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991.
BACKGROUND: Renal itch is a relatively common and distressing problem for patients with chronic renal failure. Ondansetron, a serotonin type 3 receptor antagonist was developed for relief of chemotherapy induced nausea. Recently, anecdotal reports describe relief of renal itch with ondansetron. OBJECTIVES: We performed a double-blind randomized placebo-controlled trial to objectively assess the effectiveness of ondansetron in renal itch. PATIENTS AND METHODS: With approval from the local ethical committee, 24 patients on haemodialysis were enrolled in the trial. On a random basis 14 patients were blindly allocated to the ondansetron-placebo sequence and 10 to the placebo-ondansetron sequence. Baseline values for itch were obtained for 7 days before the treatment period and there was a 7-day washout between the treatment periods. During the treatment patients received either 8 mg of ondansetron three times a day or a placebo tablet three times a day for 2 weeks. Patients were asked to record the severity of their pruritus on a visual analogue scale (VAS) twice a day. At the end of the study patients were asked blindly which treatment they had preferred. RESULTS: Seventeen patients completed the trial. Pruritus decreased by 16% (95% CI: 0.5-32%) during active treatment and by 25% (95% CI: 9-41%) during treatment with placebo. The change in VAS scores during treatment with ondansetron (P = 0.04) and placebo (P = 0.01) were both significant. Eleven patients expressed a preference, seven for placebo and four for ondansetron. CONCLUSIONS: Our results show that ondansetron is no better than placebo in controlling renal itch.  相似文献   
992.
A retrospective study using models was performed to evaluate the incremental expansion that occurred during mandibular lip bumper therapy in 44 adolescent patients. The purpose was to determine whether expansion occurs evenly between appointments or whether it attenuates with treatment time. Dental cast measurements were made for arch width and arch length. Treatment duration was broken into near-equal time segments and compared. Results showed that about 50% of the total expansion achieved occurred within about the first 100 days. Forty percent of the total amount of expansion occurred during the next 200 days, with only about 10% of the total expansion occurring after the first 300 days. It is unnecessary to have the appliance in place for longer than 300 days. The percentage of expansion that occurred at each time segment was not related to whether the patient had concomitant maxillary expansion.  相似文献   
993.
This article reviews the kinds of electronic transactions required under the Health Insurance Portability & Accountability Act (HIPAA) and relates them to relevant data contained in an electronic oral health record (EOHR). It also outlines the structure of HIPAA transactions using the claim transaction as an example. The relationship of the HIPAA resource management function to those of patient care are discussed. The discussion points out potential future uses of other existing resource management transactions to realize the maximum potential of linking the primary patient care functions to those functions related to managing resources in support of that care. This is needed in all aspects of oral health using the informatics standards activities in which the American Dental Association (ADA) actively participates. The article concludes by providing the dentist a perspective on how to relate these capabilities to his/her individual practice setting.  相似文献   
994.
BACKGROUND AND PURPOSE: To compare the efficacy and vascular toxicity of embolization with radical (NBCA+metacryloxysulpholane=CS) versus conventional anionic (NBCA alone=CA) polymerization of NBCA. Materials and methods: Under continuous digital subtracted angiography (DSA) recordings, a 0.2 mL volume of identical glue mixtures were injected in a single-step procedure, concomitantly, in left and right (with CS and CA, respectively) renal arterial branches (RAB) and ascending pharyngeal arteries (APA) in 8 swines. Arterial histopathology and morphometry of inflammation were investigated at 2 weeks. RESULTS: Complete embolization was achieved with equivalent cast homogeneity on DSA with both NBCA mixtures in RAB and APA. Inflammatory crowns in APA and RAB were significantly lower in CS - than in CA-treated sites (p<0.001). CS plug was scarcely adhesive to the vascular wall, and pulled apart from the wall by a residual thrombotic lining; in contrast with CA casts that were strongly adhesive to walls with endothelium stripping. CONCLUSIONS: Anionic and radical polymerization of NBCA embolization was identical with regards to occlusion rate; whereas radical pathway of polymerization with cyanoacrylates lowered histotoxicity with a less sustained adhesiveness of casts against vascular walls.  相似文献   
995.
