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991.
Mele D Alboni P Fucà G Scarfò S Paparella N Levine RA 《Pacing and clinical electrophysiology : PACE》2000,23(12):2078-2085
During reentrant supraventricular tachycardias involving the atrioventricular node (AVN-SVT) or an AV bypass tract (AV-SVT), atrial pressure increases. While in AVN-SVT this increase relates to atrial contraction during ventricular systole, the mechanism remains unclear in AV-SVT. This study sought to clarify this mechanism. During 11 AVN-SVTs and 9 AV-SVTs, anterograde flow through the AV valves and retrograde flow in the pulmonary and hepatic veins were studied by pulsed-wave (PW) Doppler measuring the time interval between the ECG-R wave and (1) the end of venous retrograde flows, and (2) the beginning of valvular anterograde flows. The positive or negative difference between these two time intervals guided recognizing the atrial contraction against open or closed AV valves. Intracavitary pressures and cardiac index were also measured. During AVN-SVTs, venous retrograde flows always ended before the anterograde valvular flows, indicating atrial contraction against closed AV valves. During AV-SVTs, pulmonary retrograde flow ended before the beginning of mitral anterograde flow in five cases, began before but ended during the anterograde flow in three cases, and overlapped to the anterograde flow in one case. A corresponding behavior was observed at the right side of the heart. In both SVTs, atrial pressures increased and end-diastolic ventricular pressure and cardiac index decreased similarly. During AVN-SVT, the atrial contraction always occurs against closed AV valves, and during AV-SVT it generally occurs against totally or partially closed AV valves, explaining similar atrial pressure and cardiac index changes in both SVTs. 相似文献
992.
We studied correlations of pain measures in patients with either inflammatory bowel disease (IBD), a disease with a clear organic cause, or irritable bowel syndrome (IBS), a functional pain syndrome in which there is little demonstrable pathology. Correlations were determined between measures on the visual analogue scale (VAS) and on the McGill Pain Questionnaire (MPQ). The VAS score and present pain intensity scale (PPI) of the MPQ correlated well in the organic IBD but correlated poorly in the functional IBS. Differences in correlation between the VAS and PPI scores in functional versus organic disease did not appear to be due to altered sensory and affective pain components. This finding is similar to what we observed in our previous study of organic and functional pain syndromes in the musculoskeletal system. Correlations between the other measures are also discussed. 相似文献
993.
E Levine 《The American journal of nursing》1977,77(11):1799-1803
994.
Bilateral synchronous transitional ureteral carcinoma has previously been reported only 11 times. Herein, two additional cases are reported. Analysis shows these tumors to be of relatively low grade and low stage. It is necessary to fully evaluate the opposite side in a patient presenting with unilateral ureteral tumor. If bilateral disease is present, a conservative surgical procedure should be done. 相似文献
995.
Resveratrol-induced apoptotic death in human U251 glioma cells 总被引:13,自引:0,他引:13
Jiang H Zhang L Kuo J Kuo K Gautam SC Groc L Rodriguez AI Koubi D Hunter TJ Corcoran GB Seidman MD Levine RA 《Molecular cancer therapeutics》2005,4(4):554-561
Resveratrol (trans-3,4',5-trihydroxystilbene) is a naturally occurring polyphenolic compound highly enriched in grapes, peanuts, red wine, and a variety of food sources. Resveratrol has antiinflammatory and antioxidant properties, and also has potent anticancer properties. Human glioma U251 cells were used to understand the molecular mechanisms by which resveratrol acts as an anticancer agent, since glioma is a particularly difficult cancer to treat and eradicate. Our data show that resveratrol induces dose- and time-dependent death of U251 cells, as measured by lactate dehydrogenase release and internucleosomal DNA fragmentation assays. Resveratrol induces activation of caspase-3 and increases the cleavage of the downstream caspase substrate, poly(ADP-ribose) polymerase. Resveratrol-induced DNA fragmentation can be completely blocked by either a general caspase inhibitor (Z-VAD-FMK) or a selective caspase-3 inhibitor (Z-DEVD-FMK), but not by a selective caspase-1 inhibitor. Resveratrol induces cytochrome c release from mitochondria to the cytoplasm and activation of caspase-9. Resveratrol also increases expression of proapoptotic Bax and its translocation to the mitochondria. Resveratrol inhibits U251 proliferation, as measured by MTS assay [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt], and induces G0/G1 growth arrest, as determined by flow cytometry. The cyclin-dependent kinase inhibitor, olomoucine, prevents cell cycle progression and resveratrol-induced apoptosis. These results suggest that multiple signaling pathways may underlie the apoptotic death of U251 glioma induced by resveratrol, which warrants further exploration as an anticancer agent in human glioma. 相似文献
996.
