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排序方式: 共有468条查询结果,搜索用时 31 毫秒
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Henrietta S. Bada Sheldon B. Korones Garland D. Anderson Hubert L. Magill Seok P. Wong 《American journal of obstetrics and gynecology》1984,148(6):798-804
One hundred fifty-five inborn infants with a birth weight <- 1,500 gm were prospectively evaluated for germinal layer/intraventricular hemorrhage. Maternal characteristics, obstetric factors, and neonatal condition in the immediate newborn period were analyzed as possible risk factors for germinal layer/intraventricular hemorrhage. Early germinal layer/intraventricular hemorrhage or hemorrhages identified during the first 24 hours of life were observed in 85 (55%) of these infants. Another 37 (24%) had germinal layer/intraventricular hemorrhage after 24 hours of age (late germinal layer/intraventricular hemorrhage). None of the maternal and obstetric variables, including labor, mode of delivery, and presentation, appeared to increase the risk of germinal layer/intraventricular hemorrhage. The immediate neonatal condition, birth weight, gestational age, and intrauterine growth, all influenced the occurrence of germinal layer/intraventricular hemorrhage, especially early germinal layer/intraventricular hemorrhage. We suggest that future studies to investigate the role of maternal or obstetric factors in the pathogenesis of germinal layer/intraventricular hemorrhage should discriminate early from late germinal layer/intraventricular hemorrhage. Obstetric factors are more likely to influence the early onset of germinal layer/intraventricular hemorrhage; their effect, if any, becomes less discernible later. 相似文献
23.
Regulation of the human telomerase reverse transcriptase gene 总被引:34,自引:0,他引:34
24.
The effects of chronic exposure to excitatory amino acids (EAAs) were examined in cultured cerebellar granule cells (CGCs) from wild type (WT) and interleukin-1 receptor type I (IL-1RI)-deficient mice. After 8 days in culture, the cells were exposed to 100 microM glutamate or 300 microM N-methyl-D-aspartate (NMDA) for 24 h. Analysis of cell viability, as assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay and phase-contrast microscopy revealed that CGCs from IL-1RI-deficient mice were more vulnerable to EAAs as compared to the WT controls. The results indicate that IL-1RI signalling is important for neuronal survival. The effect of glutamate on the CGCs from IL-1RI-deficient mice was decreased by the non-competitive NMDA-receptor antagonist MK-801, supporting the involvement of NMDA receptors in the glutamate-induced excitotoxicity. 相似文献
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Giulio J. D'Angio Henrietta Rosenberg Katrina Sharples Panos Kelalis Norman Breslow Daniel M. Green 《Pediatric blood & cancer》1993,21(3):205-212
The patterns of disease distribution at diagnosis and during follow-up were cataloged for the primary renal tumors of childhood. These data, derived from more than 1,500 patients, were used to define the most rewarding and cost-effective imaging methods required for patient management. The basic information needed prior to surgery includes whether there is a functioning kidney on the opposite side, and whether there are lung metastases or inferior vena cava thrombi. Simple X-ray examinations and ultrasonography (US) will provide the necessary data. Postoperatively, when the histology is known, examination of the brain (MRI or CT scan) is needed for patients with the rhabdoid tumor and clear cell sarcoma of the kidney (CCSK) who are prone to develop brain lesions; and the skeletal system (bone scan, X-ray skeletal survey) for CCSK and for renal cell carcinoma patients who tend to develop bone metastases. Continuing examination of the lung (chest films) is required for all histologies except perhaps for mesoblastic nephroma, which seldom metastasizes. The opposite kidney needs follow-up (US) for 5 or more years to exclude metachronous involvement if nephrogenic rests are present in either kidney. Sophisticated imaging studies, which cost five times or more than simple X-ray examinations or US, are not warranted routinely, and should be reserved for those cases where simpler, less expensive studies do not suffice for reaching patient management decisions. © 1993 Wiley-Liss, Inc. 相似文献
27.
