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991.
Comparison of microbial composition in the subgingival plaque of adult crowded versus non-crowded dental regions 总被引:2,自引:0,他引:2
Chung CH Vanarsdall RL Cavalcanti EA Baldinger JS Lai CH 《The International journal of adult orthodontics and orthognathic surgery》2000,15(4):321-330
It has been reported in the literature that certain species of bacteria (periodontopathogens) present in the subgingival plaque are associated with destructive periodontal disease. The purpose of this study was to investigate and compare the presence and proportional distribution of periodontopathogens in the subgingival plaque of adult crowded versus non-crowded dental regions. Thirty adult patients with anterior dental crowding were selected from the Orthodontic Clinic of the University of Pennsylvania. After orthodontic records were taken and the periodontal examination was performed, subgingival plaque samples were collected from crowded (experimental) and contralateral non-crowded regions (control) of each patient. The presence of 9 periodontopathic species, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Eikenella corrodens, Campylobacter rectus, Capnocytophaga species, Fusobacterium species, Peptostreptococcus micros, Porphyromonas gingivalis, and Bacteroides forsythus, was determined using culture and immunofluorescence techniques. The bacterial morphotype was also determined by the use of dark-field microscopy. It was found that supragingival plaque accumulation in crowded regions was significantly greater than in non-crowded regions. Analysis of the bacteria showed that the samples from crowded regions consistently contained more species of periodontopathogens than the samples from non-crowded regions. Morphologically, more spirochetes and motile rods were present in the crowded-region samples. In terms of the presence of individual periodontopathogens, Fusobacterium species, Capnocytophaga species, C rectus, and P micros were significantly more common in the crowded samples than in the non-crowded samples. It was concluded that: (1) more plaque accumulated in crowded areas; (2) more species of periodontopathogens were present in the subgingival plaque of crowded regions; (3) morphologically, more spirochetes and motile rods were present in crowded areas; and (4) Fusobacterium species, Capnocytophaga species, C rectus, and P micros were present more often in crowded areas than in non-crowded areas (P < 0.05). 相似文献
992.
In vitro selection of mutations in the human immunodeficiency virus type 1 reverse transcriptase that decrease susceptibility to (-)-beta-D-dioxolane-guanosine and suppress resistance to 3'-azido-3'-deoxythymidine 下载免费PDF全文
Bazmi HZ Hammond JL Cavalcanti SC Chu CK Schinazi RF Mellors JW 《Antimicrobial agents and chemotherapy》2000,44(7):1783-1788
993.
AM Havens Y Jung YX Sun J Wang RB Shah HJ Bühring KJ Pienta RS Taichman 《BMC cancer》2006,6(1):195-13
Background
The chemokine stromal derived factor-1 (SDF-1 or CXCL12) and its receptor CXCR4 have been demonstrated to be crucial for the homing of stem cells and prostate cancers to the marrow. While screening prostate cancers for CXCL12-responsive adhesion molecules, we identified CD164 (MGC-24) as a potential regulator of homing. CD164 is known to function as a receptor that regulates stem cell localization to the bone marrow. 相似文献994.
995.
H-cadherin is a newly characterized cadherin molecule whose expression is
decreased in a variety of human carcinoma cells, suggesting that it may
play a role in maintaining normal cellular phenotype. To investigate how
re-expression of H-cadherin could influence the malignant phenotype of
human breast carcinoma cells in vivo, we transfected both control and
H-cadherin expression vectors into human breast cancer cells (MDAMB435),
which do not express H-cadherin constitutively. We found that invasiveness
of these cells could be prevented by transfection with H-cadherin. We also
compared the ability of control- and H-cadherin-transfected cells to induce
subcutaneous tumors after injection into mammary fat pads of nude mice. Our
results show that H-cadherin transfection produced a marked inhibition of
tumor growth and modified the morphology of tumor cells: tumors from mice
injected with control cells were significantly larger and contained larger
cells having a higher degree of pleomorphism than those of tumors generated
from carcinoma cells expressing H-cadherin. Altogether, these results
indicate that H-cadherin expression antagonizes tumor growth in nude mice,
presumably by enhancing cell- cell association in a tissue environment.
These findings strongly suggest that H-cadherin could provide a possible
target for corrective gene therapy against breast cancer.
相似文献
996.
AH Baqui A de Francisco SE Arifeen AK Siddique RB Sack 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(8):863-866
To evaluate the safety of vitamin A supplementation in early infancy using DPT/OPV immunization contracts, a double-blind, randomized, placebo-controlled trial was conducted in Bangladesh. One hundred and sixty-seven infants received three doses of either 25 000 IU of vitamin A or a placebo at about 6.5, 11.8 and 17.0 weeks of age. Trained physicians examined each of the infants on days 1, 2, 3 and 8 after supplementation. Nine infants (10.5%) supplemented with vitamin A had episodes of bulging of the fontanelle compared with two infants (2.5%) in the placebo group (p < 0.05). Twelve of the 14 episodes occurred in infants supplemented with vitamin A. Of these 12 episodes, none occurred with the first dose, 3 occurred with the second and 9 with the third dose. The higher incidence of bulging of the fontanelle in the vitamin A group relative to the placebo group and its temporal association with the vitamin A doses are suggestive of a causal association. The finding that increased numbers of vitamin A doses were associated with a higher probability of bulging of the fontanelle suggests a cumulative effect. Bulging fontanelle, clinical trial, safety, toxicity, vitamin A
AH Baqui, Urban MCH-FP Extension Project, ICDDR.B, GPO Box 128, Dhaka 1000, Bangladesh 相似文献
AH Baqui, Urban MCH-FP Extension Project, ICDDR.B, GPO Box 128, Dhaka 1000, Bangladesh 相似文献
997.
De Michele G Filla A Cavalcanti F Tammaro A Monticelli A Pianese L Di Salle F Perreti A Santoro L Caruso G Cocozza S 《Neurology》2000,54(2):496-499
We describe two sisters with early onset gait ataxia, rapid disease progression, absent or very mild dysarthria and upper limb dysmetria, retained knee jerks in one, slight to moderate peripheral nerve involvement, and diabetes. Molecular analysis showed that they are compound heterozygotes for GAA expansion and a novel exon 5a missense mutation (R165P). This mutation appears to be associated with an atypical but not milder Friedreich ataxia phenotype. 相似文献
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