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81.
Charles E. Mahan Maxine D. Fisher Roger M. Mills Larry E. Fields Judith J. Stephenson An-Chen Fu Alex C. Spyropoulos 《Thrombosis research》2013
Introduction
Medically ill, hospitalized patients are at increased risk for venous thromboembolism (VTE) after discharge. This study aimed to examine thromboprophylaxis patterns, risk factors, and post-discharge outcomes.Methods
This was a retrospective claims analysis involving administrative claims data and in-patient data abstracted from a sample of hospital charts. Patients aged ≥ 40 years hospitalized for ≥ 2 days for nonsurgical reasons between 2005 and 2009 were included. Hospital chart data were abstracted for a random sample of patients without evidence of anticoagulant use at 30 days post-discharge. The combined data determined whether in-patient thromboprophylaxis (anticoagulant or mechanical prophylaxis) reduces risk of VTE at 90 days post-discharge. Hazard ratios (HR) and odds ratios (OR) were calculated using Cox proportional hazard models and logistic regression.Results
Of 141,628 patients in the claims analysis, 3.9% received anticoagulants (3.6% warfarin). VTE, rehospitalization, and mortality rates were 1.9%, 17.2%, and 6.2%, respectively. The strongest predictors of post-discharge VTE were history of VTE (HR = 4.0, 95% confidence interval [CI]: 3.3-4.8), and rehospitalization (HR = 3.9, 95% CI: 3.6-4.3). Of 504 medical charts, 209 (41.5%) reported in-patient thromboprophylaxis. There was no statistically significant difference in post-discharge VTE rates between patients who did and did not receive in-patient thromboprophylaxis. All-cause mortality was greater among patients without use of VTE prophylaxis.Conclusion
Utilization rates of in-hospital and post-discharge VTE prophylaxis were low. In-hospital VTE prophylaxis did not reduce the risk of post-discharge VTE in the absence of post-discharge anticoagulation. Combined in-patient and post-discharge thromboprophylaxis lowered the odds of short-term, all-cause post-discharge mortality. 相似文献82.
Alexandra?W.?Acher Malcolm?H.?Squires Ryan?C.?Fields George?A.?Poultsides Carl?Schmidt Konstantinos?I.?Votanopoulos Timothy?M.?Pawlik Linda?X.?Jin Aslam?Ejaz David?A.?Kooby Mark?Bloomston David?Worhunsky Edward?A.?Levine Neil?Saunders Emily?Winslow Clifford?S.?Cho Glen?Leverson Shishir?K.?Maithel Sharon?M.?WeberEmail author 《Journal of gastrointestinal surgery》2016,20(7):1284-1294
Background
This study utilized a multi-institutional database to evaluate risk factors for readmission in patients undergoing curative gastrectomy for gastric adenocarcinoma with the intent of describing both perioperative risk factors and the relationship of readmission to survival.Methods
Patients who underwent curative resection of gastric adenocarcinoma from 2000 to 2012 from seven academic institutions of the US Gastric Cancer Collaborative were analyzed. In-hospital deaths and palliative surgeries were excluded, and readmission was defined as within 30 days of discharge. Univariate and multivariable logistic regression analyses were employed and survival analysis conducted.Results
Of the 855 patients, 121 patients (14.2 %) were readmitted. Univariate analysis identified advanced age (p?<?0.0128), American Society of Anesthesiology status ≥3 (p?=?0.0045), preexisting cardiac disease (p?<?0.0001), hypertension (p?=?0.0142), history of smoking (p?=?0.0254), increased preoperative blood urea nitrogen (BUN; p?=?0.0426), concomitant pancreatectomy (p?=?0.0056), increased operation time (p?=?0.0384), estimated blood loss (p?=?0.0196), 25th percentile length of stay (<7 days, p?=?0.0166), 75th percentile length of stay (>12 days, p?=?0.0256), postoperative complication (p?<?0.0001), and total gastrectomy (p?=?0.0167) as risk factors for readmission. Multivariable analysis identified cardiac disease (odds ratio (OR) 2.4, 95 % confidence interval (CI) 1.6–3.3, p?<?0.0001), postoperative complication (OR 2.3, 95 % CI 1.6–5.4, p?<?0.0001), and pancreatectomy (OR 2.2, 95 % CI 1.1–4.1, p?=?0.0202) as independent risk factors for readmission. There was an association of decreased overall median survival in readmitted patients (39 months for readmitted vs. 103 months for non-readmitted). This was due to decreased survival in readmitted stage 1 (p?=?0.0039), while there was no difference in survival for other stages. Stage I readmitted patients had a higher incidence of cardiac disease than stage I non-readmitted patients (58 vs. 24 %, respectively, p?=?0.0002).Conclusions
Within this multi-institutional study investigating readmission in patients undergoing curative resection for gastric cancer, cardiac disease, postoperative complication, and concomitant pancreatectomy were identified as significant risk factors for readmission. Readmission was associated with decreased overall median survival, but on further analysis, this was driven by differences in survival for stage I disease only.83.
