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排序方式: 共有413条查询结果,搜索用时 15 毫秒
71.
AIM: The purpose of this study was to evaluate clinically and radiographically pulpotomies carried out under intrapulpal injection of anaesthetic solution. METHODOLOGY: Forty-one permanent mandibular molar teeth presenting with deep carious lesions and/or exposed pulps, with or without periapical changes on radiographic examination, were treated with pulpotomy and dressed with calcium hydroxide. The teeth were divided into three groups. Group A consisted of 15 teeth, where intrapulpal anaesthesia was administered by a slow injection of lidocaine hydrochloride 2%. Group B, with 14 teeth, where intrapulpal anaesthesia was obtained with lidocaine hydrochloride 2% with adrenaline 1:100,000. Group C consisted of 12 teeth in which anaesthesia was performed with a mandibular block using prilocaine hydrochloride 3% with felypressin 1: 100,000. Healing was evaluated using clinical and radiographic criteria: dentine barrier formation, absence of clinical symptoms and resolution of periapical involvement. RESULTS: After an observation time of 6-8 weeks (postoperative control) and 24-32 weeks (intermediate control), healing occurred in 13 teeth from group A (87%), in 11 teeth from group B (79%) and in 10 teeth from group C (83%). No statistical difference was demonstrated between the three groups (Fisher's exact test). CONCLUSIONS: Based on the methodology adopted, intrapulpal injection of anaesthetic solution did not impair healing in pulpotomized teeth. 相似文献
72.
Pereira CL Demarco FF Cenci MS Osinaga PW Piovesan EM 《Clinical oral investigations》2003,7(2):116-119
MAIN PROBLEM: The microfill veneering of hybrid composite restorations has been indicated to improve esthetics. Also, polyethylene fiber reinforcement has been proposed for use in composite restorations in high-stress clinical situations. However, minimal information in the literature addresses the influence of such combinations on the resistance to fracture. The purpose of this study was to investigate the flexural strength of two composites, a microfill and a hybrid, the effect of their combination, and the influence of polyethylene fiber reinforcement. MATERIALS AND METHODS: Twenty-eight specimens were prepared using a standard metallic mold (20x2x2 mm) and divided into groups of seven each: Filtek Z-250 (3M ESPE, St. Paul, Minn., USA) (group I), Filtek A-110 (3M ESPE) (group II), Filtek Z-250 combined with Filtek A-110 (group III), and Filtek Z-250 combined with polyethylene fiber (Ribbond, Seattle, Wash., USA) (group IV). The specimens were stress-loaded to fracture in a three-point bending device according to International Standardization Organization (ISO) 4049. RESULTS: Data were analyzed using analysis of variance and Tukey's test at a 0.05 level of significance. No statistically significant differences were observed between groups I and IV. Group II, however, exhibited statistically lower resistance to fracture than the other groups. Group III presented intermediate results, showing statistically higher fracture resistance than group II but lower than group I. CONCLUSIONS: With the methodology employed, microfill composite presented the lowest flexural strength, but its association with hybrid composite increased the resistance to fracture. The combination of polyethylene fiber and hybrid composite did not present higher flexural strength than hybrid composite alone. 相似文献
73.
This study evaluated the root-end sealing ability of mineral trioxide aggregate (MTA Angelus), reinforced zinc oxide-eugenol cement (Super EBA), resin-modified glass ionomer (Vitremer) and zinc-free amalgam (GS-80) (control). The root canals of eighty human lower molars were accessed, cleansed, shaped and obturated. Apexes were resected and cavities were prepared. Teeth were divided into 4 groups of 40 cavities, root-end filled with the materials, and immersed in methylene blue for 72 h at 37 degrees C. Roots were then sectioned transversally at each millimeter and evaluated under magnification, observing the dye penetration in each section. Data were evaluated using Kruskal-Wallis test at a 5% level of significance, showing the differences among all materials (p < 0.001). The crescent order of microleakage was MTA < Vitremer < Super EBA < amalgam. Higher leakage levels were observed in the first millimeter sections of amalgam, Vitremer and MTA, when compared with the third millimeter section (p < 0.05). 相似文献
74.
