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961.
OBJECTIVE: To compare the behavior of macrosomic newborns who were vaginally delivered of healthy mothers without diabetes with that of non-macrosomic, appropriate-for-gestational-age (AGA) newborns. DESIGN/SETTING: Newborns were recruited conveniently from a tertiary hospital. Newborns were examined at 12-24 and 36-48 hours of age, using the Brazelton Neonatal Behavioral Assessment Scale (NBAS). PARTICIPANTS: Thirty macrosomic newborns who were delivered vaginally were matched with AGA newborns for ethnicity, maternal education, parity, and obstetric medications. MAIN OUTCOME MEASURES: Dimensions scores derived from the individual NBAS items measured reflex functioning, response decrement, orientation, motor processes, range of state, autonomic stability, and regulation of state. RESULTS: Macrosomic newborns performed weaker than AGA newborns on the reflex and motor dimensions. Both groups displayed improved motor scores on Day 2, but regulation of state scores were weaker. For orientation, AGA newborns scored higher on Day 1, and macrosomic newborns scored higher on Day 2. CONCLUSIONS: Increased head, limb, and body mass of macrosomic newborns, compared with adjacent and overall muscle strength, might have interfered with the execution of coordinated movements. Nurses can inform mothers of changes they can expect in their newborns' behavior. 相似文献
962.
N Sonveaux AB Shapiro E Goormaghtigh V Ling JM Ruysschaert 《Canadian Metallurgical Quarterly》1996,271(40):24617-24624
The structure of purified P-glycoprotein functionally reconstituted into liposomes was investigated by attenuated total reflection Fourier transform infrared spectroscopy. A quantitative evaluation of the secondary structure and a kinetic of 2H/H exchange of the P-glycoprotein were performed both in the presence and in the absence of MgATP, MgATP-verapamil, and MgADP. This approach was previously shown to be a useful tool to detect tertiary structure changes resulting from the interaction between a protein and its specific ligands, as established for the Neurospora crassa H+-ATPase. 2H/H exchange measurements provided evidence that a large fraction of the P-glycoprotein is poorly accessible to the aqueous medium. Addition of MgATP induced an increased accessibility to the solvent of a population of amino acids, while addition of MgATP-verapamil resulted in a subtraction of a part of the protein from access to the aqueous solvent. No significant changes were observed upon addition of MgADP or verapamil alone. The secondary structure of P-glycoprotein was not affected by addition of ligands. The variations observed in the 2H/H exchange rate when P-glycoprotein interacted with the above ligands therefore represented tertiary structure changes. Fluorescence quenching experiments confirmed that MgATP-induced changes are to be found in the tertiary structure of the enzyme. 相似文献
963.
964.
Anorexia nervosa and bulimia nervosa are expressed differently in children and adolescents than in adults. Consequently, diagnostic procedures and multidisciplinary treatments need to be tailored to the unique developmental, medical, nutritional, and psychological needs of children and adolescents with eating disorders. This paper reviews current research outlining the differences between child, adolescent, and adult eating disorders. Research is then reviewed concerning the effectiveness of hospitalization, partial hospitalization, individual dynamic therapy, cognitive-behavioral therapy, interpersonal therapy, family therapy, and medication for treating anorexia nervosa, bulimia nervosa, and related eating disorders in children and adolescents. Specific recommendations are made for practitioners to tailor these treatments to their eating-disordered child and adolescent patients, following a stepped-care, decision-tree model of intervention that takes into account the effectiveness, cost, and intrusiveness of the interventions. 相似文献
965.
H Vermund M Boysen JF Evensen AB Jacobsen K Natvig J Tausjo AL Wiley F Winther 《Canadian Metallurgical Quarterly》1998,37(2):167-173
BACKGROUND: Hypoxic tumors are frequently resistant to radiation therapy. Polyethylene glycol conjugated bovine hemoglobin (PEG-Hb) was tested for its ability to increase oxygen tension in the hypoxic rat osteogenic sarcoma UMR-106, murine Lewis lung carcinoma LL2 and rat gliosarcoma 9L. In addition, PEG-Hb was tested as an adjunct for radiotherapy in UMR-106 and human prostate carcinoma PC-3 solid tumors. MATERIAL AND METHODS: Rodents bearing established subcutaneous tumors were intravenously administered PEG-Hb. Tumor surface tissue oxygen tension was measured by both OxySpot and OxyMap systems, which utilize the same phosphorescence quenching method. RESULTS: A time-dependent rise in oxygen tension was noted, and the maximum tissue oxygen tensions were observed two hours post PEG-Hb administration, and sustained for at least 2 hours. Following a single dose radiation of 4 Gray, osteogenic sarcoma tumors in the PEG-Hb treated group showed dramatic regression (complete remission occurred in 100% of the high dose PEG-Hb treated rats), as compared to control (Ringer's lactate) group tumors that showed continued aggressive growth. All PEG-Hb plus radiation treated animals bearing human prostate carcinoma (PC-3) showed significant tumor growth delay compared to both control (Ringer's lactate) and irradiation only treated animals. CONCLUSION: PEG-Hb increased tumor oxygen content and improved the effectiveness of radiotherapy in these rodent models. 相似文献
966.
