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71.
Doris M. Bixby-Hammett 《The Physician and sportsmedicine》2013,41(8):82-86
In brief: Head injuries are the most frequent and most severe of all injuries in equestrian sports. It has been estimated that head injuries make up approximately 20% of all horse-related injuries. They can be prevented or their severity can be reduced by wearing properly fitted and secured headgear. A good helmet must be secured from loss, protect the head from the impact or compression of a fall, and resist penetration. The author recommends that the medical community continue to work to make the most protective riding helmet acceptable to the equestrian community. 相似文献
72.
Schaeffer D 《Zeitschrift für Gerontologie und Geriatrie》2004,37(4):307-315
In the following article, two of the increasingly important public health scientific disciplines of care for the elderly are compared under systematic aspects - gerontopsychiatry and nursing science - with the aim of determining the similarities and differences of both disciplines. There follows a discussion of social challenges facing the area of caring for the elderly suffering from psychiatric illnesses and the responsibilities which both disciplines have to cope with in the future. The clearing of the numerous existent geronto-psychiatric deficits in health care in Germany seems to be the main challenge. 相似文献
73.
An endogenous digitalis-factor derived from the adrenal gland: studies of adrenocortical tumor cells
The present studies demonstrate that the murine adrenocortical tumor cell line Y-1 releases a digoxin-like immunoreactive material into both serum-supplemented nutrient medium and minimal Krebs-Ringer bicarbonate medium. Release of pregnenolone into minimal medium from these cells was consistently inhibited by addition of the cholesterol side-chain cleavage inhibitor aminoglutethimide. However, release of digoxin-like immunoreactivity (DLI) was not similarly affected. To exclude the possibility that DLI could be accounted for by cross-reaction with another known adrenal steroid, aminoglutethimide inhibition was accompanied by inhibition of 17 alpha-hydroxylase with SU-10603 and inhibition of 3 beta-hydroxysteroid dehydrogenase with cyanoketone. Once again, pregnenolone release was effectively inhibited, but no similar pattern of inhibition of DLI release was observed. Increasing the time of the incubation periods from 1 to 2 h did not change the pattern of secretion of pregnenolone or DLI. HPLC analysis of DLI released over prolonged culture periods into serum-supplemented nutrient medium showed high levels of DLI in a single major and several adjacent peaks. Analysis of the ability of extracts of Y-1-conditioned medium to compete with tritiated ouabain for binding to erythrocytes indicates that conditioned medium contained highly enriched levels of ouabain-like activity. On HPLC analysis, the distribution of this activity showed partial correlation with the distribution of DLI. These observations indicate that Y-1 cells produce and release significant quantities of a material with cardiac glycoside-like properties reflected in the cross-reactivity with antidigoxin antibodies and the ability to compete with ouabain for binding to erythrocytes. In substantiation of previous findings in chopped adrenal cultures, the cardiac glycoside-like activity does not appear to result from cholesterol side-chain cleavage or pregnenolone production, since inhibition of side-chain cleavage as well as subsequent 17 alpha-hydroxylation and 3 beta-dehydrogenation did not result in consistent inhibition of DLI release. 相似文献
74.
Stem cell carcinoma of the colon and rectum 总被引:2,自引:2,他引:2
Dr. Doris H. B. Palvio M.D. Flemming B. Sørensen M.D. Mogens Kløve-Mogensen M.D. 《Diseases of the colon and rectum》1985,28(6):440-445
Two cases of highly malignant tumors, one originating in the sigmoid colon and the other in the rectum, are presented. Both tumors showed light microscopic, electron microscopic, and immunohistochemical evidence of multidirectional differentiation. The tumors were composed mainly of undifferentiated cells, but focally merging into areas with adenocarcinomatous and squamous differentiation. Ultrastructurally and histochemically, a predominant endocrine differentiation was present in the undifferentiated areas of the tumors. These two cases lend further support to the recent concept of a pluripotential stem cell in the mucosa of the gastrointestinal tract capable of differentiation in several directions. 相似文献
75.