75.
Aim The aim of the present study was to review the current literature on oppressed group behaviours in nursing, with emphasis on interventions to change the behaviours, and on instruments that have been developed to measure it.
Background Oppressed group behaviours have been described in nurses for over two decades and their presence has been related to decreased nurse self-advocacy, and other negative aspects of the nursing workplace.
Evaluation Systematic review of the literature on oppressed group behaviour in nursing.
Key issues Oppressed group behaviours are frequently found in nurses. Interventions have been created and tested to decrease oppressed group behaviours.
Conclusion Oppressed group behaviours are frequently found in nurses. Interventions exist that can decrease oppressed group behaviours and the decrease is related to increased work force performance, satisfaction and retention of nurses in the workplace.
Implications for nurse managers Nurse Managers can improve the workplace by measuring oppressed group behaviours and utilizing interventions to break the cycle of oppression in the workplace culture. Utilizing these innovations improve the workplace culture for nursing. 相似文献
Background Oppressed group behaviours have been described in nurses for over two decades and their presence has been related to decreased nurse self-advocacy, and other negative aspects of the nursing workplace.
Evaluation Systematic review of the literature on oppressed group behaviour in nursing.
Key issues Oppressed group behaviours are frequently found in nurses. Interventions have been created and tested to decrease oppressed group behaviours.
Conclusion Oppressed group behaviours are frequently found in nurses. Interventions exist that can decrease oppressed group behaviours and the decrease is related to increased work force performance, satisfaction and retention of nurses in the workplace.
Implications for nurse managers Nurse Managers can improve the workplace by measuring oppressed group behaviours and utilizing interventions to break the cycle of oppression in the workplace culture. Utilizing these innovations improve the workplace culture for nursing. 相似文献
76.
Transfusion-associated graft-versus-host disease: risk due to homozygous HLA haplotypes 总被引:11,自引:0,他引:11
BACKGROUND: Transfusion-associated graft-versus-host disease (TA-GVHD) may occur in transfusions of blood from HLA-homozygous persons to HLA- heterozygous persons who share a haplotype. STUDY DESIGN AND METHODS: Two mathematical models were developed to calculate the upper and lower limit of the associated risks in various populations using a combination of serology- and DNA sequence-based HLA haplotype frequencies. RESULTS: For nondirected transfusion, the range of the estimated risk in United States whites is 1 of 17,700 to 39,000 (1/6,900-48,500 in Germans; 1/1,600-7,900 in Japanese). The risk in directed donation between parents and children is increased at least 21- fold for US whites, 18-fold for Germans, and 11-fold for Japanese. CONCLUSION: For nondirected transfusions, the estimates of TA-GVHD risk derived in this model are lower than estimates of previously published models, are in better agreement with the clinical experience, and explain in part the observed discrepancy between TA-GVHD incidence in the United States and that in Japan. Most notably for US whites, the relative increase in risk in directed transfusion is larger than previously thought. 相似文献
77.
Hamers F Downs AM Alix J Brunet JB 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》1997,2(5):36-37
In 1996, 24 920 AIDS cases were reported in the WHO European Region, bringing the cumulative total to 185 808 cases including 6969 (4%) paediatric cases (<13 years). For the first time since the start of the epidemic, the annual number of cases reported d 相似文献
78.
