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951.
952.
Lead nitrate administered to noninbred rats with drinking water on the level of IO MAC (0.3 mg/l) during the whole period of gestation lead to the strengthening of hepatotoxic effect of cadmium chloride (7.5 and 15 mg/kg daily by gavage from the 1st to 20th day of gestation), manifest in significant increase of the hepatocytes alteration index, increase of the number of the pyknotic cells of reticuloendothelial system, increase of the degree of dams' liver hepatocytes dystrophy, decrease in the specific volume of megakaryocytes in the liver of their fetuses. 相似文献
953.
954.
Rice varieties with similar amylose content differ in starch digestibility and glycemic response in humans 总被引:7,自引:0,他引:7
L N Panlasigui L U Thompson B O Juliano C M Perez S H Yiu G R Greenberg 《The American journal of clinical nutrition》1991,54(5):871-877
Three high-amylose rice varieties, IR42, IR36, and IR62, with similar chemical composition including amylose content (26.7-27.0%), were cooked under the same conditions and tested for in vitro digestibility as well as blood glucose and insulin responses in healthy human volunteers. The starch-digestion rate and the glycemic and insulin responses were the highest in IR42, followed by IR36 and, then IR62. The differences were not due to unabsorbed carbohydrate but were related to their physicochemical properties, such as gelatinization temperature, minimum cooking time, amylograph consistency, and volume expansion upon cooking. When the three varieties were cooked for their minimum cooking time, they had the same degree of gelatinization and their starch-digestion rates and glycemic responses were similar. We conclude that amylose content alone is not a good predictor of starch-digestion rate or glycemic response. Rice varieties with similar high-amylose contents can differ in physicochemical (gelatinization) properties and this, in turn, can influence starch digestibility and blood glucose response. 相似文献
955.
In vivo determination of body fat by measuring total body carbon 总被引:2,自引:0,他引:2
J J Kehayias S B Heymsfield A F LoMonte J Wang R N Pierson 《The American journal of clinical nutrition》1991,53(6):1339-1344
Total body carbon (TBC) is measured in vivo by neutron inelastic scattering. The fast neutrons needed for the irradiation are produced by a miniature deuterium-tritium (D-T) neutron generator. Body fat and protein are the main contributors to TBC. Bone ash and carbohydrates contribute less than 3%. Fat is calculated from TBC after the subtraction of the carbon contributions from protein, bone, and glycogen. The technique was applied to 14 normal volunteers (8 females, 6 males) aged 24-94 y who underwent neutron inelastic scattering and neutron activation measurements for body carbon, nitrogen, and calcium. The initial results agree with other techniques. Unlike models that evaluate body fat by subtracting lean body mass from body weight, the TBC technique is not sensitive to assumptions on the composition of lean body; therefore, it is appropriate for studies of adults of any age and health condition. 相似文献
956.
Effects of a very-low-calorie diet and physical-training regimens on body composition and resting metabolic rate in obese females 总被引:1,自引:0,他引:1
J E Donnelly N P Pronk D J Jacobsen S J Pronk J M Jakicic 《The American journal of clinical nutrition》1991,54(1):56-61
Sixty-nine obese females received 90 d of a liquid diet providing 2184 kJ/d in clinical trials. Groups were diet only (C), diet plus endurance exercise (EE), diet plus weight training (WT), or diet plus endurance exercise and weight training (EEWT). Changes in body weight, percent fat, fat weight, and fat-free mass were not different between groups. Declines in resting metabolic rate (RMR) were approximately 7% to approximately 12% of baseline values with no differences among groups. A significant increase in work capacity (approximately 16%) was shown for EEWT. Strength index showed declines of approximately 6% for C and EE and gains of approximately 3% and approximately 10% for EEWT and WT, respectively. These clinical trials did not show advantages of any exercise regimen over diet alone for weight loss, body-composition changes, or declines in RMR. Improvements in work capacity were limited and strength improved in groups that participated in strength training. 相似文献
957.