A retrospective review of 67 patients with acute cervical spine fracture and/or dislocation was conducted at two suburban community hospital emergency departments. The mean age was 39, and two-thirds of the patients were male. Motor vehicle accidents and falls accounted for more than 80% of all injuries. On emergency department evaluation, it was found that there was no history of loss of consciousness in 42 patients (63%), no associated cranio-facial injuries in 31 patients (46%), and a normal sensorimotor examination in 59 patients (88%). Thirty-four patients (50%) were evaluated for cervical range of motion, which was found to be normal in one-third of the cases. The absence of mental status changes, cranio-facial injuries, range of motion abnormalities, and focal neurological findings is, therefore, not uncommon in patients who have sustained cervical spine injury. 相似文献
76.
Betzana Zambrano Fernando Noriega Gustavo H. Dayan Doris Maribel Rivera Jos Luis Arredondo Humberto Reynales Kleber Luz Carmen Deseda Matthew I. Bonaparte Edith Langevin Yukun Wu Margarita Corts Stephen Savarino Carlos A. DiazGranados 《The American journal of tropical medicine and hygiene》2021,104(1):136
77.
Kang H. Zheng Sotirios Tsimikas Tania Pawade Jeffrey Kroon William S.A. Jenkins Mhairi K. Doris Audrey C. White Nyanza K.L.M. Timmers Jesper Hjortnaes Maximillian A. Rogers Elena Aikawa Benoit J. Arsenault Joseph L. Witztum David E. Newby Marlys L. Koschinsky Zahi A. Fayad Erik S.G. Stroes S. Matthijs Boekholdt Marc R. Dweck 《Journal of the American College of Cardiology》2019,73(17):2150-2162
Background
Lipoprotein(a) [Lp(a)], a major carrier of oxidized phospholipids (OxPL), is associated with an increased incidence of aortic stenosis (AS). However, it remains unclear whether elevated Lp(a) and OxPL drive disease progression and are therefore targets for therapeutic intervention.Objectives
This study investigated whether Lp(a) and OxPL on apolipoprotein B-100 (OxPL-apoB) levels are associated with disease activity, disease progression, and clinical events in AS patients, along with the mechanisms underlying any associations.Methods
This study combined 2 prospective cohorts and measured Lp(a) and OxPL-apoB levels in patients with AS (Vmax >2.0 m/s), who underwent baseline 18F-sodium fluoride (18F-NaF) positron emission tomography (PET), repeat computed tomography calcium scoring, and repeat echocardiography. In vitro studies investigated the effects of Lp(a) and OxPL on valvular interstitial cells.Results
Overall, 145 patients were studied (68% men; age 70.3 ± 9.9 years). On baseline positron emission tomography, patients in the top Lp(a) tertile had increased valve calcification activity compared with those in lower tertiles (n = 79; 18F-NaF tissue-to-background ratio of the most diseased segment: 2.16 vs. 1.97; p = 0.043). During follow-up, patients in the top Lp(a) tertile had increased progression of valvular computed tomography calcium score (n = 51; 309 AU/year [interquartile range: 142 to 483 AU/year] vs. 93 AU/year [interquartile range: 56 to 296 AU/year; p = 0.015), faster hemodynamic progression on echocardiography (n = 129; 0.23 ± 0.20 m/s/year vs. 0.14 ± 0.20 m/s/year] p = 0.019), and increased risk for aortic valve replacement and death (n = 145; hazard ratio: 1.87; 95% CI: 1.13 to 3.08; p = 0.014), compared with lower tertiles. Similar results were noted with OxPL-apoB. In vitro, Lp(a) induced osteogenic differentiation of valvular interstitial cells, mediated by OxPL and inhibited with the E06 monoclonal antibody against OxPL.Conclusions
In patients with AS, Lp(a) and OxPL drive valve calcification and disease progression. These findings suggest lowering Lp(a) or inactivating OxPL may slow AS progression and provide a rationale for clinical trials to test this hypothesis. 相似文献78.
