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991.
David C. Wolford Charles M.T. Jost Ernest C. Madu K. B. Ramanathan William Walker 《Clinical cardiology》1997,20(6):573-575
Transthoracic echocardiography (TTE) has substantial limitations for the study of abnormalities of the coronary tree. Transesophageal echocardiography (TEE) allows a more complete examination of the coronary arteries, particularly the proximal segments. This report describes the use of TEE after cardiac catheterization in the clinical management of a patient with unstable angina. While angiography first showed the giant aneurysm of the left circumflex coronary artery, TEE, by revealing an active thrombus of the lumen, prompted an immediate surgical resolution. 相似文献
992.
993.
CD4 coating, but not CD4 depletion, is a predictor of efficacy with primatized monoclonal anti-CD4 treatment of active rheumatoid arthritis 总被引:1,自引:0,他引:1
Mason U Aldrich J Breedveld F Davis CB Elliott M Jackson M Jorgensen C Keystone E Levy R Tesser J Totoritis M Truneh A Weisman M Wiesenhutter C Yocum D Zhu J 《The Journal of rheumatology》2002,29(2):220-229
OBJECTIVE: Double blind studies were conducted with the anti-CD4 monoclonal antibody (Mab) keliximab in patients with active, stable rheumatoid arthritis (RA), to confirm preliminary evidence of efficacy and safety from open. uncontrolled studies. METHODS: We enrolled 136 and 186 patients into 2 consecutive, randomized, double blind trials, with similar populations [apart from inclusion of disease modifying antirheumatic drug (DMARD)-na?ve patients in Study 2]. Patients received 4 weeks intravenous placebo or keliximab [40, 80, 120, or 140 mg twice weekly (bw), or 240 mg once weekly (ow)].The primary endpoint was the American College of Rheumatology (ACR) 20 response criteria, one week after the end of treatment. RESULTS: ACR 20 response rates in Study I were 19%, 42%, 51%*, and 69%* (*p < 0.05 compared to placebo), with placebo, 40, 80, or 140 mg keliximab bw, respectively. The response rates in Study 2 were 30%, 39%, 46% and 47% with placebo, 80 or 120 mg bw, or 240 mg keliximab ow, respectively. In the 2 studies, there was a dose dependent increase in peripheral blood CD4+ T cell coating with keliximab, but a different pattern of CD4 depletion was seen. While only 12% of keliximab treated patients in Study I had CD4 counts below 250 cells/mm3 at the end of the treatment period, 47% fell below this level in Study 2. Clinical response was not correlated with CD4 depletion, but was correlated with CD4+ T cell coating with keliximab. CONCLUSION: Coating of peripheral blood CD4+ T cells with keliximab, but not CD4 depletion, is a determinant of clinical response. 相似文献
994.
Tan LH Spinks JA Eden GF Perfetti CA Siok WT 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(24):8781-8785
Language development entails four fundamental and interactive abilities: listening, speaking, reading, and writing. Over the past four decades, a large body of evidence has indicated that reading acquisition is strongly associated with a child's listening skills, particularly the child's sensitivity to phonological structures of spoken language. Furthermore, it has been hypothesized that the close relationship between reading and listening is manifested universally across languages and that behavioral remediation using strategies addressing phonological awareness alleviates reading difficulties in dyslexics. The prevailing view of the central role of phonological awareness in reading development is largely based on studies using Western (alphabetic) languages, which are based on phonology. The Chinese language provides a unique medium for testing this notion, because logographic characters in Chinese are based on meaning rather than phonology. Here we show that the ability to read Chinese is strongly related to a child's writing skills and that the relationship between phonological awareness and Chinese reading is much weaker than that in reports regarding alphabetic languages. We propose that the role of logograph writing in reading development is mediated by two possibly interacting mechanisms. The first is orthographic awareness, which facilitates the development of coherent, effective links among visual symbols, phonology, and semantics; the second involves the establishment of motor programs that lead to the formation of long-term motor memories of Chinese characters. These findings yield a unique insight into how cognitive systems responsible for reading development and reading disability interact, and they challenge the prominent phonological awareness view. 相似文献
995.
