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81.
Two methods of staining (Papanicolaou versus direct immunofluorescence) and two methods of collection of the samples (Ayre's wooden spatula versus cervical Cytobrush) were compared in order to verify the efficiency in detecting Chlamydia trachomatis (CT) infections in the female genital tract. Out of 166 asymptomatic patients, 59 were positive for CT by means of direct immunofluorescence: 36 were detected in Cytobrush samples, 16 in Ayre's spatula samples, and 7 in the samples collected by both methods. Papanicolaou smears showed "moth-eaten" features suggestive of CT infection in a great number of metaplastic cells present in 35 cases: 24 collected by Cytobrush, 4 by Ayre's spatula and 7 by both methods. Our data show that Cytobrush is more efficient that Ayre's spatula in concentrating cellular material. It is thus possible to detect CT infection with more accuracy by means of direct immunofluorescence, and to suspect CT infection in smears collected by means of Cytobrush and stained by Papanicolaou's method.  相似文献   
82.
The present study evaluated the skeletal alterations induced by rapid maxillary expansion procedures in 30 patients in the primary and mixed dentitions. The results were obtained with the use of lateral cephalometrics before and immediately after the active phase of expansion. The time span between these two cephalometric films ranged from 14 to 21 days; therefore the "growth factor" was not considered. Based on the differences in the cephalometric measurements studied on the first and second tracings, it seems that anterior displacement of the maxilla with significant changes in the SNA angle should not be expected, although point B was repositioned more posteriorly (SNB) because of the mandibular downward and backward rotation, with subsequent increase of the inclination of the mandibular plane. The alterations in the A-P position of the mandible was reflected in the increase of ANB and NAP angles. The maxilla always dislocates downward, displaying a downward and backward rotation in the palatine plane, significantly altering the following measurements: N-ANS, PNS-PNS', A-A', SN.PP. The anchoring molars also follow the downward maxillary displacement (M-M') and, as a direct consequence of the vertical displacement of the maxilla and upper molars (N-ANS, A-A', ANS-Me, N-Me, PNS-PNS'), the facial heights increase.  相似文献   
83.
We are concerned in this paper with learning classification procedures from known cases. More precisely, we provide a diagnostic model that discriminate between cerebellum-pontine angle (CPA) tumors and otorhinolaryngological (ENT) disorders. Usually, in order to distinguish between CPA tumors and ENT disorders one must perform clinical-neurological examination together with expensive radiological imagery (CT and MRI). The proposed model was obtained through artificial intelligence methods and presented a good accuracy level (88.4%) when tested against new cases, considering only clinical examination without radiological imagery results.  相似文献   
84.
We report the association a multiple sclerosis (MS), spinal cord tumour and intracranial tumor in a 63 years-old female patient with a 10 years history of relapsing/remitting MS. Symptoms usually remitted in response to costicosteroid therapy. In 1997 the patient presented with paraparesis and paresis of right arm which did not respond to corticotherapy. A spinal RMI revealed in the cervical spinal an intra spinal cord tumour, further diagnosed as ependymoma, and a parietal region meningioma. We call attention to this rare association of central nervous system tumour and MS, enphasizing the need for investigation of new and uncommon symptoms during the evolution of MS.  相似文献   
85.
In order to obtain basic data on the effect of broad-spectrum protease inhibitor against local symptoms of Viperidae snake envenomation, inhibitory capacity of rat murinoglobulin on local hemorrhagic and edematogenic activities of venoms from Crotalus atrox, Bothrops jararaca, Lachesis muta muta, Trimeresurus flavoviridis and Echis carinatus sochureki were examined. Murinoglobulin, pre-incubated with the crude venoms at 37 degrees C for 15 min, inhibited hemorrhagic activity of all five venoms to various extents. The activity of C. atrox was almost completely inhibited at the murinoglobulin/venom ratio (w/w) of 20. The activity of B. jararaca, Lachesis muta muta and T. flavoviridis venoms was considerably inhibited at the ratio of 20 (77.2, 80.0 and 86.2% inhibition, respectively), however some of the activity still remained even at the ratio of 40 (84.2, 79.8 and 86.2% inhibition, respectively). Among the five venoms, E. c. sochureki venom is quite resistant to murinoglobulin treatment and statistically significant inhibition was only found at the ratio of 40 (64.1% inhibition). Fibrinolytic and gelatinase activities were more susceptible to murinoglobulin inhibition. The treatment at the ratios of 10 and 20 almost completely inhibited respectively the fibrinolytic and the gelatinase activities of all the venoms. Murinoglobulin treatment also significantly inhibited the edematogenic activity of L. muta muta, T. flavoviridis and Echis carinatus sochureki. The treatment of murinoglobulin at the ratio of 40 considerably suppressed the swelling up to 60 min after subcutaneous injection of L. muta muta and E. c. sochureki venoms, and up to 30 min after T. flavoviridis venom injection. Murinoglobulin is a potent inhibitor against local effects of multiple snake venoms in Viperidae family.  相似文献   
86.
