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991.
A Raisaro V Caizzi G Roda G Minzioni G Bargiggia C Bertucci F Recusani L Tronconi 《Giornale italiano di cardiologia》1988,18(3):206-212
Doppler characteristics of normally functioning tilting disk prostheses in aortic position were studied in 55 patients (30 Medtronic-Hall and 25 Sorin) whose valvular function was considered normal using clinical and echocardiographic evaluation. Peak gradients, mean gradients and effective orifice area were estimated for different sizes of prostheses. The peak gradient calculated from maximal aortic velocity was 27.3 +/- 11.1 mmHg in Sorin and 21.1 +/- 9.7 mmHg in Medtronic-Hall valves; the mean gradients were 12.9 +/- 6.2 mmHg and 10.8 +/- 5.7 mmHg in Sorin and Medtronic-Hall valves respectively. The effective orifice area calculated by the continuity equation was 1.4 +/- 0.5 cm2 in Sorin and 1.5 +/- 0.57 cm2 in Medtronic-Hall prostheses; the performance index calculated as the ratio between functional area and manufactured area was 0.4-0.6 for Medtronic-Hall and 0.45-0.52 for Sorin prostheses. Prosthetic regurgitation was found in 64% of Sorin valves and 80% of Medtronic-Hall valves; prosthetic regurgitation was mild in 81% and moderate in 19% of cases. Doppler echocardiography is a reliable method for the characterization of the normal function of prosthetic aortic valves and provides information similar to cardiac catheterization. 相似文献
992.
Controlled insect-sting challenge in 55 patients: correlation between activation of plasminogen and the development of anaphylactic shock 总被引:1,自引:0,他引:1
van der Linden PW; Hack CE; Struyvenberg A; Roem D; Brouwer MC; de Boer JP; van der Zwan JK 《Blood》1993,82(6):1740-1748
The pathogenesis of anaphylactic shock is not completely understood. Mast cell degranulation products may stimulate endothelial cells, leading to activation of fibrinolytic and coagulation systems. We investigated the activation of these systems in insect-sting anaphylaxis. Fifty-five patients with a previous insect-sting anaphylactic reaction and 8 volunteers were challenged with an in- hospital sting. Plasma levels of von Willebrand factor (vWF), coagulation, and fibrinolytic parameters were assessed. After the sting challenge, 20 patients developed anaphylactic symptoms, 7 of whom developed hypotension. In only these 7 patients, but not in the volunteers or in the other patients with no or mild anaphylactic symptoms, vWF levels increased from 107% +/- 33% (mean +/- SD) before, to 235% +/- 134% 60 minutes after the onset of clinical symptoms. This increase of vWF was accompanied by an increase of circulating tissue- type plasminogen-activator (tPA) levels from 5 +/- 3 micrograms/L to 50 +/- 59 micrograms/L and of plasminogen-alpha 2-antiplasmin complex (PAP- c) levels from 6 +/- 3 nmol/L to 297 +/- 225 nmol/L. Both tPA and PAP-c levels peaked 5 minutes after the onset of clinical symptoms. Such increases of tPA and PAP-c were not observed in the volunteers or in the patients who did not develop shock. The increase of tPA and PAP-c levels in the hypotensive patients correlated positively with the degree of mast cell degranulation and inversely with the mean arterial pressure. We conclude that activation of plasminogen may be involved in the pathogenesis of anaphylactic shock induced by insect venom. 相似文献
993.
C. R. Valeri LCDR MC USNR With the technical assistance of W. M. Booth S. A. Gildea L. E. McCallum 《Transfusion》1968,8(4):210-219
Chromium labelling characteristics of both ACD-stored and previously frozen red cells were evaluated. The chromium uptake of previously frozen red cells processed by agglomeration was inversely related to the hemoglobin level of the suspending fluid. Ascorbic acid was not needed for the labelling of previously frozen, agglomerated red cells.
Cellular injury, as measured by increase in supernatant hemoglobin during post-thaw storage at 4 C, occurred with the agglomerated, previously frozen red cells when: (1) Na2 EDTA was present in the glycerolizing solution; (2) the disaggregation of the agglomerated red cell mass was carried out with 75 rather than 250 ml of isotonic saline; and (3) the storage temperature of the glycerolized red cells was interrupted for one week with a storage interim at either 4 C or −20 C.