PURPOSE: Morphological classifications designed by experts to stratify neoplasms according to biological potential must define categories that are reproducible among practitioners or the schemes actually create the heterogeneous populations that they seek to avoid. The application of the 1998 World Health Organization/International Society of Urologic Pathology scheme for urothelial neoplasms was studied in a community practice setting. We documented interpretive discrepancies for each category of neoplasm and determined whether a period of pathologist education may have a positive effect on the frequency of discrepant interpretations. The results suggest that patients may benefit from modifying the classification system. MATERIALS AND METHODS: A consecutive series of specimens was divided into learning and study sets that were each independently examined by 3 pathologists. Specimens in the learning set were interpreted without previous structured education, while those in the study set were interpreted immediately after intensive education. Interpretations for each specimen were compared and interpretive discrepancies were analyzed. RESULTS: Case distribution after education was similar among the pathologists but interpretations for any particular specimen often differed. The level of interpretive discrepancies varied according to the morphological similarity among categories in the classification scheme and was not necessarily decreased by education. When pathologists were required to discriminate between papillary urothelial neoplasm of low malignant potential and low grade carcinoma, the discrepancies were 50% after education compared with 39% before education. In contrast, there were no discrepancies when the discrimination was between papillary urothelial neoplasm of low malignant potential and high grade carcinoma or carcinoma in situ. Eliminating categories with poor reproducibility markedly improved the likelihood of unanimous agreement among practitioners but a probably irreducible level of 10% discrepancies remained. CONCLUSIONS: The 1998 World Health Organization/International Society of Urologic Pathology classification of urothelial neoplasms requires certain discriminations that cannot be reliably made by practitioners. Modifying the scheme to create categories of low grade neoplasm and high grade carcinoma would markedly increase its practical value to patients without significantly altering patient care.  相似文献   
996.
997.
This study compared the incidence of vomiting and the sedative effectiveness of ketamine to a ketamine-prornethazine combination in pediatric dental patients. Twenty-two patients with American Society of Anesthesiologists' classification I physical status who were between the ages of 21 and 43 months were randomly divided into 2 groups. The control group received 10 mg/kg of ketamine orally, whereas the experimental group received 10 mg/kg of ketamine and 1.1 mg/kg of promethazine orally. Nitrous oxide in oxygen was supplemented between 35 and 50%. Each patient received 1 or 2 quadrants of restoration by one operator. Heart rate, blood pressure, and oxygen saturation were monitored and recorded during the treatment. Crying, alertness, movement, and overall general behavior were rated using the scale by Houpt et al. A dentist-anesthesiologist conducted the vital sign monitoring and behavioral assessment. Ketamine combined with promethazine eliminated the incidence of vomiting. A 2 x 2 chi-square contingency table showed a statistical difference between the 2 groups at P < .05 (control group, 27%; experimental group, 0%). Ketamine alone yielded better sedations than the combined agents as shown by the Mann-Whitney U statistical analysis (P < .05). Ketamine and a ketamine-promethazine combination are effective in the sedation of pediatric dental patients.  相似文献   
998.
Kouchoukos NT  Masetti P  Rokkas CK  Murphy SF 《The Annals of thoracic surgery》2002,74(5):S1800-2; discussion S1825-32
BACKGROUND: Management of the enlarged, chronically dissected aorta after previous repair of acute ascending aortic dissection or after a previous cardiac operation may present a formidable technical challenge and the optimal method of management is not clearly established. METHODS: Twenty-one patients with chronic type A aortic dissection (mean age 57 years) underwent resection of the ascending aorta, the aortic arch, and varying segments of the descending thoracic aorta. Single-stage replacement with perfusion of the aortic arch first to minimize the duration of brain ischemia and a bilateral anterior thoracotomy (clamshell) incision were used. Fourteen patients had undergone previous repair of acute type A dissection. Seven patients had type A dissection after aortic valve replacement (3 patients) or coronary artery bypass (4 patients). Marked enlargement of the aorta distal to the left subclavian artery precluded a two-stage repair. The mean interval between the initial and reoperative procedures was 69 months (range, 5 to 249). RESULTS: There was 1 (4.8%) hospital death. Four patients required reoperation for bleeding. One patient required a right ventricular assist device that was successfully removed. Ten patients required assisted ventilation for more than 48 hours. All were successfully weaned from ventilatory support. No patient had a stroke or other adverse neurologic outcome. There has been 1 late death (mean follow-up 2 years). CONCLUSIONS: The single-stage, arch-first replacement technique is a safe and effective procedure for patients who require extensive reoperations for chronic expanding type A dissection.  相似文献   
999.
