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101.
Trends in severe bronchopulmonary dysplasia rates between 1994 and 2002   总被引:6,自引:0,他引:6  
OBJECTIVE: To examine temporal trends in the rates of severe bronchopulmonary dysplasia (BPD) between 1994 and 2002. STUDY DESIGN: In a retrospective cohort study, all infants with a gestational age (GA) <33 weeks in a large managed care organization were identified. Annual rates of BPD (defined as an oxygen requirement at 36 weeks corrected GA), severe BPD (defined as respiratory support at 36 weeks corrected GA), and death before 36 weeks corrected GA were examined. RESULTS: Of the 5115 infants in the study cohort, 603 (12%) had BPD, including 246 (4.9%) who had severe BPD. There were 481 (9.5%) deaths before 36 weeks corrected GA. Although the decline in BPD in this period was not significant, the rates of severe BPD declined from 9.7% in 1994 to 3.7% in 2002. Controlling for gestational age, the odds ratio (95% CI) for annual rate of decline in severe BPD was 0.890 (0.841-0.941). Controlling for gestational age, deaths before 36 weeks corrected GA also declined, with the odds ratio (CI) for the annual decline being 0.944 (0.896-0.996). CONCLUSIONS: In this study population, the odds of having of BPD remained constant after controlling for GA. However, the odds of having severe BPD declined on average 11% per year between 1994 and 2002.  相似文献   
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Psychomotor performance is decreased in the aged. This study investigated the relationship between brain oxidative stress, interleukin-6 (IL-6) production by brain tissue ex vivo and psychomotor deficits during aging, and the effects of feeding an antioxidant-rich diet on ex vivo brain IL-6 production and motor function in aged mice. Male BALBc mice reared in SPF conditions and ranging in age from 3 to 24 months were studied. There was a precipitous decline in motor function after 12 months of age and an increase in brain lipid peroxidation and IL-6 production by coronal brain slices ex vivo. In another study, 12-month-old mice were fed diets formulated to provide a disparate range of antioxidants. At 18 months of age psychomotor coordination, motor learning, and ex vivo brain IL-6 production were evaluated. Mice fed an antioxidant-rich diet had improved psychomotor coordination compared to mice fed diet adequate or low in antioxidants. When mice were tested on successive days, only those fed adequate and high antioxidants exhibited motor learning. Analysis of IL-6 production by coronal brain slices indicated that as dietary antioxidants increased, IL-6 production decreased. Collectively, these data indicate that antioxidants improve psychomotor performance in aged mice, and suggest antioxidants may be useful for reducing brain IL-6 production, which has been shown to increase in aged mice.  相似文献   
104.
Ductoscopy-assisted microdochectomy   总被引:2,自引:0,他引:2  
Until 10 years ago, examination of the ductal system of the breast required excision of all the major ducts, in a block of tissue. With mammary ductoscopy, direct visualization of the ducts in vivo has been possible. In the present series of 40 cases, ductoscopy was used to guide the infusion of methylene blue dye, through the endoscope, to find the index duct, which is then removed through a small incision just inside the areola.  相似文献   
105.
OBJECTIVE: Sparing the aortic valve has become a surgical option for patients who require repair of aortic root ectasia and have normal valve leaflets. Surgical approaches to valve sparing differ with regard to preservation of the native sinuses of Valsalva. The role of the sinuses and the importance of maintaining them remain controversial. METHODS: By using a time-resolved, 3-dimensional, phase-contrast magnetic resonance imaging technique, aortic root and aortic blood velocity data were acquired from 2 patients with Marfan syndrome 6 months after aortic valve-sparing surgery with straight Dacron grafts and contrasted with data from 6 normal volunteers. RESULTS: In normal aortas vortical blood flow became apparent in the individual sinuses after peak systole. The vortices filled the available space behind the valve leaflets and persisted until diastole, expanding and moving inward during aortic valve closure. In contrast, no vortices were observed in the postoperative patients with Marfan syndrome with negligible sinuses. CONCLUSIONS: Changes in supravalvular flow accompany loss of sinus architecture. Whether the presence, size, and velocity of supravalvular vortices affects the function or durability of the preserved aortic valve remains to be studied.  相似文献   
106.
A novel protein MGC5306 has been identified in yeast-two-hybrid analysis by screening a HeLa cDNA library with a truncated DNA polymerasebeta (polbetaDelta) as bait. The polbetaDelta is expressed in various types of cancers. Co-immunoprecipitation-Western blot analysis confirms not only its interaction with polbetaDelta but also with wild-type polbeta. Binding to polbeta indicates potential function of MGC5306 in repair pathway. Transfection of cells with MGC5306-GFP and Western blot analysis with anti-MGC5306 antibody reveal its nuclear localization. MGC5306 is expressed in human carcinomas and tumor cell lines but not in normal tissues, suggesting MGC5306 is most likely involved in carcinogenesis. An antigrowth activity and modulations of cell cycle events are identified in cells expressing siRNAMGC5306.  相似文献   
107.
OBJECTIVE: To examine the association between early childhood speech and language disorders and young adult psychiatric disorders. METHOD: In a longitudinal community study conducted in the Ottawa-Carleton region of Ontario, Canada, interviewers administered structured psychiatric interviews to age 19 participants who were originally identified as speech-impaired only, language-impaired, or nonimpaired at age 5. The first stage of the study took place in 1982 when participants were 5 years old, and the latest stage of the study took place between 1995 and 1997 when participants had a mean age of 19 years. This report examines the association between early childhood speech/language status and young adult psychiatric outcome. RESULTS: Children with early language impairment had significantly higher rates of anxiety disorder in young adulthood compared with nonimpaired children. The majority of participants with anxiety disorders had a diagnosis of social phobia. Trends were found toward associations between language impairment and overall and antisocial personality disorder rates. Males from the language-impaired group had significantly higher rates of antisocial personality disorder compared with males from the control group. Age of onset and comorbidity did not differ by speech/language status. The majority of participants with a disorder had more than one. CONCLUSIONS: Results support the association between early childhood speech and language functioning and young adult psychiatric disorder over a 14-year period. This association underscores the importance of effective and early interventions.  相似文献   
108.
As early-onset hypothyroidism produces audiogenic seizure susceptibility (AGS) in rodents, the role of TR alpha 1 and TR beta thyroid hormone receptors in AGS was investigated. AGS occurs in mice lacking specifically TR beta (Thrb(tm1/tm1)) and is marked by early onset and persistence, thereby differing from mouse strains where AGS is age-restricted. Thrb(tm1/tm1) mice display AGS whether on a mixed 129/Sv x C57BL/6J or congenic C57BL/6J background. 27% of wild-type mice on the mixed and 0% on the congenic background exhibited AGS. The inability of Thrb(tm1/tm1) mice to downregulate the response to sustained acoustic stimulation may reside in the brain or in the auditory system itself as Thrb(tm1/tm1) mice also display auditory deficits. The AGS phenotype identifies a novel neurological role for TR beta.  相似文献   
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