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排序方式: 共有813条查询结果,搜索用时 15 毫秒
61.
George Groeneweg Frank JPM Huygen Sjoerd P Niehof Feikje Wesseldijk Johannes BJ Bussmann Fabienne C Schasfoort Dirk L Stronks Freek J Zijlstra 《BMC musculoskeletal disorders》2008,9(1):143
Background
This double-blind, randomized, controlled trial investigated the effect of the phosphodiesterase-5 inhibitor tadalafil on the microcirculation in patients with cold Complex Regional Pain Syndrome (CRPS) in one lower extremity. 相似文献62.
Magnetic resonance (MR) imaging was performed on 14 patients with histologically proved osteosarcoma (mean age, 14.4 years). There was excellent correlation of intramedullary tumor extent as determined with MR imaging and pathologic examination (r = 99%). This was facilitated by the presence of a chemical shift artifact at the tumor-marrow interface on the T1-weighted images. The correlation between CT and pathologic findings was not as good (r = 84%). In a single patient, however, a 10-cm length of sclerotic bone was incorrectly interpreted as being tumor. If this case is excluded, the correlation between CT and pathologic findings improves significantly (r = 96%). T2-weighted images were optimal in demonstrating soft-tissue bulk and breach of the epiphysis or cortex. Vascular involvement was also readily defined. The T2 value of the tumor soft-tissue component decreased in patients who were deemed to have responded well to therapy. Two patients with very high T2 values after chemotherapy developed wide-spread metastatic disease and died. Phosphorus-31 MR spectroscopy of five patients with osteosarcoma showed elevated levels of phosphomonoesters (PMEs), inorganic phosphate (Pi), and phosphodiesters (PDEs). PME and PDE peak areas decreased in three patients after chemotherapy, while Pi peak areas increased. 相似文献
63.
In the past 10 years, a number of authors have expressed concern that surgeons are abdicating their traditional role of providing preoperative and postoperative care in surgical intensive care units. To study today's private practice environment, we took a survey. Questionnaires were sent to the chiefs of surgery and the nurse managers of the surgical intensive care units at 188 non-university-affiliated hospitals throughout the United States. Results show that surgeons do not have the principal managing role in the intensive care unit for surgical patients in 70% to 75% of the hospitals. Results also indicated that surgeons are relinquishing their responsibilities in the direct care of the preoperative and postoperative critically ill patients. Three main reasons are given for this: (1) an ever-increasing body of critical care knowledge plus complex technology, (2) a lack of economic incentive, and (3) professional liability. To reverse this trend, these three areas must be addressed. 相似文献
64.
Intensive weekly chemotherapy for good-prognosis patients with small-cell lung cancer. 总被引:1,自引:0,他引:1
D W Miles H M Earl R L Souhami P G Harper R Rudd C M Ash L James C W Trask J S Tobias S G Spiro 《Journal of clinical oncology》1991,9(2):280-285
A weekly, intensive chemotherapy regimen has been used to treat 70 patients with small-cell lung cancer (SCLC). Forty-five patients had limited disease (LD) and 25 extensive disease (ED) with good prognostic features. The regimen consisted of cisplatin 50 mg/m2 intravenously (IV) day 1 and etoposide 75 mg/m2 IV days 1 and 2, alternating weekly with ifosfamide 2 g/m2 IV day 8 and doxorubicin 25 mg/m2 IV day 8, for a total of 12 weeks. Dose modifications were made according to defined hematologic criteria. Responding patients with limited disease subsequently received mediastinal radiotherapy. Overall response to chemotherapy was 91% with a complete response (CR) rate of 50%. Forty-five patients with limited disease (LD) achieved an overall response rate of 91% with a CR rate of 51%, and 25 patients with extensive disease (ED) achieved an overall response rate of 92% with a CR rate of 48%. Median survival for the whole group was 54 weeks (LD, 58 weeks; ED, 42 weeks). Hematologic toxicity was predictable, without the wide fluctuations in WBC count seen in conventional 3-weekly regimens. In all, one quarter of treatment courses were delayed, most frequently because of leukopenia. Dose reductions were required in 63% of cases. The average delivered dose intensity was calculated and shown to be 73% of projected. Nonhematologic toxicity was mild with nausea and vomiting being the most common. This weekly schedule of chemotherapy has proved to be active and well tolerated and is currently being compared with conventional 3-weekly chemotherapy in a randomized study. 相似文献
65.
