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101.
102.
Timothy J Beebe Stephen E Asche Patricia A Harrison Kathryn B Quinlan 《The Journal of adolescent health》2004,35(2):116-123
PURPOSE: To profile adolescent Internet chat room users in terms of demographic characteristics, psychological and environmental factors, and behavioral risk factors. METHODS: The study sample was drawn from respondents to an anonymous statewide survey of 50,168 9th-grade public school students and included 40,376 students who reported Internet access at home and 19,511 who accessed chat rooms. Data were collected by the Minnesota Student Survey (MSS), a survey that has been administered triennially by the state's education department to public school students in grades 6, 9, and 12 since 1989. The MSS includes more than 117 questions (300 variables) addressing attitudinal, behavioral, and environmental issues. Data analysis consisted of comparing the odds of a particular characteristic or behavior for chat room users with that of nonusers. Analyses were run separately for boys and girls. The homogeneity of odd ratios was tested with the Breslow-Day statistic using SPSS for Windows. RESULTS: For boys and girls, use of Internet chat rooms was associated with psychological distress, a difficult living environment, and a higher likelihood of risky behaviors. Although most chat room users did not report serious problems, this group included a disproportionate number of troubled individuals. CONCLUSIONS: Because chat room use serves as an indicator of heightened vulnerability and risk-taking, parents and others need to be aware of potential dangers posed by online contact between strangers and youth. 相似文献
103.
Martin Krause Wolfgang Fogel Volker Tronnier Sabine Pohle Konstanze H?rtnagel Ute Thyen Jens Volkmann 《Movement disorders》2006,21(12):2255-2257
Pantothenate kinase-associated neurodegeneration (PKAN) is a rare autosomal recessive disorder with onset in childhood and rapid progression. There is no causative and insufficient symptomatic drug therapy. Deep brain stimulation (DBS) of the internal pallidum (GPi) has been reported to improve motor function. Most case reports, however, are limited to short observational periods. The impact of DBS on the progression and life expectancy in PKAN is unknown. We present a 5-year outcome and video documentation of bilateral GPi-DBS of an adolescent patient suffering from genetically defined PKAN. 相似文献
104.
Detection of Human T-Lymphotropic Virus (HTLV) tax Sequences in New York City Blood Donors Seronegative for HTLV Types 1 and 2
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Charlene S. Dezzutti Patricia C. Guenthner Sylvester Daniel Ursula Utz Thania Cabrera James H. Marshall Celso Bianco Renu B. Lal Elliot P. Cowan 《Clinical and Vaccine Immunology : CVI》2003,10(4):715-717
A potential public health concern is the reported detection of the human T-lymphotropic virus (HTLV) tax gene in the lymphocytes of up to 11% of a low-risk group of New York City blood donors (NYBD). This study aimed to independently confirm the prevalence of HTLV tax sequences in 293 NYBD. All NYBD tested negative for antibodies to HTLV types 1 and 2 and HTLV Tax. HTLV tax sequences were not detected in the NYBD lymphocytes. These data demonstrate the lack of HTLV-1 tax in this group of NYBD at low risk for HTLV infection. 相似文献
105.
Patricia A. Ludowyk David O. Willenborg Christopher R. Parish 《Journal of neuroimmunology》1992,37(3):237-250
Using experimental autoimmune encephalomyelitis (EAE) in the rat as a model of central nervous system (CNS) inflammation, activated and quiescent T lymphocytes with different antigen specificities were labelled with the fluorescent dye Hoechst 33342 and tested by fluorescence microscopy for their ability to accumulate in different regions of the spinal cord and in other organs at varying times post inoculation. With this highly sensitive assay it was found that activated myelin basic protein (MBP)-specific T cell lines accumulated in the spinal cord (a 1000-fold increase in the lumbar/sacral region by day 4) and caused clinical signs of EAE. In contrast, interleukin-2 (IL-2)-maintained (quiescent) MBP-specific T cell lines failed to accumulate in the CNS and cause disease. Activated ovalbumin (OA)-specific and purified protein derivative of tuberculin (PPD)-specific T cell lines were also found at significantly higher levels in the spinal cord than non-activated cells although they failed to accumulate to a substantial degree when injected alone. When injected with activated MBP-specific T cells the activated OA- and PPD-specific cell lines accumulated in the spinal cord following initial accumulation of the MBP-specific cells, demonstrating that during the inflammatory process there is considerable non-specific recruitment of cells into the inflammatory site. CNS accumulation of activated MBP-specific T cell lines occurred 1-2 days later in irradiated animals than in non-irradiated recipients. This was consistent with irradiated animals also exhibiting a later onset of disease and suggests that irradiation may directly affect the endothelium in a way that makes it less adhesive. In conclusion, this study demonstrates that activated lymphocytes of any specificity enter the spinal cord, and that the neuro-antigen specific cells accumulate there and lead to the recruitment of other cells. Non-activated cells, even those with neural antigen specificity fail to enter the cord. Understanding the nature of what an 'activated' lymphocyte is may allow us to design strategies to inhibit such immune-mediated inflammation. 相似文献
106.