OBJECTIVES: To assess the risk of total and cardiovascular mortality in older adults with systolic hypertension and with a low ankle-arm index (AAI) as a marker of subclinical peripheral arterial disease (PAD). DESIGN: Prospective observational study PARTICIPANTS: A subgroup of 1537 participants in the Systolic Hypertension in the Elderly Program (SHEP) were screened for lower extremity arterial disease using the AAI. Participants were evaluated at 4 years to determine vital status and cause of death. Total and cardiovascular disease (CVD) mortality rates were assessed in relationship to clinical CVD at baseline, cardiovascular risk factors and the presence of a low AAI (subclinical PAD). RESULTS: Total mortality rates increased as the AAI decreased in those with and without clinical CVD at baseline. In those without clinical CVD at baseline, the presence of an AAI < or = .9 was associated with an age-adjusted relative risk (RR) of 3.00 for total mortality in men and 2.67 in women. Results were similar for CVD mortality and persisted after adjustment for cardiovascular risk factors including the presence of an abnormal electrocardiogram. CONCLUSIONS: A low ankle arm-index predicted a two to three-fold increase in total and cardiovascular mortality in older adults with systolic hypertension of risk for incident cardiovascular disease. In this study of older adults with systolic hypertension, 19.7% of the participants had subclinical PAD. Risk factor modification could be targeted to older adults based on markers of asymptomatic atherosclerosis. 相似文献
967.
Comments on M. C. Pistole's (see record 1995-33117-001) article on adult attachment (AAT) style. Silverman questions Pistole's linkage of insecure AATs and narcissistic pathology and suggests that the lack of uniformity and consistency across AAT studies limits generalizations. Silverman also argues that Pistole conflates divergent theoretical views, thereby further obscuring the meanings of narcissism. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
968.
Energy-filtering transmission electron microscopy has been applied to the quantification of area fractions of calcium-containing cytochemical reaction products in central nervous tissue and the retina of fish. The method of electron spectroscopic imaging using electrons with an energy loss of 250 eV produces images with a very high, structure-sensitive contrast. This is a suitable imaging condition for the reliable detection of reaction products and structural details in unstained ultrathin sections. The images were recorded with a sensitive TV camera and evaluated with the integrated digital image-analysis system of the Zeiss CEM 902 energy-filtering electron microscope. An empirical procedure was developed which objectively detects reaction products and calculates characteristic values, taking into account different staining intensities. This new and sensitive method enabled an assessment to be made of the influence of temperature and light adaptation on cytochemically detectable calcium in nervous tissue of fish. Higher amounts of calcium-containing reaction product were detected in synaptic clefts of the optic tectum in warm-adapted fish than in cold-adapted fish. In synaptic vesicles of photoreceptor cells in the fish retina, higher amounts of reaction product were found in dark-adapted fish than in light-adapted fish. 相似文献
969.
CB Hughes LW Gaber AB Mohey el-Din HP Grewal M Kotb L Mann AO Gaber 《Canadian Metallurgical Quarterly》1996,62(1):8-13
The best method for the diagnosis of osteoporosis and assessment of fracture risk is currently considered to be bone densitometry. The most commonly used dual-energy X-ray absorptiometry (DXA) methods may sometimes not predict bone mass accurately in every skeletal site, are expensive and not widely available. The recent development of computed analysis of a plain radiograph of the hand might provide a practical, inexpensive and rapid method for evaluation of bone mineral status. In this study we evaluated 20 healthy premenopausal and 660 postmenopausal women. In 36 of these subjects a second evaluation was carried out after 2 years of therapy with calcium supplements. The internal and external diameters of the second metacarpal and the metacarpal and ultradistal radial bone density were evaluated using a technical device developed in our laboratory and marketed by NIM, Verona, Italy (Osteoradiometer). The radiographic images, captured by a video camera, were digitized and studied by computed analysis. In 150 subjects bone density at the level of the lumbar spine, femur, and ultradistal and proximal radius was also measured by DXA techniques. Both external (D) and internal (d) diameters increase significantly with age and years since menopause (YSM), whereas metacarpal index (D--d/D) and metacarpal and ultradistal radial bone density decrease significantly with age and YSM. The ratio between metacarpal bone mineral content and the cortical area (volumetric metacarpal bone density) did not change with age. Significant correlations were found between radiometric findings and DXA measurements. The best correlation coefficients were between bone density measured at the level of the ultradistal radius by DXA and radiographic absorptiometry. In the 2-year follow-up study, a 4.9% and 6.2% decline in radial metacarpal bone density respectively were observed, but the difference was statistically significant only for the latter. In conclusion, computed radiogrammetry is closely correlated with all DXA measurements and may be useful in screening of large populations, providing a simple, inexpensive and sufficiently precise method for evaluation of bone mineral status. Further studies are warranted for assessing the accuracy of radiogrammetry for longitudinal investigations and its capacity to predict fracture risk. 相似文献
970.