R. E. Coleman P. G. Harper C. Gallagher R. Osborne E. M. Rankin A. C. Silverstone M. L. Slevin R. L. Souhami J. S. Tobias C. W. Trask E. Wiltshaw 《Cancer chemotherapy and pharmacology》1986,18(3):280-283
Summary Forty-one patients with advanced progressing carcinoma of the cervix were treated with ifosfamide 1.5 g/m2 daily in a 30-min infusion for 5 days every 3 weeks. The overall response rate (complete + partial) was 12/39 (31%), or 12/30 (40%) in those who had not received previous chemotherapy. Six patients achieved a complete remission of disease and four of these remain disease-free 24–39 months later. Durable response were seen in patients with disease progressing after radical radiotherapy.Bone marrow suppression was the dose-limiting toxicity and led to dosage modification in 24 patients. Nausea and vomiting was experienced by all patients at some time during therapy and all patients developed alopecia. Mild neurological toxicity occurred in seven patients but severe life-threatening neurotoxicity was not seen with this schedule of administration.Further studies are needed to identify the optimum dose and schedule of ifosfamide and to ascertain its place in combination therapy. 相似文献
66.
67.
Andrew L. Johnson Joseph A. Jurcisek O. Joseph Trask Jessie L. -S. Au 《The AAPS journal》1999,1(2):46-52
This report describes a method for monitoring the transfer of DNA during transfection. This method involves random labeling of plasmid DNA with fluorescein-12-dUTP, flow cytometric detection and sorting of the fluorescent transfected cells, and laser confocal fluorescence microscopic determination of the intracellular location of the plasmid DNA. By this method, >95% of the sorted cells were labeled, indicating a >95% specificity of the sorting procedure. The sorted cells were viable, as indicated by their ability to exclude trypan blue dye (>98% cells excluded the dye) and to maintain cell growth. The results of the kinetics of the Lipofectin transfection technology show that the fraction of the cells that internalized plasmid DNA increased from 10% at 1 hr after initiation of the transfection procedures to 18% at 3 hr. This method does not require protein expression, does not require the use of selection pressure such as drug treatment to isolate the cells that internalized DNA, and can be used to study the early events of DNA transfection. 相似文献
68.
Role of point A in the era of computerized dosimetry 总被引:1,自引:0,他引:1
69.
L C Yao D P Humen T K Shnitka K Trask B I Jugdutt 《The Canadian journal of cardiology》1987,3(7):326-333
Technetium pyrophosphate uptake at the site of catheter shock was studied in four patients and seven experimental dogs. Technetium pyrophosphate scintigraphy was performed following five catheter ablation attempts in humans at different cardiac sites, and following 24 J catheter shocks delivered in the right and left ventricles of seven dogs. In the patients, gamma camera imaging with tomographic reconstruction showed intense focal uptake at the sites of shock. The scans were positive from 1.5 to 5.5 h following ablation and stayed positive for up to five days. In the animals, the low energy shocks produced circumscribed areas of coagulation and contraction band necrosis. The binding of technetium pyrophosphate at these sites was confirmed by in vivo gamma camera imaging, epicardial counting with a 1.2 cm scintillation probe and ex vivo imaging. Ratios of focal binding to normal myocardial uptake of technetium pyrophosphate were calculated from the digital gamma camera images. In all cases, technetium pyrophosphate was bound to myocardial sites where transcatheter energies were delivered in both humans and dogs. Intraoperative localization of the origin of tachycardia in man may be facilitated by combining preoperative endocardial catheter mapping, catheter shock, radionuclide labelling of the site of shock and a search for the focus of radionuclide concentration during subsequent surgery. 相似文献
70.
Rosebrough SF; Grossman ZD; McAfee JG; Kudryk BJ; Subramanian G; Ritter- Hrncirik CA; Witanowski LS; Tillapaugh-Fay G; Urrutia E 《Radiology》1987,162(2):575-577
Radioimmunoimaging of fresh canine venous thrombi with a murine monoclonal antibody specific for human and dog fibrin has been reported. Successful imaging of canine deep venous thrombi 1, 3, and 5 days old at the time of antibody injection is reported. Images were positive in all dogs, and the uptake of fibrin-specific antibody was equivalent to that of fresh thrombi. 相似文献