A randomized controlled trial comparing the frequency of acute reactions to plasma-removed platelets and prestorage WBC-reduced platelets 总被引:4,自引:0,他引:4
Heddle NM Blajchman MA Meyer RM Lipton JH Walker IR Sher GD Constantini LA Patterson B Roberts RS Thorpe KE Levine MN 《Transfusion》2002,42(5):556-566
BACKGROUND: Removal of the plasma supernatant from platelets before transfusion is effective in preventing acute reactions to platelets caused by cytokines. Prestorage WBC reduction of platelets may be even more effective at preventing reactions as the WBCs are removed and WBC-derived cytokines do not accumulate in this component. This study evaluates the effectiveness of plasma removal and two methods of prestorage WBC reduction for preventing acute reactions to platelets. STUDY DESIGN AND METHODS: Platelets given to adults with hematologic malignancies were randomly allocated to one of three types: plasma supernatant removed and a platelet storage solution added, whole blood-derived platelets that are prestorage WBC reduced by filtration before storage, and prestorage WBC-reduced apheresis platelets. Patients were monitored before, during, and after transfusion, and the severity of reactions was graded on a Likert scale. RESULTS: A total of 129 patients from four centers were given 1190 platelet transfusions. The overall frequency of reactions was 13.6 percent (162 of 1190), 21.3 percent (36 of 169) for the plasma-removed platelets, 11.4 percent (59 of 517) for random donor WBC-reduced platelets, and 13.3 percent (67 of 504) for apheresis WBC-reduced platelets (p=0.384). The overall frequency of severe reactions was 4.1 percent with plasma-removed platelets, 1.7 percent for whole blood-derived, prestorage WBC-reduced platelets, and 1.4 percent for prestorage WBC-reduced apheresis platelets. CONCLUSION: The frequency of reactions to plasma-removed platelets and prestorage WBC-reduced platelets was not significantly different; however, the power of the study for this comparison was low. There was no difference in the frequency of reactions to the two types of prestorage WBC-reduced platelets. The frequency of severe reactions to prestorage WBC-reduced platelets is low, occurring in only 1 to 2 percent of transfusions. 相似文献
997.
998.
G. S. Lee D. S. Goldberg M. H. Levine P. L. Abt 《American journal of transplantation》2018,18(2):492-503
Organ shortage continues to challenge the field of transplantation. One potential group of donors are those who have been transplant recipients themselves, or Organ Donation After Transplant (ODAT) donors. We conducted a retrospective cohort study to describe ODAT donors and to compare outcomes of ODAT grafts versus conventional grafts. From October 1, 1987 to June 30, 2015, 517 former recipients successfully donated 803 organs for transplant. Former kidney recipients generally survived a median of approximately 4 years before becoming an ODAT donor whereas liver, lung, and heart recipients generally survived less than a month prior to donation. In the period June 1, 2005 to December 31, 2014, liver grafts from ODAT donors had a significantly higher risk of graft failure compared to non‐ODAT liver transplants (P = .008). Kidney grafts donated by ODAT donors whose initial transplant occurred >1 year prior were associated with significantly increased graft failure (P = .012). Despite increased risk of graft failure amongst certain ODAT grafts, 5‐year survival was still high. ODAT donors should be considered another form of expanded criteria donor under these circumstances. 相似文献
999.
Human leukocyte antigens antibodies after lung transplantation: Primary results of the HALT study 下载免费PDF全文
Ramsey R. Hachem Malek Kamoun Marie M. Budev Medhat Askar Vivek N. Ahya James C. Lee Deborah J. Levine Marilyn S. Pollack Gundeep S. Dhillon David Weill Kenneth B. Schechtman Lorriana E. Leard Jeffrey A. Golden LeeAnn Baxter‐Lowe Thalachallour Mohanakumar Dolly B. Tyan Roger D. Yusen 《American journal of transplantation》2018,18(9):2285-2294
Donor‐specific antibodies (DSA) to mismatched human leukocyte antigens (HLA) are associated with worse outcomes after lung transplantation. To determine the incidence and characteristics of DSA early after lung transplantation, we conducted a prospective multicenter observational study that used standardized treatment and testing protocols. Among 119 transplant recipients, 43 (36%) developed DSA: 6 (14%) developed DSA only to class I HLA, 23 (53%) developed DSA only to class II HLA, and 14 (33%) developed DSA to both class I and class II HLA. The median DSA mean fluorescence intensity (MFI) was 3197. We identified a significant association between the Lung Allocation Score and the development of DSA (HR = 1.02, 95% CI: 1.001‐1.03, P = .047) and a significant association between DSA with an MFI ≥ 3000 and acute cellular rejection (ACR) grade ≥ A2 (HR = 2.11, 95% CI: 1.04‐4.27, P = .039). However, we did not detect an association between DSA and survival. We conclude that DSA occur frequently early after lung transplantation, and most target class II HLA. DSA with an MFI ≥ 3000 have a significant association with ACR. Extended follow‐up is necessary to determine the impact of DSA on other important outcomes. 相似文献
1000.
Clinical emergence of entecavir-resistant hepatitis B virus requires additional substitutions in virus already resistant to Lamivudine 总被引:50,自引:0,他引:50 下载免费PDF全文