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991.

Background

We aimed to find some new indicators for tonsillectomy (TE) in adults with recurrent tonsillitis (RT) by exploring whether the frequency of tonsillitis episodes and the length of morbidity period are associated with the macroscopic signs of sclerotic process in tonsils and microbiological data assessed by culture, molecular (PCR) and transmission electron microscopy (EM) methods.

Methods

The study involved 62 RT patients admitted for TE (age range 15–35, median 22 years) and 54 healthy volunteers (age range 18–24, median 20 years). The index of tonsillitis (IT) was calculated by multiplying the number of tonsillitis episodes per year by the morbidity period in years. On oropharyngeal examination the presence or absence of three sclerotic signs was evaluated: tonsillar sclerosis, obstruction of tonsillar crypts and scar tissue on the tonsils. The occurrence of Streptococcus pyogenes was assessed by culture and PCR methods in 24 tonsillar core specimens. The samples for EM investigation of crypt epithelium were taken from 10 removed tonsils.

Results

The IT values were in positive correlation with the number of sclerotic signs on oropharyngeal examination (r = 0.325, P = 0.010). Based on the IT values and the presence or absence of tonsillar sclerosis and obstruction of tonsillar crypts the receiver-operating curve (ROC) was constructed. It revealed that an IT score of 36 is an optimal cut-off value for prediction of sclerotic type tonsils. S. pyogenes was never found by culture, but its presence by PCR in nearly one third (29%) of diseased tonsillar tissue specimens was tightly associated with longer morbidity. EM revealed coccoid forms of intracellular bacteria in the crypt epithelium, which was accompanied with the damage of tight junctions between epithelial cells.

Conclusion

The index of tonsillitis ≥36, being a combination between the frequency of tonsillitis and the length of morbidity period, predicts the sclerotic process in recurrently inflamed tonsils. Therefore, the high IT values could serve as an indicator for TE in adults. The correlation between the longer morbidity period and the presence of S. pyogenes by PCR suggests that persistent infection may have a role in maintenance of recurrent inflammation in tonsils.  相似文献   
992.
993.
Brain edema: ultrasound examination   总被引:4,自引:0,他引:4  
Sonographic examination of the brain in 10 patients who had cortical mass lesions was performed. Results were compared with findings of CT. In each case, brain edema surrounded the lesion, and the adjacent white matter had a diffusely echo-genic appearance that corresponded to the area of brain edema seen on CT.  相似文献   
994.
Management of intramedullary spinal cord tumors   总被引:10,自引:0,他引:10  
  相似文献   
995.
White  RM; Levine  MS; Enterline  HT; Laufer  I 《Radiology》1985,155(1):25-27
Early gastric cancer (EGC) is defined as carcinoma in which malignant invasion is limited to the mucosa or submucosa. Records of pathologic examinations from the Hospital of the University of Pennsylvania show that EGC comprised 6% of all gastric carcinomas diagnosed between 1977 and 1983 (7/118 cases) compared with 8.2% of gastric carcinomas diagnosed between 1965 and 1977 (12/147 cases). Double contrast radiographic techniques and fiberoptic endoscopy became widely available at our institution in 1976. Thus, the application of these techniques to symptomatic patients has not improved our ability to diagnose EGC. In contrast, the incidence of EGC in Japan has risen from 5% to 35% with the widespread use of these diagnostic techniques. This discrepancy can be attributed to mass screening of asymptomatic patients in Japan because of the unusually high prevalence of gastric carcinoma in that country. American radiologists and endoscopists should therefore recognize that they are unlikely to experience a significant increase in the detection of EGC as long as these examinations are performed predominantly on symptomatic patients.  相似文献   
996.
Respiratory-related changes in length of the nasal dilator muscle, the alae nasi muscle, were measured using sonomicrometry in ten anesthetized (pentobarbital), tracheostomized, spontaneously breathing dogs. Piezoelectric crystals were inserted 7-25 mm apart along the direction of the alae nasi muscle fibers, and the effects of progressive hyperoxic hypercapnia and a peripheral and central chemoreceptor stimulant, nicotine (10-500 micrograms intravenously), were ascertained. The alae nasi shortened during inspiration in all animals, started to lengthen again towards the end of inspiration, returned to resting length during the first portion of expiration (Te-1), and remained at resting length for the remainder of expiration (Te-2). The amount of alae nasi inspiratory shortening was increased by occluding the airway for a single breath. Progressive hypercapnia caused progressive increases in the amount and velocity of nasal muscle inspiratory shortening during both unoccluded and occluded breaths; similar stimulatory effects on inspiratory shortening were seen following nicotine administration. Furthermore, both chemoreceptor stimulants caused a delay in the return of the muscle to its resting length during expiration, resulting in a significant increase in Te-1 relative to Te (Te-1/Te), and a greater amount of nasal muscle shortening to be present during Te-1. In some animals these agents also caused tonic shortening of the alae nasi, so that the muscle never returned to its resting length. These results suggest that inspiratory shortening of the alae nasi is inhibited by vagal inputs, but that chemoreceptor activation increases the amount of muscle shortening during both inspiration and early expiration.  相似文献   
997.
Long-term betaxolol therapy in glaucoma patients with pulmonary disease   总被引:2,自引:0,他引:2  
We evaluated the use of topically administered betaxolol 0.5% in 101 glaucoma patients (47 men and 54 women) who had chronic obstructive pulmonary disease, asthma, or timolol-induced bronchoconstriction. Betaxolol 0.5% was administered twice daily and patients were reexamined at three-month intervals for up to two years. In addition to measurement of intraocular pressure, pulmonary function tests were obtained before therapy (baseline), two or three weeks after initiating betaxolol therapy, and at yearly intervals. Before treatment with betaxolol, the mean ratio of forced expiratory volumes in one second (FEV1) to forced vital capacity (FVC) was 66.3% (n = 101). After two weeks of betaxolol treatment, mean FEV1/FVC ratio was 66.2% (n = 101). After one year of betaxolol therapy, mean FEV1/FVC ratio was 60.1% (n = 24), and after two years it was 54.4% (n = 5). Nine patients developed symptoms that may have been associated with betaxolol treatment and were withdrawn from the study. Five of these patients developed symptomatic pulmonary obstruction between one and 554 days after initiating betaxolol treatment. Topically administered betaxolol was well tolerated by most glaucoma patients with concomitant pulmonary disease.  相似文献   
998.

