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41.
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Physico-chemical and medico-biological methods, including hematology and cytology, were used in an evaluation of properties of poly(2-hydroxyethyl methacrylate) (poly(HEMA))-based embolic material indicated in the occlusion of branches of hepatic artery of patients with focal alterations of the liver. The elastographic method helped in predicting mechanical properties of the hydrogel material. Poly(HEMA) was mechanically stable for endovascular applications, exhibited no significant loss in elasticity and possessed consistency resembling the soft tissue of the organism. Analysis of blood in contact with poly(HEMA) hydrogel provided a control of its biological inertness. Recently, 315 patients with focal alterations of the liver, including hemobilic hemorrhages and both primary and metastatic tumors, underwent endovascular occlusion with poly(HEMA) emboli as a pre-surgical step or as a simple occlusive measure. Compared with a direct operation on hemangiomatous injuries in the liver without endovascular occlusion, embolization with poly(HEMA) allowed to reduce 2.5-3 times bleeding in the operational zone. At the same time, the poly(HEMA) embolic material induced activation of general hemostatic reaction in the postembolization period.  相似文献   
43.
Background: A number of different screening tests are frequently used in alcohol research, but our knowledge about the reliability of many of them is quite limited. Recently, this problem has received more attention. This article examines the test-retest reliability of one of these instruments—the Alcohol Use Disorder Identification Test (AUDIT)—in a general population sample.
Methods: A general population sample ( n = 457) was tested and, after approximately 1 month, was retested by using the AUDIT. Correlation between the two tests has been examined with the intraclass correlation coefficient and the κ coefficient in analysis of dichotomous variables. Specificity and sensitivity at a number of different cutoff scores have also been analyzed by using the first test as a criterion.
Results: On the item level, the correlations ranged between 0.6 and 0.8. The overall reliability of total AUDIT scores was 0.84. When stratified by gender, age, and consumer status, the total score reliability approximated 0.80 for all the categories except low alcohol consumers (0.51). Agreement using the recommended cutoff score of 8+ was also examined. The reliability (κ) observed in the whole sample was 0.691, which was interpreted as a substantial agreement. By this cutoff, 91% were correctly classified at retest compared with the first test. AUDIT 8+ showed higher reliability for males, young people, and moderate consumers and low reliability among low consumers. In terms of reliability, the most optimal cutoff for women turned out to be 6 or more.
Conclusions: According to these results, the test-retest reliability of AUDIT is high. The next step might be to examine to what extent the findings apply within health-care settings, which is what the test originally was designed for.  相似文献   
44.
Oxcarbazepine treatment of bipolar disorder   总被引:2,自引:0,他引:2  
OBJECTIVE: To assess the effectiveness and safety of oxcarbazepine in bipolar disorder. METHOD: A chart review of naturalistic treatment with oxcarbazepine in 42 outpatients with DSM-IV bipolar disorder (10 males, 32 females; mean +/- SD age = 33.3 +/- 12.4 years; 25 with bipolar disorder type I, 4 with bipolar disorder type II, and 13 with bipolar disorder not otherwise specified) was conducted. Patients had received oxcarbazepine monotherapy or adjunctive therapy between April 2000 and April 2002. Treatment response was defined as a Clinical Global Impressions-Improvement scale score of 1 (marked improvement) or 2 (moderate improvement). RESULTS: Oxcarbazepine was moderately to markedly effective in 24 subjects (57%). Mixed symptoms were the most common indication (52% [22/42]). The mean oxcarbazepine dose was 1056.6 mg/day, and mean treatment duration was 16.2 weeks. Sedation (17/42, 40%) was the most common side effect, but 16 patients (38%) had no side effects. Twenty-two patients (52%) stopped treatment, mostly due to side effects (12/22). Males were more likely to respond than females (10/10 vs. 14/32, p =.006). Dose, bipolar subtype, indication, past nonresponse to mood stabilizers, concurrent mood stabilizer use, and monotherapy use of oxcarbazepine did not differentially predict response. CONCLUSION: Oxcarbazepine appeared effective in about one half of patients with bipolar disorder and was well tolerated.  相似文献   
45.
The efficacy of candidate AIDS vaccines to mediate protection against viral infection and pathogenesis is evaluated, at a preclinical stage, in animal models. One model that is favored because the infecting virus is closely related to HIV-1 and because of the rapidity of pathogenic outcomes is the infection of Old World monkeys by simian-human immunodeficiency virus (SHIV) chimerae. We investigated the basis for the depletion of CD4(+) T lymphocytes in a SHIV-macaque model. Molecularly cloned SHIVs, SHIV-89.6 and SHIV-KB9, differ in the ability to cause CD4(+) T-cell loss at a given level of virus replication in monkeys. The envelope glycoproteins of the pathogenic SHIV-KB9 mediate membrane-fusion in cultured T lymphocytes more efficiently than the envelope glycoproteins of the non-pathogenic SHIV-89.6. The minimal envelope glycoprotein region that specifies this increase in membrane-fusing capacity was sufficient to convert SHIV-89.6 into a virus that causes profound CD4(+) T-cell depletion in monkeys. Conversely, two single amino acid changes that decrease the membrane-fusing ability of the SHIV-KB9 envelope glycoproteins also attenuated the CD4(+) T-cell destruction that accompanied a given level of virus replication in SHIV-infected monkeys. Thus, the ability of the HIV-1 envelope glycoproteins to fuse membranes, which has been implicated in the induction of viral cytopathic effects in vitro, contributes to the capacity of the pathogenic SHIV to deplete CD4(+) T lymphocytes in vivo.  相似文献   
46.