Impact of amino acid sequence variation of a determinant(s) on the antigenic properties of hepatitis B virus HBsAg 总被引:1,自引:0,他引:1
Ulanova TI Yokosawa J Puzyrev VF Obriadina AP Burkov AN Khudyakov Y Fields H 《Voprosy virusologii》2007,52(3):13-15
Impact of amino acid sequence variation on the antigenic properties of the surface hepatitis B virus antigen HBsAg was studied. Eleven recombinant HBsAg variants of wild (adr, ayw2, adw2, adw4, aywl, adw2) and vaccine escape (adw2 T126S, adw2 Q129L, adw2 Q129R, adw2 T143K, adw2 Q145R, aywl Q145A) were obtained. All the recombinant antigens were tested on a panel of 43 monoclonal antibodies (MAb) specific to different HBsAg determinants. Amino acid sequence variation of the a-determinant of HBsAg was shown to significantly affect its immunological responsiveness and antigenic properties. Amino acid substitution in different positions or in the same position, but for various amino acids may differently affect these properties. 相似文献
84.
Distinguishing acute from chronic and resolved hepatitis C virus (HCV) infections by measurement of anti-HCV immunoglobulin G avidity index
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Klimashevskaya S Obriadina A Ulanova T Bochkova G Burkov A Araujo A Stramer SL Tobler LH Busch MP Fields HA 《Journal of clinical microbiology》2007,45(10):3400-3403
An assay to measure avidity index (AI) was developed to diagnose incident hepatitis C virus (HCV) infections. The assay demonstrated an AI value statistically significantly lower in primary HCV infections than in chronic infections. When the assay was applied to past resolved infections, the difference in AI values was not as significant as the difference between incident and chronic infections. Lower AI values obtained in past resolved infections may be directly related to lower levels of immunoglobulin G anti-HCV in past resolved infections than in either new infections or chronic infections. 相似文献
85.
Cara E. Rice Sara A. Vasilenko Stephanie T. Lanza John A. Davis Karen S. Fields Melissa Ervin 《Substance use & misuse》2018,53(5):852-858
Background: Men who have sex with men (MSM) have higher rates of substance use compared to men who have sex with women. Among MSM, drug use is linked to higher-risk sexual behavior and acquisition of HIV and other sexually transmitted infections. Objectives: We hypothesize that time since first acting on one's same sex attraction, or one's “gay age”, could be predictive of drug using behavior. Methods: We examined this question among 176 MSM, aged 18–35, presenting at a public sexual health clinic. Behavioral data were captured using interviewer- and self-administered surveys and clinical data were extracted from medical records. We used modified Poisson regression to examine associations between gay age and recent recreational drug use, and separately, between gay age and recent marijuana use. Results: In total, 43% of participants reported recent marijuana use and 26% of participants reported recent use of other drugs. The associations between gay age and marijuana use and other drug use varied by HIV status. After adjustment for biological age, race, and education, a one-year increase in gay age was associated with significantly increased drug use among HIV-negative men (adjusted prevalence ratio (aPR): 1.08; 95% confidence interval (CI): 1.03–1.14), but we observed no association between gay age and drug use among HIV-positive men (aPR: 0.96, 95% CI: 0.86–1.07). Gay age was not associated with marijuana use in HIV-negative (aPR: 1.00, 95% CI: 0.95–1.04) or HIV-positive (aPR: 1.06, 95% CI: 0.98–1.14) men. Conclusions: In summary, HIV-negative MSM who had experienced more time since first same-sex experience had significantly increased prevalence of recent drug use. 相似文献
86.
87.
88.
