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991.
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Cancer Causes & Control - We examined associations between the 2010 Affordable Care Act (ACA) provisions, 2011 Advisory Committee on Immunization Practices (ACIP) recommendation, and 2014...  相似文献   
994.
Osteoporosis is a serious public health concern. Understanding the extent to which a bone density assessment affects change in dietary intake in postmenopausal women is needed. This study investigated whether results of bone density screening tests resulted in reported initiation or change in either dietary and/or supplemental calcium intake. Between 1997 and 2000, dual-energy X-ray absorptiometry (DXA) screening was conducted on 1468 postmenopausal women as part of an ancillary study of the Women's Health Initiative Observational Study in Buffalo, New York. One year after bone density testing, a questionnaire was sent to determine change in lifestyle behaviors and dietary intake. Participants included in this analysis were 923 Caucasian women who had not had a prior bone density screening test, reported no prior diagnosis of osteoporosis and were not taking medication (other than hormone therapy) for osteoporosis. Of these, according to WHO T-score criteria, 36% had osteoporosis, 48% had osteopenia, and 17% had normal bone density. Factors associated (P < 0.05) with increase in calcium intake in crude analyses included: BMI, follow-up consultation with a health care provider, and osteopenia or osteoporosis compared with normal T-score level. In multivariate adjusted analyses, both osteopenia [OR = 2.37, 95% CI (1.45-3.89); P = 0.001] and osteoporosis [OR = 3.86, 95% CI (2.30-6.46); P = <0.001] found on DXA were strong independent predictors of women's decision to start or increase calcium intake. This study provided evidence that the results of osteoporosis DXA screening influence postmenopausal women's decisions to increase calcium intake.  相似文献   
995.
The Virtual Mock Loop (VML) is a mathematical model designed to simulate mechanism of the human cardiovascular system interacting with mechanical circulatory support devices. Here, we aimed to mimic the hemodynamic performance of Cleveland Clinic’s self-regulating continuous-flow total artificial heart (CFTAH) via VML and evaluate the accuracy of the VML compared with an in vivo acute animal study. The VML reproduced 124 hemodynamic conditions from three acute in vivo experiments in calves. Systemic/pulmonary vascular resistances, pump rotational speed, pulsatility, and pulse rate were set for the VML from in vivo data. We compared outputs (pump flow, left and right pump pressure rises, and atrial pressure difference) between the two systems. The pump performance curves all fell in the designed range. There was a strong correlation between the VML and the in vivo study in the left pump flow (r2 = 0.84) and pressure rise (r2 = 0.80), and a moderate correlation in right pressure rise (r2 = 0.52) and atrial pressure difference (r2 = 0.59). Although there is room for improvement in simulating right-sided pump performance of self-regulating CFTAH, the VML acceptably simulated the hemodynamics observed in an in vivo study. These results indicate that pump flow and pressure rise can be estimated from vascular resistances and pump settings.  相似文献   
996.
The motion-activated system (MAS) employs vibration to prevent intraluminal chest tube clogging. We evaluated the intraluminal clot formation inside chest tubes using high-speed camera imaging and postexplant histology analysis of thrombus. The chest tube clogging was tested (MAS vs. control) in acute hemothorax porcine models (n = 5). The whole tubes with blood clots were fixed with formalin–acetic acid solution and cut into cross-sections, proceeded for H&E-stained paraffin-embedded tissue sections (MAS sections, n = 11; control sections, n = 11), and analyzed. As a separate effort, a high-speed camera (FASTCAM Mini AX200, 100-mm Zeiss lens) was used to visualize the whole blood clogging pattern inside the chest tube cross-sectional view. Histology revealed a thin string-like fibrin deposition, which showed spiral eddy or aggregate within the blood clots in most sections of Group MAS, but not in those of the control group. Histology findings were compatible with high-speed camera views. The high-speed camera images showed a device-specific intraluminal blood “swirling” pattern. Our findings suggest that a continuous spiral flow in blood within the chest tube (MAS vs. static control) contributes to the formation of a spiral string-like fibrin network during consumption of coagulation factors. As a result, the spiral flow may prevent formation of thick band-like fibrin deposits sticking to the inner tube surface and causing tube clogging, and thus may positively affect chest tube patency and drainage.  相似文献   
997.
The clinical guidelines for interstitial cystitis and related symptomatic conditions were revised by updating our previous guidelines. The current guidelines define interstitial cystitis/bladder pain syndrome as a condition with chronic pelvic pain, pressure or discomfort perceived to be related to the urinary bladder accompanied by other urinary symptoms, such as persistent urge to void or urinary frequency in the absence of confusable diseases. The characteristic symptom complex is collectively referred as hypersensitive bladder symptoms. Interstitial cystitis/bladder pain syndrome is divided into Hunner-type interstitial cystitis and bladder pain syndrome; Hunner-type interstitial cystitis and bladder pain syndrome represent interstitial cystitis/bladder pain syndrome with Hunner lesions and interstitial cystitis/bladder pain syndrome without Hunner lesions, respectively. So-called non-Hunner-type interstitial cystitis featured by glomerulations or bladder bleeding after distension is included in bladder pain syndrome. The symptoms are virtually indistinguishable between Hunner-type interstitial cystitis and bladder pain syndrome; however, Hunner-type interstitial cystitis and bladder pain syndrome should be considered as a separate entity of disorder. Histopathology totally differs between Hunner-type interstitial cystitis and bladder pain syndrome; Hunner-type interstitial cystitis is associated with severe inflammation of the urinary bladder accompanied by lymphoplasmacytic infiltration and urothelial denudation, whereas bladder pain syndrome shows little pathological changes in the bladder. Pathophysiology would also differ between Hunner-type interstitial cystitis and bladder pain syndrome, involving interaction of multiple factors, such as inflammation, autoimmunity, infection, exogenous substances, urothelial dysfunction, neural hyperactivity and extrabladder disorders. The patients should be treated differently based on the diagnosis of Hunner-type interstitial cystitis or bladder pain syndrome, which requires cystoscopy to determine the presence or absence Hunner lesions. Clinical studies are to be designed to analyze outcomes separately for Hunner-type interstitial cystitis and bladder pain syndrome.  相似文献   
998.
