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In this study of the modification of anxiety-related disruptive behavior in dental treatment, matched groups of inner-city children attending a pedodontic clinic were shown a videotaped demonstration of a 4-year-old black child undergoing a dental restorative procedure or were given an unrelated drawing task before dental treatment. Children who viewed the videotape demonstration of a peer model coping with dental procedures showed significantly fewer fear-related disruptive behaviors during restoration of lesions. Observations of children's anxiety levels made by dentists and independent observers validated the effectiveness of viewing the videotaped demonstration. No significant correlation was found between the children's reports of their anxiety and their behavior during dental treatment.  相似文献   
74.
The acceleration of tumor production in mice by repeated application of polycyclic aromatic hydrocarbon carcinogens of high and low potency in the presence of cocarcinogenic compounds is described. Experiments exploring the concentration levels of carcinogen and cocarcinogen necessary to produce tumors demonstrate that there is a 1,000-fold increase in the enhancement of potency of low concentrations of benzo[a]pyrene and benz[a]anthracene when n-dodecane is the diluent. The effect of cocarcinogens is most obvious during exposure to low concentrations of carcinogen. The implications of this observation in the environment is discussed.  相似文献   
75.
Book Received     
There exist numerous difficulties in the recruitment of patients to drug trials for Alzheimer's disease. This article describes a successful community-based case-finding strategy. The success is largely attributed to effective liaison between the co-ordinating psychiatrist, GPs, community psychiatric nurses and practice nurses.  相似文献   
76.
To determine the optimal width of a midline posterior spinal block (MPSB) (to avoid delivering too great a dose to the cord and too small a dose to adjacent tissue), the authors determined with magnetic resonance (MR) imaging normal ranges of cord depth and width and correlated them with film dosimetric data. In 59 randomly selected patients there was a wide range for both depth and width. The average depths of the anterior and posterior surfaces of the cord were 6.7 cm +/- 1.4 and 5.4 cm +/- 1.3, respectively. The average cord width was 1.6 cm +/- 0.4. Optimal cord block width as a function of cord width was determined for a 6-MV photon beam. The optimal cord block width at the surface (half-value layer [HVL] thickness = 6) varied from 1.5 to 3.0 cm for cord widths of 0.8-2.4 cm, which correspond to two standard deviations from the average. There was no significant dependence on depth of the cord. For optimal treatment outcome, the MPSB width may have to be determined for each patient individually.  相似文献   
77.
Constitutional pure red cell aplasia (CPRCA) is a syndrome of failed erythropoiesis usually diagnosed within the first year of life. Four patients with CPRCA received transplants with marrow from their HLA- identical, mixed lymphocyte culture-nonreactive siblings. All patients were resistant to corticosteroid therapy and were dependent on regular red cell transfusions for at least 5 years. Three patients were conditioned with procarbazine, antithymocyte globulin, cyclophosphamide, and busulfan, and one was conditioned with antithymocyte serum, cyclophosphamide, and busulfan. Three patients promptly had successful engraftments with establishment of donor hematopoiesis. One patient initially rejected his graft but received a successful retransplant. All patients are currently alive with Karnofsky performance scores of 100 and normal erythropoiesis of donor origin. Despite a history of multiple transfusions, bone marrow transplantation is a potentially curative therapy for patients with CPRCA.  相似文献   
78.
To study carriage of multiply resistant gram-negative bacilli, 50 patients admitted to the hospital from nursing homes (NHs) and 50 control admissions not from NHs were matched for age and recent antibiotic use. Their antibiotic resistance patterns were similar: 20 NH patients and 14 controls had resistant strains. However, significantly more patients (64%) from NHs with large numbers of "skilled beds" had resistant bacteria than did patients from small NHs (21%) or controls (28%). Also, more patients from NHs had members of the Proteus-Providencia-Morganella group in their urine than did controls. Discriminant analysis showed that residence in NHs with large numbers of skilled beds, recent antibiotic use, and bladder dysfunction (indwelling catheter or incontinence) were independently important in predicting carriage of resistant strains in NH and control patients. Over 75% of resistant isolates were from rectal specimens, emphasizing the occult way that such strains are brought into the hospital.  相似文献   
79.
The effects of chronic exercise training and diet modification on serum lipids and lipoproteins were measured in 17 hypertensive males and 41 normotensive males with documented coronary artery disease (CAD). Exercise consisted of aerobic activities which were performed at approximately 75-85% of the symptom-limited maximum heart rate for 30-40 minutes, three times weekly for 3 months. Each participant's diet was also controlled, the recommended daily intake of fat and cholesterol was no more than 40 g/day and 200 mg/day, respectively. Significant increases in estimated VO2max and total cholesterol/high density lipoprotein (HDL) and a significant decrease in serum triglycerides were documented after training. Significant differences in serum cholesterol and triglycerides between the nondiuretic and diuretic patients were also noted. No significant changes were found in low density lipoprotein (LDL), HDL, or body weight. Vigorous aerobic training and diet modification can favorably modify the deleterious effects of diuretic medications on serum triglycerides and total cholesterol/HDL in patients with documented CAD.  相似文献   
80.
The activity of the angiotensin I converting enzyme was measured in 55 patients with untreated essential hypertension, 11 patients with untreated renovascular hypertension, five patients with untreated primary aldosteronism, and 23 normotensive subjects. Converting enzyme activity was significantly higher (p less than 0.025 or less) in essential hypertension (28 +/- 1 units/ml) and renovascular hypertension (28.5 +/- 3 units/ml) when compared with the activity in the normotensive subjects (21 +/- 1.5 units/ml). Seventeen (31 percent) of the patients with essential hypertension and three (27 percent) patients with renovascular hypertension had an elevated converting enzyme activity above the mean +2 standard deviations value of the normotensive subjects (32.8 units/ml), ranging from 33 to 55.8 units/ml. Converting enzyme activity was similar in black and white patients and in male and female patients, but it tended to decrease with increasing age in both the hypertensive and the normotensive subjects. In the untreated patients with essential hypertension (n = 55), converting enzyme activity was inversely related to mean arterial pressure and age (r = -0.34, p less than 0.01) and positively related to plasma renin activity (r = 0.31, p less than 0.05). Converting enzyme activity was always decreased during captopril therapy, and it was not affected by beta blockers, but it was increased by diuretics. These findings indicate that converting enzyme activity is elevated in patients with essential and renovascular hypertension.  相似文献   
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