Aaron J. Fields David Rodriguez Kaitlyn N. Gary Ellen C. Liebenberg Jeffrey C. Lotz 《Journal of orthopaedic research》2014,32(2):245-252
Endplate cartilage integrity is critical to spine health and is presumably impaired by deterioration in biochemical composition. Yet, quantitative relationships between endplate biochemical composition and biomechanical properties are unavailable. Using endplate cartilage harvested from human lumbar spines (six donors, ages 51–67 years) we showed that endplate biochemical composition has a significant influence on its equilibrium tensile properties and that the presence of endplate damage associates with a diminished composition–function relationship. We found that the equilibrium tensile modulus (5.9 ± 5.7 MPa) correlated significantly with collagen content (559 ± 147 µg/mg dry weight, r2 = 0.35) and with the collagen/GAG ratio (6.0 ± 2.1, r2 = 0.58). Accounting for the damage status of the adjacent cartilage improved the latter correlation (r2 = 0.77) and indicated that samples with adjacent damage such as fissures and avulsions had a diminished modulus–collagen/GAG relationship (p = 0.02). Quasi‐linear viscoelastic relaxation properties (C, τ1, and τ2) did not correlate with biochemical composition. We conclude that reduced matrix quantity decreases the equilibrium tensile modulus of human endplate cartilage and that characteristics of biochemical composition that are independent of matrix quantity, that is, characteristics related to matrix quality, may also be important. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:245–252, 2014. 相似文献
89.
Charlotte M. Heidsma Diamantis I. Tsilimigras Susan van Dieren Flavio Rocha Daniel E. Abbott Ryan Fields Paula M. Smith George A. Poultsides Cliff Cho Mary Dillhoff Alexandra G. Lopez-Aguiar Zaheer Kanji Alexander Fisher Bradley A. Krasnick Kamran Idrees Eleftherios Makris Megan Beems Casper H.J. van Eijck Timothy M. Pawlik 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2021,23(3):413-421
BackgroundPancreatoduodenectomy (PD) or distal pancreatectomy (DP) are common procedures for patients with a pancreatic neuroendocrine tumor (pNET). Nevertheless, certain patients may benefit from a pancreas-preserving resection such as enucleation (EN). The aim of this study was to define the indications and differences in long-term outcomes among patients undergoing EN and PD/DP.MethodsPatients undergoing resection of a pNET between 1992 and 2016 were identified. Indications and outcomes were evaluated, and propensity score matching (PSM) analysis was performed to compare long-term outcomes between patients who underwent EN versus PD/DP.ResultsAmong 1034 patients, 143 (13.8%) underwent EN, 304 (29.4%) PD, and 587 (56.8%) DP. Indications for EN were small size (1.5 cm, IQR:1.0–1.9), functional tumors (58.0%) that were mainly insulinomas (51.7%). After PSM (n = 109 per group), incidence of postoperative pancreatic fistula (POPF) grade B/C was higher after EN (24.5%) compared with PD/DP (14.0%) (p = 0.049). Median recurrence-free survival (RFS) was comparable among patients who underwent EN (47 months, 95% CI:23–71) versus PD/DP (37 months, 95% CI: 33–47, p = 0.480).ConclusionComparable long-term outcomes were noted among patients who underwent EN versus PD/DP for pNET. The incidence of clinically significant POPF was higher after EN. 相似文献
90.
B E Sobel J E Saffitz L E Fields D W Myears S J Sarnoff A K Robison D A Owensby K A Fox 《Circulation》1987,75(6):1261-1272
To determine whether sustained plasma concentration of human tissue-type plasminogen activator (t-PA) can be induced promptly after intramuscular injection with enhancers of absorption devoid of deleterious local and systemic effects, we studied 250 rabbits and 13 dogs. In rabbits with t-PA injected directly into exposed muscle followed by local electrical stimulation at the site, early absorption was increased markedly by addition of 0.63M methylamine plus 0.079M hydroxylamine to the excipient. Elevations peaked within 5 min and increased with dose of t-PA, concentration of methylamine, and volume of injection medium. The enhancers were effective with percutaneous injections in the absence of local electrical stimulation as well. They did not elicit any obviously deleterious local or systemic effects. In separate experiments in rats, intramuscular injections of 0.63M methylamine plus 0.079M hydroxylamine induced local egress of intravascular radiolabeled albumin within the injection site and endothelial gaps in venules detected with colloidal carbon--changes consistent with direct effects on vascular permeability. In dogs, percutaneous intramuscular injection of t-PA in excipient without enhancers did not lead to early elevations of human t-PA in plasma, although late elevations were seen. When the enhancers were used, early elevations occurred as well, with functional activity documented by fibrin plate assays of serially obtained plasma samples and by sequential coronary angiography delineating thrombolysis after experimentally induced coronary thrombosis. The results indicate that intramuscular administration of t-PA with selected enhancers of absorption is a feasible approach for rapid induction of fibrinolysis. 相似文献