Hauer KE Wachter RM McCulloch CE Woo GA Auerbach AD 《Archives of internal medicine》2004,164(17):1866-1871
BACKGROUND: Hospitalists are increasingly serving as inpatient attendings at teaching hospitals. The educational impact of this new model is unclear. We evaluated the relationship between type of attending (hospitalist vs traditional) and trainees' ratings of attending teaching and the overall ward rotation. METHODS: We analyzed data from a Web-based evaluation system containing all house staff and student evaluations of their attendings and internal medicine ward rotations at 2 university-affiliated teaching hospitals over a 2-year period (1999-2001). RESULTS: The overall evaluation completion rate was 91% (1587 of 1742 evaluations) by trainees working with 17 hospitalists and 52 traditional attendings. Trainees reported significantly more overall satisfaction with hospitalists than traditional attendings (8.3 vs 8.0 on a 9-point scale; P<.001) and rated hospitalists' overall teaching effectiveness as superior (4.8 vs 4.5 on a 5-point scale; P<.001). Perceived overall educational value of rotations was higher with hospitalist attendings (3.9 vs 3.7 on a 5-point scale; P =.04). Trainees evaluated hospitalists' knowledge, teaching, and feedback as superior to that of traditional attendings. There were no significant differences in reports of attendings' interest in teaching or patients, availability, or emphasis on cost-effectiveness. CONCLUSIONS: Trainees reported more effective teaching and more satisfying inpatient rotations when supervised by hospitalists. This analysis suggests that hospitalists may possess or accrue a specific inpatient knowledge base and teaching skill that distinguishes them from nonhospitalists. 相似文献
996.
Low isoniazid concentrations and outcome of tuberculosis treatment with once-weekly isoniazid and rifapentine 总被引:5,自引:0,他引:5
Weiner M Burman W Vernon A Benator D Peloquin CA Khan A Weis S King B Shah N Hodge T;Tuberculosis Trials Consortium 《American journal of respiratory and critical care medicine》2003,167(10):1341-1347
To understand why once-weekly isoniazid/rifapentine therapy for tuberculosis was less effective than twice-weekly isoniazid/rifampin, we studied human immunodeficiency virus-seronegative patients with either failure (n = 4), relapse (n = 35), or cure (n = 94), recruited from a comparative treatment trial. In multivariate analyses that were adjusted for severity of disease, low plasma concentrations of isoniazid were associated with failure/relapse with once-weekly isoniazid/rifapentine (median isoniazid area under the concentration-time curve for 12 hours after the dose [AUC(0-12)] was 36 microg x hour/ml in failure/relapse versus 56 microg x hour/ml in control cases p = 0.005), but not with twice-weekly isoniazid/rifampin. Furthermore, two patients who relapsed with Mycobacterium tuberculosis monoresistant to rifamycin had very low concentrations of isoniazid. Finally, isoniazid acetylator status determined by N-acetyltransferase type 2 genotype was associated with outcome with once-weekly isoniazid/rifapentine (p = 0.03) but not twice-weekly isoniazid/rifampin. No rifamycin pharmacokinetic parameter was consistently and significantly associated with outcome (p > 0.10). Because low isoniazid concentrations were associated with failure/relapse, a drug with consistently greater area under the concentration-time curve than isoniazid may be needed to achieve highly active once-weekly therapy with rifapentine. 相似文献
997.
Voronov E Shouval DS Krelin Y Cagnano E Benharroch D Iwakura Y Dinarello CA Apte RN 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(5):2645-2650
Here, we describe that microenvironmental IL-1 beta and, to a lesser extent, IL-1 alpha are required for in vivo angiogenesis and invasiveness of different tumor cells. In IL-1 beta knockout (KO) mice, local tumor or lung metastases of B16 melanoma cells were not observed compared with WT mice. Angiogenesis was assessed by the recruitment of blood vessel networks into Matrigel plugs containing B16 melanoma cells; vascularization of the plugs was present in WT mice, but was absent in IL-1 beta KO mice. The addition of exogenous IL-1 into B16-containing Matrigel plugs in IL-1 beta KO mice partially restored the angiogenic response. Moreover, the incorporation of IL-1 receptor antagonist to B16-containing plugs in WT mice inhibited the ingrowth of blood vessel networks into Matrigel plugs. In IL-1 alpha KO mice, local tumor development and induction of an angiogenic response in Matrigel plugs was less pronounced than in WT mice, but significantly higher than in IL-1 beta KO mice. These effects of host-derived IL-1 alpha and IL-1 beta were not restricted to the melanoma model, but were also observed in DA/3 mammary and prostate cancer cell models. In addition to the in vivo findings, IL-1 contributed to the production of vascular endothelial cell growth factor and tumor necrosis factor in cocultures of peritoneal macrophages and tumor cells. Host-derived IL-1 seems to control tumor angiogenesis and invasiveness. Furthermore, the anti-angiogenic effects of IL-1 receptor antagonist, shown here, suggest a possible therapeutic role in cancer, in addition to its current use in rheumatoid arthritis. 相似文献
998.
