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51.
Lycopene (lyc) has emerged as a primary candidate for dietary interventions of prostate cancer; however, research regarding its absorption, tissue distribution, and metabolism is limited. Previously, we evaluated the biodistribution (3-168 h) of a single oral dose of 14C-lyc in rats prefed lyc for 30 d. The liver was the primary depot for lyc, and the 14C and 14C-polar products appeared in tissues as early as 3 h after dosing. In the current study, F344 rats (n = 48) were randomly assigned to 1 of 4 groups prefed either a control or lyc-enriched diet (0.25 g lyc/kg diet) for 30 d and killed at 5 or 24 h after receiving a single oral dose of 14C-lyc. The percentage of the 14C dose absorbed at 24 h was lower (5.5 +/- 0.5%) in lyc-prefed (LP) rats than in control-prefed (CP) rats (6.9 +/- 0.4%, P < 0.04). Hepatic total 14C and 14C-lyc in CP rats was greater than in LP rats at 24 h (P < 0.005). A portion of 14C was delivered to extrahepatic tissues as early as 5 h, irrespective of diet. Of the tissues analyzed, an increase in the percentage in 14C-polar products occurred between 5 and 24 h only in the prostate and seminal vesicles, suggesting increased accumulation of 14C-polar products in these tissues, irrespective of prior dietary treatment. These data suggest that lyc absorption, tissue uptake, and catabolism were affected by prefeeding and that lyc can be partially taken up by extrahepatic tissues from the postprandial triglyceride-rich fraction.  相似文献   
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Domestic poultry and SARS coronavirus, southern China   总被引:1,自引:0,他引:1  
SARS coronavirus injected intratracheally into chickens, turkeys, geese, ducks, and quail, or into the allantoic sac of their embryonating eggs, failed to cause disease or replicate. This finding suggests that domestic poultry were unlikely to have been the reservoir, or associated with dissemination, of SARS coronavirus in the animal markets of southern China.  相似文献   
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To better assess the risk for transmission of the severe acute respiratory syndrome-associated coronavirus (SARS-CoV), we obtained serial specimens and clinical and exposure data from seven confirmed U.S. SARS patients and their 10 household contacts. SARS-CoV was detected in a day-14 sputum specimen from one case-patient and in five stool specimens from two case-patients. In one case-patient, SARS-CoV persisted in stool for at least 26 days after symptom onset. The highest amounts of virus were in the day-14 sputum sample and a day-14 stool sample. Residual respiratory symptoms were still present in recovered SARS case-patients 2 months after illness onset. Possible transmission of SARS-CoV occurred in one household contact, but this person had also traveled to a SARS-affected area. The data suggest that SARS-CoV is not always transmitted efficiently. Routine collection and testing of stool and sputum specimens of probable SARS case-patients may help the early detection of SARS-CoV infection.  相似文献   
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Interest in the health benefits of soy foods has been intense among the research community, health professionals, and the public. At the same time, potential concerns associated with soy consumption, especially as related to soy isoflavones, have tempered the enthusiasm for making public health recommendations. On both accounts, the primary soybean isoflavone, genistein, has received the most attention. Because consumers are becoming increasingly confused by the often conflicting dietary messages, a balanced and accurate view of the risks and benefits of soy foods and soy food components is essential. Even among health professionals, confusion exists about proper nomenclature and about the precise composition of the agents under investigation. Levels of isoflavones are frequently assumed to be constant within categories of soy foods, and intakes are estimated rather than being directly analyzed. Furthermore, all too often research dealing singularly with genistein is interpreted by both health professionals and the media as equating directly with soy. Researchers often fail to fully understand the implications of their research outcomes and the context in which those outcomes should be placed. With the hundreds of publications yearly on soy and isoflavones, it is especially important to consider the literature in its entirety when making pronouncements about health effects. Efforts are needed by all to reduce the public confusion by adapting standardized approaches to the reporting of data. This paper provides a framework for both standardization of nomenclature and appropriate interpretation of data.  相似文献   
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Axial unloading therapy device for cervical spine rehabilitation   总被引:2,自引:0,他引:2  
There is an ongoing need for therapeutic cervical traction to treat chronic idiopathic neck pain. A device was designed to perform low-load cervical traction (unloading) with the patient in an upright, seated, neutral spine position. A prototype device meeting these requirements was constructed. During subsequent use, several methods for assessing the outcome of such unloading were proposed, including radiographic images, cervical range-of-motion measurements and muscle EMG activity. The prototype and measurement methods were tested on a population of normal subjects. The results demonstrated that the device design is safe and effectively transfers load into the occipital region of the skull. The use of low-load cervical unloading induced lateral rotation and posterior lengthening of the spine. Device refinements were identified. The results demonstrated that the methods described may be safely employed on a patient population.  相似文献   
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BACKGROUND: Various definitions of both group cohesion and working alliance are used in theories on group psychotherapy, making the study of their relative contribution to the treatment outcome difficult. In this study, two different, nonoverlapping questionnaires were used to explore the relationship between group cohesion, working alliance and treatment outcome in a time-limited, structured cognitive behavioral group psychotherapy aiming at the reduction of coronary risk factors. METHODS: After having undergone percutaneous transluminal coronary angioplasty, 42 patients were treated with the aim to reduce exhaustion, anxiety, hostility and depression. The newly developed Group Cohesion Questionnaire (GCQ) and the Helping Alliance Questionnaire (HAQ-II, measuring the bond between individual patients and the group psychotherapist) were administered after the fifth and tenth treatment session. Exhaustion, quality of life, anxiety, blood pressure and heart rate were measured before and after treatment. To test the relationship between the GCQ, the HAQ-II and outcome variables, Pearson Product-Moment correlations and hierarchical regression was applied. RESULTS: Principal Component Analysis of the GCQ yielded two dimensions, the bond with the group as a whole and the bond with other group members. Hierarchical regression showed that both the bond with other group members and working alliance contributed significantly and independently to the prediction of posttreatment systolic and diastolic blood pressure as well as posttreatment quality of life (confidence). CONCLUSIONS: Conceptually and empirically, group cohesion and the working alliance may be considered to represent different relationships in a psychotherapy group, contributing in different ways to the treatment outcome in cardiac patients receiving cognitive behavioral group psychotherapy.  相似文献   
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