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1.
Abstract Several previous studies have evaluated the effects of 0.12% chlorhexidine digluconate (ChD) mouthrinses on plaque and gingival inflammation. However, previously, none have been based in general dental practices. The aim of this study was to evaluate the potential to conduct controlled periodontal clinical trials in co-operation with general dental practitioners (gdps). The project took place in 5 general dental practices in the South of England. 121 healthy subjects (24 at 4 sites and 25 at the 5th). aged 18-65 years, mean 35 ± 12) years participated in a double-blind, randomised study during which they received full mouth assessments for plaque and gingival bleeding at baseline, 6 and 12 weeks. 60 subjects were randomly asigned to use the 0.12% ChD mouth wash and 6i the placebo. The assessments were carried out by 5 gpds, who had previously achieved inter-examiner κ scores of 0.78–0.85 (mean 0.81) for the plaque index (PlI), and of 0.73–0.94 (mean 0.87) for a modified gingival index (mGI), and who maintained κ scores of 0.51–0.90 for PII and of 0.73–1.00 for mGI during the 12 months required to complete the study. 98 subjects (48 ChD and 50 placebo) completed the study. Even though the baseline levels of plaque and gingivitis were low, by week 12, mean whole mouth piaque score of the ChD mouthwash users had fallen from 1.33 at baseline to 0.96 and was significantly lower (p < 0.001) than for the placebo users, 1.31 at baseline to 1.13. Whole-mouth gingival bleeding score fell from 0.56 to 0.42 in the ChD mouthwash group but was unchanged (0.54–0.55) in the placebo group. A subsidiary data analysis which considered the effects at sites indicated that within these overall differences, the ChD users experienced almost 2× the reduction from plaque score 2 at baseline at proximal molar sites over a 12-week period (50.6% ChD versus 27.6% placebo). It was concluded that 0.12% ChD mouthwash reduced plaque accumulation fay 28% and gingival inflammation by 25% over a 12–week period, that it is feasible for a group of gdps to maintain high levels of inter–examiner consistency in the use of PlI and mGI, that it is also feasible to carry out such a multicentre study in general dental practice, and that the use of mean mouth scores per subject to analyse the effects of mouthrinses may well mask variations in response throughout the mouth.  相似文献   
2.
Background: The Centers for Disease Control and Prevention is incorporating laboratory data into real-time surveillance systems. When normal patterns of laboratory test orders and results are modeled, aberrations can be detected. Because many test orders are available electronically well before results, atypical patterns of test ordering may signal outbreaks.
Objectives: The authors sought to characterize baseline patterns in the ordering and early results of lumbar punctures, motivated by the possibility of using these data for real-time surveillance for early detection of meningitis or encephalitis outbreaks.
Methods: Retrospective cohorts of pediatric emergency department patients at a single hospital (1993–2003) and from the National Hospital and Ambulatory Medical Care Survey (1992–2000) were used for analysis.
Results: Test ordering exhibits seasonal patterns, with monthly peaks in January and August (p < 0.0001). For the hospital cohort, the rate of cerebrospinal fluid pleocytosis exhibits seasonal patterns (p < 0.0001), with a peak from August to October. This is strongly associated with the rate and pattern of clinical neurologic disease (p < 0.0001). A long-term secular decline in daily test ordering is evident, dropping from 5.3 to 2.9 in the hospital sample, and from 371.8 to 185.3 in the national sample (p < 0.001). The long-term rate of pleocytosis has declined (p < 0.0001), though the yield of testing for pleocytosis has improved (p = 0.0104).
Conclusions: Laboratory test patterns correspond with those of clinical disease and are a promising source of surveillance data. Using such data for real-time monitoring requires specific adjustments for patient age, periodicities, and secular trends.  相似文献   
3.