The aim of this study was to investigate the information needs among patients with ovarian cancer and whether these information needs change over time. The information needs were evaluated three times, through structured interviews, and were based on the paired comparison approach developed by Degner and colleagues. A consecutive sample of patients (n = 82) with recently diagnosed ovarian cancer was asked to participate. Sixty-four patients (78%) chose to participate. The three different measurements of participants' information needs revealed only small changes in these needs. The three most important information needs, in all measurements, were information about the likelihood of cure, information about the stage and spreading of the disease, and information about different treatment options. Information regarding sexual attractiveness was the lowest ranked item in all measurements. Regarding subgroups (age, education) the only significant difference throughout all measurements was that younger patients rated issues of sexual attractiveness higher than older patients (p = 0.005). In this longitudinal study patients with ovarian cancer ranked information about the disease and its treatment (i.e. likelihood of cure, stage of disease, and treatment options) highest, and information about psychosocial aspects and self-care lowest. These findings are in accordance with the results from studies of women diagnosed with other types of cancer, which used the same methodology.  相似文献   
999.
Modification of recombinant human interleukin-2 (IL-2) with polyethylene glycol (PEG-IL-2) decreases clearance and might favor absorption into the lymphatics, due to its increased molecular weight. In the present study, we compared the plasma and lymph concentrations of IL-2 and PEG-IL-2 in Yorkshire pigs. The IL-2 regimens were i.v. bolus (0.1-1.6 x 10(6) I.U., MIU/kg), 15-min i.v. infusion (0.1 MIU/kg), or s.c. bolus (0.1-3.0 MIU/kg). The PEG-IL-2 doses were 15-min i.v. infusion (0.01 MIU/kg) or s.c. bolus (0.01-0. 10 MIU/kg). Lymph and plasma data were analyzed using noncompartmental methods and NONMEM. Bioavailability of IL-2 was route- and dose-dependent. Bioavailability of i.v. bolus doses of >/=0.16 MIU/kg was complete but only 39% at 0.1 MIU/kg. For the infusion and s.c. doses, bioavailability was 28 and 42%, respectively. Noncompartmental and NONMEM estimates of clearance and volume of distribution at steady state agreed: 300 ml/h/kg and 570 ml/kg, respectively, for IL-2. The ratio of the area under the curve in lymph and plasma increased from 0.67 to 3.4 when comparing i.v. and s.c. routes, and the s.c. delivery advantage (ratio of dose-normalized ratio of the area under the curve in lymph after s.c. and i.v. administration) was 6.6 to 16. For PEG-IL-2, bioavailability was 100%, clearance was 5.9 ml/h/kg, and volume of distribution at steady state was 370 ml/kg. The ratio of the area under the curve in lymph and plasma increased from 0.33 (i.v.) to 1. 2 (s.c.), and the s.c. delivery advantage was 3.8. Subcutaneous dosing would be favored over i.v. dosing, and IL-2 would be favored over PEG-IL-2 to maximize lymph and minimize plasma exposure. Because IL-2 efficacy may be related to lymph concentrations, dosing regimens can now be designed to test this hypothesis.  相似文献   
1000.
Although prior studies have examined the frequency content of local electrogram characteristics during fibrillation, little is know about the effects of underlying heart disease on these parameters. This study was designed to compare the frequency content of local electrograms during VF in canine models of acute ischemia, subacute infarction, and chronic myocardial infarction (MI) to those in control animals to test the hypothesis that underlying heart disease can alter the basic characteristics of VF. VF was induced using burst pacing in three groups of mongrel dogs. Five dogs were evaluated 8 weeks after LAD occlusion MI, five were evaluated 5 days after experimental MI, and 5 had VF induced before (control) and immediately after LAD occlusion (ischemia). During VF, unipolar electrograms were recorded from 112 sites on the anterior LV and electrograms were evaluated 15 and 30 seconds after VF initiation in each group. Electrograms were analyzed by fast Fourier transform. No significant time dependent changes in VF characteristics were noted. The peak frequency was highest in control animals and 8-week MI, intermediate in 5-day MI, and lowest in acute ischemia (P < 0.01 for pairwise comparisons). In contrast, the fractional of energy within a bandwidth of 25% peak amplitude was highest in acute ischemia, (P < 0.001) and similar in the other three groups. Infarction decreased total energy by approximately 50%. In conclusion, the pressure of ischemia or infarction alters the frequency content of VF in a complex fashion. In addition to decreasing the peak frequency, the shape of the power spectral curve is altered in models of structural heart disease. These results suggest that the electrophysiological changes produced by infarction or ischemia alter the structural organization of ventricular fibrillation.  相似文献   
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