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961.
Most periapical lesions are represented by inflammatory cysts, granulomas, abscesses or fibrous scars. These inflammatory conditions are often termed "endodontic lesions" because pulpal necrosis is the initiating event in their pathogenesis. Although rare, other clinically confusing periapical lesions have been extensively documented in numerous case reports and short case series. These lesions represent a wide range of pathosis, including various developmental cysts, infections, benign but locally aggressive lesions, and malignancies. The literature describing these lesions and the value of a histopathologic examination in diagnosis is reviewed. 相似文献
962.
BACKGROUND: Outcomes and costs of inpatient versus outpatient pediatric cardiac catheterization have not been extensively evaluated. METHODS: For a cost-consequence analysis, we reviewed the medical records and cost data in a Swiss pediatric hospital. We compared outcomes and costs of observed inpatient management versus hypothetical planned same-day discharge for patients meeting the outpatient catheterization criterions for an American pediatric hospital. RESULTS: Among 346 catheterization admissions occurring from January, 1998 through December, 1999, 179 met the American criterions for outpatient catheterization. Complications observed, and/or nursing interventions begun within 5 hours of catheterization, might have required overnight observation in 41 of the 179 admissions (22.9%). The remaining 138 patients were stable at five hours, and presumably could have been discharged the day of the procedure. Routine pre-discharge imaging detected significant complications following three interventional procedures. Postulated costs from the perspective of the provider, counting hospital and physician expenditure were calculated for the Swiss franc in 2000 at a rate of 1.69 francs for each American dollar, averaged 10,946 francs per inpatient, versus 9790 francs for outpatient treatment (p < 0.001 by paired t-test). Estimated revenue deficits, calculated as costs minus reimbursement, averaged 8565 francs per inpatient versus 1756 francs per patient treated as an outpatient. CONCLUSIONS: Half the patients being catheterized in the Swiss hospital met the external criterions for attempted outpatient catheterization. Most might have been safely discharged on the same day, with modest savings in costs, and reduced deficits in terms of revenue. Routine predischarge imaging may be more important than overnight observation. Outpatient catheterization merits prospective evaluation in Switzerland. 相似文献
963.
Dignani MC Grazziutti M Anaissie E 《Seminars in respiratory and critical care medicine》2003,24(1):89-98
Stenotrophomonas maltophilia is a ubiquitous, gram-negative organism that causes hospital-acquired infections. Persons often come in contact with S. maltophilia through environmental water sources, including hospital tap water or faucets, and it has been associated with nosocomial outbreaks of infection. S. maltophilia often infects debilitated persons and those with underlying medical conditions, including immunosuppression. Manifestations of infection include pneumonia, often in mechanically ventilated patients, bacteremia, skin and soft tissue infection, urinary tract infection, and endocarditis. Treatment of S. maltophilia infection is difficult because the organism is resistant to a number of agents typically used for hospital-acquired infections. In vitro and clinical data indicate that trimethoprim-sulfamethoxazole is the agent of choice. Beta-lactamase inhibitors such as clavulanate are also active, and combination therapy may be indicated for certain serious infections due to S. maltophilia. 相似文献
964.
Brose A Parise G Tarnopolsky MA 《The journals of gerontology. Series A, Biological sciences and medical sciences》2003,58(1):11-19
We sought to determine whether creatine monohydrate (CrM) supplementation would enhance the increases in strength and fat-free mass that develop during resistance exercise training in older adults. Twenty-eight healthy men and women over the age of 65 years participated in a whole-body resistance exercise program 3 days per week for 14 weeks. The study participants were randomly allocated, in a double-blind fashion, to receive either CrM (5 g/d + 2 g of dextrose; n = 14) or placebo (7 g of dextrose; n = 14). The primary outcome measurements included the following: total body mass, fat-free mass, one-repetition maximum strength for each body part, isometric knee extension, handgrip, and dorsiflexion strength, chair stand performance, 30-m walk test, 14-stair climb performance, muscle fiber type and area, and intramuscular total creatine. Fourteen weeks of resistance exercise training resulted in significant increases in all measurements of strength and functional tasks and muscle fiber area for both groups (p <.05). CrM supplementation resulted in significantly greater increases in fat-free mass and total body mass, as compared with placebo (p <.05). The CrM group also showed a greater increase in isometric knee extension strength in men and women, as compared with placebo (p <.05), and also greater gains in isometric dorsiflexion strength (p <.05), but in men only. There was a significant increase in intramuscular total creatine in the CrM group (p <.05). Finally, there were no significant side effects of treatment or exercise training. This study confirms that supervised heavy resistance exercise training can safely increase muscle strength and functional capacity in older adults. The addition of CrM supplementation to the exercise stimulus enhanced the increase in total and fat-free mass, and gains in several indices of isometric muscle strength. 相似文献
965.
