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1.
Carcinogenesis, 25, 229–235, 2004 We reported the association of  相似文献   
2.
Humans are environmentally and occupationally exposed to polycyclic aromatic hydrocarbons (PAH). PAH's are a class of tumorigenic compounds which act through metabolic transformation to chemically reactive forms, epoxides, which covalently bind to DNA forming DNA adducts. To evaluate the genotoxic effects of PAH's, air and urine samples were analyzed for PAH. Blood samples were analyzed for benzo(a)pyrene-diol-epoxide-DNA (BPDE-DNA) adducts. New methods for analyzing DNA adducts in lymphocytes have been used to study the genotoxic effects of human exposure to carcinogens. BPDE-DNA adducts in lymphocytes have been used as internal dosimeters of exposure to PAH's and several studies have been conducted. We measured BPDE-DNA adducts in aluminium plant workers with immuno-assay and physico-chemical methods. PAH-DNA adducts were detectable to a lesser extent in subjects working in an aluminium plant compared to subjects working in a coke oven plant.  相似文献   
3.
Postmenopausal women enrolled in the Iowa portion of the postmenopausal estrogen/progestin interventions randomized clinical trial (n= 105) during 1989–1991 were studied for (i) the prevalence of human papillomavirus (HPV) in this older age population (ages 45–64), and (ii) the association between hormone replacement therapies (HRTs) and changes in detection of HPV over a 2-year time period. HPV is causative in most cervical and some other genital cancers and in the presence of steroid hormones has been shown to increase neoplastic transformation by HPVin vitro.Using PCR to detect HPV DNA, the overall frequency of the virus regardless of time period was 50.3% (n= 53) with a baseline (BL) frequency of 38.1% and the second year follow-up (FU) of 22.9%. The oncogenic types HPV-16 (75.5%) and HPV-31 (20.8%) were the most commonly reported. All those with persistently detected infection (10.5%), defined as HPV+ at both BL and FU, were identified with HPV-16 or -18. Between these two time periods there were no significant differences in HPV frequency between the placebo and combined HRT groups (BL−/FU+, 21% vs 18%; BL+/FU−, 71% vs 80%). While the study is based on a small sample, the findings suggest that short-term use of HRTs is not associated with an increased risk of HPV detection, but assessment of effects from long-term use is needed. The data also indicate that the frequency of HPV found in older women is higher than previously suspected but that short-term changes in HPV detected in this age group are unrelated to the development of precancerous cervical lesions.  相似文献   
4.
X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG repeat expansion in the first exon of the androgen receptor (AR) gene. Disease-associated alleles (37-66 CAGs) change in length when transmitted from parents to offspring, with a significantly greater tendency to shift size when inherited paternally. As transgenic mice carrying human AR cDNAs with 45 and 66 CAG repeats do not display repeat instability, we attempted to model trinucleotide repeat instability by generating transgenic mice with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions in their genomic context. Studies of independent lines of AR YAC transgenic mice with CAG 45 alleles reveal intergenerational instability at an overall rate of approximately 10%. We also find that the 45 CAG repeat tracts are significantly more unstable with maternal transmission and as the transmitting mother ages. Of all the CAG/CTG repeat transgenic mice produced to date the AR YAC CAG 45 mice are unstable with the smallest trinucleotide repeat mutations, suggesting that the length threshold for repeat instability in the mouse may be lowered by including the appropriate flanking human DNA sequences. By sequence-tagged site content analysis and long range mapping we determined that one unstable transgenic line has integrated an approximately 70 kb segment of the AR locus due to fragmentation of the AR YAC. Identification of the cis - acting elements that permit CAG tract instability and the trans -acting factors that modulate repeat instability in the AR YAC CAG 45 mice may provide insights into the molecular basis of trinucleotide repeat instability in humans.   相似文献   
5.