By use of a phthalate ester technic, red cells were separated into three fractions on the basis of cellular density. Preferential chromium labelling of red cells was noted: the lightest fraction contained significantly more radioactivity than the heaviest fraction. 相似文献
Cellular injury, as measured by increase in supernatant hemoglobin during post-thaw storage at 4 C, occurred with the agglomerated, previously frozen red cells when: (1) Na
By use of a phthalate ester technic, red cells were separated into three fractions on the basis of cellular density. Preferential chromium labelling of red cells was noted: the lightest fraction contained significantly more radioactivity than the heaviest fraction. 相似文献
994.
Background and purpose Rapid recovery protocols after total hip arthroplasty (THA) have been introduced worldwide in the last few years and they have reduced the length of hospital stay. We show the results of the introduction of a rapid recovery protocol for primary THA for unselected patients in our large teaching hospital. Patients and methods In a retrospective cohort study, we included all 1,180 patients who underwent a primary THA between July 1, 2008 and June 30, 2012. These patients were divided into 3 groups: patients operated before, during, and after the introduction of the rapid recovery protocol. There were no exclusion criteria. All complications, re-admissions, and reoperations were registered and analyzed. Results The mean length of hospital stay decreased from 4.6 to 2.9 nights after the introduction of the rapid recovery protocol. There were no statistically significant differences in the rate of complications, re-admissions, or reoperations between the 3 groups. Interpretation In a large teaching hospital, the length of hospital stay decreased after introduction of our protocol for rapid recovery after THA in unselected patients, without any increase in complications, re-admissions, or reoperation rate. 相似文献
995.
C Torti M Zazzi L Abenavoli F Trapasso F Cesario D Corigliano L Cosco C Costa RL Curia M De Rosa G Foti C Giraldi R Leone MC Liberto D Lucchino N Marascio R Masciari G Matera V Pisani N Serrao L Surace E Zicca F Castelli M Ciccozzi M Puoti A Focà SINERGIE Study Group 《BMC infectious diseases》2012,12(Z2):S9
The SINERGIE (South Italian Network for Rational Guidelines and International Epidemiology) project is intended to set up a collaborative network comprising virologists, clinicians and public health officials dealing with patients affected by HCV disease in the Calabria Region. A prospective observational data-base of HCV infection will be developed and used for studies on HCV natural history, response to treatment, pharmaco-economics, disease complications, and HCV epidemiology (including phylogenetic analysis). With this approach, we aim at improving the identification and care of patients, focusing on upcoming research questions. The final objective is to assist in improving care delivery and inform Public Health Authorities on how to optimize resource allocation in this area. 相似文献
996.
Spatial Heterogeneity in the Response of the Proximal Femur to Two Lower‐Body Resistance Exercise Regimens
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Thomas F Lang Isra H Saeed Timothy Streeper Julio Carballido‐Gamio Roy J Harnish Lynda A Frassetto Stuart MC Lee Jean D Sibonga Joyce H Keyak Barry A Spiering Carlos M Grodsinsky Jacob J Bloomberg Peter R Cavanagh 《Journal of bone and mineral research》2014,29(6):1337-1345
Understanding the skeletal effects of resistance exercise involves delineating the spatially heterogeneous response of bone to load distributions from different muscle contractions. Bone mineral density (BMD) analyses may obscure these patterns by averaging data from tissues with variable mechanoresponse. To assess the proximal femoral response to resistance exercise, we acquired pretraining and posttraining quantitative computed tomography (QCT) images in 22 subjects (25–55 years, 9 males, 13 females) performing two resistance exercises for 16 weeks. One group (SQDL, n = 7) performed 4 sets each of squats and deadlifts, a second group (ABADD, n = 8) performed 4 sets each of standing hip abductions and adductions, and a third group (COMBO, n = 7) performed two sets each of squat/deadlift and abduction/adduction exercise. Subjects exercised three times weekly, and the load was adjusted each session to maximum effort. We used voxel‐based morphometry (VBM) to visualize BMD distributions. Hip strength computations used finite element modeling (FEM) with stance and fall loading conditions. We used QCT analysis for cortical and trabecular BMD, and cortical tissue volume. For muscle size and density, we analyzed the cross‐sectional area (CSA) and mean Hounsfield unit (HU) in the hip extensor, flexor, abductor, and adductor muscle groups. Whereas SQDL increased vertebral BMD, femoral neck cortical BMD and volume, and stance hip strength, ABADD increased trochanteric cortical volume. The COMBO group showed no changes in any parameter. VBM showed different effects of ABADD and SQDL exercise, with the former causing focal changes of trochanteric cortical bone, and the latter showing diffuse changes in the femoral neck and head. ABADD exercise increased adductor CSA and HU, whereas SQDL exercise increased the hip extensor CSA and HU. In conclusion, we observed different proximal femoral bone and muscle tissue responses to SQDL and ABADD exercise. This study supports VBM and volumetric QCT (vQCT) to quantify the spatially heterogeneous effects of types of muscle contractions on bone. © 2014 American Society for Bone and Mineral Research. 相似文献
997.