OBJECTIVE: To indicate whether the double peaked N(1) to gaps in continuous white noise is a composite of onset and offset responses to transients or whether it reflects higher processing such as change or mismatch detection and to assess the role of attention in this process. METHODS: Evoked potentials were recorded to two binaural stimulus types: (1) gaps of different durations randomly distributed in continuous white noise; and (2) click pairs at intervals identical to those between gap onsets and offsets in the continuous noise stimulus. Potentials to these stimuli were recorded while subjects read a text and while detecting gaps in noise or click pairs. RESULTS: Potentials were detected to all click pairs and to gaps of 5 ms or longer, corresponding to the subjects' psychoacoustic gap detection threshold. With long gap durations of 200-800 ms, distinct potentials to gap onset and gap offset were observed. The waveforms to all click pairs and to offsets of long gaps were similar and single-peaked, while potentials to gaps of 10 ms and longer, and potentials to onsets of long gaps were double-peaked, consisting of two N(1) negativities, 60 ms apart, irrespective of gap duration. The first (N(1a)), was more frontal in its distribution and similar to that of clicks. The second (N(1b)) peak's distribution was more central/temporal and its source locations and time course of activity were distinct. No effects of attention on any of the varieties and constituents of N(1) were observed. CONCLUSIONS: Comparing potentials to gap onsets, to click pairs and to gap offsets, suggests that potentials to gap onsets involve not only sound onset/offset responses (N(1), N(1a)) but also the subsequent pre-attentive perception of the cessation of an ongoing sound (N(1b)). We propose that N(1b) is distinct from change or mismatch detection and is associated with termination of an ongoing continuous stimulus. We propose to call it the N(egation)-process. SIGNIFICANCE: A constituent of the N(1) complex is shown to be associated with the pre-attentive perception of termination of an ongoing stimulus and to have distinct scalp distribution and intracranial sources.  相似文献   
4.
5.
Elevation of the environmental temperature appeared to counteract the temperature-depressing effects of urethane anesthetic and allowed rabbits intracisternally infected with Haemophilus influenzae type b to mimic the development of a fever following infection. Elevated core body temperature (greater than 39 degrees C) was associated with an inhibition of the growth of H. influenzae in cerebrospinal fluid (CSF) during the first 12 h postinfection, whereas bacterial growth was essentially unrestricted in rabbits with reduced (approximately 37 degrees C) body temperature. Bacterial densities 24 h postinfection were different, hyperthermic animals having log 6.0 +/- 0.4 CFU/ml of CSF and hypothermic rabbits having log 8.2 +/- 0.8 CFU/ml of CSF (P less than 0.05, Wilcoxon rank sum test). However, the growth of this bacterium in vitro, in either pooled rabbit CSF or brain heart infusion broth, was not inhibited at 39 degrees C. These results suggest that elevated body temperature associated with the development of fever during meningitis may be associated with restriction of the growth of H. influenzae in vivo but that this effect is apparently not due to an innate inability of the bacterium to grow at elevated temperatures.  相似文献   
6.
Older age, prior transplantation, pulmonary hypertension, and mechanical support are commonly seen in current potential cardiac transplant recipients. Transplants in 436 consecutive adult patients from 1994 to 1999 were reviewed. There were 251 using standard donors in 243 patients (age range 18-69 years). To emphasize recipient risk, 185 patients who received a nonstandard donor were excluded from analysis. The indications for transplant were ischemic heart disease (n = 123, 47%), dilated cardiomyopathy (n = 82, 32%), and others (n=56, 21%). One hundred and forty-nine (57%) recipients were listed as status I; 5 and 6% were supported with an intra-aortic balloon and an assist device, respectively. The 30-d survival and survival to discharge were 94.7 and 92.7%, respectively; 1-year survival was 89.1%. Causes of early death were graft failure (n = 6), infection (n = 4), stroke (n = 4), multiorgan failure (n = 3) and rejection (n = 2). Predictors were balloon pump use alone (OR= 11.4, p =0.002), pulmonary vascular resistance > 4 Wood units (OR = 5.7, p = 0.007), pretransplant creatinine > 2.0 mg/dL (OR = 6.9, p = 0.004) and female donor (OR = 8.3, p = 0.002). Recipient age and previous surgery did not affect short-term survival. Heart transplantation in the current era consistently offers excellent early and 1-year survival for well-selected recipients receiving standard donors. Early mortality tends to reflect graft failure while hospital mortality may be more indicative of recipient selection.  相似文献   
7.
Diagnostic value of citrate agar electrophoresis. Am J Clin Pathol 71:668-671, 1979. Of approximately three dozen hemoglobin variants that have greater than usual oxygen affinity, nearly half are inseparable from hemoglobin A by electrophoresis at pH 8.6. A comparison of hemoglobins Wood (alpha2beta297leu) and Malm? (alpha2beta297gln) is of interest from several standpoints. They represent similar substitutions at the identical locus in the beta chain. They result in identical clinical and hematologic manifestations. Oxygen affinities of these variants are identical. Both are poorly resolved from hemoglobin A by electrophoresis at pH 8.6. The position of each is identical when studied by isoelectric focusing in polyacrylamide gel. Finally, they are easily distinguished by citrate agar electrophoresis at pH 6.2. The excellent resolution of hemoglobins Malm? and Wood from each other results neither from difference in charge, nor size, nor in quaternary structure. This technic provides a simple but effective means for identifying and differentiating these hemoglobin variants. Comparison with the results of citrate agar electrophoresis of other high oxygen-affinity hemoglobins indicates that the findings for hemoglobins Malm? and Wood are unique and unambiguous.  相似文献   
8.
