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61.
Takashi Ueguchi Yuko Tanaka Seiki Hamada Risa Kawamoto Yuji Ogata Mitsuhiro Matsumoto Hironobu Nakamura Takeshi Johkoh 《Magnetic resonance in medical sciences》2006,5(3):147-150
Air microbubbles have been investigated recently at high magnetic field strength (2 Tesla or greater) as potential MR susceptibility contrast agents. We used a phantom to measure their susceptibility at 1.5 T to clarify their usefulness for this purpose. The phantom, filled with fresh Levovist suspension at 4 different doses (67 to 125 mg/mL), was continuously scanned with a gradient-echo technique at a temporal resolution of 10 s. The transverse relaxation increase (R2*) by microbubbles demonstrated a time course of exponential decay at each dose (time-constant, 39 to 57 s). The dependency of R2* on microbubble volume fraction was linear, with a slope of 89 s-1 per percentage microbubble volume fraction. Our study represents the first step towards applying microbubbles as susceptibility contrast agents at 1.5 T. 相似文献
62.
Zsolt Csenki Anita Risa Dorottya Srkny Edina Garai Ildik Bata-Vidcs Erzsbet Baka Andrs Szekeres Mnika Varga Andrs cs Jeffrey Griffitts Katalin Bakos Ills Bock Istvn Szab Balzs Kriszt Bla Urbnyi Jzsef Kukolya 《Toxins》2022,14(4)
Aflatoxin B1 (AFB1) is a potent mycotoxin and natural carcinogen. The primary producers of AFB1 are Aspergillus flavus and A. parasiticus. Sterigmatocystin (STC), another mycotoxin, shares its biosynthetic pathway with aflatoxins. While there are abundant data on the biological effects of AFB1, STC is not well characterised. According to published data, AFB1 is more harmful to biological systems than STC. It has been suggested that STC is about one-tenth as potent a mutagen as AFB1 as measured by the Ames test. In this research, the biological effects of S9 rat liver homogenate-activated and non-activated STC and AFB1 were compared using two different biomonitoring systems, SOS-Chromotest and a recently developed microinjection zebrafish embryo method. When comparing the treatments, activated STC caused the highest mortality and number of DNA strand breaks across all injected volumes. Based on the E. coli SOS-Chromotest, the two toxins exerted the same genotoxicities. Moreover, according to the newly developed zebrafish microinjection method, STC appeared more toxic than AFB1. The scarce information correlating AFB1 and STC toxicity suggests that AFB1 is a more potent genotoxin than STC. Our findings contradict this assumption and illustrate the need for more complex biomonitoring systems for mycotoxin risk assessment. 相似文献
63.
Veronica M. LoFaso MD MSN Risa Breckman LCSW Carol F. Capello PhD Byron Demopoulos MD Ronald D. Adelman MD 《Journal of the American Geriatrics Society》2010,58(2):346-351
As the number of people living with chronic illness in the United States rises, it is imperative that medical school prepare physicians who are capable of caring for these patients. This article outlines a creative educational intervention to teach third‐ and fourth‐year medical students about caring for chronically ill people. All students at Weill Medical College, Cornell University, make home visits to homebound older adults with an interdisciplinary team as part of a mandatory Primary Care Clerkship. Under their guidance, students observe the myriad challenges facing homebound older adults. Afterward, students create a project, using original or found art, to express their reactions and thoughts. Students present projects to peers in a small group, with multidisciplinary faculty mentors framing the discussion. To evaluate the intervention, students responded to a nine‐item questionnaire and a series of open‐ended questions. Quantitative and qualitative analyses show consistently strong positive responses to the experience. Most students (95.0%) felt that they learned about the complexities of chronic illness care from their home visits. The opportunity to express reactions through a creative project received positive responses with 97.0% of students responding favorably. Ninety‐seven percent felt that the discussions with colleagues and faculty increased knowledge of chronic illness care. Nearly all (97.0%) felt they had a better understanding of team and that attitudes toward the chronically ill were positively affected. The coupling of the creative arts with home visits is an effective tool for teaching about chronic illness and may be a useful model for medical schools interested in expanding their chronic illness curriculum. 相似文献
64.
Health care providers must be aware of the issues involved in using drugs therapies in older patients because older patients are very vulnerable to the adverse effects of drugs. Although more data are needed to guide clinical decision making in prescribing drugs to older patients, some simple considerations can make drug use safer and more effective (Table 10). Careful, compassionate attention to these factors can have a profound effect on improving the quality of life, medication use, and the overall cost of health care in this vulnerable population. 相似文献
65.