Dr. Jonathan A. Leighton M.D. Miguel A. Valdovinos M.D. John H. Pemberton M.D. Doris M. Rath R.N. Michael Camilleri M.D. 《Diseases of the colon and rectum》1993,36(2):182-185
Our aim was to characterize the clinical spectrum of anorectal dysfunction among eight patients with progressive systemic sclerosis (PSS) who presented with altered bowel movements with or without fecal incontinence. The anorectum was assessed by physical examination, proctosigmoidoscopy, and anorectal manometry. There was concomitant involvement of the other regions of the digestive tract in all patients as determined by barium studies, endoscopy, or manometry: eight esophageal, three gastric, four small bowel, and two colonic. Seven patients had fecal incontinence, and four also had second-degree complete rectal prolapse. Abnormal anorectal function, particularly abnormal anal sphincter resting pressures, were detected in all patients; anal sphincter pressures were lower in those with rectal prolapse. Rectal capacity and wall compliance were impaired in seven of seven patients. Successful surgical correction of prolapse in three patients resulted in restoration of incontinence for six months and seven years in two of the three patients. We conclude that rectal dysfunction and weakness of the anal sphincters are important factors contributing, respectively, to altered bowel movements and fecal incontinence in patients with gastrointestinal involvement by PSS. Rectal prolapse worsens anal sphincter dysfunction and should be sought routinely as it is a treatable factor aggravating fecal incontinence in patients with PSS.This work was presented in part at the Annual Meeting of the American Gastroenterological Association, May 1992, and appears in abstract form in Gastroenterology 1992;102:A473.Supported in part by the General Clinical Research Center Grant 00585 from the National Institutes of Health. 相似文献
79.
Polydiacetylene Nanotubes in Heterogeneous Catalysis: Application to the Gold‐Mediated Oxidation of Silanes 下载免费PDF全文
Elise Villemin Edmond Gravel Dhanaji V. Jawale Praveen Prakash Irishi N. N. Namboothiri Eric Doris 《Macromolecular chemistry and physics.》2015,216(24):2398-2403
A layer‐by‐layer approach is used to anchor small gold nanoparticles onto organic nanotubes resulting from the self‐assembly and polymerization of diacetylene‐containing nitrilotriacetic amphiphiles. The obtained nanotube–gold hybrid is used as a catalyst for the aerobic oxidation of various silanes. With minimal gold loading (0.05 mol%), all substrates are converted into the corresponding silanols with hydrogen gas as the only by‐product. The catalyst operates under mild conditions and can be easily recycled, losing neither activity nor selectivity.
80.
Jerraco L. Johnson Benjamin Miedema Brooke Converse Doris Hill Alice M. Buchanan Claire Bridges J. Megan Irwin Mary E. Rudisill Melissa Pangelinan 《Journal of developmental and physical disabilities》2018,30(3):427-437
The aim of this study was to compare the influence of two different instructional climates on the accumulation of moderate-to-vigorous physical activity (MVPA) during a fully-inclusive adapted recreational physical activity program. A total of 32 children (18 typically-developing (TD), and 14 with developmental disabilities (DD) ranging in ages from 5 to 9 years, participated in six, 60-min adapted recreational sessions. Of those six sessions, three incorporated an autonomy-supportive climate (high autonomy), and three incorporated direct instruction (low autonomy). MVPA was measured using accelerometers. A repeated measures ANOVA was conducted to determine significant differences in MVPA between group (TD/DD), climate (autonomy/direct), and a group x climate interaction. Significant group and climate main effects were observed (p?=?0.002 and 0.014, respectively). However, there was not a significant group x climate interaction (p?=?0.313). These results suggest that although the group of children with disabilities spent less time in MVPA compared to their typically-developing peers, all participants spent more time in MVPA for the autonomy-supportive climate compared to the low-autonomous climate. This study is the first to quantitatively assess the efficacy of a fully-inclusive autonomy-supportive climate on physical activity levels in children with and without developmental disabilities. 相似文献