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Background: Complex procedures involving a facebow transfer and the use of lingualised teeth are deemed to have a positive influence on the chewing ability with complete dentures. Objectives: To determine if patients’ ratings of their ability to chew depend on the method of complete denture fabrication. Methods: Edentulous patients (n = 20) participated in a within‐subject crossover trial. Each patient received two sets of new complete dentures. One pair was manufactured based on intraoral tracing of centric relation and facebow transfer; semi‐anatomical teeth with lingualised occlusion denture (LOD) were chosen. The second pair was made using a simplified procedure without facebow transfer; jaw relations were recorded with wax occlusion rims, and anatomical teeth with a first premolar/canine‐guidance (CGD) were selected. The dentures were delivered in randomised order, and each was worn for 3 months. Three months after delivery, patients’ ratings of each new prosthesis were recorded on visual analogue scales for their ability to chew seven index foods. Repeated measurements analysis of variance was performed to investigate possible carry‐over effects accounting for confounding by treatment period. Results: When comparing the two treatments, participants rated their ability to chew in general, to masticate carrots, hard sausage, steak and raw apple in particular, was significantly better with the CGD (anatomical teeth) than with the LOD (p < 0.05). Conclusion: Comprehensive methods for the fabrication of complete dentures including semi‐anatomical lingualised teeth and a full registration do not seem to influence the perceived chewing ability, when compared with more simple procedures. Chewing ability for tough foods appears to benefit from the use of anatomical teeth. 相似文献
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The interactive effects of certain phytohormones (GA3, IAA or kinetin) and drought on plant-water relations and mineral accumulation of the three crop plants; maize, cowpea and
broad bean, were studied. Phytohormone applications were capable of counteracting to some extent, the adverse effects of drought
on transpiration, stomatal frequency, and leaf area.
Part 1. 相似文献
196.
Khalid Ahmed Peter H. van der Meide John L. Turk 《Cancer immunology, immunotherapy : CII》1989,30(4):213-218
Summary Some conventional and experimental anticancer drugs were tested for their effect on concanavalin-A-induced interferon release from rat splenocytes in vitro. When 2.5 × 106 rat splenocytes/ml, stimulated with 1 µg/ml concanavalin A, were incubated with various non-cytotoxic doses of the vinca alkaloid vincristine, there was an inhibition of the release of interferon in culture supernatants. The antitumour antibiotics bleomycin and Adriamycin, alkylating agents 4-hydroperoxycyclophosphamide and mafosfamide, and the immunoactive peptides FK 156 and FK565 did not affect the release of interferon under similar conditions. However, cyclosporin A, in similar experiments, markedly inhibited the release of interferon . 相似文献
197.
Gulwaiz Akhter Aiman Zafar Waseem Khan Mohmmad Jamshed 《Archives Of Phytopathology And Plant Protection》2013,46(7-8):399-407
AbstractAqueous leaf extracts of four commonly growing weeds namely Ageratum conyzoides, Elephantopus scaber, Lantana camara and Xanthium strumarium were used to evaluate their nematicidal activity on second stage juvenile of Meloidogyne incognita race-3. The juveniles were exposed to various concentration of leaf extract namely 250, 500, 1000 and 2000?ppm for 12, 24 and 48?h, respectively. All leaf extracts showed the nematicidal property in concentration and time-dependent manner. The maximum juvenile mortality was recorded in E. scaber throughout the incubation period followed by X. strumarium, L. camara and A. conyzoides. The regression and correlation of regression revealed the best concentration-dependent effect of aqueous leaf extracts on nematode mortality in E. scaber (R2?=?.751) followed by X. strumarium (R2?=?.749), A. conyzoides (R2?=?.687) and L. camara (R2?=?.756). Aqueous leaves extracts of these aforementioned weeds showed nematicidal properties, therefore, may be used as a key component of integrated disease management programme. 相似文献
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Effect of microwaves (2450-MHz) on the immune system in mice: studies of nucleic acid and protein synthesis 总被引:1,自引:0,他引:1
CBA/J adult male mice were given single or triple exposures to 2450-mHz microwaves in an environmentally controlled wave guide facility. The average absorbed dose rate for a single exposure varied from 12 to 15 mW/g. Sham-exposed mice served as controls. Lymphoid cells were collected and tested for metabolic activity on days 3, 6, and 9 following a single exposure, and on days 9, 12, and 16 following triple exposures on days 0, 3, and 6. Cells were cultured in vitro for four hours to seven days before their metabolic rates were assayed. Under these conditions, microwaves failed to produce any detectable change in deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and protein synthesis, as measured by the incorporation of methyl(3H)-thymidine (3H-TDR) (DNA substrate), 3H-uridine (3H-UR) (RNA substrate), and 3H-leucine (protein substrate) by spleen, bone marrow, and peripheral blood lymphocytes (PBL) in vitro. These data suggest that microwave-induced increases in the frequency of complement-receptor (CR)- or surface-immunoglobulin (sIg)-bearing cells were not associated with a concomitant increase in cell proliferation and/or protein synthesis, and favor the concept that microwaves under these conditions stimulate already existing B-cell precursors for maturation. 相似文献
200.
Ahmed Kheyr-Pour Scott B. Bintrim Thomas R. Ioerger Rene Remy Scott A. Hammond Tehhui Kao 《Sexual plant reproduction》1990,3(2):88-97
Summary In order to study the extent and nature of differences among various S-allele-associated proteins in N. alata, we carried out comparative studies of seven such proteins. We first isolated and sequenced cDNA clones for the Sz-, SF11-, S1-, and Sa-alleles, and then we compared the deduced amino acid sequences both of these four S-proteins and of three previously published S2-, S3-, and S6-proteins. This comparison revealed (1) an average homology of 53.8% among the seven proteins and (2) two homology classes, with Sz and SF11 in one class and S1, S2, S3, and S6 in the other class. There are 60 conserved residues, including 9 cysteines. Of the 144 variable residues, 50 were identified as hypervariable based on a calculation of their Similarity Indices. Although conserved, variable, and hypervariable residues are dispersed throughout the protein, some are clustered to form five conserved, five hypervariable, and a number of variable regions. Those variable sites which contain residues conserved within one class of S-proteins but different between classes might provide a clue to the evolutionary relationship of these two classes of S-proteins. The hypervariable residues, which account for sequence variability, may contribute to allelic specificity. 相似文献