Somes GW Kritchevsky SB Shorr RI Pahor M Applegate WB 《American journal of epidemiology》2002,156(2):132-138
The relation between relative weight and health differs between young and old. In older populations, weight change may cloud the association between a single relative weight and health outcomes. To determine whether weight or weight change is a more important determinant of mortality in a population of older adults, the authors analyzed data from the Systolic Hypertension in the Elderly Program (1984-1990), a randomized clinical trial testing the efficacy of antihypertensive drug treatment to reduce the risk of stroke in older adults (aged 60 years or more) with isolated systolic hypertension. After adjustment for covariates, an average annualized weight loss of at least 1.6 kg/year (odds ratio = 4.9), a weight loss between 1.6 and 0.7 kg/year (odds ratio = 1.7), a weight gain of more than 0.5 kg/year (odds ratio = 2.4), and a baseline body mass index of less than 23.6 (odds ratio = 1.4) all had a significant (p < 0.05) association with all-cause mortality compared with a referent group that was weight stable and of intermediate body mass index (23.6 to <28.0 kg/m(2)) and weight change (-0.7 to <0.5 kg/year). The authors conclude that, in older adults, dynamic measures (e.g., annualized weight change) of weight change predict mortality better than do static weight measures (e.g., baseline body mass index). Even in those with high or low baseline body mass index, weight stability is associated with a lower mortality risk. 相似文献
66.
Eyelid reconstruction with hard palate mucosa grafts. 总被引:4,自引:0,他引:4
Hard palate mucosa grafts are an excellent replacement for tarsus and conjunctiva in eyelid reconstruction. Twenty-five eyelids from 18 patients underwent eyelid reconstruction using hard palate mucosa grafts. Patients were treated for a variety of disorders including postblepharoplasty lower eyelid retraction, cicatricial entropion, eyelid retraction secondary to thyroid eye disease, and lagophthalmos following surgery for paralytic ptosis. Surgical results were evaluated, grafts were measured for postoperative shrinkage, and donor site healing was recorded. Several patients had hard palate biopsy specimens evaluated. One of these patients also had a graft biopsied after it had been in place for 3 months. A review of hard palate anatomy and histology and a discussion of surgical technique are presented. 相似文献
67.
Stein RJ Haddock CK Poston WS Catanese D Spertus JA 《Public health reports (Washington, D.C. : 1974)》2005,120(3):266-270
OBJECTIVE: Weight assessment is a critical aid in patient care. It is particularly important in monitoring progression of pregnancies, heart failure status, and when adjusting medications. Although weight is generally determined using a scale, few studies have evaluated the precision of non-household scales. The objective of this study was to assess scale precision across a variety of settings. METHODS: An evaluation of scales from randomly selected primary care clinics (n=30), diabetology/endocrinology clinics (n=7), weight loss facilities (n=25), and fitness centers (n=30) was performed. Assessments were completed on a total of 223 scales: 94 from primary care clinics, 32 from diabetology/endocrinology clinics, 39 from weight loss centers, and 58 from fitness centers. Scales were assessed for condition, location in facility, resting surface, commercial designation, and calibration history. Scale precision was validated using 100 lb. (45.5 kg), 150 lb. (68.3 kg), 200 lb. (90.9 kg), and 250 lb. (113.6 kg) certified weights. RESULTS: Overall, scales demonstrated decreased precision with increased weight. At higher weights, more than 15% of scales were off by more than 6 lbs. (2.3 kg), approximately 1 Body Mass Index (BMI) unit. While facility type was not significant, condition, location in facility, resting surface, commercial designation, and calibration history were significant. CONCLUSIONS: This study demonstrates that many scales used to measure body weight are imprecise and that scales in health care settings are no more precise than those in other facilities. Clinical decisions based on scales that are imprecise have the potential to cause iatrogenic complications in patient care. 相似文献
68.
