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51.
BACKGROUND: Obstructive lung disease and lung cancer are tobacco-related diseases that can remain clinically silent until late in the disease process. We sought to define the risk for incident lung cancer among a national cohort of US adults with and without obstructive lung disease. METHODS: We studied participants in the First National Health and Nutrition Examination Survey, who had up to 22 years of follow-up. We classified subjects as having moderate or severe obstructive lung disease at baseline if the ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC) was less than 70% and the FEV1 was less than 80% of the predicted value. We also determined incident cases of lung cancer during the follow-up period. RESULTS: A total of 113 lung cancers occurred in the 5402 adults in the cohort. In the proportional hazards model adjusted for covariates of age, sex, race, education, smoking status, and duration and intensity of smoking, the presence of moderate or severe obstructive lung disease was associated with a higher risk for incident lung cancer (hazard ratio, 2.8; 95% confidence interval, 1.8-4.4). CONCLUSIONS: The presence of moderate or severe obstructive lung disease is a significant predictor of incident lung cancer in long-term follow-up. This finding may be useful clinically and in studies evaluating the utility of new tools for the early detection of lung cancer.  相似文献   
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Previously, we have demonstrated a novel interaction between Galpha(o) protein and Purkinje cell protein-2 (Pcp2, also known as L7) in vitro and in transfected cells (Luo and Denker [1999] J. Biol. Chem. 274:10685-10688). Pcp2 is uniquely expressed in cerebellar Purkinje cells and in retinal bipolar neurons, and it may function as a cell-type specific modulator for G protein-mediated cell signaling. This interaction has been further evaluated in the present studies. Coimmunoprecipitation experiments reveal that Pcp2 associates with Galpha(o) in vivo in mouse cerebellum and eye extract. Pcp2 also associate with Galpha(i2) in the cerebellum. No detectable associations of Pcp2 with Galpha(z) and Galpha(q) subunits are observed. The association of Galpha(o) and Pcp2 is detected at postnatal day 1 (P1), and the association remains stable from day 3 (P3) until adulthood. Further, immunofluorescent double labeling and confocal microscopy suggest that Pcp2 and Galpha(o) are colocalized in the distal processes of cerebellar Purkinje cells including axonal endings and dendritic spines. Taken together, these findings indicate colocalization and association of Galpha(o) and Pcp2 in cerebellum and suggest a functional role in regions of synaptic activity.  相似文献   
53.
Taylor KL  Shelby R  Kerner J  Redd W  Lynch J 《Cancer》2002,95(5):1037-1044
BACKGROUND: Despite the ongoing controversy regarding the utility of prostate carcinoma (PCa) screening, the prevalence of asymptomatic men who participate in free PCa screening programs is on the rise. However, this increased awareness has not been associated with increased knowledge about the potential limitations of PCa creening. We conducted a prospective assessment to delineate men's motivations for undergoing screening and to determine the impact of screening on psychological distress and on men's knowledge about PCa screening. METHODS: We conducted two telephone interviews with a group of 136 men registered to undergo free PCa screening at two hospital-based sites. The first interview was conducted before screening and the second interview followed receipt of the screening results. Interviews assessed demographics and screening history, reasons for undergoing the current screening, cancer-related and general psychological distress, knowledge of risk factors for PCa, and knowledge of the benefits and limitations of screening. Only participants with normal screening results were included in these analyses. RESULTS: "Seeking peace of mind about prostate cancer" was rated as the most important reason for undergoing screening. PCa-related distress decreased following receipt of a negative result (P < 0.01). Stratified analyses indicated that this was particularly true among younger men and African American men (both Ps < 0.001). Awareness of the benefits of screening was very high, but awareness of limitations was low, with fewer limitations reported following screening compared with prescreening (P < 0.01). Although awareness of the established risk factors improved following screening, controversial risk factors (i.e., those with limited empirical support) and factors that were unrelated to PCa risk were also rated as more important in the development of PCa than they were before screening (all Ps < 0.05). Therefore, the results may reflect that following screening, participants were simply more likely to endorse plausible risk factors, rather than actually reflecting an increase in participants' knowledge. CONCLUSIONS: These results suggest the importance of developing informed consent procedures and educational programs for the asymptomatic men who participate in free prostate screening programs each year, as the decision to be screened is being made without the benefit of a full understanding of the current state of medical knowledge about PCa screening. Until the definitive results of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial are available, improved patient education is needed to assist men in making screening decisions consistent with their own preferences.  相似文献   
54.
Cocaine use in pregnancy in Amsterdam   总被引:1,自引:0,他引:1  
To study the effects of cocaine use in pregnancy in Amsterdam, clinical data on cocaine-using pregnant women ( n = 21) and their offspring ( n = 23) were obtained retrospectively (1987–1994) at the Academic Medical Center, Amsterdam. Infants exposed to cocaine had a median gestational age of 39 weeks and a median birth weight of 3090 g. There were six preterm infants, two small-for-gestational-age infants and five infants with a small head circumference. Three infants had a congenital malformation. One infant (Potter's syndrome) died shortly before birth. One infant had congenital syphilis, four had intracerebral abnormalities on ultrasound and four had abnormal neurologic symptoms in the neonatal period. One infant died after 21 days of life. At follow-up four infants showed abnormal development. In 12 of the 23 infants (52%), one or more possible effects of cocaine were found.  相似文献   
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This longitudinal study examined the relation between life stress and basic beliefs about self-worth and the benevolence and meaningfulness of the world among mothers of children undergoing bone marrow transplantation (BMT). One hundred mothers completed study measures during the child's hospitalization for BMT and 1 year later. Prior trauma and recent negative events were associated with basic beliefs during hospitalization and also with changes in basic beliefs in the subsequent year, with distress mediating some of these relations. Findings also demonstrated relations between basic beliefs and physical and mental functioning. However, each basic belief exhibited different relations with study variables, suggesting the need to investigate them separately.  相似文献   
60.
The Windber Research Institute is an integrated high-throughput research center employing clinical, genomic and proteomic platforms to produce terabyte levels of data. We use biomedical informatics technologies to integrate all of these operations. This report includes information on a multi-year, multi-phase hybrid data warehouse project currently under development in the Institute. The purpose of the warehouse is to host the terabyte-level of internal experimentally generated data as well as data from public sources. We have previously reported on the phase I development, which integrated limited internal data sources and selected public databases. Currently, we are completing phase II development, which integrates our internal automated data sources and develops visualization tools to query across these data types. This paper summarizes our clinical and experimental operations, the data warehouse development, and the challenges we have faced. In phase III we plan to federate additional manual internal and public data sources and then to develop and adapt more data analysis and mining tools. We expect that the final implementation of the data warehouse will greatly facilitate biomedical informatics research.  相似文献   
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