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11.
Although a great deal is known about the nature and severity of the recent financial crisis in agriculture, there has been little systematic study of the social and psychological effects of this crisis upon farm operators and their families. Using data from a statewide sample of Iowa farmers, this study tests some hypotheses about correlates of psychological stress. The findings suggest that many farm operators find their situations to be stressful and that such stress is related to the severity of their financial problems. In addition, the life-events perspective is examined in its utility to explain how adverse economic changes impact psychological well-being. 相似文献
12.
As the body of medical literature continues to expand, physicians must develop the necessary skills to keep up with the vast amount of information available. The journal club provides a forum to allow residents to remain current with the literature while also teaching them the methods to evaluate it critically. Those readers wishing to start a journal club or revive an existing one should begin by designating a leader and defining the conference goals. Emphasizing the importance of this conference in the educational process while allowing it to be structured to optimise resident interest and attendance will help to ensure its success. Periodic evaluation of this conference will allow the organisers to assess the concordance of the resident''s goals with those of the faculty. Formal evaluation will also provide an objective assessment of the knowledge gained by the house-staff through participation in journal club. 相似文献
13.
Characteristic features of MR truncation artifacts 总被引:1,自引:0,他引:1
L F Czervionke J M Czervionke D L Daniels V M Haughton 《AJR. American journal of roentgenology》1988,151(6):1219-1228
Truncation artifacts occur in MR imaging because Fourier transforms are used to process MR signal data. These artifacts may alter the intensity, shape, and anatomic detail of structures in the spine. Ring artifacts (Gibb phenomenon) occurring near highly contrasting interfaces represent but one manifestation of truncation artifacts visible on MR images. We review truncation phenomena by providing graphic and phantom models. Ways in which truncation artifacts alter the MR appearance of the spine are discussed. We found that truncation phenomena are reduced most effectively by using a 256 x 256 matrix whenever feasible. 相似文献
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R. M. Fairchild C. E. J. Daniels P. R. Ellis† 《Journal of human nutrition and dietetics》1990,3(5):311-316
A food frequency of consumption questionnaire was completed by 137 diabetic outpatients attending the University of Wales Hospital in Cardiff, to provide information about the use of special dietary products.
Seventy-four per cent of the diabetics used special dietary products, the most popular of which were artificial sweeteners (45%) and preserves (47%), followed by squash (34%), sweets (31%) and chocolate (31%). Twenty per cent of diabetics consumed biscuits and tinned fruit. Cake and other products (e.g. jelly), were used by less than 10% of the respondents. Over half of all the diabetics consumed one or more products on a daily basis. The use of special products bore no significant relationship to the sex of the respondents, nor to the duration of the diabetes. However, a significantly higher proportion of the Insulin Dependent Diabetics (IDDM) group used dietary products compared with the Non-Insulin Dependent Diabetics (NIDDM) group. This can be explained largely by the differences in age between the diabetics; the under-18-year-old age group (who were all IDDM respondents) were the greatest users of sweets, chocolate and squash.
Forty-three per cent of diabetics who did not use special food products cited at least one reason for non-use. The reasons included dietetic advice (NIDDM respondents only), high cost, poor palatability, lack of availability and unsuitability for other members of the family. 相似文献
Seventy-four per cent of the diabetics used special dietary products, the most popular of which were artificial sweeteners (45%) and preserves (47%), followed by squash (34%), sweets (31%) and chocolate (31%). Twenty per cent of diabetics consumed biscuits and tinned fruit. Cake and other products (e.g. jelly), were used by less than 10% of the respondents. Over half of all the diabetics consumed one or more products on a daily basis. The use of special products bore no significant relationship to the sex of the respondents, nor to the duration of the diabetes. However, a significantly higher proportion of the Insulin Dependent Diabetics (IDDM) group used dietary products compared with the Non-Insulin Dependent Diabetics (NIDDM) group. This can be explained largely by the differences in age between the diabetics; the under-18-year-old age group (who were all IDDM respondents) were the greatest users of sweets, chocolate and squash.
Forty-three per cent of diabetics who did not use special food products cited at least one reason for non-use. The reasons included dietetic advice (NIDDM respondents only), high cost, poor palatability, lack of availability and unsuitability for other members of the family. 相似文献
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Nathan J Koewler Katie T Freeman Ryan J Buus Monica B Herrera Juan M Jimenez-Andrade Joseph R Ghilardi Christopher M Peters Lucy J Sullivan Michael A Kuskowski Jack L Lewis Patrick W Mantyh 《Journal of bone and mineral research》2007,22(11):1732-1742
A closed femur fracture pain model was developed in the C57BL/6J mouse. One day after fracture, a monoclonal antibody raised against nerve growth factor (anti-NGF) was delivered intraperitoneally and resulted in a reduction in fracture pain-related behaviors of approximately 50%. Anti-NGF therapy did not interfere with bone healing as assessed by mechanical testing and histomorphometric analysis. INTRODUCTION: Current therapies to treat skeletal fracture pain are limited. This is because of the side effect profile of available analgesics and the scarcity of animal models that can be used to understand the mechanisms that drive this pain. Whereas previous studies have shown that mineralized bone, marrow, and periosteum are innervated by sensory and sympathetic fibers, it is not understood how skeletal pain is generated and maintained even in common conditions such as osteoarthritis, low back pain, or fracture. MATERIALS AND METHODS: In this study, we characterized the pain-related behaviors after a closed femur fracture in the C57BL/6J mouse. Additionally, we assessed the effect of a monoclonal antibody that binds to and sequesters nerve growth factor (anti-NGF) on pain-related behaviors and bone healing (mechanical properties and histomorphometric analysis) after fracture. RESULTS: Administration of anti-NGF therapy (10 mg/kg, days 1, 6, and 11 after fracture) resulted in a reduction of fracture pain-related behaviors of approximately 50%. Attenuation of fracture pain was evident as early as 24 h after the initial dosing and remained efficacious throughout the course of fracture pain. Anti-NGF therapy did not modify biomechanical properties of the femur or histomorphometric indices of bone healing. CONCLUSIONS: These findings suggest that therapies that target NGF or its cognate receptor(s) may be effective in attenuating nonmalignant fracture pain without interfering with bone healing. 相似文献
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Five strains of infectious bronchitis virus isolated from commercial chickens from the state of Pennsylvania, USA during the years 1998 and 1999 were studied. The strains were selected for cross-challenge in specific pathogen free chickens and virus neutralization in chick embryos on the basis of partial S1 sequence amino acid identity values. The partial sequences analysed spanned the hypervariable amino terminus region of S1 from amino acid residues 48 to 219, based on the Beaudette strain. Using their S1 identity values, the strains represented a continuum of genetic, and thus antigenic, relationships. When compared with strain PA/5083/99, strain PA/Wolgemuth/98 had high sequence identity (96%) followed by PA/171/99 (85%), PA/5344/98 (70%) and PA/1220/98 (34%). The method of Archetti and Horsfall was used for calculating antigenic relatedness values of virus neutralization tests. The same formula was also applied to the percentage protection values of cross-challenge tests to derive protective relatedness values among the strains. The antigenic relatedness values, protective relatedness values, and the partial S1 sequence identity values were then analysed. The findings indicated partial S1 sequence identity values were more strongly correlated with protective relatedness values and than antigenic relatedness values. 相似文献