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991.
Cognitive and behavioral outcomes of school-aged children who were born preterm: a meta-analysis 总被引:29,自引:1,他引:28
Context The cognitive and behavioral outcomes of school-aged children who were born preterm have been reported extensively. Many of these studies have methodological flaws that preclude an accurate estimate of the long-term outcomes of prematurity. Objective To estimate the effect of preterm birth on cognition and behavior in school-aged children. Data Sources MEDLINE search (1980 to November 2001) for English-language articles, supplemented by a manual search of personal files maintained by 2 of the authors. Study Selection We included case-control studies reporting cognitive and/or behavioral data of children who were born preterm and who were evaluated after their fifth birthday if the attrition rate was less than 30%. From the 227 reviewed studies, cognitive data from 15 studies and behavioral data from 16 studies were selected. Data Extraction Data on population demographics, study characteristics, and cognitive and behavioral outcomes were extracted from each study, entered in a customized database, and reviewed twice to minimize error. Differences between the mean cognitive scores of cases and controls were pooled. Homogeneity across studies was formally tested using a general variance-based method and graphically using Galbraith plots. Linear meta-analysis regression models were fitted to explore the impact of birth weight and gestational age on cognitive outcomes. Study-specific relative risks (RRs) were calculated for the incidence of attention-deficit/hyperactivity disorder (ADHD) and pooled. Quality assessment of the studies was performed based on a 10-point scale. Publication bias was examined using Begg modified funnel plots and formally tested using the Egger weighted-linear regression method. Data Synthesis Among 1556 cases and 1720 controls, controls had significantly higher cognitive scores compared with children who were born preterm (weighted mean difference, 10.9; 95% confidence interval [CI], 9.2-12.5). The mean cognitive scores of preterm-born cases and term-born controls were directly proportional to their birth weight (R2 = 0.51; P<.001) and gestational age (R2 = 0.49; P<.001). Age at evaluation had no significant correlation with mean difference in cognitive scores (R2 = 0.12; P = .20). Preterm-born children showed increases in externalizing and internalizing behaviors in 81% of studies and had more than twice the RR for developing ADHD (pooled RR, 2.64; 95% CI, 1.85-3.78). No differences were noted in cognition and behaviors based on the quality of the study. Conclusions Children who were born preterm are at risk for reduced cognitive test scores and their immaturity at birth is directly proportional to the mean cognitive scores at school age. Preterm-born children also show an increased incidence of ADHD and other behaviors. 相似文献
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Kiziltepe U Eyileten ZB Uysalel A Akalin H 《International journal of cardiology》2002,85(2-3):297-299
Prolonged pleural effusions following a Fontan operation are a difficult problem. Although fenestrations and embolizations of systemic-pulmonary artery collaterals were suggested to treat and to decrease the risk of this complication, talc slurry pleurodesis may successfully augment and accelerate the beneficial effects of those techniques against the resistant effusions. 相似文献
996.
c-myc proto-oncogene expression in hemophilic synovitis: in vitro studies of the effects of iron and ceramide 总被引:5,自引:2,他引:3
Hemophilia is a rare congenital bleeding disorder that is due to the deficiency of blood coagulation factor VIII or IX. Recurrent musculoskeletal bleeding is common and bleeding into joints results in a chronic inflammatory condition termed hemophilic synovitis. This destructive process is characterized by hemosiderin deposition in the superficial and deeper layers of the synovial membrane as well as a proliferation of synovial fibroblasts and vascular cells. The hyperplastic synovium and neovascular changes are reminiscent of the histopathologic appearance observed in malignant tissues. Indeed, the benign hyperplastic synovium in patients with hemophilia displays similar invasive and destructive behaviors suggesting the possibility of analogous disturbances in growth control and locally invasive mechanisms. Iron plays a role in malignant cell growth, local invasion, and tumor progression, possibly due to changes in the expression of the proto-oncogene, c-myc. We hypothesized that iron plays a similar role in hemophilic synovitis. To explore this hypothesis, we investigated the in vitro effects of iron on the proliferation of a primary, human synovial fibroblast cell (HSFC) line and the involvement of c-myc in this process. We also examined the role of ceramide, a sphingolipid capable of inducing apoptosis in this model system. HSFC proliferation was increased in a dose-dependent fashion and c-myc expression was enhanced by ferric citrate compared to sodium citrate control. Ceramide prevented both the iron-induced increases in HSFC proliferation and c-myc expression. These results indicate that iron probably plays a role in the proliferative changes observed in hemophilic joint disease and that aberrant expression of c-myc may underlie the iron effects. Furthermore, these results suggest that there may be a therapeutic role for ceramide in reversing these changes. 相似文献
997.
Abu-Surrah AS Al-Allaf TA Rashan LJ Klinga M Leskelä M 《European journal of medicinal chemistry》2002,37(11):919-922
The palladium(II) complex trans-bis[(R)-(+)-bornylamino]palladium(II) dichloride was synthesised and characterised. The solid state structure of the complex was determined by X-ray structure analysis. The compound crystallises in the monoclinic space group P2(1) with a=12.383(2), b=23.689(5), c=12.769(3) A, beta=93.25(3) degrees, and V=3739.6(13) A(3). The complex was tested for its cytotoxicity against L(929), K(562) and HeLa cell lines using the MTT assay technique. It is also tested for its anticomplementary activity using a test that detects complement proteins inhibition. These activities were compared with those of the reference standards, cisplatin, carboplatin and oxaliplatin. The significance of these results is given and discussed. 相似文献
998.
