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601.
602.
Fourteen human periodontal isolates recovered from a purported Eikenella corrodens-selective medium containing 1 microgram of clindamycin per ml displayed biochemical traits which differed from those described for E. corrodens. These organisms were gram-negative rods which corroded agar. The isolates were oxidase positive and urease, indole, and esculin negative. They differed from E. corrodens in catalase, nitrate reduction, lysine decarboxylase, and ornithine decarboxylase activities. One isolate, strain UB-294, was presumptively identified as Kingella denitrificans. A second isolate, strain UB-204, differed from E. corrodens by being catalase positive and nitrate reduction negative. Twelve isolates, including strain UB-38T (T = type strain), were phenotypically similar to Kingella kingae except that they did not produce acid from maltose and were not beta-hemolytic. Essentially complete (1,480-base) 16S rRNA sequences were determined for strains UB-38T, UB-204, and UB-294 and the type strains of Neisseria animalis, Neisseria canis, Neisseria denitrificans, Neisseria elongata, Neisseria flavescens, Neisseria macaca, and Neisseria polysaccharea. These sequences were compared with the previously published sequences of six other species belonging to the family Neisseriaceae. On the basis of the results of the comparative sequence analysis, UB-294 was confirmed as a K. denitrificans strain, UB-204 was identified as a member of a new species which may belong in the genus Eikenella, and UB-38T was identified as a member of a new species of the genus Kingella, for which we propose the name Kingella oralis [corrected]. Since strain UB-204 was the only representative of a new species, it was not named.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
603.
OBJECTIVE: The diagnosis of ganglion cysts of articular origin may sometimes be uncertain when communication with the joint is not evident. Because we have observed that opacification of ganglion cysts revealed by arthrography can be significantly delayed, the purpose of this study was to determine retrospectively in 20 cases the time delay needed to show with arthrography a communication between the articular cavity and ganglion cysts of the knee. CONCLUSION: Arthrographic evidence of a communication between the articular cavity of the knee and communicating ganglion cysts requires delayed radiography performed at least 1 hr after intraarticular injection of contrast material. The best results are obtained with additional CT performed 1-2 hr after injection.  相似文献   
604.
The purpose of this study was to compare an experimental regimen of atovaquone plus proguanil with the standard regimen of quinine plus tetracycline for the treatment of uncomplicated falciparum malaria. The study was designed as an open, randomized study of men presenting with symptoms of uncomplicated malaria and thick-smear slide confirmation of parasitemia (1000-100,000 ring forms/microL). Subjects were hospitalized for 28 days to insure medication compliance and to rule out the possibility of reinfections. With 77 patients in each group, the cure rates were 98.7% and 100% for atovaquone plus proguanil and quinine plus tetracycline, respectively. The parasite clearance times (mean, 56 h) and fever clearance times (mean, 19 h) were significantly shorter in the atovaquone plus proguanil group, and there were significantly fewer side effects in the atovaquone plus proguanil group. Atovaquone plus proguanil is an efficacious, easily administered, safe regimen for the treatment of uncomplicated, multidrug-resistant falciparum malaria in Brazil.  相似文献   
605.
Antibody responses against antibodies, such as rheumatoid factors, are found in several immunopathological diseases and may play a role in disease pathogenesis. Experience shows that they are usually difficult to induce experimentally. Antibodies specific for immunoglobulin constant regions (anti-allotypic) or for variable regions (anti-idiotypic) have been investigated in animal models; the latter have even been postulated to regulate antibody and T cell responses via network-like interactions. Why and how such anti-antibodies are induced during autoimmune diseases, has remained largely unclear. Because repetitively arranged epitopes in a paracrystalline structure of a viral envelope cross-link B cell receptors efficiently to induce a prompt T-independent IgM response, this study used immune complexes containing viruses or bacteria to evaluate the role of antigen pattern for induction of anti-antibody responses. We present evidence that antibodies bound to strictly ordered, but not to irregularly arranged, antigens dramatically enhance induction of anti-antibodies, already after a single immunization and without using adjuvants. The results indicate a novel link between anti-antibody responses and infectious agents, and suggest a similar role for repetitive self-antigens such as DNA or collagen involved in chronic immunopathological diseases.  相似文献   
606.