Tissue lesion mechanisms provoked by sepsis include the infectious process, inflammation, and cellular energy deficit. We chose to test fructose-1,6-bisphosphate (FBP) because of its possible anti-inflammatory and antimicrobial actions. Wistar rats were used and divided into three experimental groups: a control group (n=10), in which a capsule was introduced into the peritoneum of the animals; a septic group (n=10), in which a capsule containing non-sterile fecal matter was introduced together with Escherichia coli (1.5 x 10(9)CFU); and a septic group treated with FBP 500 mg/kg (n=10). The blood cell tests revealed that levels of leukocytes increased significantly in the septic group when compared to both the septic group treated with FBP and the control group. The blood cultures were 100% positive in both the septic group and the septic group treated with bisphosphorylated sugar. The antibiogram only revealed an inhibitory halo in the case of the antibiotic ampicillin, there was no such indication for FBP. The anti-inflammatory power of FBP remained at 60% for 5 h in the rats that received the carrageenan injection. What is more, the sugar reduced the levels of ionic calcium in relation to the control group. This data proves the validity of using FBP in the treatment of sepsis, possibly due to its anti-inflammatory rather than antimicrobial action.  相似文献   
87.
PURPOSE: To compare the effectiveness and side effects of methadone and morphine as first-line treatment with opioids for cancer pain. PATIENTS AND METHODS: Patients in international palliative care clinics with pain requiring initiation of strong opioids were randomly assigned to receive methadone (7.5 mg orally every 12 hours and 5 mg every 4 hours as needed) or morphine (15 mg sustained release every 12 hours and 5 mg every 4 hours as needed). The study duration was 4 weeks. RESULTS: A total of 103 patients were randomly assigned to treatment (49 in the methadone group and 54 in the morphine group). The groups had similar baseline scores for pain, sedation, nausea, confusion, and constipation. Patients receiving methadone had more opioid-related drop-outs (11 of 49; 22%) than those receiving morphine (three of 54; 6%; P =.019). The opioid escalation index at days 14 and 28 was similar between the two groups. More than three fourths of patients in each group reported a 20% or more reduction in pain intensity by day 8. The proportion of patients with a 20% or more improvement in pain at 4 weeks in the methadone group was 0.49 (95% CI, 0.34 to 0.64) and was similar in the morphine group (0.56; 95% CI, 0.41 to 0.70). The rates of patient-reported global benefit were nearly identical to the pain response rates and did not differ between the treatment groups. CONCLUSION: Methadone did not produce superior analgesic efficiency or overall tolerability at 4 weeks compared with morphine as a first-line strong opioid for the treatment of cancer pain.  相似文献   
88.
The international decline in gastric cancer is mainly attributed to improved socio-economic conditions. However, some southern and eastern European countries showed slower and later decline, reflecting a less favourable general environment The same probably applies to regional differences within countries, making national indicators potentially misleading. Fitting log-linear Poisson models we compared trends in gastric cancer mortality (1984-1999) across 18 Portuguese regions. Pearson correlation coefficients were computed to assess the regional association between decline in cancer mortality and baseline cancer mortality and variation in indices of social development and medical care. National gastric cancer mortality changed -2.0% year in men and -2.2% year in women. The regional yearly variation in mortality ranged from -3.5% [95% confidence interval (CI) -4.5 to -2.5] to -0.6% (95% CI -1.4 to 0.2) in men, and from -3.7% (95% CI -4.8 to -2.7) to -0.8% (95% CI -1.6 to 0.0) in women. Regional variation was not significantly associated with baseline gastric cancer mortality (r = 0.18, P = 0.47), but with the variation in post-neonatal mortality (r = 0.59, P = 0.01). In Portugal, gastric cancer shows a wide regional variation in frequency trends. The correlation with known indicators of social and economic development indicates that future improvement in gastric cancer rates is expected in parallel with a more widespread development.  相似文献   
89.