Adnan A Ezzat Ezzeldin M Ibrahim Madras A Raja Saif Al-Sobhi Assem Rostom Robert K Stuart 《Medical oncology (Northwood, London, England)》1999,16(2):95-103
In the Kingdom of Saudi Arabia (KSA), breast cancer constitutes 18% of all cancers in Saudi women. Whilst locally advanced
breast cancer disease is unusual in Western countries, it constitutes more than 40% of all non-metastatic breast cancer in
KSA. The relative frequency of locally advanced disease among our breast cancer population and the lack of a uniform consensus
in the literature about its optimal management have prompted this retrospective analysis of the medical records of patients
with Stage III breast cancer patients seen at King Faisal Specialist Hospital and Research Center between 1981 and 1991. In
all, 315 patients were identified. Their median age ±SD was 46±11.6 years which is distinctly different from the 60–65 years
median age in industrial Western nations. Most patients were younger than 50 years (64%) and premenopausal (62%). Patients
were approximately equally divided between Stage III A and Stage III B Patients received multimodality treatment, including
surgery., adjuvant chemotherapy, tamoxifen, and adjuvant radiotherapy. Sixty-one patients were excluded from survival analysis
as they were considered lost to follow-up. Of the remaining 254 patients, 73 (29%) were alive and disease free, and 18 patients
(7%) were alive but, with evidence of the disease. The remaining 163 (64%) had died from breast cancer or its related complications.
Their median overall survival (OS) was 54 months, (95%, Cl, 27 to 121 months) and the median progression-free survival (PFS)
was 28.8 months (95% Cl, 14.2 to 113 months). Cox proportional hazard, model identified Stage III B and the number of positive
axillary lymph nodes as poor predictors of OS and PFS. Radiotherapy was the only adjuvant modality that affected survival
favourably. The prognosis of patients with Stage III disease remains poor despite the use of a multimodality approach. The
overall young age of our patients may have contributed to the poor outcome. Moreover, the adverse effect of Stage III B disease
(as compared with Stage III A) and axillary nodal status was evident. Whilst the favourable effect of radiotherapy on survival
was demonstrated, the lack of independent efficacy of other modalities (adjuvant chemotherapy and tamoxifen) or the apparent
deleterious effect of neoadjuvant chemotherapy should be addressed with discretion in such retrospective analysis. Optimal
management of patients with locally advanced breast cancer disease should be appraised in well designed, prospective, randomised
studies. 相似文献
999.
MJ Cherian Mohamed H Dahniya Najib F Al-Marzouk Adnan Abel Sanaa Bader Khaleda Buerki Othman Z Mahdi 《Journal of Medical Imaging and Radiation Oncology》1998,42(4):303-308
In a review of the chest X-rays and medical records of 597 cases of culture- or biopsy-proven pulmonary tuberculosis (PTB; age range 1.5-72 years), seen over a period of 6 years (1991-97), 26 patients had radiographic patterns unusual for PTB. These patterns were mass-like densities simulating neoplasms, chronic lower lobe airspace opacities without adenopathy, mediastinal adenopathy without parenchymal airspace opacities and bronchopleural fistula without other radiographic abnormalities. The most common of these unusual radiographic patterns was mass-like densities, most of which were initially and mistakenly diagnosed as neoplasms. These masses, seen in 11 adult patients, form the basis of this report. Two children aged 1.5 and 2 years also had tuberculous mass densities initially diagnosed as neurogenic tumour and round pneumonia, respectively. They have been excluded from the present series, and form the subject of another report. The masses were lower lobe predominant and were not usually associated with fibro-productive satellite lesions or with calcification or cavitation. In view of the recent resurgence of PTB and the importance of chest X-rays in its diagnosis and management, this rare radiographic pattern needs to be emphasized. 相似文献
1000.
Simpson A Soderstrom L Ahlstedt S Murray CS Woodcock A Custovic A 《The Journal of allergy and clinical immunology》2005,116(4):744-749
BACKGROUND: IgE-mediated sensitization is usually considered a dichotomous variable (either sensitized or not). Quantitative IgE antibody analysis may better predict the expression of wheeze. OBJECTIVE: Within the context of a population-based birth cohort, we investigated the association among wheeze, lung function, and specific IgE antibody levels. METHODS: Children (n = 521) were followed to age 5 years with repeated questionnaires, skin testing, and measurement of lung function (specific airway resistance) and specific serum IgE (ImmunoCAP). RESULTS: Using specific IgE as a continuous variable, the risk of current wheeze increased significantly with increasing IgE to mite, cat, and dog (P < .0001). When IgE levels to these 3 allergens were summed, the probability of current wheeze increased 1.33-fold (95% CI, 1.21-1.47; P < .0001) per logarithmic unit increase, corresponding to an odds ratio of 3.1 at 10 and 4.25 at 30 kU(A)/L (kilo units of Allergen per liter). Similarly, increasing sum of mite-specific, cat-specific, and dog-specific IgE was associated with reduced lung function (P = .004). Among sensitized children (n = 184), the sum of mite, cat, and dog IgE was the strongest associate of current wheeze (odds ratio, 1.28; 95% CI, 1.13-1.46; P < .001), corresponding to an odds ratio of 2.56 at 10 and 3.32 at 30 kU(A)/L. There was no association between current wheeze and the size of skin test wheal. Furthermore, the sum of IgE to mite, cat, and dog at age 3 years increased the risk of persistent wheeze by age 5 years (2.15-fold/logarithmic unit increase in the specific IgE). CONCLUSION: IgE-mediated sensitization is not an all or nothing phenomenon. The probability of wheeze and reduced lung function increases with increasing specific IgE antibody levels. 相似文献