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排序方式: 共有1610条查询结果,搜索用时 31 毫秒
1.
OBJECTIVE: To determine the most frequent clinical causes of a prolonged activated partial thromboplastin time (APTT) result, and to determine whether a new heparin-removal device (the Hepchek, Pall Biomedical, Glen Cove, NY 11542) is capable of efficiently detecting the causes of these values. DESIGN: A combination of chart review and laboratory testing comparing the criterion standard--the heparin chromogenic substrate assay--with the Hepchek. Laboratory investigations were blinded and controlled. SETTING: Inpatient, acute-care hospital. PATIENTS: A total of 1,000 hospital patients with a variety of hemostatic disorders. MAIN OUTCOME MEASURE: The extent to which the Hepchek accurately identified the etiology of a prolonged APTT result. RESULTS: The APTT was prolonged in 25.2% of samples. The presence of heparin in the sample was confirmed by chromogenic assay or by using the Hepchek heparin-removal filter. The presence of heparin was confirmed in 12.8% of all samples and in more than 50% of all abnormal samples. The cause of the abnormal APTT was often unappreciated by the clinician. Bayesian analysis of the Hepchek's ability to diagnose heparin correctly as the cause of the abnormal APTT showed a sensitivity of 100% and specificity of 99.9%. CONCLUSION: Use of the Hepchek in the routine clinical laboratory is an efficient and rapid method of detecting heparin as a cause of isolated prolonged APTT results, and should reduce demands for unwarranted coagulation analyses and inappropriate treatment with blood products. 相似文献
2.
Coronary artery bypass grafts: visualization with MR imaging 总被引:1,自引:0,他引:1
3.
Uta Kraus-Tiefenbacher Lelia Bauer Antonella Scheda Carola Schoeber Joerg Schaefer Volker Steil Frederik Wenz 《BMC cancer》2007,7(1):178
Background
For patients suffering of recurrent breast cancer within the irradiated breast, generally mastectomy is recommended. The normal tissue tolerance does not permit a second full-dose course of radiotherapy to the entire breast after a second breast-conserving surgery (BCS). A novel option is to treat these patients with partial breast irradiation (PBI). This approach is based on the hypothesis that re-irradiation of a limited volume will be effective and result in an acceptable frequency of side effects. The following report presents a single center experience with intraoperative radiotherapy (IORT) during excision of recurrent breast cancer in the previously irradiated breast. 相似文献4.
Ronald J. Hogg Fred G. Silva Philip L. Berry James E. Wenz 《Pediatric nephrology (Berlin, Germany)》1993,7(1):27-31
We report clinical and pathological data in 56 adolescents presenting with gross hematuria (GH) and 65 presenting with idiopathic nephrotic syndrome (INS). IgA nephropathy (present in 52%) and other mesangial lesions were found in the majority of the 56 patients with GH. Many of these patients had complex urological procedures prior to consideration of a nephrological problem. This often led to significant delays in making the appropriate diagnosis. Pathological lesions in the 65 patients with INS included minimal change NS (MCNS) in 31%, membranous glomerulonephritis (MGN) and focal segmental glomerulosclerosis (FSGS) in 18.5% each, and membranoproliferative GN (MPGN) in 12%. In 47 of the patients with INS, in whom no specific treatment had been given prior to renal biopsy, MCNS and MGN were observed with a similar frequency (26% and 23%, respectively), with FSGS and MPGN being found in 21% and 11%. These results indicate that the pathological lesions in adolescents with INS who undergo a renal biopsy more closely resemble those in adults, and are usually more severe than those in young children. However, it should be noted that our study was retrospective. Hence, there were probably some adolescents with INS who had a successful response to therapy and therefore did not have a renal biopsy performed.
Southwest Pediatric Nephrology Study Group (Central Office, Baylor University Medical Center at Dallas, Tex., USA). Director, Ronald J. Hogg; Associate Directors, Fred G. Silva and F. Bruder Stapleton; Statistician, Joan S. Reisch; Administrative Assistant, Kaye Green. Participating Centers—Baylor College of Medicine, Houston, Tex.: Phillip L. Berry, L. Leighton Hill, Sami A, Sanjad, Edith Hawkins; Baylor University Medical Center, Dallas, Tex.: Ronald J. Hogg, Kaye Green; Tulane University Medical Center, New Orleans, La.: Frank Boineau, John E. Lewy, Radhakrishna Baliga, Patrick Walker; University of Arkansas, Little Rock, Ark.: Watson Arnold, Eileen Ellis, Edward Uthman; University of Colorado Health Science Center, Denver, Colo.: Gary M. Lum, Wiliam Hammond; University of Oklahoma Medical Center, Oklahoma City, Okla.: James Wenzl, James Matson, Geoffrey Altshuler, Sarah Johnson; University of Tennessee, Memphis, Tenn.: F. Bruder Stapleton, Shane Roy, III, Robert J. Wyatt, Charles McKay, William Murphy; University of Texas Health Science Center at Dallas, Tex.: Billy S. Arant Jr, Michel Baum, Fred G. Silva, Arthur Weinberg, Craig Argyle, Joseph Rutledge, Ed Eigenbrodt; University of Texas Medical School, Houston, Tex.: Susan B. Conley, Jacques Lemine, Ron Portman, Ann Ince, Regina Verani; University of Texas Health Science Center at San Antonio, Tex.: Michael Foulds, Sudesh Makker, Kanwal Kher, Melanie Sweet, Victor Saldivar, Fermin Tio; University of Texas Medical Branch, Galveston, Tex.: Ben H. Brouhard, Alok Kalia, Luther B. Travis, Lisa Hollander, Tito Cavallo, Srinivasan Rajaraman; University of Utah Medical Center, Salt Lake City; Utah: Eileen Brewer, Richard Siegler, Elizabeth Hammond, Theodore Pysher.