OBJECTIVE: To estimate the frequency of modifiable cardiovascular risk factors, with and without inclusion of arterial hypertension, occurring simultaneously in a racially-mixed population. METHOD: A cross-sectional study was carried out with 1,298 adults aged > or = 20 years in the city of Salvador, Brazil, in 2000. Eight modifiable cardiovascular risk factors were assessed, in any combination: total cholesterol > or = 240 mg/dL; high density-lipoprotein cholesterol (HDL-c) < 40 mg/dL; triglycerides > or = 200 mg/dL; glycemia > or = 126 mg/dL + well-controlled diabetes; body mass index > or = 25 kg/m2, waist > or = 102 cm for males and > or = 88 cm for females, smoking and alcoholism. The results were stratified according to the number of simultaneous risk factors (zero to five or more and two or more risk factors). The data were analyzed in terms of estimated proportions and 95% confidence intervals (95%CI), with and without the inclusion of arterial hypertension (VI Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure [JNC-VI], United States of America), ratio of proportions and chi-square for proportions as a measure of association. RESULTS: Among men (41.4% of participants), 7.5% (95%CI: 2.5 to 9.7) did not present risk factors; 68.8% (95%CI: 65.0 to 72.8) presented two or more risk factors, not including hypertension. After inclusion of hypertension, 73.4% (95%CI: 69.7 to 77.1) presented two or more risk factors. Among women, 11.6% did not present risk factors. The presence of two or more risk factors, not including hypertension, was observed in 67.7% (95%CI: 64.8 to 71.4). After inclusion of hypertension, 71.7% (95%CI: 68.5 to 74.9) of the women presented two or more risk factors. Significant differences were observed for the presence of two or more risk factors in men with not more than 4 years of schooling vs. 5 to less than 11 years of schooling (P < 0.05); in women with not more than 4 years of schooling vs. 5 to less than 11 years of schooling; in women with not more than 4 years of schooling vs. 11 or more years of schooling (P < 0.01); and in black vs. white women (P < 0.01). CONCLUSIONS: The high proportion of clustering cardiovascular risk factors in Salvador, with or without hypertension, especially in the population with little schooling and in black individuals, suggests the need for broad social strategies to reduce social inequality, promote health, and facilitate the treatment of cardiovascular risk factors.  相似文献   
90.
OBJECTIVE: To examine the impact of different social, familial, and behavioral factors on the risk of developing obesity in adolescents. METHODS: We performed a case-control study nested in a population-based cohort that was followed from birth in 1982. Cases were adolescents with obesity, as defined by the World Health Organization. Controls came from a randomly chosen sample of members of the cohort, examined in 1997 and 1998. Information concerning risk factors was obtained from cohort records that were collected at different ages. Multivariate analysis was carried out using logistic regression. RESULTS: Risk factors varied according to sex. Among boys, a family income at birth above one minimum wage was associated with a six-fold increase in obesity, and the presence of trait anxiety in adolescence with a four-fold increase. In both sexes, a one-unit increase in pre-pregnancy maternal body mass index was associated with a 10% increase in obesity. Smoking, fat consumption, time spent watching television or performing physical activity, and concurrent maternal weight were not associated with obesity. CONCLUSIONS: Our results show that it is important to stratify data from obesity studies according to sex. In addition, early-life factors were more strongly associated with obesity than factors present during adolescence. However, the possibility of reporting bias cannot be ruled out, especially in terms of the information provided on diet and physical exercise. Whenever possible, the study of concurrent risk factors for obesity in adolescence should take into account the confounding effect of early-life factors.  相似文献   
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