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991.
The purpose of this continuing longitudinal investigation was to study the changes on the craniofacial complex in complete denture wearers; herein are reported the 20-year findings. At the onset of the study complete dentures were made for 64 persons. Two dentures techniques were employed: a complex method of construction and a simplified method. At the start of the project the patients' ages ranged from 30 to 60 years (average age 53 years) and all had been edentulous for at least 1 year (range 1 to 30 years). Lateral cephalometric radiographs were made immediately after initial placement of the dentures and during subsequent years (1, 2, 3, 4, 5, 7, 10, 15, and 20). The same cephalostat was used throughout and all films were exposed with the teeth in centric occlusion. Thirty-four subjects presented for the 20-year follow-up. Of this number, the radiographs of 24 subjects (14 women and 10 men; average age 65.5 years [range 50-83 years]) (12 complex denture wearers; 12 simplified technique denture wearers) were used in this report (10 had denture alterations over the 20-year period that excluded them). The 20-year observations corroborate earlier findings. There is a loss of the vertical dimension of occlusion as viewed from the right profile, and the mandible rotates in a counterclockwise fashion resulting in an increase in relative prognathism. The maxillary alveolus was stable, the mandibular alveolus resorbed, and the dentures rotated counterclockwise and shifted slightly forward. The observed changes were not significantly affected by the sex of the patient or by the denture technique employed.  相似文献   
992.
993.
Impaired gut mucosal perfusion has been reported during cardiopulmonary bypass. To better define the adequacy of gut blood flow and oxygenation during cardiopulmonary bypass, we measured overall gut blood flow and ileal mucosal flow and their relationship to mucosal pH, mesenteric oxygen delivery and oxygen consumption in immature pigs (n = 8). Normothermic, noncross-clamped, right atrium-to-aorta cardiopulmonary bypass was maintained at 100 ml/kg per minute for 120 minutes. Animals were instrumented with an ultrasonic Doppler flow probe on the superior mesenteric artery, a mucosal laser Doppler flow probe in the ileum, and pH tonometers in the stomach, ileum, and rectum. Radioactive microspheres were injected before and at 5, 60, and 120 minutes of cardiopulmonary bypass for tissue blood flow measurements. Overall gut blood flow significantly increased during cardiopulmonary bypass as evidenced by increases in superior mesenteric arterial flow to 134.1% +/- 8.0%, 137.1% +/- 7.5%, 130.3% +/- 11.2%, and 130.2% +/- 12.7% of baseline values at 30, 60, 90, and 120 minutes of bypass, respectively. Conversely, ileal mucosal blood flow significantly decreased to 53.6% +/- 6.4%, 49.5% +/- 6.8%, 58.9% +/- 11.6%, and 47.8% +/- 10.0% of baseline values, respectively. Blood flow measured with microspheres was significantly increased to proximal portions of the gut, duodenum and jejunum, during cardiopulmonary bypass, whereas blood flow to distal portions, ileum and colon, was unchanged. Gut mucosal pH decreased progressively during cardiopulmonary bypass and paralleled the decrease in ileal mucosal blood flow. Mesenteric oxygen delivery decreased significantly from 67.0 +/- 10.0 ml/min per square meter at baseline to 42.4 +/- 4.6, 44.9 +/- 3.5, 46.0 +/- 3.6, and 42.9 +/- 3.9 ml/min per square meter at 30, 60, 90, and 120 minutes of bypass. Despite the decrease in mesenteric oxygen delivery, mesenteric oxygen consumption increased progressively from 10.8 +/- 1.4 ml/min per square meter at baseline to 13.4 +/- 1.2, 15.9 +/- 1.2, 16.7 +/- 1.4, and 16.6 +/- 1.54 ml/min per square meter, respectively. We conclude that gut mucosal ischemia during normothermic cardiopulmonary bypass results from a combination of redistribution of blood flow away from mucosa and an increased oxygen demand.  相似文献   
994.
995.