Ethynylbicycloorthobenzoate (EBOB) is a recently developed ligand that binds to the convulsant site of the GABAA receptor. While a few studies have examined the binding of [3H]EBOB in vertebrate brain tissue and insect preparations, none have examined [3H]EBOB binding in preparations that express known configurations of the GABAA receptor. We have thus examined [3H]EBOB binding in HEK293 cells stably expressing human alpha1beta2gamma2 and alpha2beta2gamma2 GABAA receptors, and the effects of CNS convulsants on its binding. The ability of the CNS convulsants to displace the prototypical convulsant site ligand, [35S]TBPS, was also assessed. Saturation analysis revealed [3H]EBOB binding at a single site, with a K(d) of approximately 9 nM in alpha1beta2gamma2 and alpha2beta2gamma2 receptors. Binding of both [3H]EBOB and [35S]TBPS was inhibited by dieldrin, lindane, tert-butylbicycloorthobenzoate (TBOB), PTX, TBPS, and pentylenetetrazol (PTZ) at one site in a concentration-dependent fashion. Affinities were in the high nM to low microM range for all compounds except PTZ (low mM range), and the rank order of potency for these convulsants to displace [3H]EBOB and [35S]TBPS was the same. Low [GABA] stimulated [3H]EBOB binding, while higher [GABA] (greater than 10 microM) inhibited [3H]EBOB binding. Overall, our data demonstrate that [3H]EBOB binds to a single, high affinity site in alpha1beta2gamma2 and alpha2beta2gamma2 GABAA receptors, and modulation of its binding is similar to that seen with [35S]TBPS. [3H]EBOB has a number of desirable traits that may make it preferable to [35S]TBPS for analysis of the convulsant site of the GABAA receptor. 相似文献
966.
This study set out to explore the frequency and correlates of suicidal ideation in a community sample of school-aged adolescents living in a northeastern area of Italy. The study involved a mixed male–female sample of 1000 adolescents, corresponding to 10% of the young population aged 15–19 in the district. We investigated psychological distress through the revised Symptom Checklist (SCL-90-R), from which we also derived our indicators on suicidality (items concerning hopelessness and suicidal ideation). Propensity to aggression was measured with an Italian version of the Aggression Questionnaire. Females scored significantly higher than males on all SCL-90-R subscales, with the exception of the hostility subscale. In our sample, 30.8% of females and 25.3% of males reported having thought about suicide; one adolescent out of 20 reported suicidal ideation of high intensity (5% out of the total sample in both genders). Males scored significantly higher than females on the Aggression Questionnaire. Both males and females who reported suicidal feelings had significantly higher scores on the Aggression Questionnaire than did those who denied suicidal ideation. Suicidal ideation is a rather widespread occurrence among adolescents and correlates with other indicators of psychological distress. Psychological distress in adolescence might also be expressed through turbulent behaviors and conduct disorders. Identification of the mental disorders underlying a higher propensity to aggression might help to prevent other negative outcomes such as suicide. 相似文献
967.
968.
