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排序方式: 共有2544条查询结果,搜索用时 15 毫秒
1.
Gil Bolotin Frederik H. van der Veen Roberto Lorusso Tamir Wolf Robert Sachner Rona Shofti Jan J. Shreuder Gideon Uretzky 《European journal of cardio-thoracic surgery》2002,21(6):975-980
Objective: Descending and ascending aortomyoplasty are two surgical procedures intended to induce hemodynamic benefits similar to those of the intra-aortic-balloon-pump (IABP). To date, there have been no studies comparing the two surgical techniques. The objective of this study was to compare coronary blood flow augmentation and afterload reduction as produced by descending and ascending aortomyoplasty counterpulsation Methods: Twenty-two mongrel dogs (18–35 kg) underwent IABP application (n=7), descending (n=8), or ascending (n=7) aortomyoplasty. Left anterior descending (LAD) coronary artery blood flow was measured using a Transonic Doppler flow probe. Left ventricular pressure as well as aortic pressures proximal and distal to either the aortomyoplasty site or the IABP position were monitored continuously. Results: Descending aortomyoplasty induced higher elevation in the LAD blood flow during assisted beats (27% from 10.8±4 to 13.8±6 ml/min, P<0.001) than that induced by either ascending aortomyoplasty (19% from 11.7±5 to 14±5 ml/min, P<0.001) or IABP counterpulsation (18% from 8.6±3 to 10.2±4 ml/min, P<0.001). Conversely, while ascending aortomyoplasty reduced the left ventricular end-diastolic pressure by 16% (from 60±18 to 50±22 mmHg, P<0.001), similar to the 16% after load reduction achieved by the IABP counterpulsation, descending aortomyoplasty failed to induce afterload reduction. Conclusions: Descending aortomyoplasty produces higher coronary blood flow augmentation than either ascending aortomyoplasty or IABP. However, afterload reduction comparable to that achieved by IABP was observed only with ascending aortomyoplasty and not with descending aortomyoplasty. 相似文献
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Safety of gadolinium during pregnancy 总被引:4,自引:0,他引:4
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Gideon Fait MD Dan Grisaru MD Michael Shenhav MD Michael J. Kupfermine MD Joseph B. Lessing MD M. Reuben Peyser MD Ariel Jaffa MD 《The Australian & New Zealand journal of obstetrics & gynaecology》1997,37(2):174-176
Summary: One hundred five women with a documented pregnancy of 41 weeks' gestation or more, admitted for induction of labour by balloon catheter with extra-amniotic saline instillation, were retrospectively compared to 196 women admitted in spontaneous labour at the same gestational age, with regard to mode of delivery. The success rate of the induction group was 97.1%. The mode of delivery did not differ significantly between the 2 groups. The Caesarean section rates were 11.4% in the induction group versus 9.7% in the spontaneous group. The mode of delivery after induction of labour by balloon catheter with extra-amniotic saline instillation and simultaneously commenced intravenous oxytocin infusion, in pregnancies of 41 weeks or more, is similar to that of spontaneous deliveries at the same gestational age. 相似文献
6.
W Lack R Windhager R Eyb F Meznik 《Zeitschrift für Orthop?die und ihre Grenzgebiete》1989,127(2):187-190
Total disc mobility, segmental mobility, both depending upon location of the disc and upon its position within the scoliotic curve as well as the opening angle of the disc in the ap x-ray were measured in the so-called "bending-test" x-rays of the lumbar curve of 40 patients with idiopathic scoliosis. The measurements showed a maximum of mobility in the segments L2/3, L3/4 and L4/5. In no direct dependence an increased mobility of the most proximal motion segment against the next lower one of the lumbar curve was found. No direct relation between lateral flexion and degree of scoliosis was measurable. Mobility towards the convexity increases directly with the opening angle of the disc concerned while mobility towards the concavity decreases; lateral flexion remains constant altogether. The results achieved might become quite relevant in connection with the possible therapeutic progress in the treatment of lumbar scoliosis with enzymatic dissolution of nucleus pulposus. 相似文献
7.