OBJECTIVE.--To review our experience with lung transplantation, emphasizing recipient selection, choice of procedure, functional results, and outcome. DESIGN.--Retrospective review of patients who received lung transplants at Barnes Hospital, St Louis, Mo, between July 1, 1988, and January 31, 1991. SETTING.--Washington University School of Medicine, St Louis, Mo, and Barnes Hospital, a medical school and its affiliated referral hospital, respectively. PATIENTS.--Sixty-nine lung transplant procedures were performed in 66 recipients. Patients with clinically and physiologically severe lung disease were selected according to predetermined guidelines. Underlying diseases in the recipients included chronic obstructive pulmonary disease, alpha 1-antitrypsin deficiency emphysema, cystic fibrosis, pulmonary fibrosis, primary pulmonary hypertension, Eisenmenger's syndrome associated with an atrial septal defect, bronchiectasis, eosinophilic granuloma, and lymphangiomyomatosis. INTERVENTION.--Double-lung, bilateral sequential, and single-lung transplantations were performed. Eight patients underwent en bloc double-lung transplantations or a modification of this procedure with separate bronchial anastomoses. Thereafter, the bilateral sequential approach to replacement of both lungs was performed in 26 patients. Thirty-two patients underwent single-lung transplantations. MAIN OUTCOME MEASURES.--Pulmonary function tests, arterial blood gas levels, pulmonary artery pressure, pulmonary vascular resistance, and actuarial survival. RESULTS.--Actuarial survival at 1 year for the 66 lung transplant recipients was 79%. Actuarial survival at 1 year was 82% for the bilateral lung transplant recipients and was 90% for the single-lung transplant recipients. In patients with either restrictive or obstructive lung disease, pulmonary function tests and arterial blood gas levels improved markedly after lung transplantation. In patients with primary pulmonary hypertension or Eisenmenger's syndrome, the pulmonary artery pressure decreased and the cardiac index increased into the normal range after single-lung transplantation. CONCLUSIONS.--In carefully selected patients with end-stage lung disease, single-lung and bilateral lung transplantations can significantly improve functional capacity, with promising early actuarial survival statistics after 1 year. 相似文献
958.
This study assessed the capabilities of a traditional and an amplified stethoscope used by flight nurses to assess breath sound during air medical transport in an MBB BO-105 helicopter. We developed a normal breath sound model using a prerecorded tape of breath sounds interspersed with segments without breath sounds; the recorder had been placed in the chest wall of a resuscitation training manikin. Flight nurses completed control listening sessions in a quiet environment and experimental sessions during flight using a traditional stethoscope for half of the sessions and an amplified stethoscope for the remaining half. In the quiet environment, flight nurses accurately reported the presence or absence of breath sounds in 110 (92%) of 120 trials. During helicopter flight, none of the flight nurses heard breath sounds during any of the recorded segments with either the traditional stethoscope or the amplified stethoscope. We conclude that flight nurses are unable to hear normal breath sounds using a traditional or amplified stethoscope during flight in a medically configured MBB BO-105 helicopter. Improved stethoscopes, innovative methods of listening, and reduction of aircraft noise are potential solutions to the problems of breath sound assessment during air medical transport. 相似文献
959.
960.
The paper reviews existing reports on relations between pathologies leading to malabsorption and dental lesion in children. The following dental alterations are reported in the literature: delayed eruption of deciduous teeth, hypoplasia of enamel and dental caries. These lesions have been observed in gastrointestinal pathologies, for example, coeliac disease, chronic diarrhea and recurrent vomiting, intolerance of cow's milk protein, Crohn's disease and salmonellosis. The delayed eruption of deciduous teeth and hypoplasia of the enamel are certainly correlated to malabsorption and maldigestion, especially if these are protracted over time. Dental caries may be due to poor oral hygiene, poor diet and to the presence of modified calcification. Only a comparative study with a control group will enable the effective prevalence to be assessed. 相似文献