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A previously developed method for achieving patient relocation in fractionated stereotactic radiotherapy (attachment of an infrared fiducial system to a bite tray) relies on the integrity of a bite tray system that incorporates moulding to the patient's upper dentition. Reproducible and accurate patient positioning requires stability of the bite tray and mould during the full treatment process, both during the time the bite tray is inserted in the patient's mouth, and between separate bite tray insertions. The optimum construction method for a stable reproducible tray has not been sufficiently investigated. We undertook a study to identify factors which might influence the integrity of the hard palate bite tray system. Reprosil Fast Set Putty was used to construct 3 impression conditions; teeth only; teeth and alveolar sulcus; and teeth, alveolar sulcus, and the hard palate. Reproducibility was assessed by volunteers inserting the impressions multiple times and recording the locations of 8 standard reference points. Our results showed the optimal impression technique (i.e., the one that led to the smallest ranges in positional and rotational errors) was that which incorporated the teeth, alveolar sulcus, and hard palate.  相似文献   
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Proximal femoral focal deficiency, an uncommon congenital anomaly, necessitates early radiologic classification for surgical planning and treatment. Objective radiographic criteria, including femoral length index, acetabular depth index, acetabular angle index, and shape of the proximal femur were determined in 49 patients before cartilaginous ossification of the femoral capital epiphysis; final classification was based on follow-up radiographs or findings at arthrography or surgery. These parameters were analyzed to determine the accuracy and contributions of each in classification. Correct classification into one of three groups was possible in 86% of cases with use of three of the parameters: femoral length index, acetabular depth index, and shape of the proximal femur. The acetabular angle was found to contribute insignificantly to classification. Magnetic resonance imaging, used in only one case, depicted the nonossified cartilaginous femoral capital epiphysis, thus obviating the need for invasive diagnostic procedures and facilitating early classification.  相似文献   
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Background: Recent development of extracorporeal magnetic stimulation (ECMS) which uses current‐changing magnetic fields allows the induction of electrical stimulation in the desired deep tissue. Recent study showed the sacral nerve stimulation reduces corticoanal excitability that may play a functional role in anal continence mechanisms. Preliminary study shows that ECMS of sacral nerve can modify pelvic floor function and expel rectal balloon in patients with pelvic floor dyssynergia (PFD). Aims: To evaluate the effect of ECMS compared with biofeedback therapy (BF) in patients with PFD. Methods and Materials: Thirty‐eight patients who fulfilled Rome II criteria for PFD by colon transit time and anorectal function tests, were randomly treated with 8 sessions of ECMS (2/weeks; n = 19) at prone position or BF (2/weeks; n = 19) at sitting position. Stimulation parameters were set at 50–80% of maximum intensity, 10 and 50 Hz frequency, 3 s burst length with 3 and 6 s off using arm‐typed stimulator (BioCom‐1000, Mcube Co., Korea). Symptom scores for constipation with/without anorectal function test were repeatedly measured after each treatment. Response was defined as 50% or more decreased symptom score after treatment (partial response: 30–50%, poor: <30%). Results: Fifteen patients (age 49.1 ± 13.4 years, mean ± SD; 4 men) completed 8 session of BF and 14 patients (54.5 ± 17.6 years, 3 men) completed 8 session of ECMS. Four patients of BF group discontinued treatment due to unsatisfactory therapeutic effect (n = 1) and withdrew consent (n = 3) and 5 patients of ECMS group discontinued treatment because of same reasons (n = 1, 4). Total symptom scores were significantly decreased after treatment of 8 session in both treatment groups (13.4 ± 6.6 vs. 4.3 ± 4.0 for BF, p = 0.009; 14.9 ± 5.6 vs. 3.4 ± 4.0 for ECMS, p < 0.001). Bowel movements per week were also significantly increased after treatment in both groups (median 2 vs. 7 for BF, p = 0.035; median 2 vs. 7 for ECMS, p = 0.008). Thirteen out of 15 patients showed response in BF group and 12 out of 14 showed good response in ECMS group. No adverse effects in both groups. Conclusions: ECMS is as effective as BF for the treatment of PFD. Long‐term effect of ECMS for the patients with pelvic floor dyssynergia need to be evaluated in the near future.  相似文献   
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The effects of candoxatrilat (cis-4-([2-carboxy-3-(2-methoxyethoxy)propyl]-1-cyclopentanecarbonyla mino)- 1-cyclohexane carboxylic acid) and the ring-deleted atrial natriuretic factor (ANF) analogue C-ANF4-23 (des[Gln18, Ser19, Gly20, Leu21, Gly22]ANF4-23-NH2) on the clearance of (3-[125I]iodotyrosyl28)ANF (125I-ANF) were studied in both intact and nephrectomized anaesthetized rats. HPLC analysis was used to verify that the 125I-labelled material isolated by solid phase extraction of rat plasma was intact ANF. In intact animals, clearance of 125I-ANF was biphasic with a T1/2 alpha of 17 sec and T1/2 beta of 95 sec. Volume of distribution (Vd) was 564 mL/kg and plasma clearance (Clp) 248 mL/min/kg. Candoxatrilat, over the dose range 0.01-10 mg/kg i.v., increased T1/2 beta (by a maximum of 56%) and decreased Clp (by up to 52%) with no effect on T1/2 alpha or Vd. C-ANF4-23 (10 micrograms/kg+1 microgram/kg/min i.v.) reduced Vd (by 57%) and Clp (by 54%) with no effect on T1/2 beta, whilst abolishing the T1/2 alpha phase in over 50% of animals. Increasing the dose of C-ANF4-23 did not increase the effect on any of these parameters, apart from a small increase in T1/2 beta. Combining the two agents resulted in a substantial decrease in Clp (76%) whilst the reduction in Vd and increase in T1/2 beta were comparable to those seen with C-ANF4-23 and candoxatrilat alone, respectively. In nephrectomized rats, the pharmacokinetics of 125I-ANF and the changes induced by candoxatrilat were similar to those observed in intact animals, whilst the effects of C-ANF4-23 alone were greater than in intact animals. The combination of C-ANF4-23 and candoxatrilat again produced a substantial increase in T1/2 beta (153%) and decreases in Vd (55%) and Clp (78%) in nephrectomized animals, although these changes could not be distinguished from those seen in intact animals treated with the same combination. Our studies indicate that neutral endopeptidase and ANF-C receptors are both major, and approximately equal, clearance mechanisms for 125I-ANF, together accounting for at least 75% of the total clearance of this peptide in the rat.  相似文献   
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