Dynamic evolution of coagulopathy in the first day of severe sepsis: relationship with mortality and organ failure 总被引:11,自引:0,他引:11
Dhainaut JF Shorr AF Macias WL Kollef MJ Levi M Reinhart K Nelson DR 《Critical care medicine》2005,33(2):341-348
OBJECTIVE: To determine whether changes in coagulation biomarkers during the first day of severe sepsis correlate with progression from single to multiple organ failure and subsequent death. DESIGN: Analysis of secondary endpoints in a prospective, randomized, placebo-controlled, multinational clinical trial (PROWESS). SETTING: The study involved 164 medical centers. PATIENTS: A total of 840 patients who met criteria for severe sepsis and were randomized to receive placebo plus supportive care. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Coagulation biomarkers, prothrombin time, antithrombin activity, and D-dimer and protein C levels were measured, and Sequential Organ Failure Assessment was performed daily. Multiple logistic regression analysis identified baseline antithrombin activity <54% and changes in prothrombin time, D-dimer, and antithrombin activity during the first calendar day after the onset of the first sepsis-induced organ dysfunction (i.e., the first day of severe sepsis, day 1) as predictive of 28-day mortality (p < or = .01). A composite coagulopathy score was determined using points for predetermined levels of change from baseline to day 1. The composite coagulopathy score correlated with progression from single to multiple organ failure (p = .0007), time to resolution of organ failure (p = .0004), and 28-day mortality (p < .0001). Combining the composite coagulopathy score with the Acute Physiology and Chronic Health Evaluation (APACHE) II score improved ability to identify patients who would progress to multiple organ failure (area under receiver operating characteristic curve 0.61 APACHE II vs. 0.65 APACHE II + composite coagulopathy score) and who would die (area under receiver operating characteristic curve 0.69 APACHE II vs. 0.74 APACHE II + composite coagulopathy score). CONCLUSIONS: Continuation or worsening of coagulopathy during the first day of severe sepsis was associated with increased development of new organ failure and 28-day mortality. These results further suggest that coagulation abnormalities contribute to organ failure and death. 相似文献
69.
Kanaya AM Wassel Fyr CL de Rekeneire N Shorr RI Schwartz AV Goodpaster BH Newman AB Harris T Barrett-Connor E 《Diabetes care》2005,28(2):404-408
OBJECTIVE: To create a simple prediction rule that could perform as well as the 2-h postchallenge plasma glucose (PCPG) test to predict those at risk for diabetes. We created a prediction rule in one sample and prospectively validated it for incident diabetes in a separate cohort. RESEARCH DESIGN AND METHODS: A cross-sectional analysis with data from the Rancho Bernardo Study (age 67 +/- 11 years) to derive a rule predicting abnormal PCPG >/=140 mg/dl, using demographic, clinical, and laboratory data of nondiabetic participants with fasting plasma glucose (FPG) <126 mg/dl. Data from the Health, Aging and Body Composition study (age 74 +/- 3 years) were used to prospectively validate this rule for incident diabetes and compare it with the predictive ability of the PCPG test. RESULTS: Of 1,549 RBS participants, 514 (33%) had PCPG >/=140 mg/dl. Female sex, age, triglycerides, and FPG were most significantly associated with abnormal PCPG. Based on standardized beta-coefficients, we allotted 1 point for female sex, triglycerides >/=150 mg/dl, or FPG 95-104 mg/dl. Age >/=70 years or FPG 105-115 mg/dl were given 2 points, and FPG 116-125 mg/dl received 3 points. In the validation cohort, this simple prediction rule was as good as the 2-h PCPG test for predicting incident diabetes (C-statistic: 0.71 for both). CONCLUSIONS: Advanced age, female sex, FPG, and triglycerides were able to predict adults at risk for diabetes equally well as the 2-h PCPG test. Using this rule, clinicians may better identify older persons who should receive intensive lifestyle intervention to prevent type 2 diabetes. 相似文献
70.
Edward Helmick M.F.H. Sheldon I. Miller M.D. Paul Nutting M.D. Gregory Shorr M.D. Lawrence Berg B.A. 《Addiction (Abingdon, England)》1976,71(1):39-43
In 1972 a study was undertaken to evaluate the quality of services being delivered to a population of alcohol abusers. This study focused primarily on the system of health care rather than the outcome of treatment modalities. The results of this study indicated a great deficit in the health care delivery system and therefore a system was devised to help correct this identified deficit. This system is described in detail and is currently being implemented in the state of Alaska. The goals are multiple and include assurance of a minimum standard of care, collection of data which will allow audit of the sytsem and of the health care providers and finally information which will increase our understanding of the types of treatment most effective in the care of a given patient. 相似文献