Early passive case finding and treatment compliance are the cornerstones of tuberculosis (TB) control programs. As human behavior plays a critical role in both strategies, a better understanding of it is important for the planning and implementation of a successful TB programme, especially for the health education component, Our qualitative study in Uasin Gishu, Kenya, aimed at a better understanding of the community's beliefs and perceptions of TB, recognition of early symptoms and health-seeking behavior. Five focus groups with a total of 49 people were held: on with hospitalized TB patients, two with rural and two with urban participants. Tuberculosis is well known in the communities and many vernacular names for the disease exist. TB is perceived as a contagious, 'sensitive' disease difficult to diagnose and treat. Community members believe that TB should be diagnosed and treated in a hospital or by a medical doctor and not at the peripheric level. TB treatment is perceived as long, agonising and cumbersome. Traditional treatment is considered a valid alternative to modern treatment, believed to be as effective and much shorter. Initial symptoms such as cough and fever are often overlooked and/or confused with malaria or a common cold. Symptoms associated with the disease refer to the later stage of TB. TB is attributed to causes such as smoking, alcohol, hard work, exposure to cold and sharing with TB patients. Many participants believe TB is hereditary. Prolonged self-treatment and consultation with the traditional health sector as well as the social stigma attached to the disease increase patient's delay. Only after symptoms persist for some time and/or the suspect's health deteriorates, are modern health services consulted. These social conditions necessitate culturally sensitive health education, taking into account local perceptions of TB.  相似文献   
996.
997.
CONTEXT: Time to development of acquired immunodeficiency syndrome (AIDS) and time to death have been extended with the increased use of combination therapy and protease inhibitors. Cohort studies following up persons with human immunodeficiency virus (HIV) infection in periods characterized by different therapies offer the opportunity to estimate therapy effectiveness at the population level. OBJECTIVE: To assess the effectiveness of self-reported, long-term potent antiretroviral therapy in a cohort of 536 men whose duration of HIV infection was known (seroconverters). DESIGN: Cohort study. The cohort was compared for time to development of AIDS and time to death in 1984 to 1990, 1990 to 1993, 1993 to July 1995, and July 1995 to July 1997 when the major treatments were no therapy, monotherapy, combined therapy, and potent antiretroviral therapy, respectively. Survival analysis methods with time zero set as the date of seroconversion and incorporating staggered entries into each period were used. Mean CD4 cell change, stratified by infection duration, was determined for each period using a random effects model. SETTING: The Multicenter AIDS Cohort Study (MACS) in 4 urban areas (Baltimore, Md; Chicago, III; Los Angeles, Calif; and Pittsburgh, Pa). PARTICIPANTS: A total of 5622 men who were 18 years or older were enrolled into MACS. Of the 5622, there were 2191 HIV-positive individuals at enrollment. Of the 3431 men who were HIV-negative, 536 were observed to seroconvert and were followed up for up to 13 years. The group of 536 who seroconverted constituted the study population. MAIN OUTCOME MEASURES: Time from seroconversion to development of AIDS and to death and change in CD4 cell count. RESULTS: A total of 231 seroconverters developed AIDS, and 200 men died. Using 1990 to 1993 as the reference period, the relative hazard of AIDS was 1.04 (95% confidence interval [CI], 0.73-1.48) during 1993 to July 1995 and 0.35 (95% CI, 0.20-0.61) during July 1995 to July 1997. Relative hazards of death were 0.87 (95% CI, 0.58-1.31) and 0.62 (95% CI, 0.38-1.01 ) for the same periods. The relative time (the factor by which times are contracted or expanded) to development of AIDS was 0.97 (95% CI, 0.86-1.09) for 1993 to July 1995 and 1.63 (95% CI, 1.40-1.89) for July 1995 to July 1997. Relative survival time for 1993 to July 1995 was 1.01 (95% CI, 0.91-1.12) and for July 1995 to July 1997 was 1.21 (95% CI, 1.07-1.36) relative to 1990 to 1993. The rate of CD4 cell count decline in July 1995 to July 1997 was significantly lower (P<.05) compared with the previous 2 periods. CONCLUSIONS: In the calendar period when potent antiretroviral therapy was introduced, the time to development of AIDS and time to death were extended, and rate of CD4 cell count decline was arrested.  相似文献   
998.