Background

Spina Bifida (SB) is the second most common birth defect worldwide. Since the chances of survival in children with severe SB-forms have increased, medical care has shifted its emphasis from life-saving interventions to fostering the quality of life for these children and their families. Little is known, however, about the impact of SB on family adjustment. Reviewers have struggled to synthesize the few contradictory studies available. In this systematic review a new attempt was made to summarize the findings by using meta-analysis and by delimiting the scope of review to one concept of family adjustment: Parents' psychological adjustment. The questions addressed were: (a) do parents of children with SB have more psychological distress than controls? (b) do mothers and fathers differ? and (c) which factors correlate with variations in psychological adjustment?

Methods

PsycInfo, Medline, and reference lists were scanned. Thirty-three relevant studies were identified of which 15 were eligible for meta-analysis.

Results

SB had a negative medium-large effect on parents' psychological adjustment. The effect was more heterogeneous for mothers than for fathers. In the reviewed studies child factors (age, conduct problems, emotional problems, and mental retardation), parent factors (SES, hope, appraised stress, coping, and parenting competence), family factors (family income, partner relationship, and family climate), and environmental factors (social support) were found to be associated with variations in parents' psychological adjustment.

Conclusion

Meta-analysis proved to be helpful in organizing studies. Clinical implications indicate a need to be especially alert to psychological suffering in mothers of children with SB. Future research should increase sample sizes through multi-center collaborations.
  相似文献   
999.
1000.
Dichlorphenamide was administered to 13 patients with chronic respiratory failure, and the effects on gas exchange at rest and during exercise and on the acid-base state of CSF were observed. The ventilation for a given level of CO2 production was increased both at rest and during exercise, resulting in an increased arterial Po2 and decreased Pco2.

The ventilatory stimulation paralleled the development of a metabolic acidosis but was not associated with tissue CO2 accumulation. Indeed, CSF Pco2 and the oxygenated mixed venous (rebreathing) Pco2 fell by the same amount as arterial Pco2. The level of CO2 elimination after two minutes of exercise was as great for a given work load after dichlorphenamide as before. These findings do not support the view that the drug impairs CO2 transport from tissues either at rest or during exercise. They are most consistent with the view that the primary locus of action of dichlorphenamide in therapeutic doses is the kidney. The metabolic acidosis which results is likely the basis of the respiratory stimulatin, perhaps by its effects on the CSF H2CO3-HCO3 - system. Inhibition of carbonic anhydrase in the red cell and choroid plexus are probably unimportant effects.

  相似文献   
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