Kouchoukos NT  Masetti P  Rokkas CK  Murphy SF 《The Annals of thoracic surgery》2002,74(5):S1885-7; discussion S1892-8
BACKGROUND: Hypothermic cardiopulmonary bypass with circulatory arrest is an important adjunct for operations on the distal aortic arch, the descending thoracic, and the thoracoabdominal aorta. The safety and efficacy of this technique when compared with other adjuncts (ie, simple aortic clamping, partial cardiopulmonary bypass, regional hypothermia) is not clearly established. METHODS: One hundred and ninety-two patients (age range, 20 to 83 years) with descending thoracic or thoracoabdominal aortic disease had resection and graft replacement of the involved aortic segments using hypothermic cardiopulmonary bypass and intervals of circulatory arrest (mean, 38 minutes). The technique was used when the location and severity of disease precluded placement of clamps on the proximal aorta (31 patients) or (in 161 patients) when extensive thoracic (47) or thoracoabdominal (114) aortic disease was present, and the risk for development of spinal cord ischemic injury was judged to be increased. Lower intercostal and lumbar arteries were attached separately to the aortic graft in 101 of the 161 patients (63%) who had extensive aortic replacement. No other adjuncts for spinal cord protection were used. RESULTS: The 30-day mortality was 6.8% (13 patients). It was 40% (8 of 20) for patients having emergent operations (acute aortic dissection or rupture) and 2.9% (5 of 172) for all others (p < 0.001). The 90-day mortality was 12.5% (24 patients). Paraplegia occurred in 4 and paraparesis in 1 (full recovery) of the 186 operative survivors whose lower limb function could be assessed postoperatively (2.7%). Among the 109 survivors with thoracoabdominal aortic disease, early paraplegia occurred in 1 of 36 with Crawford extent I, 0 of 42 with extent II, and 2 of 31 with extent III disease. One patient (extent II) developed paraplegia on the 9th postoperative day after a hypotensive episode. None of the 47 patients with aortic dissection developed paralysis. Among the 186 operative survivors, renal dialysis was required in 4 patients (2.2%), prolonged inotropic support in 18 (10%), reoperation for bleeding in 9 (5%), mechanical ventilation (> or = 48 hours) in 64 (34%), and tracheostomy in 17 (9%). Four patients (2%) sustained a stroke. CONCLUSIONS: Hypothermic cardiopulmonary bypass with circulatory arrest provides safe and substantial protection against paralysis and renal, cardiac, and visceral organ system failure that equals or exceeds that of other currently used techniques but without the need of other adjuncts.  相似文献   
1000.
Periacetabular osteotomy is an extremely effective treatment for the spherical dysplastic hip without significant secondary osteoarthrosis. Yet, the reliability of the procedure in patients with some degree of secondary osteoarthritis, asphericity, or associated deformities remains undefined. The purpose of the current study was to analyze a group of patients treated by periacetabular osteotomy for dysplasia to identify preoperative factors that predict outcome. Ninety-five consecutive hips in 87 patients treated by periacetabular osteotomy were studied prospectively. Of this group, 52 hips in 49 patients were studied for a minimum of 2 years after surgery. Forty-six of the 52 procedures resulted in hips with stable or improved cartilage space intervals. By Tonnis category, there were 0 of 21 failures in Grade 1, four of 22 failures in Grade 2 (18%), one of eight failures in Grade 3 (12.5%), and one of one failure in Grade 4 hips. Five of the six failures had factors identifiable on preoperative radiographs that separated these hips from the successful reconstructions. This study shows that periacetabular osteotomy can reliably produce a stable hip, even in the presence of Grade 3 arthrosis, provided that the joint shows an improved cartilage space interval on the preoperative functional radiographs.  相似文献   
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