STUDY OBJECTIVES: To assess the effect of megestrol acetate (MA), a progestational appetite stimulant commonly used in patients with AIDS and cancer, on body weight and composition, respiratory muscle strength, arterial blood gas levels, and subjective perceptions in COPD patients. DESIGN AND SETTING: Prospective, double-blind, randomized, placebo-controlled trial conducted on an outpatient basis at 18 sites. PATIENTS: Underweight (< 95% ideal body weight) COPD patients > or = 40 years old. INTERVENTIONS: Either MA, 800 mg/d oral suspension, or placebo at a 1:1 ratio for 8 weeks. RESULTS: Of 145 randomized patients (63% men), 128 patients completed the trial. Body weight increased by 3.2 kg in the MA group and 0.7 kg in the placebo group (p < 0.001). Anthropometric and dual-energy radiograph absorptiometry assessments confirmed that weight gain was mainly fat. Spirometry and maximal voluntary ventilation showed no significant changes from baseline in either group, and the difference in the change in maximum inspiratory pressure between groups was not significant. The 6-min walk distances did not differ statistically between groups at week 2 and week 4, but were greater in the placebo group at week 8 (p = 0.012). Consistent with the known ability of MA to stimulate ventilation, PaCO(2) decreased (4.6 mm Hg, p < 0.001) and PaO(2) increased (2.8 mm Hg, p < 0.04) in the MA group. Questionnaires revealed that body image and appetite improved in the MA group but not the placebo group. Adverse event frequency and type were similar in both groups, but cortisol and testosterone (in men) levels decreased substantially in the MA group. CONCLUSIONS: We conclude that MA safely increased appetite and body weight, stimulated ventilation, and improved body image in underweight COPD patients, but did not improve respiratory muscle function or exercise tolerance. 相似文献
999.
Improved patient survival after acute variceal bleeding: a multicenter,cohort study 总被引:12,自引:0,他引:12
Chalasani N Kahi C Francois F Pinto A Marathe A Bini EJ Pandya P Sitaraman S Shen J 《The American journal of gastroenterology》2003,98(3):653-659
OBJECTIVE: Existing literature indicates that the mortality rate with each variceal bleeding episode is 30-50%. Over the past 2 decades, there have been significant developments in the management of variceal bleeding. The effect of these developments on the natural history of variceal bleeding is unclear. Therefore, a retrospective, multicenter study was conducted to define the outcomes of variceal bleeding and to describe the patterns of current practice in the management of variceal bleeding. METHODS: All patients with documented variceal bleeding hospitalized at four large county hospitals from January 1, 1997, to June 30, 2000, were included. Study outcomes were in-hospital, 6-wk, and overall mortality, rate of rebleeding, transfusion requirement, and length of stay. After discharge, patients were followed until death or study closure date, on June 30, 2000. RESULTS: A total of 231 subjects were included, and their in-hospital, 6-wk, and overall mortality rates were 14.2%, 17.5%, and 33.5%, respectively. The frequency of rebleeding during follow-up was 29%. Median length of total hospital stay was 8 days (0-34 days). Median number of packed red cell units transfused was 4 U (0-60 U). Upper endoscopy was performed in 95% of patients within 24 h, and endoscopic therapy was done in all but eight patients (ligation 64%, sclerotherapy 33%). Octreotide was administered in 74% of the patients. Portasystemic shunts were performed in 7.5% of the patients for controlling acute variceal bleeding. CONCLUSIONS: The mortality rate after variceal bleeding in this study was substantially lower than previously reported. This suggests that advances made in the management of variceal bleeding have improved outcomes after variceal bleeding. 相似文献
1000.