Abstract Data on the metabolic responses to repeated endurance exercise sessions are limited. Thus, the aims of this study were to examine (1) the impact of prior exercise on metabolic responses to a subsequent exercise session and (2) the effect of different recovery periods between two daily exercise sessions on metabolic responses to the second bout of exercise. Nine male elite athletes participated in four 25-h trials: one bout of exercise (ONE), two bouts of exercise separated by 3 h of rest and one meal (SHORT), two bouts of exercise separated by 6 h of rest and two meals (LONG), and a trial with no exercise (REST). All exercise bouts consisted of 10 min cycling at 50% followed by 65 min at 75% of maximal O2 uptake. Compared to no prior exercise (ONE), a previous bout of exercise (SHORT) was followed by higher mean O2 uptake, heart rate (HR), rectal temperature (TR), excess post-exercise oxygen consumption and lower respiratory exchange ratio (R) during and after a similar exercise session 3 h later. A longer rest interval between the two exercise bouts (6 h versus 3 h) and an additional meal resulted in a decrease in O2 uptake, HR, TR and an increase in R during the second bout of exercise, but no effects on post-exercise metabolism were found. Thus, augmented metabolic stress was observed when strenuous exercise was repeated after only 3 h of recovery, but this was attenuated when a longer recovery period including an additional meal was provided between the exercise sessions.  相似文献   
6.
Summary Objective: This study investigated the prevalence and nature of generalized anxiety symptoms in women who were eight weeks postpartum. Method: A community-based sample of 68 postpartum women completed an interview assessing generalized anxiety disorder and depression and a self-report measure of worry associated with concerns relevant to postpartum women. Results: Three women (4.4%) met DSM-IV criteria for generalized anxiety disorder, and an additional 19 women (27.9%) endorsed subsyndromal difficulties with generalized anxiety. Approximately one third of these women endorsed symptoms of depression. In contrast, only two woman met criteria for major depressive disorder. Conclusion: Postpartum generalized anxiety has a higher prevalence than postpartum depression. Received February 26, 2002; accepted November 11, 2002 Published online January 31, 2003 Acknowledgement This work was supported by a New Faculty Scholar Award and a Graduate Research Fellowship from the University of North Dakota. The authors would like to express their appreciation to Jennifer Brendle, Peter Schmutzer, Talia Tweten, and Chad Lystad for their assistance with this research. Correspondence: Amy Wenzel, Ph.D., Department of Psychology, University of North Dakota, Grand Forks, ND 58202-8380, U.S.A.; e-mail: amy_wenzel@und.nodak.edu  相似文献   
7.
A whole-cell pertussis vaccine, each dose consisting of 250 microg of protein, was given intranasally four times at weekly intervals to six adult volunteers. All vaccinees responded with increases in nasal fluid IgA antibodies to Bordetella pertussis whole-cell antigen. Three vaccinees with high nasal antibody responses also developed increased serum IgA and IgG antibodies to this antigen. Salivary antibody responses to the whole-cell antigen, as well as antibodies in serum and secretions to pertussis toxin (PT) and filamentous haemagglutinin (FHA) were negligible, except for a moderate increase in nasal fluid antibodies to FHA. Unexpectedly, the same vaccinees developed significant rises in nasal and salivary IgA antibodies to meningococcal outer-membrane antigens, whereas corresponding serum IgA and IgG antibodies were unchanged. Thus it appears that mucosal immunisation may induce secretory antibodies with broader specificities than can be found in serum.  相似文献   
8.
The COVID‐19 pandemic necessitated a rapid transition from in‐person office visits to virtual visits in the Down syndrome specialty program at Massachusetts General Hospital (MGH DSP). We describe the clinic transition to virtual visits in April 2020 and reflect on our six‐month experience in virtual visits. Clinic metrics were tracked. Electronic survey responses were collected from caregivers attending virtual visits. Input from the MGH DSP team was collected. From April to September 2020, we maintained patient volume (45 visits per month) and overall satisfaction score (6.7 out of 7) following a sudden, unanticipated transition to virtual visits. Survey of 17 caregivers attending virtual visits found that most were equipped with technology, had access to a private location, and most were able to access visit without any limitations. Caregivers appreciated the convenience of virtual visits but sometimes missed the personal connection of an in‐person visit. Overall, though, virtual visits were frequently viewed as no different than office visits. Team members identified benefits and challenges of virtual visits, as well as lessons learned from this transition. We were able to maintain multidisciplinary, specialty care with optimal caregiver feedback and sustained number of patient visits.  相似文献   
9.
