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51.
52.
Jaques Bourdillon 《The Journal of experimental medicine》1939,69(6):819-831
In serum of patients with nephrosis both albumin and globulin showed by osmotic pressure nearly double the molecular weights of normal albumin and globulin. In the urines of such patients, on the other hand, both proteins showed molecular weights lower even than in normal serum. The colloidal osmotic pressures were measured by the author''s method at such dilutions that the van''t Hoff law relating pressures to molecular concentrations could be directly applied. For the albumin and globulin of normal serum the molecular weights found were 72,000 and 164,000 respectively, in agreement with the weights obtained by other methods. 相似文献
53.
Biliary tract melanoma 总被引:1,自引:0,他引:1
A case of melanoma of the upper extremity with a solitary metastasis to the common bile duct is reported. A comprehensive review of melanoma in the biliary tree is presented. Antemortem diagnoses of such cases are rare but are associated with a high percentage of disease clinically confined to the biliary tree. Patients with such lesions have survived long periods of time after palliative surgery. Therefore, surgical resection is recommended as the treatment of choice in patients able to tolerate surgery. 相似文献
54.
R.B. Martino D.R. Waisberg A.P.M. Dias V.B.S. Inoue R.M. Arantes L.B.P. Haddad V. Rocha-Santos R.S.N. Pinheiro L.S. Nacif L.A.C. DAlbuquerque 《Transplantation proceedings》2018,50(3):754-757
Background
In the Model for End-Stage Liver Disease (MELD) system, patients with “MELD exceptions” points may have unfair privilege in the competition for liver grafts. Furthermore, organ distribution following identical ABO blood types may also result in unjust organ allocation. The aim of this study was to investigate access to liver transplantation in a tertiary Brazilian center, regarding “MELD exceptions” situations and among ABO-blood groups.Methods
A total of 465 adult patients on the liver waitlist from August 2015 to August 2016 were followed up until August 2017. Patients were divided into groups according to ABO-blood type and presence of “exceptions points.”Results
No differences in outcomes were observed among ABO-blood groups. However, patients from B and AB blood types spent less time on the list than patients from A and O groups (median, 46, 176, 415, and 401 days, respectively; P = .03). “Exceptions points” were granted for 141 patients (30.1%), hepatocellular carcinoma being the most common reason (52.4%). Patients with “exceptions points” showed higher transplantation rate, lower mortality on the list, and lower delta-MELD than non-exceptions patients (56.7% vs 19.1% [P < .01]; 18.4% vs 38.5% [P < .01], and 2.0 ± 2.6 vs 6.9 ± 7.0 [P < .01], respectively). Patients with refractory ascites had a higher mortality rate than those with other “exceptions” or without (48%).Conclusions
The MELD system provides equal access to liver transplantation among ABO-blood types, despite shorter time on the waitlist for AB and B groups. The current MELD exception system provides advantages for candidates with “exception points,” resulting in superior outcomes compared with those without exceptions. 相似文献55.
L B Jaques S M Wice L M Hiebert 《The Journal of laboratory and clinical medicine》1990,115(4):422-432
Heparin and dextran sulfates 8000 are separated from citrated plasma by absorption on epichlorohydrin triethanolamine cellulose columns followed by elution with 1.1 and 1.4 mol/L NaCl in 0.05 mol/L glycine-HCl buffer. The eluate is desalted with Sephadex G25-40, dried, and dissolved in water. A 1 microliters sample is applied to an agarose gel slide. After electrophoresis, the slide is fixed and stained with toluidine blue. The sulfated polysaccharide band(s) is identified by relative electrophoretic migration. The total amount of drug is estimated by matching its optical density with that of a band on one of a set of slides with graded amounts of heparin or dextran sulfate. The reaction with toluidine blue measures the total polyelectrolyte, not just the small proportion of the drug with anticoagulant activity. Pooled normal plasma showed a trace of chondroitin and no heparin. Recovery of heparin and hydrogenated dextran sulfate that was added to pooled normal plasma was complete (lowest concentration tested was 10 micrograms/ml); however, recovery for unhydrogenated dextran sulfate declined consistently by 9 micrograms/ml for concentrations below 50 micrograms/ml, setting a limit for its recovery. Plasma samples taken from patients for coagulation tests were examined by this procedure, and in so doing, steps were ascertained to improve the procedure for routine use. Results were compared with values for prothrombin time and activated partial thromboplastin times obtained on the same samples by the clinical laboratory. Because the procedure provides an independent parameter for measurement in patients who have received heparin therapy, insight into different patient responses to the drug is therefore possible. With minor modifications, the procedure can be used for heparans, dermatans, and chondroitins, because it allows identification and microscale quantitation on the basis of charge, molecular weight, and carbohydrate structure. 相似文献
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Aspirin irreversibly inhibits platelet cyclooxygenase-1 (COX-1). Aspirin sensitivity can be measured easily by its inhibition of arachidonic acid (AA) -induced platelet aggregation. Aspirin resistance has to be defined by its inability to inhibit COX-1. By using this definition, aspirin resistance very likely does not exist. A specific rapid laboratory test using either AA-induced platelet aggregation or AA-induced malondialdehyde production in platelet-rich plasma is needed to test aspirin sensitivity. The reports on so-called aspirin resistance are usually due to noncompliance of aspirin intake or consumption of inadequate doses of aspirin. In addition, data generated from using nonspecific platelet function tests have added confusion to this observed phenomenon of aspirin resistance. 相似文献
59.
Srinivasan Rajaraman Andrei V. Gribok Nancy J. Wesensten Thomas J. Balkin Jaques Reifman 《Sleep》2009,32(10):1377-1392
We present a method based on the two-process model of sleep regulation for developing individualized biomathematical models that predict performance impairment for individuals subjected to total sleep loss. This new method advances our previous work in two important ways. First, it enables model customization to start as soon as the first performance measurement from an individual becomes available. This was achieved by optimally combining the performance information obtained from the individual''s performance measurements with a priori performance information using a Bayesian framework, while retaining the strategy of transforming the nonlinear optimization problem of finding the optimal estimates of the two-process model parameters into a series of linear optimization problems. Second, by taking advantage of the linear representation of the two-process model, this new method enables the analytical computation of statistically based measures of reliability for the model predictions in the form of prediction intervals.Two distinct data sets were used to evaluate the proposed method.Results using simulated data with superimposed white Gaussian noise showed that the new method yielded 50% to 90% improvement in parameter-estimate accuracy over the previous method. Moreover, the accuracy of the analytically computed prediction intervals was validated through Monte Carlo simulations. Results for subjects representing three sleep-loss phenotypes who participated in a laboratory study (82 h of total sleep loss) indicated that the proposed method yielded individualized predictions that were up to 43% more accurate than group-average prediction models and, on average, 10% more accurate than individualized predictions based on our previous method.
Citation:
Rajaraman S; Gribok AV; Wesensten NJ; Balkin TJ; Reifman J. An improved methodology for individualized performance prediction of sleep-deprived individuals with the two-process model. 相似文献60.
Mansfield SD Scott J Oppong K Richardson DL Sen G Jaques BC Manas DM Charnley RM 《The British journal of surgery》2008,95(12):1512-1520