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991.
992.
Urrutia EJ; Hawkins MC; Steinbach BG; Meacham MA; Bland KI; Copeland EM d; Hawkins IF Jr 《Radiology》1988,169(3):845-847
A needle system with a retractable barb was developed for localization of nonpalpable breast lesions. The system can be repositioned without major adjustments and strongly anchors to breast tissue, eliminating failure due to dislodgment or transection of the localizing wire. Its use may necessitate fewer confirmatory radiographs, resulting in decreased radiation exposure. In addition, the needle can be retracted during surgery, to ease extraction of the specimen. 相似文献
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Computed tomography of multilocular cystic nephroma 总被引:4,自引:0,他引:4
997.
Modulation of spontaneous B-cell differentiation in macroglobulinemia by retinoic acid 总被引:2,自引:0,他引:2
We previously showed that clonal blood B cells from patients with macroglobulinemia spontaneously differentiate in vitro to plasma cells. This process is dependent on an interleukin (IL)-6 autocrine pathway. We investigate here whether all-trans-retinoic acid (RA) interferes with B-cell differentiation either in patients with IgM gammapathy of undetermined significance (MGUS) or Waldenstrom's macroglobulinemia (WM). RA at a concentration of 10(-5) to 10(-8) mol/L inhibited by 50% to 80% the in vitro differentiation of purified B cells from four of five patients with MGUS and from one of five patients with WM as assessed by the IgM content of day 7 culture supernatants. We next determined whether this effect could be related to an inhibition of IL- 6 secretion by cultured B cells and/or a downregulation of the IL-6 receptor (IL-6R), which was constitutively expressed on patients' blood B cells. A 50% to 100% (mean, 80%) inhibition of IL-6 production was found in seven of 10 patients (five with MGUS and two with WM). The IL- 6R was no more detectable on cells from patients with MGUS after 2 days of treatment with RA and slightly downregulated in patients with WM. It was of interest that B cells susceptible to the action of RA belonged mostly to patients with IgM MGUS, which reinforces our previous data showing distinct requirements for IL-6-dependent differentiation of blood B cells from patients with VM or IgM MGUS. 相似文献
998.
CPT Stephen L. Simpson MD MC Michael S. Hertzog MD MC COL Roberto H. Barja MD MC 《The Journal of hand surgery》1991,16(4):708-711
To assess the value of ultrasound in imaging the plantaris tendon, ultrasounds were done on 26 legs in 25 patients who had a variety of surgical procedures on the posterior leg. Eighteen ultrasounds were done and interpreted before operation and eight after operation by a radiologist. The sonographic results were compared with the status of the plantaris as determined at surgery. The plantaris was present in 21 of 23 patients for a prevalence of 91%. Eighteen plantaris tendons were well visualized on ultrasound for a sensitivity of 86%. Of the three false-negative results, two occurred with thinned plantaris tendons that were less than 2 mm thick and hence considered inadequate for grafting. Therefore, the sensitivity for detecting a tendon suitable for grafting was 95%. All patients with positive studies had a plantaris tendon present for a specificity of 100%. A learning curve for the radiologist was demonstrated. Ultrasound appears to be effective in the preoperative imaging of the plantaris tendon. 相似文献
999.
OBJECTIVE: To calculate the cost of heart failure in Belgium, based on an epidemiological model.
METHODS: We applied a state transition model to simulate the disease progression of heart failure over a period of 5 years, taking into account a weighted average of current practice. Costs related to current practice (1996 values) and disease progression were taken from the perspective of the health insurance. Unit costs of ambulatory care were collected through official listings; hospitalization costs for heart failure were collected from a database of 58 hospitals (ICD codes 402, 428, 429). Current practice was obtained through review of 250 patient records in primary care, starting on the day of initiating therapy up to 6 months later, and through expert interviews (2 rounds Delphi method).
RESULTS: The model indicates that the expected cost of treating heart failure in 1996 in Belgium was 318,000 Bef over 5 years, for an average number of life years of 3.59. ACE inhibitors are used in 34% of patients but are mostly applied only in higher NYHA classes (more ill patients), although studies recommend to prescribe those drugs earlier in the disease development, since they can avoid morbidity (hospitalisation) and morality. We calculated that starting earlier with ACE inhibitors and doubling their use would increase the total costs to 351,700 Bef for an extra survival time of 0.07 life years.
CONCLUSIONS: The study showed that state transition models can be applied in the assessment of the management of heart failure. Changes in the management should be expressed in extra costs per extra life year and compared to interventions in other disease areas. 相似文献
METHODS: We applied a state transition model to simulate the disease progression of heart failure over a period of 5 years, taking into account a weighted average of current practice. Costs related to current practice (1996 values) and disease progression were taken from the perspective of the health insurance. Unit costs of ambulatory care were collected through official listings; hospitalization costs for heart failure were collected from a database of 58 hospitals (ICD codes 402, 428, 429). Current practice was obtained through review of 250 patient records in primary care, starting on the day of initiating therapy up to 6 months later, and through expert interviews (2 rounds Delphi method).
RESULTS: The model indicates that the expected cost of treating heart failure in 1996 in Belgium was 318,000 Bef over 5 years, for an average number of life years of 3.59. ACE inhibitors are used in 34% of patients but are mostly applied only in higher NYHA classes (more ill patients), although studies recommend to prescribe those drugs earlier in the disease development, since they can avoid morbidity (hospitalisation) and morality. We calculated that starting earlier with ACE inhibitors and doubling their use would increase the total costs to 351,700 Bef for an extra survival time of 0.07 life years.
CONCLUSIONS: The study showed that state transition models can be applied in the assessment of the management of heart failure. Changes in the management should be expressed in extra costs per extra life year and compared to interventions in other disease areas. 相似文献
1000.