A prospective study of family history and the risk of colorectal cancer   总被引:1,自引:0,他引:1  
BACKGROUND: A family history of colorectal cancer is recognized as a risk factor for the disease. However, as a result of the retrospective design of prior studies, the strength of this association is uncertain, particularly as it is influenced by characteristics of the person at risk and the affected family members. METHODS: We conducted a prospective study of 32,085 men and 87,031 women who had not previously been examined by colonoscopy or sigmoidoscopy and who provided data on first-degree relatives with colorectal cancer, diet, and other risk factors for the disease. During the follow-up period, colorectal cancer was diagnosed in 148 men and 315 women. RESULTS: The age-adjusted relative risk of colorectal cancer for men and women with affected first-degree relatives, as compared with those without a family history of the disease, was 1.72 (95 percent confidence interval, 1.34 to 2.19). The relative risk among study participants with two or more affected first-degree relatives was 2.75 (95 percent confidence interval, 1.34 to 5.63). For participants under the age of 45 years who had one or more affected first-degree relatives, the relative risk was 5.37 (95 percent confidence interval, 1.98 to 14.6), and the risk decreased with increasing age (P for trend, < 0.001). CONCLUSIONS: A family history of colorectal cancer is associated with an increased risk of the disease, especially among younger people.  相似文献   
607.
608.
BACKGROUND: Concomitant administration of an H1-receptor antagonist with an H2-receptor antagonist may enhance the wheal and flare suppression produced by the H1-antagonist. This synergism may be due, at least in part, to a pharmacokinetic effect. METHODS: In a randomized, double-blind, parallel-group study in 16 patients with chronic urticaria, we investigated the pharmacokinetics and suppressive effect on the histamine-induced wheal and flare of a single dose of hydroxyzine 25 mg or cetirizine 10 mg, given before and after treatment with cimetidine 600 mg every 12 hours for 10 days. RESULTS: When hydroxyzine was administered with cimetidine, the partial hydroxyzine area under the curve increased significantly (p < 0.05) to 303 +/- 92 ng/ml/hr from 227 +/- 77 ng/ml/hr after administration of hydroxyzine alone, and the concentration of cetirizine arising from hydroxyzine was lower. When hydroxyzine was given with cimetidine, wheal and flare suppression increased compared with when hydrozyzine was given alone, but the differences were not statistically significant (p > 0.05). When cetirizine was administered with cimetidine, the pharmacokinetics of cetirizine did not change significantly, and no enhancement of wheal and flare suppression was observed. CONCLUSIONS: In this study co-administration of hydroxyzine with cimetidine resulted in significantly increased serum hydroxyzine concentrations and increased wheal and flare suppression, thus confirming the rationale for a trial of concomitant administration of these medications in some patients with chronic urticaria unresponsive to treatment with an H1-antagonist alone. We found no therapeutic rationale for co-administration of cetirizine with cimetidine in urticaria treatment. These medications may be co-administered safely without fear of medication interaction.  相似文献   
609.
Strains of Bacillus subtilis 168 lysogenic for bacteriophage phi105 transfer with deoxyribonucleic acid (DNA) isolated from bacteriophage SPO2 at a higher efficiency than non-lysogenic strains. This enhancement of transfection was not the result of recombination between bacteriophages SPO2 and phi105. Superinfection marker rescue increased transfection with DNA from bacteriophage phi105 occurred simultaneously with the addition of the transfecting DNA. Again, this enhancement of transfection was not the result of recombination but rather a protection of the transfecting DNA by the superinfecting bacteriophage. The ability of the superinfecting bacteriophage to protect the transfecting DNA from inactivation was maximal when the bacteria were just becoming competent. Bacteriophage phi1 cannot replicate after the transfection of competent bacteria lacking a functional DNA replication system, whereas bacteriophage phi1 was able to replicate after infection of competent bacteria grown under comparable conditions. These observations support the hypothesis that GAPase and an inducible repair system play an important role in the development of competence.  相似文献   
610.
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