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91.
The relationship between volatile fatty acids (VFAs) in pus and infecting bacterial species was examined in order to establish a rapid identification system for anaerobic microorganisms in purulent inflammation in the oro-maxillary region. VFAs were detected by the direct injection of pus into gas-liquid chromatography (GLC). Bacterial examination was carried out by anaerobic culture using blood agar plates. The bacterial identification was carried out mainly according to the VPI manual. Analysis of the direct VFA patterns of each sample resulted in 5 groups. The following bacterial species were the main isolates in each group: Streptococcus intermedius in Group A, Peptostreptococcus micros in Group B, Fusobacterium nucleatum in Group C, Bacteroides gingivalis in Group D, and Peptostreptococcus anaerobius in Group E. The profile of VFAs produced in the PYG culture medium of the above isolated bacteria was compared with the direct VFA patterns. Agreement ratios between direct and PYG VFA patterns were as follows: Group A, 47.1%; Groups B and C, 45.0%; Group D, 87.5%; and Group E, 62.9%. The acetic acid concentration was more than 14 x 10(-4) meq/ml in Group B, the butyric acid concentration was more than 7 x 10(-4) meq/ml in Group C, and the iso-caproic acid concentration was more than 14 x 10(-4) meq/ml in Group E. In these cases, it was found that the agreement ratios between the direct and PYG FVA pattern were high. In Group D, irrespective of the concentration of iso-valeric acid detected, the agreement ratio was very high. The antibiotic susceptibility of the isolates was studied. Efficiency rates of ABPC, PIPC, CCL, CEZ, CMZ, SBT/CPZ, JM, CLDM, MINO and GM were relatively low and resistant rates were high for the gram-negative rods.  相似文献   
92.
Zymosan-induced chemiluminescence was investigated in whole blood and in neutrophils: in both, the peak count was frequently elevated in Beh?et's disease, and was significantly higher than in healthy controls; similarly the peak time was shorter. There were more uncommon serotypes of Streptococcus sanguis in the oral flora of patients with Beh?et's disease. Common serotypes were present in the flora of healthy controls, but not in patients with the disease. The percentage of Strep. sanguis in the oral flora was significantly correlated with the level of chemiluminescence response. Thus infection with uncommon serotypes of Strep. sanguis may play a role in the aetiology of Beh?et's disease.  相似文献   
93.
An acyanotic cardiac disease (ASD) was diagnosed in a 9-year-old girl with a very high caries incidence and premature tooth eruption. After the heart operation her caries incidence declined considerably. An epidemiological survey was then conducted to find out if these observations could be generalized. dmf-t, dmfs, DMF-T and DMFS values for each year were counted retrospectively for a group of acyanotic heart diseased children operated on at the age of 5-7 years (mean 6) and another group operated on at the age of 10-13 years (mean 12), from the documents relating to annual examinations conducted by the public health dental services. The results were compared to those of healthy children matched for age and sex living in the same area. Heart disease resulted in DMF-T values above the control level in the group operated on at age 6 years, whereas the values were lower than the controls in the group operated on at age 12 years, the difference being significant after the operation in the latter case. It is concluded that acyanotic congenital heart disease may lead to a higher caries prevalence and sometimes rampant caries. When the caries prevalence of the population is high, however, (DMF-T higher than 4.5 at 12 years), the effect of heart disease remains hidden.  相似文献   
94.
95.
The etiology of a form of periodontal disease in domestic cats known as plasma cell gingivitis-pharyngitis is not understood. Actinobacillus actinomycetemcomitans and Bacteroides species have been strongly implicated as the cause of periodontitis in humans and other mammalian species, and most affected patients manifest serum antibodies reactive with the infecting bacteria. We and others have isolated Bacteroides species from the oral flora of cats. Using enzyme-linked immunosorbent assay (ELISA) and immunoblot procedures, we measured serum antibodies in affected and control cats reactive with human isolates of A. actinomycetemcomitans, B. gingivalis, and B. intermedius, and purified lipopolysaccharide (LPS) from these and other species, and Bacteroides of cat origin. Affected cats had serum antibody titers reactive with these Gram-negative anaerobic bacteria that were significantly elevated relative to those of normal control cats. The quantitatively major antigens recognized by cat serum antibodies are proteins; this contrasts sharply with serum antibodies from humans with juvenile periodontitis, where LPS is the quantitatively major antigen fraction. Our data support the idea that plasma cell gingivitis-pharyngitis in cats may have a bacterial etiology, and that Gram-negative anaerobes similar to those that cause periodontitis in humans and other mammals may be involved.  相似文献   
96.
