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991.
J. David Yount Joseph E. Richter 《Archives of environmental contamination and toxicology》1986,15(1):51-60
The objectives of this study were to determine the effects of pentachlorophenol (PCP) on the periphyton community in outdoor experimental streams. It was part of a larger study in which an objective was to evaluate the effects of PCP at water quality criterion levels on natural aquatic communities. Measures of periphyton biomass including ash-free dry weight and phytopigments indicated a linear dose-response relationship with PCP between the criterion level (48 g/L) and 432 g/L. Slight effects were evident at the criterion level. 相似文献
992.
Philip Sandblom M.D. Frédéric Saegesser M.D. Velimir Mirkovitch M.D. 《World journal of surgery》1984,8(1):41-50
Hepatic hemobilia is defined as hemorrhage arising from pathological changes in the intrahepatic biliary tract. The main causes are iatrogenic trauma, cholangitis, tumors, and coagulopathy. The salient features of the hemobilia syndrome are described and their causes explained. The treatment, when necessitated by hemorrhage or clot formation, is either resection of the liver or occlusion of the responsible artery by ligature or embolization. The iatrogenic trauma may be operative, resulting from instrumental lesion of the bile ducts, needle biopsy, transhepatic cholangiography, biliary tract prosthesis, or inlaying hepatic artery catheters. Among the inflammatory etiologies, special attention is given to nematodes in the ducts, the tropical hemobilia. Spontaneous hemobilia may, just as nose bleeds or hematuria, result from treatment with anticoagulants.
Résumé L'hémobilie d'origine hépatique répond à l'hémorragie qui provient de lésions situées au niveau des voies biliaires intra-hépatiques. Les causes principales en sont le traumatisme, l'angiocholite, les tumeurs et les troubles de la coagulation. Les caracteres saillants de l'hémobilie sont décrits ainsi que ses causes. Le traitement quand il devient nécessaire en raison de l'importance de l'hémorragie ou de la formation de caillots consiste à réséquer une partie du parenchyme hépatique ou à obtenir l'occlusion de la plaie vasculaire par ligature ou par embolisation.Le traumatisme peut être d'origine iatrogène, qu'il soit le fait d'une lésion instrumentale des canaux biliaires hépatiques, d'une biopsie du foie à l'aiguille, de la cholangiographie transhépatique, ou encore de la présence d'une prothèse au niveau des voies biliaires ou d'un cathéter artériel.Parmi les causes inflammatoires une attention spéciale doit être accordée à l'existence de nématodes au niveau des canaux biliaires intra-hépatiques qui sont à l'origine de l'hémobilie tropicale.L'hémobilie spontanée, comme l'épistaxis ou l'hématurie, peut être la conséquence d'un traitement anti-coagulant.ResumenLa hemobilia hepática se define como hemorragia proveniente de alteraciones patológicas en el tracto biliar intrahepatico. Las causas principales son el trauma iatrogénico, la colangitis, los tumores y la coagulopatía. Se describen las características sobresalientes del síndrome de hemobilia y se explican sus causas. El tratamiento, cuando se hace necesario por hemorragia o por formación de coágulos, es la resección del hígado o la oclusión de la arteria responsable por ligadura o por embolización. El trauma iatrogénico puede ser de origen operatorio, como resultado de lesión instrumental de los canales biliares, biopsia por aguja, colangiografía transhepática, prótesis en el tracto biliar y catéteres colocados en la arteria hepática. Entre las etiologías de naturaleza inflamatoria se presta atención especial a la presencia de nemátodos en los canales, la hemobilia tropical. Al igual de lo que ocurre con las epistaxis o las hematurias, la hemobilia espontanea puede ser consecuencia de tratamientos con anticoagulantes.相似文献
993.