Note that this list reflects the investigators' addresses and positions during the period of this study and not necessarily their current situations. 相似文献
5.
6.
D. Chemla P. Démolis M. Thyrault D. Annane Y. Lecarpentier and JF Giudicelli 《Fundamental & clinical pharmacology》1996,10(4):393-399
Summary— The influence of local resistance and cardiac performance on peripheral blood acceleration was investigated in 14 healthy male volunteers. Steady and pulsatile flow was studied in the brachial and in the common carotid arteries, ie, two territories that exhibit marked differences in resistive characteristics. Instantaneous blood velocity (V), mean blood velocity (Vm ) and artery diameter (D) were evaluated at rest by an ultrasonic range-gated pulsed Doppler flowmeter using a double transducer probe, thus allowing the calculation of mean blood flow (Q). Mean local resistance (R) was obtained by dividing the mean arterial pressure by Q. The peak value of the local acceleration of the blood was obtained by computer-assisted calculation of the first derivative of instantaneous blood velocity (Gmax = +dV/dtmax ). Peak aortic blood acceleration (GAo) was simultaneously measured from the suprasternal notch using a pulsed Doppler velocity meter. In the brachial and the common carotid arteries, Gmax was of a similar magnitude (551 ±30 and 555 ± 44 cm/s2 , respectively) despite major differences in the respective D, Vm , Q and R values. In neither artery was there a relationship between Gmax and either resting Q or R. At the brachial artery level, Gmax was positively related to GAo ( r = 0.79, P = 0.0008). At the common carotid artery level, there was a weak, although non significant relationship between Gmax and GAo ( P = 0.08). Our results indicate that the local acceleration of peripheral blood flow in the brachial artery is related rather to upstream central impulse than to downstream hemodynamics, and suggest some regional differences in the hemodynamic determinants of the local acceleration of peripheral blood flow. 相似文献
7.
In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population. 相似文献
8.
9.
Chronic exposure of humans to benzene (BZ), a myelotoxin, causes aplastic anemia and acute leukemia. The stromal macrophage that produces interleukin-1 (IL-1), a cytokine essential for hematopoiesis, is a target of BZ's toxicity. Monocyte dysfunction and decreased IL-1 production have been shown to be involved in aplastic anemia in humans. Hydroquinone (HQ), a toxic bone marrow (BM) metabolite of BZ, causes time- and concentration-dependent inhibition of processing of the 34-Kd pre-interleukin-1 alpha (IL-1 alpha) to the 17-Kd mature cytokine in murine P388D1 macrophages and BM stromal macrophages, as measured by Western immunoblots of cell lysate proteins using a polyclonal rabbit antimurine IL-1 alpha antibody. HQ over a 10-fold concentration range had no effect on the lipopolysaccharide (LPS)-induced production of pre- IL-1 alpha precursor or on cell viability or DNA and protein synthesis. Stromal macrophages obtained from the femoral BM of C57Bl/6 mice exposed to BZ (600 or 800 mg/kg body weight) for 2 days were incapable of processing the 34-Kd pre-IL-1 alpha to the mature 17-Kd cytokine when stimulated in culture with LPS. Stromal macrophages from mice coadministered BZ and indomethacin, a prostaglandin H synthase (PHS) inhibitor that has been shown to prevent BZ-induced myelotoxic and genotoxic effects in mice when coadministered with benzene were able to convert the pre-IL-1 alpha to mature cytokine. Administration of recombinant murine IL-1 alpha (rMuIL-1 alpha) to mice before a dose of BZ that causes severe depression of BM cellularity completely prevents BM depression, most probably by bypassing the inability of the stromal macrophage in BZ-treated animals to process pre-IL-1 alpha to the mature cytokine. 相似文献
10.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献