Mourelatos Z Dostie J Paushkin S Sharma A Charroux B Abel L Rappsilber J Mann M Dreyfuss G 《Genes & development》2002,16(6):720-728
Gemin3 is a DEAD-box RNA helicase that binds to the Survival of Motor Neurons (SMN) protein and is a component of the SMN complex, which also comprises SMN, Gemin2, Gemin4, Gemin5, and Gemin6. Reduction in SMN protein results in Spinal muscular atrophy (SMA), a common neurodegenerative disease. The SMN complex has critical functions in the assembly/restructuring of diverse ribonucleoprotein (RNP) complexes. Here we report that Gemin3 and Gemin4 are also in a separate complex that contains eIF2C2, a member of the Argonaute protein family. This novel complex is a large approximately 15S RNP that contains numerous microRNAs (miRNAs). We describe 40 miRNAs, a few of which are identical to recently described human miRNAs, a class of small endogenous RNAs. The genomic sequences predict that miRNAs are likely to be derived from larger precursors that have the capacity to form stem-loop structures. 相似文献
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A fluorescent derivative of cerebroside sulfate (12-(1-pyrene)dodecanoyl-sphingosylgalactosyl-0-3-sulfate (P12-sulfatide) has been synthesized as a potential substrate for the determination of cerebroside sulfatidase (or arylsulfatase A) activity. It was administered into cultured human skin fibroblasts and thereby utilized for the diagnosis of arylsulfatase A deficiency. Cultured skin fibroblasts from normal individuals and healthy persons suffering from a pseudoarylsulfatase A deficiency (PD) degraded the P12-sulfatide, while in cells derived from a metachromatic leukodystrophy (MLD) patient it remained essentially intact. This contrasts with in vitro determinations of enzymatic activity, where the MLD or PD-derived arylsulfatase A exhibit similar deficiency, in spite of a profoundly different clinical course. Administration of the fluorescent sulfatide into the intact cells permitted a sensitive and rapid diagnosis of MLD and its distinction from the PD-phenomenon. This might be of particular importance for cases in which a rapid diagnosis is required and for prenatal diagnosis of fetuses from families afflicted with both MLD and pseudo-deficiency mutant genes. 相似文献
10.
Factors affecting the determination of threshold doses for allergenic foods: how much is too much? 总被引:15,自引:0,他引:15
Steve L Taylor Susan L Hefle Carsten Bindslev-Jensen S Allan Bock A Wesley Burks Lynn Christie David J Hill Arne Host Jonathan O'b Hourihane Gideon Lack Dean D Metcalfe Denise Anne Moneret-Vautrin Peter A Vadas Fabienne Rance Daniel J Skrypec Thomas A Trautman Ingrid Malmheden Yman Robert S Zeiger 《The Journal of allergy and clinical immunology》2002,109(1):24-30
BACKGROUND: Ingestion of small amounts of an offending food can elicit adverse reactions in individuals with IgE-mediated food allergies. The threshold dose for provocation of such reactions is often considered to be zero. However, because of various practical limitations in food production and processing, foods may occasionally contain trace residues of the offending food. Are these very low, residual quantities hazardous to allergic consumers? How much of the offending food is too much? Very little quantitative information exists to allow any risk assessments to be conducted by the food industry. OBJECTIVE: We sought to determine whether the quality and quantity of existing clinical data on threshold doses for commonly allergenic foods were sufficient to allow consensus to be reached on establishment of threshold doses for specific foods. METHODS: In September 1999, 12 clinical allergists and other interested parties were invited to participate in a roundtable conference to share existing data on threshold doses and to discuss clinical approaches that would allow the acquisition of that information. RESULTS: Considerable data were identified in clinical files relating to the threshold doses for peanut, cows' milk, and egg; limited data were available for other foods, such as fish and mustard. CONCLUSIONS: Because these data were often obtained by means of different protocols, the estimation of a threshold dose was very difficult. Development of a standardized protocol for clinical experiments to allow determination of the threshold dose is needed. 相似文献