Joseph W. Rachlin Thomas E. Jensen Barbara Warkentine 《Archives of environmental contamination and toxicology》1984,13(2):143-151
The toxicological response of the cyanophycean algaAnabaena flos- aquae to cadmium was investigated by three integrated approaches: 1) the determination of the incipient lethal concentration of the metal, 2) study of metal incorporation and cellular compartmentalization using X-ray energy dispersive analysis, and 3) the quantification of intracellular structural changes, after metal exposure, using morphometric analysis. After 96 hr of exposure, the incipient lethal concentration was calculated to be 0.118 ± 0.04 M cadmium. At concentrations three orders of magnitude higher than the incipient lethal concentration, cadmium was incorporated into both the cellular cytoplasm and the cell's polyphosphate bodies. Cadmium also caused the polyphosphate bodies to lose Mg and Ca, resulting in ionic changes in the elemental composition of these cellular inclusions. The utilization of stereological techniques for electron microscopic morphometric analysis established that all concentrations of cadmium tested caused significant reductions in the surface area of the cell's thylakoids. Cadmium induced changes in the numbers and relative volume of the cell occupied by polyhedral bodies, polyphosphate bodies, lipid inclusions, cyanophycin granules, membrane limited crystalline, inclusions, and changes in the volume of the cell wall layers were also documented. The physiological significance of these findings are discussed in terms of the toxic action of cadmium and the cellular mechanisms for detoxification of cations once they enter the cell. 相似文献
994.
Tanvir S Sian Ushnah S. U. Din Colleen S. Deane Ken Smith Amanda Gates Jonathan N. Lund John P. Williams Ricardo Rueda Suzette L. Pereira Bethan E. Phillips Philip J. Atherton 《Nutrients》2021,13(5)
Ageing is associated with postprandial muscle vascular and metabolic dysfunction, suggesting vascular modifying interventions may be of benefit. Reflecting this, we investigated the impact of acute cocoa flavanol (450–500 mg) intake (versus placebo control) on vascular (via ultrasound) and glucose/insulin metabolic responses (via arterialised/venous blood samples and ELISA) to an oral nutritional supplement (ONS) in twelve healthy older adults (50% male, 72 ± 4 years), in a crossover design study. The cocoa condition displayed significant increases in m. vastus lateralis microvascular blood volume (MBV) in response to feeding at 180 and 240-min after ONS consumption (baseline: 1.00 vs. 180 min: 1.09 ± 0.03, p = 0.05; 240 min: 1.13 ± 0.04, p = 0.002), with MBV at these timepoints significantly higher than in the control condition (p < 0.05). In addition, there was a trend (p = 0.058) for MBV in m. tibialis anterior to increase in response to ONS in the cocoa condition only. Leg blood flow and vascular conductance increased, and vascular resistance decreased in response to ONS (p < 0.05), but these responses were not different between conditions (p > 0.05). Similarly, glucose uptake and insulin increased in response to ONS (p < 0.05) comparably between conditions (p > 0.05). Thus, acute cocoa flavanol supplementation can potentiate oral feeding-induced increases in MBV in older adults, but this improvement does not relay to muscle glucose uptake. 相似文献
995.
Cornelius J Fernandez Annu Susan George Nikhila A Subrahmanyan Joseph M Pappachan 《World Journal of Methodology》2021,11(3):23-45
There exists a complex interaction between obesity, type 2 diabetes mellitus (T2DM) and cancer, and an increase in the incidence of cancer is expected with the growing obesity-diabetes pandemic. The association of cancer with diabetes mellitus and obesity appears to be site-specific, the highest risk being for post-menopausal breast cancer, endometrial cancer, and colorectal cancer. Moreover, there is worsening of hyperglycaemia with the onset of cancer, evidencing a bi-directional link between cancer and diabetes mellitus and the need for monitoring for diabetes in cancer survivors. In this review, we look at the epidemiological evidence from observational studies and Mendelian randomization studies linking obesity, diabetes, and cancer, as well as the complex pathophysiological mechanisms involved, including insulin resistance with associated hyperinsu linaemia, the effect of chronic low-grade inflammation, and the effect of various adipokines that are associated with obesity and T2DM. Additionally, we describe the novel therapeutic strategies, based on their role on the discrete pathophysio logical mechanisms involved in the tumourigenesis. 相似文献
996.