This study investigated two variables associated with scaling and planning (S&RP): operator experience level and root surface access. One hundred and fourteen periodontally involved, single-rooted teeth designated for extraction were randomly distributed among four operators of various experience levels for either an open or closed session of S&RP. Immediately after treatment, the teeth were extracted, washed, and scored for residual calculus in a blind manner. Results showed that there was no difference in S&RP effectiveness for experience level or type of procedure in shallow (1-3 mm) pockets. However, in moderate (4-6 mm) and deep (greater than 6 mm) periodontal pockets, S&RP combined with an open flap procedure was more effective than S&RP alone for both experience levels. Also, the more experienced operators produced a significantly greater number of calculus-free root surfaces than the less experienced operators in periodontal pockets with moderate and deep probing depths. Clinical application of these results suggests that surgical access is associated with thorough surface debridement in periodontal pockets with moderate-to-advanced probing depths. However, more experienced operators could be expected to render more effective soft surface debridement.  相似文献   
97.
Angiolipoma of the tongue: report of a case   总被引:1,自引:0,他引:1  
Angiolipoma is a rare variety of lipoma in the maxillofacial region. Only eight cases have been documented so far. A case in which an angiolipoma occurred within the tongue of a 49-year-old man is described here. The difference from earlier cases occurring in the tongue is noted. Close follow-up has, as yet, revealed no recurrence.  相似文献   
98.
The inhibitory reflex response evoked by mildly noxious lip stimulation was tested in up to 100 trials at two different levels of pre-stimulus excitation. To regulate that excitation, the subject voluntarily controlled the firing rate of one motor neurone at 10 Hz, and then at 15 Hz while the reflex was tested. When the frequency of the motor-unit action potential (MUAP) in the controlled unit increased or decreased, the frequency of other active units' MUAPs also changed in parallel: that is, the frequency of one MUAP was an index of whole muscle excitation. The inhibitory response in the surface electromyogram (EMG) was quantitated by rectifying and averaging the signal, and by measuring its depth and area. The best correlation between the responses evoked in single units and the response in the whole muscle EMG at the two levels of excitation was obtained when the area of inhibition in the surface record was normalized to the pre-stimulus EMG level. The inhibitory response to lip stimulation in the masseter EMG decreased when the level of pre-stimulus excitation in the muscle was increased. This was confirmed using the reflex response in the averaged force data. The findings suggest that controlling one motor unit's firing rate is a useful method for controlling the whole-muscle excitation in quantitative reflex studies.  相似文献   
99.
We conducted this study to measure maternal plasma, fetal plasma, and fetal enamel fluoride concentrations for four hours following an oral F dose to near-term pregnant guinea pigs. We placed female guinea pigs on de-ionized (Group I) or 3-ppm-F (Group II) drinking water prior to breeding and during gestation. On the 57th day of gestation, we administered a maternal dose of NaF solution (0.6 mg F/kg) by stomach tube. We collected samples of maternal plasma, fetal plasma, and fetal enamel at baseline, at 15 and 30 min, and at one, two, and four h after administration of the dose. We assayed samples for F using a modification of the micro-diffusion and ion-specific electrode method. Group I mean baseline F values were: maternal plasma, 0.016; fetal plasma, 0.002; and fetal enamel, 7.0 ppm. Group II mean values were: 0.055, 0.004, and 19.0 ppm. After the maternal fluoride dose, the mean maternal plasma [F] rose sharply for 30 to 60 min and declined to about 50% of peak values by four h. Fetal plasma [F] changed less in absolute values, but similarly to maternal changes relative to baseline. Fetal enamel mean [F] rose more in Group II than in Group I. Baseline F status had an important effect on F uptake in fetal enamel following an acute maternal fluoride dose.  相似文献   
100.
Oral examinations were performed on 5 patients with hypophosphatemic bone disease (HBD) (2 males and 3 females), 14 patients with X-linked hypophosphatemia (XLH), and 4 affected XLH relatives (6 males and 12 females). The control subjects were the unaffected siblings and parents of the patients and unrelated healthy, gender- and age-matched subjects. Serum phosphorus values were the same by disease type and gender in patients with HBD and XLH. They shared certain dental abnormalities, in particular pulpal necrosis and large pulp spaces. However, only patients with XLH had Class III malocclusions and mild enamel defects, and males with XLH had more severe occlusal and enamel defects than females with XLH. Different dental phenotypes are further evidence that XLH and HBD are different diseases. The dental abnormalities were not prevented by treatment, instituted early in life, which raised serum phosphorus to the near normal range.  相似文献   
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