The cholesterol-fed rat model has been used to examine the distribution of radiolabeled cholesterol by whole-body autoradiographic and quantitative videodensitometric methods. Animals were fed a hypercholesterolemic diet for 7 days, and were subsequently killed at 3, 6, 12, 24, or 72 h following a single oral dose of [14C]cholesterol. Maximum blood and tissue levels were observed at 12 h, while liver and adrenals were the most intensely labeled tissues. Liver maintained consistently high levels over the course of the study, while activity in other tissues declined moderately by 72 h, indicating the long half-life of cholesterol radioequivalents in tissue. The results of these experiments suggest that autoradiographic examination of cholesterol distribution in animals treated with pharmaceutical agents designed to modify cholesterol absorption or clearance will be useful in providing supplemental or confirmatory information on the drugs' mode of action. 相似文献
107.
We have described two children with multiple cutaneous granular cell tumors (GCT) and have reviewed the literature. Multiple tumors of the skin are relatively rare, especially in children, with only 18 pediatric cases previously reported. Surgical excision of rapidly growing or symptomatic lesions is the treatment of choice. In these two children with multiple GCT, three lesions were excised. Specific stains for enolase and S-100 protein clearly demarcated tumor margins after surgical excision. Despite intensive investigation, the histogenesis of this tumor is still in dispute. The most tenable theory at this time is that these tumors are derived either directly from Schwann cells or from undifferentiated cells developing neural characteristics. 相似文献
108.
Susan R. Gartner Catherine L. Gilliss Julie A. Shinn Patricia A. Sparacino Sally Rankin Maribelle Leavitt Martha Price Mark Hudes 《Journal of advanced nursing》1988,13(5):649-661
To enhance individual and family health during recovery from heart surgery, this study employed nursing interventions based on self-efficacy and family stress theory during the hospitalization period and for 3 months thereafter. The effectiveness of the interventions were assessed through a randomized trial in which 67 prospective bypass and valve surgery patients, aged 30-77 years, and their spouses, were allocated either the experimental interventions or usual care and followed for 6 months. At 3 months post-surgery, the only statistically significant differences between the experimentals and controls were on perceived self-efficacy for lifting and tolerating emotional distress. At 6 months no significant differences were found on individual or family measures. Analyses revealed that age, gender and preoperative cardiac status significantly affected individual recovery. The study is continuing with a larger sample in order to explicate the recovery process and to better determine whether a low intensity nursing intervention can effect changes in individual and family recovery. 相似文献
109.
Patricia Aikins Murphy Jane Mashburn Barbara W. Graves Mickey Gillmor-Kahn 《Journal of Midwifery & Women's Health》1992,37(6):404-410
This article reviews the normal hematologic changes in pregnancy and the kinetics of iron metabolism. The differences between iron depletion and anemia are described. The hematocrit levels of a nurse-midwifery caseload in a tertiary-care setting are described and compared with recently published population norms. Hematocrits of the sample compared favorably to the population hematocrits until 24 weeks' gestation, when the sample hematocrit mean became statistically lower and remained that way throughout pregnancy. Further analysis was done on the sample hematocrits, comparing differences in parity, age, pregnancy spacing, and AS versus AA hemoglobin. Parous women with a pregnancy interval >12 months had a higher mean hematocrit then nulliparous women. Mean hematocrits of age groups varied significantly only at the 29–32-week interval, with women younger than 18 having lower mean hematocrits than those ≥18. A trend of women with AS hemoglobin having higher hematocrits than women with AA hemoglobin was identified, reaching statistical significance at the 29–32-week interval. 相似文献
110.
V C Herson C Block L I Eisenfeld E Maderazo P J Krause 《American journal of perinatology》1992,9(4):285-288
The ability of the neonate to mount an adequate polymorphonuclear leukocyte (PMN) response, either quantitatively or functionally, is impaired. To assess whether neonatal PMN number and function are altered by labor and delivery, three groups of infants were studied: cesarean section without labor (10), cesarean section after labor (10), and vaginal delivery (11). PMN counts were higher in the groups undergoing labor (p less than 0.01) compared with the cesarean section without labor group. Similarly, the labor groups had evidence of complement activation (increased C3a desarg) compared with the cesarean section without labor group. No differences were noted between the groups in measures of PMN motility (chemokinesis or chemotaxis) or PMN degranulation (plasma lysozyme), suggesting that normal labor and delivery does not contribute to the general PMN dysfunction of the neonate. 相似文献