Current global iodine status and progress over the last decade towards the elimination of iodine deficiency 总被引:6,自引:0,他引:6
Andersson M Takkouche B Egli I Allen HE de Benoist B 《Bulletin of the World Health Organization》2005,83(7):518-525
OBJECTIVE: To estimate worldwide iodine nutrition and monitor country progress towards sustained elimination of iodine deficiency disorders. METHODS: Cross-sectional data on urinary iodine (UI) and total goitre prevalence (TGP) in school-age children from 1993-2003 compiled in the WHO Global Database on Iodine Deficiency were analysed. The median UI was used to classify countries according to the public health significance of their iodine nutrition status. Estimates of the global and regional populations with insufficient iodine intake were based on the proportion of each country's population with UI below 100 microg/l. TGP was computed for trend analysis over 10 years. FINDINGS: UI data were available for 92.1% of the world's school-age children. Iodine deficiency is still a public health problem in 54 countries. A total of 36.5% (285 million) school-age children were estimated to have an insufficient iodine intake, ranging from 10.1% in the WHO Region of the Americas to 59.9% in the European Region. Extrapolating this prevalence to the general population generated an estimate of nearly two billion individuals with insufficient iodine intake. Iodine intake was more than adequate, or excessive, in 29 countries. Global TGP in the general population was 15.8%. CONCLUSION: Forty-three countries have reached optimal iodine nutrition. Strengthened UI monitoring is required to ensure that salt iodization is having the desired impact, to identify at-risk populations and to ensure sustainable prevention and control of iodine deficiency. Efforts to eliminate iodine deficiency should be maintained and expanded. 相似文献
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Bauer CR Langer JC Shankaran S Bada HS Lester B Wright LL Krause-Steinrauf H Smeriglio VL Finnegan LP Maza PL Verter J 《Archives of pediatrics & adolescent medicine》2005,159(9):824-834
OBJECTIVE: To identify associations between cocaine exposure during pregnancy and medical conditions in newborn infants from birth through hospital discharge. DESIGN: Multisite, prospective, randomized study. SETTING: Brown University, University of Miami, University of Tennessee (Memphis), and Wayne State University.Subjects A total of 717 cocaine-exposed infants and 7442 nonexposed infants. MAIN OUTCOME MEASURES: Results of physical examination and conditions observed during hospitalization. RESULTS: Cocaine-exposed infants were about 1.2 weeks younger, weighed 536 g less, measured 2.6 cm shorter, and had head circumference 1.5 cm smaller than nonexposed infants (all P<.001). Results did not confirm previously reported abnormalities. Central and autonomic nervous system symptoms were more frequent in the exposed group: jittery/tremors (adjusted odds ratio, 2.17; 99% confidence interval, 1.44-3.29), high-pitched cry (2.44; 1.06-5.66), irritability (1.81; 1.18-2.80), excessive suck (3.58; 1.63-7.88), hyperalertness (7.78; 1.72-35.06), and autonomic instability (2.64; 1.17-5.95). No differences were detected in organ systems by ultrasound examination. Exposed infants had more infections (3.09; 1.76-5.45), including hepatitis (13.46; 7.46-24.29), syphilis (8.84; 3.74-20.88), and human immunodeficiency virus exposure (12.37; 2.20-69.51); were less often breastfed (0.26; 0.15-0.44); had more child protective services referrals (48.92; 28.77-83.20); and were more often not living with their biological mother (18.70; 10.53-33.20). CONCLUSIONS: Central and autonomic nervous system symptoms were more frequent in the exposed cohort and persisted in an adjusted analysis. They were usually transient and may be a true cocaine effect. Abnormal anatomic outcomes previously reported were not confirmed. Increased infections, particularly sexually transmitted diseases, pose a serious public health challenge. Exposure increased involvement of child protective services and out-of-home placement. 相似文献
30.
Increase in TNF-alpha and inducible nitric oxide synthase-expressing dendritic cells in psoriasis and reduction with efalizumab (anti-CD11a) 下载免费PDF全文
Lowes MA Chamian F Abello MV Fuentes-Duculan J Lin SL Nussbaum R Novitskaya I Carbonaro H Cardinale I Kikuchi T Gilleaudeau P Sullivan-Whalen M Wittkowski KM Papp K Garovoy M Dummer W Steinman RM Krueger JG 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(52):19057-19062
We find that CD11c(+) cells with many markers of dendritic cells (DCs) are a major cell type in the skin lesions of psoriasis. These CD11c(+) cells, which are evident in both epidermis and dermis, are the sites for the expression of two mediators of inflammation, inducible nitric oxide synthase (iNOS) and TNF-alpha in diseased skin. These cells express HLA-DR, CD40, and CD86, lack the Langerin and CD14 markers of Langerhans cells and monocytes, respectively, and to a significant extent express the DC maturation markers DC-LAMP and CD83. Treatment of psoriasis with efalizumab (anti-CD11a, Raptiva) strongly reduces infiltration by these DCs in patients responding to this agent. Disease activity after therapy was more related to DC infiltrates and iNOS mRNA levels than T cell infiltrates, and CD11c(+) cells responded more quickly to therapy than epidermal keratinocytes. Our results suggest that a type of DC, which resembles murine "Tip-DCs" that can accumulate during infection, has proinflammatory effects in psoriasis through nitric oxide and TNF-alpha production, and can be an important target for suppressive therapies. 相似文献