BACKGROUND: Developmental dyslexia is a specific disorder of reading and spelling that affects 3-9% of school-age children and adults. Contrary to the view that it results solely from deficits in processes specific to linguistic analysis, current research has shown that deficits in more basic auditory or visual skills may contribute to the reading difficulties of dyslexic individuals. These might also have a crucial role in the development of normal reading skills. Evidence for visual deficits in dyslexia is usually found only with dynamic and not static stimuli, implicating the magnocellular pathway or dorsal visual stream as the cellular locus responsible. Studies of such a dissociation between the processing of dynamic and static auditory stimuli have not been reported previously. RESULTS: We show that dyslexic individuals are less sensitive both to particular rates of auditory frequency modulation (2 Hz and 40 Hz but not 240 Hz) and to dynamic visual-motion stimuli. There were high correlations, for both dyslexic and normal readers, between their sensitivity to the dynamic auditory and visual stimuli. Nonword reading, a measure of phonological awareness believed crucial to reading development, was also found to be related to these sensory measures. CONCLUSIONS: These results further implicate neuronal mechanisms that are specialised for detecting stimulus timing and change as being dysfunctional in many dyslexic individuals. The dissociation observed in the performance of dyslexic individuals on different auditory tasks suggests a sub-modality division similar to that already described in the visual system. These dynamic tests may provide a non-linguistic means of identifying children at risk of reading failure.  相似文献   
999.
Recent data have suggested enhanced therapeutic activity with prolonged administration of both etoposide as well as fluoropyrimidines in the treatment of gastrointestinal malignancies. Based on this rationale, we investigated the clinical effectiveness and tolerance of an oral modification of the widely applied etoposide, leucovorin and 5-fluorouracil (ELF) regimen in patients with advanced gastric cancer. 32 patients with advanced gastric cancer were treated with oral etoposide (100 mg), leucovorin (3 x 100 mg), and tegafur (3 x 200 mg) over 14-21 days for a maximum of six cycles. Objective response was seen in only 5 patients (16%), stable disease was documented in 7 (22%), while the remaining patients progressed during therapy. The median time to progression was 2.8 months (range 0.7-12 months) and median overall survival was 6 months (range 1-18+ months). Due to grade 3 nausea/emesis, 8 patients discontinued treatment prematurely, while 12 patients experienced anorexia and progressive weight loss. Haematological toxicity was modest, with 4 patients developing asymptomatic grade 3-4 granulocytopenia. We conclude that this oral combination regimen cannot be recommended for the treatment of advanced gastric cancer.  相似文献   
1000.
Shiga toxin-producing Escherichia coli (STEC) strains of serogroup 0118 are the most prevalent group among STEC strains in diarrheic calves in Germany (L. H. Wieler, Ph.D. thesis, University of Giessen, 1997). To define their virulence properties, 42 0118 (0118:H16 [n = 38] and 0118:H- [n = 4]) strains were characterized. The strains displayed three different Stx combinations (Stx1 [36 of 42], Stx1 and Stx2 [2 of 42], and Stx2 [4 of 42]). A total of 41 strains (97.6%) harbored a large virulence-associated plasmid containing hlyEHEC (hly from enterohemorrhagic E. coli). The strains' adhesive properties varied in relation to the eukaryotic cells tested. Only 28 of 42 strains (66.7%) showed localized adhesion (LA) in the human HEp-2 cell line. In contrast, in bovine fetal calf lung (FCL) cells, the number of LA-positive strains was much higher (37 of 42 [88.1%]). The locus of enterocyte effacement (LEE) was detected in 41 strains (97.6%). However, not all LEE-positive strains reacted positively in the fluorescence actin-staining (FAS) test, which indicated the attaching and effacing (AE) lesion. In HEp-2 cells, only 22 strains (52.4%) were FAS positive, while in FCL cells, the number of FAS-positive strains was significantly higher (38 of 42 [90.5%; P < 0.001]). In conclusion, the vast majority of the 0118 STEC strains from calves (41 of 42 [97.6%]) have a high virulence potential (stx, hlyEHEC, and LEE). This virulence potential and the high prevalence of STEC 0118 strains in calves suggest that these strains could be a major health threat for humans in the future. In addition, the poor association between results of the geno- and phenotypical tests to screen for the AE ability of STEC strains calls the diagnostic value of the FAS test into question.  相似文献   
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