The virulence of Haemophilus influenzae type c when inoculated intracisternally (i.c.) into rabbits was evaluated. Rabbits are relatively resistant to infection with H. influenzae type b, such that inocula of the order of 10(6-9) cfu are required to produce meningitis in this model. In contrast, fatal meningitis was produced in this study when 10(3) cfu of a type-c strain were injected i.c. into rabbits. Numbers of bacteria in cerebrospinal fluid (CSF) of control (untreated) animals generally increased to 10(7) cfu/ml. Increases in white blood cells, protein and lactate in the CSF were similar to those which had been observed during meningitis due to Streptococcus pneumoniae in rabbits. The infection was amenable to therapy with ampicillin 50 mg/kg given intravenously 12 h after infection. Numbers of bacteria in CSF were reduced to 2.2 x 10(3) cfu/ml (SEM 0.2 x 10(3)) at 8 h after treatment with a single dose of ampicillin. Two doses of ampicillin, given 12 and 20 h after infection, significantly increased the mean survival time. In contrast to previous experimental studies with rabbits, the penetration of ampicillin into the CSF was high--46 (SEM 10) % of the blood level. Since considerable replication of H. influenzae type c occurred within the CSF in this model, the nature of the meningeal damage produced was likely to be similar to that which takes place in man. Hence, H. influenzae type c meningitis in rabbits may provide a useful model in which therapeutic and other experimental studies of H. influenzae meningitis can be performed.  相似文献   
9.
Pentastomiasis: case report of an acute abdominal emergency   总被引:3,自引:0,他引:3  
U Herzog  P Marty  F Zak 《Acta tropica》1985,42(3):261-271
A 34-year-old native women presented as an acute abdominal emergency at the Surgery Department, Missionary Hospital "Ad Lucem" in Banka-Bafang, Cameroon. She complained of colicky, epigastric abdominal pain, nausea, vomiting, constipation, and retention of flatus. At laparotomy, numerous small cystic nodules (3-8 mm in diameter) were noted in the mesentery and under the intestinal and parietal peritoneum. Histological examination of two of them revealed slightly enlarged mesenteric lymph nodes containing several parasitic pseudocysts. The parasites were diagnosed as well-preserved, encysted, Armillifer armillatus nymphs. Neither degenerative nor inflammatory granulomatous reactions were observed in the adjacent tissue. Two and a half years later, a similar attack of acute abdominal symptoms recurred. A radiological examination revealed several C-shaped or circular, dense opacities characteristic of calcified pentastomid nymphs. At laparotomy, local findings similar to those at the previous surgical examination were noted. Additionally, a few firm, whitish, calcified nodules were found in the mesentery and under the fibrous capsule of the liver.  相似文献   
10.
BackgroundIntraoperative tourniquet use in total knee arthroplasty (TKA) is a common practice which may improve visualization of the surgical field and reduce blood loss. However, the safety and efficacy associated with tourniquet use continues to be a subject of debate among orthopedic surgeons. The primary purpose of this study is to evaluate the effects of tourniquet use on pain and opioid consumption after TKA.MethodsThis is a multicenter randomized controlled trial among patients undergoing TKA. Patients were preoperatively randomized to undergo TKA with or without the use of an intraoperative tourniquet. Frequency distributions, means, and standard deviations were used to describe baseline patient demographics (age, gender, race, body mass index, smoking status), length of stay, surgical factors, visual analog scale pain scores, and opioid consumption in morphine milligram equivalents.ResultsA total of 327 patients were included in this study, with 166 patients undergoing TKA without a tourniquet and 161 patients with a tourniquet. A statistically significant difference was found in surgical time (97.87 vs 92.98 minutes; P = .05), whereas none was found for length of stay (1.73 vs 1.70 days; P = .87), postop visual analog scale pain scores (1.73 vs 1.70; P = .87), inpatient opioid consumption (19.84 vs 19.27 morphine milligram equivalents; P = .74), or outpatient opioid consumption between the tourniquet-less and tourniquet cohorts, respectively. There were no readmissions in either cohort during the 90-day episode of care.ConclusionUtilization of a tourniquet during TKA has minimal impact on postoperative pain scores and opioid consumption when compared with patients who underwent TKA without a tourniquet.  相似文献   
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