ObjectivesA number of studies have shown an association between smoking habit and quality of life, but these have mainly involved cross-sectional data. This study takes advantage of longitudinal panel data to estimate the effect of the transition from “smoker” to “ex-smoker” status (smoking cessation) on health-related quality of life (HRQoL), measured by SF-36, in an Australian general population sample.MethodsPanel data from 13 waves (2001-2013) of a nationally representative longitudinal survey of Household Income and Labour Dynamics of Australia (HILDA) were used; 1858 respondents (5% of total HILDA sample) who experienced only 1 cessation event in their HILDA life were selected. HRQoL trajectories elicited by SF-36 (0-100 scale, worst to best health) were modeled before and after cessation events using a piecewise (segmented) 2-way fixed-effect linear regression, adopted to capture within-person differences. This enabled measurement of changes of regression slopes and intercept while controlling time-invariant characteristics (eg, country of birth, gender) and time-varying changes in health status.ResultsAnnual pre-post intervention improvements were estimated for the following dimensions: role physical 0.65 (95% CI 0.62-1.24), bodily pain 0.48 (95% CI 0.10-0.86), general health 0.55 (95% CI 0.2-0.9), and the physical component summary score 0.22 (95% CI 0.01-0.04). Immediate effects (discontinuity at the time of cessation) of smoking cessation existed for bodily pain –1.5 (95% CI –2.52 to –0.40) and general health 1.82 (95% CI 1.01-2.62). The effects for mental health domains were not significant.ConclusionsAdjusting for all unmeasured time-invariant confounders and controlling the effect of time, this study revealed the varied effects of smoking cessation on HRQoL; it has positive effect on physical and general health but nonsignificant effect on mental aspects. Preference-based utility measures based on SF-6D capture changes that can be measured in several of the domains of the SF-36. 相似文献
997.
Bradshaw Catherine P. Pas Elise T. Musci Rashelle J. Kush Joseph M. Ryoo Ji Hoon 《Prevention science》2021,22(7):986-1000
Prevention Science - This study examined the impact of a state policy requiring that any school with a habitual truancy rate of 8% or higher to be trained in Tier 1 school-wide Positive Behavioral... 相似文献
998.
Anna Song Beeber Christine E. Kistler Sheryl Zimmerman Cassandra Dictus Kimberly Ward Claire Farel Keith Chrzan Christopher J. Wretman Marcella Boyton-Hansen Michael Pignone Philip D. Sloane 《Journal of the American Medical Directors Association》2021,22(1):156-163
ObjectivesTo determine what information is most important to registered nurses' (RNs) decisions to call clinicians about suspected urinary tract infections (UTIs) in nursing home residents.DesignWeb-based discrete choice experiment with 19 clinical scenarios.Setting and ParticipantsOnline survey with a convenience sample of RNs (N = 881) recruited from a health care research panel.MethodsClinical scenarios used information from 10 categories of resident characteristics: UTI risk, resident type, functional status, mental status, lower urinary tract status, body temperature, physical examination, urinalysis, antibiotic request, and goals of care. Participants were randomized into 2 deliberation conditions (self-paced, n = 437 and forced deliberation, n = 444). The degree to which evidence- and non–evidence-based information was important to decision-making was estimated using unconditional multinomial logistic regression.ResultsFor all nurses (22.8%) and the self-paced group (24.1%), lower urinary tract status had the highest importance scores for the decision to call a clinician about a suspected UTI. For the forced-deliberation group, body temperature was most important (23.7%), and lower urinary tract status was less important (21%, P = .001). The information associated with the highest odds of an RN calling about a suspected UTI was painful or difficult urination [odds ratio (OR) 4.85, 95% confidence interval (CI) 4.16–5.65], obvious blood in urine (OR 4.66, 95% CI 3.99–5.44), and temperature at 101.5° (OR 3.80, 95% CI 3.28–4.42). For the self-paced group, painful or difficult urination (OR 5.65, 95% CI 4.53–7.04) had the highest odds, whereas obvious blood in urine (OR 4.39, 95% CI 3.53–5.47) had highest odds for the forced-deliberation group.Conclusions and ImplicationsThis study highlighted the importance of specific resident characteristics in nurse decision-making about suspected UTIs. Future antimicrobial stewardship efforts should aim to not only improve the previously studied overprescribing practices of clinicians, but to improve nurses' assessment of signs and symptoms of potential infections and how they weigh resident information. 相似文献
999.