Cell-specific expression of plasma membrane calcium ATPase isoforms in retinal neurons 总被引:5,自引:0,他引:5
Krizaj D Demarco SJ Johnson J Strehler EE Copenhagen DR 《The Journal of comparative neurology》2002,451(1):1-21
Ca(2+) extrusion by high-affinity plasma membrane calcium ATPases (PMCAs) is a principal mechanism for the clearance of Ca(2+) from the cytosol. The PMCA family consists of four isoforms (PMCA1-4). Little is known about the selective expression of these isoforms in brain tissues or about the physiological function conferred upon neurons by any given isoform. We investigated the cellular and subcellular distribution of PMCA isoforms in a mammalian retina. Mouse photoreceptors, cone bipolar cells and horizontal cells, which respond to light with a graded polarization, express isoform 1 (PMCA1) of the PMCA family. PMCA2 is localized to rod bipolar cells, horizontal cells, amacrine cells, and ganglion cells, and PMCA3 is predominantly expressed in spiking neurons, including both amacrine and ganglion cells but is also found in horizontal cells. PMCA4 was found to be selectively expressed in both synaptic layers. Optical measurements of Ca(2+) clearance showed that PMCAs mediate Ca(2+) extrusion in both rod and cone bipolar cells. In addition, we found that rod bipolar cells, but not cone bipolar cells possess a prominent Na(+)/Ca(2+) exchange mechanism. We conclude that PMCA isoforms are selectively expressed in retinal neurons and that processes of Ca(2+) clearance are different in rod and cone bipolar cells. 相似文献
79.
Siam Oottamasathien Karin Williams Omar E Franco John C Thomas Katrina Saba Neil A Bhowmick Andrea Staack Romano T Demarco John W Brock Simon W Hayward John C Pope 《Developmental dynamics》2006,235(10):2795-2801
Tissue recombination is a powerful method to evaluate the paracrine-signaling events that orchestrate the development of organs using the in vivo environment of a host rodent. Studies have reported the successful generation of primary cultures of rodent bladder urothelium, but none have reported their use to recapitulate bladder tissue with tissue recombination. We propose that primary cultured bladder urothelium, when recombined with inductive embryonic bladder mesenchyme, will form bladder tissue in a recombination model. Adult rat bladders were isolated and urothelium obtained. Sheets of bladder urothelium were re-suspended in collagen and maintained in tissue culture. After expansion (>20 passages), the urothelium was recombined with embryonic day-14 mouse bladder mesenchyme, then grafted beneath the renal capsule of immunocompromised mouse hosts. Grafts were harvested after 28 days. Control grafts were performed with bladder mesenchyme alone, cultured bladder urothelium alone, and collagen matrix alone. Final tissues were evaluated with staining and immunohistochemistry (H&E, Gomori's trichrome, broad-spectrum uroplakin, and smooth muscle actin alpha and gamma). Immunocytochemistry on cultured urothelium for broad-spectrum keratin, vimentin, and broad-spectrum uroplakin confirmed pure populations, void of mesenchymal contaminants. Staining of recombinant grafts demonstrated bladder tissue with mature urothelium and stromal differentiation. Control tissues were void of bladder tissue formation. We have successfully demonstrated that a chimeric bladder is formed from primary cultured bladder urothelium recombined with embryonic bladder mesenchyme. This is a powerful new tool for investigating the molecular mechanisms of bladder development and disease. Future applications may include the in vitro genetic manipulation of urothelium and examining those effects on growth and development in an in vivo environment. 相似文献
80.
Saeed M; Braun SD; Cohan RH; Sussman SK; Illescas FF; Perlmutt LM; Newman GE; Dunnick NR 《Radiology》1987,165(2):345-349
The choice of a contrast agent for pulmonary angiography has important implications for patient comfort, image quality, and perhaps the safety of the procedure, particularly for "high-risk" patients. In a prospective study the nonionic, low-osmolality agent iopamidol eliminated the problem of image degradation due to coughing, and patients showed excellent tolerance for it. However, pressure measurements obtained within 3-5 minutes of injection of iopamidol and diatrizoate sodium meglumine 76% showed no significant difference in the hemodynamic effects of the two contrast agents, either for normotensive or for pulmonary hypertensive patients. Contrary to a common presumption, pulmonary hypertension by itself did not appear to increase the risk of pulmonary angiography. The theoretic presumption of greater hemodynamic stability with low-osmolality contrast agents was not clinically evident in this trial with iopamidol. At present, enhanced patient comfort and improved image quality remain the only confirmed bases for choosing this contrast agent for pulmonary angiography. 相似文献