BackgroundThe frequency with which sensory disturbances occur in patients with radicular leg pain and disc herniation is not well known, and the efficacy of tests to identify such changes are not firmly established. The presence of sensory disturbances is a key sign of nerve root involvement and may contribute to the diagnosis of a lumbar disc herniation, identify patients for referral to spinal imaging and surgery, and improve disease classification.Questions/purposesIn this study, we sought: (1) to determine the frequency with which abnormal sensory findings occur in patients with lumbar disc herniation–related radicular pain, using a standard neurological sensory examination; (2) to determine what particular standard sensory test or combination of tests is most effective in establishing sensory dysfunction; and (3) to determine whether a more detailed in-depth sensory examination results in more patients being identified as having abnormal sensory findings.MethodsBetween October 2013 and April 2016, 115 patients aged 18 to 65 years referred to secondary health care with radicular leg pain and disc herniation were considered potentially eligible for inclusion in the study. Based on these inclusion criteria, 79% (91) were found eligible. Ten percent (11) were excluded because of other illness that interfered with the study purpose, 3% (3) because of cauda equina syndrome, 2% (2) because of spinal stenosis, 2% (2) because of prior surgery at the same disc level, and 2% (2) because of poor Norwegian language skills. Three percent (4) of the patients did not want to participate in the study. Of the 91 eligible patients, 56% (51) consented to undergo a comprehensive clinical examination and were used for analysis here. The sample for the purposes of the present study was predetermined at 50. These patients were first examined by a standard procedure, including sensory assessment of light touch, pinprick, vibration, and warmth and cold over the back and legs. Second, an in-depth semiquantitative sensory testing procedure was performed in the main pain area to assess sensory dysfunction and improve the detection of potential positive sensory signs, or sensory gain of function more precisely. Sensory loss was defined as sensations experienced as distinctly reduced in the painful side compared with the contralateral reference side. In contrast, sensory gain was defined as sensations experienced as abnormally strong, unpleasant, or painful and distinctly stronger than the contralateral side. Ambiguous test results were coded as a normal response to avoid inflating the findings. The proportions of abnormal findings were calculated for each sensory modality and for all combinations of the standard examination tests.ResultsThe standard examination identified at least one abnormal finding in 88% (45 of 51) of patients. Sensory loss was present in 80% (41), while sensory gain was present in 35% (18). The combination of pinprick and light touch identified all patients who were classified as having abnormal findings by the full standard examination. The semiquantitative procedure identified an additional three patients with an abnormal finding.ConclusionWe suggest that the combination of pinprick and light touch assessment is an adequate minimal approach for diagnostic and classification purposes in patients with lumbar radicular pain.Level of EvidenceLevel I, diagnostic study.  相似文献   
10.
Solid organ transplant (SOT) recipients run a high risk for adverse outcomes from COVID-19, with reported mortality around 19%. We retrospectively reviewed all known Swedish SOT recipients with RT-PCR confirmed COVID-19 between March 1 and November 20, 2020 and analyzed patient characteristics, management, and outcome. We identified 230 patients with a median age of 54.0 years (13.2), who were predominantly male (64%). Most patients were hospitalized (64%), but 36% remained outpatients. Age >50 and male sex were among predictors of transition from outpatient to inpatient status. National early warning Score 2 (NEWS2) at presentation was higher in non-survivors. Thirty-day all-cause mortality was 9.6% (15.0% for inpatients), increased with age and BMI, and was higher in men. Renal function decreased during COVID-19 but recovered in most patients. SARS-CoV-2 antibodies were identified in 78% of patients at 1–2 months post-infection. Nucleocapsid-specific antibodies decreased to 38% after 6–7 months, while spike-specific antibody responses were more durable. Seroprevalence in 559 asymptomatic patients was 1.4%. Many patients can be managed on an outpatient basis aided by risk stratification with age, sex, and NEWS2 score. Factors associated with adverse outcomes include older age, male sex, greater BMI, and a higher NEWS2 score.  相似文献   
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