Stephanie?MC?AmentEmail author Freek?Gillissen José?MC?Maessen Carmen?D?Dirksen Maarten?F?von Meyenfeldt Trudy?van der Weijden 《BMC health services research》2014,14(1):641
Background
A quality improvement collaborative is an intensive project involving a combination of implementation strategies applied in a limited “breakthrough” time window. After an implementation project, it is generally difficult to sustain its success. In the current study, sustainability was described as maintaining an implemented innovation and its benefits over a longer period of time after the implementation project has ended. The aim of the study was to explore potentially promising strategies for sustaining the Enhanced Recovery After Surgery (ERAS) programme in colonic surgery as perceived by professionals, three to six years after the hospital had successfully finished a quality improvement collaborative.Methods
A qualitative case study was performed to identify promising strategies to sustain key outcome variables related to the ERAS programme in terms of adherence, time needed for functional recovery and hospital length of stay (LOS), as achieved immediately after implementation. Ten hospitals were selected which had successfully implemented the ERAS programme in colonic surgery (2006–2009), with success defined as a median LOS of 6 days or less and protocol adherence rates above 70%. Fourteen semi-structured interviews were held with eighteen key participants of the care process three to six years after implementation, starting with the project leader in every hospital. The interviews started by confronting them with the level of sustained implementation results. A direct content analysis with an inductive coding approach was used to identify promising strategies. The mean duration of the interviews was 37 minutes (min 26 minutes – max 51 minutes).Results
The current study revealed strategies targeting professionals and the organisation. They comprised internal audit and feedback on outcomes, small-scale educational booster meetings, reminders, changing the physical structure of the organisation, changing the care process, making work agreements and delegating responsibility, and involving a coordinator. A multifaceted self-driven promising strategy was applied in most hospitals, and in most hospitals promising strategies were suggested to sustain the ERAS programme.Conclusions
Joining a quality improvement collaborative may not be enough to achieve long-term normalisation of transformed care, and additional investments may be needed. The findings suggest that certain post-implementation strategies are valuable in sustaining implementation successes achieved after joining a quality improvement collaborative.998.
Depression leads to a poorer quality of life (QOL) which is a determinant of healthy ageing. Cost-effective solutions for enhancing QOL in the older population are much needed in China, with its rapidly ageing population. We conducted a randomized controlled trial involving 112 community-dwelling older participants with mild to moderate depression, to evaluate the effect of Tai Chi with music on QOL (57 in intervention group, 55 in control group). WHO Quality of Life-BREF was used to measure QOL at baseline and at every month for three months. Following the adjustments for sociodemographic data, the effect of intervention on QOL was assured (F = 25.145, P < 0.001, ηp2= 0.435, F = 18.696, P < 0.001, ηp2= 0.364, F = 17.473, P< 0.001, ηp2= 0.348, and F = 29.576, P < 0.001, ηp2= 0.475 for physical, psychological, social, and environment domains respectively). This intervention represents an economically viable solution to better QOL and healthy ageing in a highly populous developing nation. 相似文献
999.
1000.
Davis MC 《中国医药工业杂志》2009,40(4)
1,3,5-苯三甲酰氯和叠氮化钠在水和1,2.二氯乙烷中反应生成的苯三甲酰叠氮不予分离,一锅制备得到1,3,5.三异氰酸基苯,收率97%。操作安全。进而制备三氨基苯等衍生物。 相似文献