Leg complaints at maximal exercise in endurance athletes may have many causes, including arterial flow limitations in the iliac arteries. Such flow limitations can evolve into serious health problems due to increasing intravascular obstruction or even complete obstruction as a result of dissection or thrombosis. Early detection is therefore of clinical importance, but conventional diagnostic tools often prove inadequate. In the current study simple sports-specific tests are examined for their diagnostic power. Test variables derived from patient history, physical examination, cycling exercise testing followed by arterial pressure measurements at the ankle, and echo-Doppler examination with provocative manoeuvres were tested in 92 symptomatic legs (80 patients). A validated clinical classification acted as a reference. Several test variables proved useful. However, no single test variable combined a high sensitivity with a high specificity. Multivariate testing resulted in the correct classification of 91 % of patients, reaching a sensitivity of 0.90 and specificity of 0.93 (kappa 0.76). Four patients wrongly classified as non-vascular suffered from kinking in the common iliac artery that could not be visualised using the diagnostic tools currently available in this study. In conclusion: simple sports-specific tests accurately diagnose iliac artery obstruction in endurance athletes.  相似文献   
47.
The effects of different modes of prolonged exercise and different drinks on gastroesophageal reflux and reflux-related symptoms were examined. In a cross-over design seven male triathletes performed two tests at one week intervals (50 min periods of alternately running, cycling and running at 70-75% VO2max), with supplementation of either a conventional sports drink (7% carbohydrates) or tap water. Gastroesophageal reflux (percentage time and number of periods esophageal pH < 4) was measured with an ambulant pH system before, during and after exercise. Percentage reflux time (+/- SEM) during running, cycling, running and recovery was 24.0 +/- 4.6, 8.2 +/- 4.8, 17.6 +/- 8.4 and 11.8 +/- 4.0 with carbohydrates and 7.4 +/- 2.9, 0 +/- 0, 2.4 +/- 1.4 and 0.2 +/- 0.2 with water, respectively. Reflux lasted longer during exercise as compared to the rest situation (5.6 + 1.4%), especially with carbohydrates, and lasted longer with carbohydrates than with water (P < 0.05; Wilcoxon signed rank test). In general, reflux lasted longer during running than during cycling (P < 0.05). Data on the number of reflux periods are concordant to these results. Chest pain was reported by one subject during running with carbohydrates. Heartburn during running was reported by two subjects with water and by one with carbohydrates. In conclusion, physical exercise increases gastroesophageal reflux, dependent on the mode of exercise and beverage used.  相似文献   
48.
49.
Oligonucleotides containing CpG motifs (CpG ODN) are strong adjuvants for humoral immune responses but data on cellular immune responses in primates are scarce. Rhesus macaque blood contained similar numbers of plasmacytoid dendritic cells and B cells, the key sensors of CpG ODN, as human blood, and these cells were activated by CpG-A and CpG-B in vitro. In vivo, both ODNs induced equal plasma levels of interferon-inducible protein 10 and similarly enhanced antibody responses following i.m. injections of the ODNs, protein antigen, and aluminium hydroxide into rhesus macaques, whereas antigen-specific CD4(+) T cell responses were only slightly increased by CpG ODN.  相似文献   
50.
BACKGROUND: On-line hemodiafiltration (HDF) represents the supreme blood purification modality for end-stage renal disease (ESRD) patients. Large-volume infusion of on-line prepared substitution fluid may, however, expose patients to inflammatory contaminants. As a result, on-line HDF might aggravate chronic inflammation, which correlates with malnutrition, cardiovascular disease, and mortality among ESRD patients. METHODS: In a multicenter cross-over study, 27 ESRD patients were randomly assigned to treatment with on-line HDF and low-flux hemodialysis (HD). After 6 months, patients were crossed to the other treatment modality, and treatment continued for another 6 months. Both on-line HDF and low-flux HD were conducted with polysulfone membranes and ultrapure dialysis fluid. Samples were drawn at the end of each treatment period. RESULTS: Inflammatory parameters were elevated in the study population when compared to healthy controls. Induction of interleukin-1 receptor antagonist (IL-1Ra) and tumor necrosis factor alpha (TNF-alpha) was comparable for on-line HDF and low-flux HD, and there was no intradialytic increase in cytokine production. As a result, interleukin-6 (IL-6) plasma levels did not differ significantly between the two treatment modalities. Similarly, no difference between on-line HDF and low-flux HD was observed for C-reactive protein (CRP) and albumin. Markers of endothelial cell activation (soluble intercellular and vascular cell adhesion molecules sICAM-1 and sVCAM-1) as well as the cardiovascular risk marker cardiac troponin T (cTnT) remained elevated compared to healthy subjects, but showed no difference between the two treatment modalities. CONCLUSIONS: On-line HDF, as the most effective renal replacement therapy, does not provoke inflammatory response and is both safe and highly biocompatible.  相似文献   
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