Andrew Vipperman Sheryl Zimmerman Philip D. Sloane 《Journal of the American Medical Directors Association》2021,22(5):933-938.e5
ObjectivesAssisted living (AL) emerged over 2 decades ago as a preferred residential care option for older adults who require supportive care; however, as resident acuity increased, concern has been expressed whether AL sufficiently addresses health care needs. COVID-19 amplified those concerns, and an examination of recommendations to manage COVID-19 may shed light on the future of AL. This review summarizes recommendations from 6 key organizations related to preparation for and response to COVID-19 in AL in relation to resident health and quality of life; compares recommendations for AL with those for nursing homes (NHs); and assesses implications for the future of AL.DesignNonsystematic review involving search of gray literature.Setting and ParticipantsRecommendations from key governmental bodies and professional societies regarding COVID-19 in AL, long-term care facilities (LTCFs) in general, and NHs.MeasuresWe collected, categorized, and summarized these recommendations as they pertained to quality of life and health care.ResultsMany recommendations for AL and NHs were similar, but differences provided insight into ways the pandemic was recognized and challenged AL communities in particular: recommending more flexible visitation and group activities for AL, providing screening by AL staff or an outside provider, and suggesting that AL staff access resources to facilitate advance care planning discussions. Recommendations were that AL integrate health care into offered services, including working with consulting clinicians who know both the residents and the LTC community.Conclusions and ImplicationsLong-term care providers and policy makers have recognized the need to modify current long-term care options. Because COVID-19 recommendations suggest AL communities would benefit from the services and expertise of social workers, licensed nurses, and physicians, it may accelerate the integration and closer coordination of psychosocial and medical care into AL. Future research should investigate different models of integrated, interdisciplinary health care in AL. 相似文献
1000.
IntroductionPolycystic ovary syndrome (PCOS) is an endocrine and metabolic condition linked to increased risk of anxiety and depression (psychological distress). This study examined the relationship between illness perceptions and psychological distress in women living with PCOS.MethodsWe used a cross-sectional survey to assess psychological distress (Hospital Anxiety and Depression Scale) and illness perceptions (Illness Perception Questionnaire-Revised) in women living with PCOS in the UK (N = 487). Hierarchical multiple linear regression tested the associations between illness perceptions and psychological distress, adjusting for age, years since PCOS diagnosis, education, body mass index, current depression, and current anxiety disorder.ResultsIn the fully adjusted regression model, illness perceptions explained 18.6% of the variance in psychological distress, F(7,458) = 21.0, p < .001. Reporting more symptoms (B = 0.226), higher perceived consequences (B = 0.204), lower personal control (B = –0.184), and lower illness coherence (B = –0.127) were significantly associated with higher psychological distress (all p < .001).ConclusionsIllness perceptions may play an important role in psychological distress, even after adjusting for relevant demographics and clinical characteristics. Our findings highlight key areas where researchers and clinicians could develop targeted self-management interventions for women with PCOS, focused on altering maladaptive illness perceptions to reduce psychological burden. 相似文献