Stabellini G Carinci F Luigi Bedani P Calastrini C De Mattei M Scapoli L Caruso A Calvitti M Locci P 《Transplantation》2002,73(10):1676-1679
Cyclosporin A is a powerful immunosuppressive drug that has had a major impact on transplant therapy. It apparently links to different enzymatic pathways, and affects multiple enzymatic systems. Transforming growth factor beta induces the deposition of glycosaminoglycans, proteoglycans, and collagen fibers in the extracellular matrix. The aim of this study of normal and hypertrophic human gingival fibroblast cultures was to evaluate the cytoskeletal and extracellular changes in glycosaminoglycan secretion due to the presence of cyclosporin A and transforming growth factor beta. The results showed that there is an increase in total and individual classes of extracellular glycosaminoglycans in the presence of cyclosporin A and transforming growth factor beta, but the action of the latter was significantly greater. Immunohistochemical analysis of the cytoskeleton did not reveal any morphological differences between treated and control cells. Our data suggest that the biochemical changes in the extracellular matrix are caused more by cytokine, and that cyclosporin A does not induce any morphological changes in fibroblast cultures derived from hypertrophic and normal gingiva. 相似文献
969.
Neumann CP Gogălniceanu D Tatarciuc MS Costan VV 《Revista medico-chirurgical?? a Societ????ii de Medici ??i Naturali??ti din Ia??i》2002,106(1):174-177
The quickly and exactly method of location of the hinge-axis is based on the moiré effect, produced between two superposed optical nets, one of it being moved. A face bow is fixed on the mandible to the occlusion rim. Two optical devices are mounted on the bottoms of the face bow. Two other optical nets are applied on the skin, corresponding to the TMJ. During the opening movements of the mandible when a pure rotation of the mandibular condiles take place on the TMJ, the optical nets are displaced and me exactly register the place corresponding to the rotation axe and we can note on the skin the hinge axis. The checkout was done using a phanthom achieved in our department, consisting of a skull made up of polyestheric resins and an elastic element made up of PVC. 相似文献
970.
Sustained increases of plasma homocysteine,copper, and serum ceruloplasmin after coronary artery bypass grafting 总被引:2,自引:0,他引:2
Jeremy JY Shukla N Angelini GD Day A Wan IY Talpahewa SP Ascione R 《The Annals of thoracic surgery》2002,74(5):1553-1557
BACKGROUND: Homocysteine (Hcy) is an independent risk factor for coronary artery disease, but there are no reports on Hcy levels in patients undergoing coronary artery bypass graft (CABG) surgery. Interactions between Hcy and copper may mediate the vasculopathic impact of Hcy, and this may play a role in vein graft failure. The aim of this study was to assess the perioperative levels of Hcy, copper, ceruloplasmin (CP), folate, and vitamin B12 in patients undergoing myocardial revascularization surgery. METHODS: Blood samples were taken from 55 consecutive patients undergoing elective conventional CABG (43 male; mean age, 63.2 +/- 5.2 years) 1 day preoperatively and postoperatively at 1 day, 6 days, and 6 weeks. Hcy, copper, CP, red cell folate, vitamin B12, creatinine, and C-reactive protein (CRP) were then measured using standard clinical chemistry methods. The same protocol was applied to 10 patients (7 male; mean age, 63.3 +/- 5.2 years) undergoing off-pump coronary artery bypass (OPCAB) surgery. RESULTS: In the conventional CABG group, there were significant increases in the plasma concentrations at 6 days and 6 weeks postoperatively of Hcy (from 10.1 to 11.6 and 13.5 micromol/L, respectively), plasma copper (from 13.5 to 20.3 and 18.5 micromol/L), and serum ceruloplasmin (from 0.3 to 0.41 and 0.44 g/L). CRP and vitamin B12 were elevated at 6 days but not 6 weeks after the operation. In contrast, red cell folate and creatinine were not significantly changed. The subgroup analysis for the OPCAB patients showed the same trend as for the conventional group. CONCLUSIONS: Coronary surgery precipitates a significant and sustained increase in the blood concentrations of Hcy and copper, which is not due to a decrease in folate and vitamin B12, altered renal function, or inflammation. Further studies are required to establish whether the concomitant increase in Hcy and copper plays an etiological role in vein graft disease. 相似文献