious after correction for RF status. The association of DR52+ (DR3,
5, 6) and a lower cumulative disease activity could also not be
demonstrated after correction for RF status. Among RF-negative patients,
DR51+ (or DR2+) was associated with a higher cumulative disease activity.
Other HLA-DR types (including DR1 and DR4 separately) were not associated
with the severity of RA. DR4 was associated with susceptibility to RA in
our patients; HLA-DR low-resolution genomic tissue typing did not yield
additional information to RF status for the clinical identification of
individual patients with a poor prognosis.
相似文献
997.
998.
Objective
To compare image quality and radiation dose of abdominal CT examinations reconstructed with three image reconstruction techniques.Methods
In this Institutional Review Board-approved study, contrast-enhanced (CE) abdominopelvic CT scans from 23 patients were reconstructed using filtered back projection (FBP), adaptive statistical iterative reconstruction (ASiR) and iterative reconstruction in image space (IRIS) and were reviewed by two blinded readers. Subjective (acceptability, sharpness, noise and artefacts) and objective (noise) measures of image quality were recorded for each image data set. Radiation doses in CT dose index (CTDI) dose–length product were also calculated for each examination type and compared. Imaging parameters were compared using the Wilcoxon signed rank test and a paired t-test.Results
All 69 CECT examinations were of diagnostic quality and similar for overall acceptability (mean grade for ASiR, 3.9±0.3; p=0.2 for Readers 1 and 2; IRIS, 3.9±0.4, p=0.2; FBP, 3.8±0.9). Objective noise was considerably lower with both iterative techniques (p<0.0001 and 0.0016 for ASiR and IRIS). Recorded mean radiation dose, i.e. CTDIvol, was 24% and 10% less with ASiR (11.4±3.4 mGy; p<0.001) and IRIS (13.5±3.7 mGy; p=0.06), respectively, than with FBP: 15.0±3.5 mGy.Conclusion
At the system parameters used in this study, abdominal CT scans reconstructed with ASiR and IRIS provide diagnostic images with reduced image noise and 10–24% lower radiation dose than FBP.Advances in knowledge
CT images reconstructed with FBP are frequently noisy on lowering the radiation dose. Newer iterative reconstruction techniques have different approaches to produce images with less noise; ASiR and IRIS provide diagnostic abdominal CT images with reduced image noise and radiation dose compared with FBP. This has been documented in this study.CT continues to expand its role as an essential imaging modality [1]. However, with its increasing use, concerns of radiation overexposure have prompted efforts to reduce the cumulative dose to a patient [2]. Recent studies have highlighted increased utilisation of radiological examination and 10-fold increase in medical radiation exposure at the population level [3,4]. Therefore, lowering the CT radiation dose without compromising the image quality is desirable. Several technical approaches have been proposed to accomplish these goals including commonly used tube current modulation and adopting lower peak kilovoltage [5-8]. However, excessive dose reduction has remained difficult in the abdomen and pelvis CT due to increased levels of image noise and artefacts that lower the quality of the CT examination. Moreover, abdominopelvic CT demands higher image quality for confident detection of low-contrast lesions in various viscera [9]. The conventional technique of image reconstruction, filtered back projection (FBP), is an efficient method for image production, but makes several assumptions and therefore requires higher dose for delivering diagnostic quality images [10,11]. To overcome these limitations, iterative reconstruction (IR) techniques have been introduced, which have been shown to render optimal image quality at lower radiation dose [12-20]. Unlike advanced iterative techniques, partial IR approaches such as adaptive statistical iterative reconstruction (ASiR) and iterative reconstruction in image space (IRIS) are computationally less demanding and therefore faster to process images. In essence, both rely on mathematic modelling of the CT raw data to selectively identify image noise and reduce it. The ASiR technique models statistical variations in the distribution of noise from acquired image data and improves the signal-to-noise ratio while preserving image contrast [5,8,12]. Since its introduction, several investigators have confirmed its capabilities to deliver diagnostic quality images at 30–50% lower radiation dose. [8,12]. IRIS, on the other hand, reduces image noise by forming multiple iterations within the image space itself [10-14]. Phantom studies have demonstrated its ability in maintaining transverse and z-axis spatial resolution, as well as CT number accuracy and linearity while reducing image noise [18]. Its capability in preserving diagnostic accuracy and improving image quality at lower tube potential settings has been documented by Schindera et al [18] as has its ability to reduce noise and radiation dose in clinical studies by approximately 35–50% [11-16]. Owing to differences in image reconstruction approach by ASiR and IRIS, we investigated the performance of these two IR methods on image quality and radiation dose in patients undergoing contrast-enhanced (CE) abdominal CT examinations compared with the FBP technique. 相似文献999.
1000.
Urachal remnants: sonographic demonstration in children 总被引:1,自引:0,他引:1
On 62 of 100 pediatric bladder sonograms a small, elliptical, hypoechoic structure was observed on the middle of the anterosuperior surface of the urinary bladder. One of the these structures was removed surgically, and pathologic examination disclosed a normal urachal remnant. Since it is a common sonographic finding in children, it should not be mistaken for a pathologic process unless it is accompanied by signs and symptoms of infection or bladder obstruction. 相似文献