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Veterans who were eligible for dental care in Department of Veterans Affairs (VA) facilities at no monetary cost responded to a mailed questionnaire. Seventy-one percent were aware that they were actually eligible for VA dental care. However, only 48 percent reported the VA as their only or primary source of dental care. Eligibility status, perceived quality of VA dental care, use of VA medical care, perception that one's income meets expenses, and perceived need for dental care were significant correlates of using the VA as one's current source of dental care. Level of formal education, perception that one's income meets expenses, transportation pattern, geographic distance from a VA facility, and eligibility status were significant correlates of using the VA as one's current medical care source. Research on VA utilization offers the opportunity to study issues of access to, and use of, a large public health care system whose patients largely receive care at no monetary cost. Veterans' use of VA dental and medical care is apparently influenced by a wide variety of factors, ranging from barriers to access to non-VA systems, to characteristics of the VA delivery system itself, to need for treatment.  相似文献   
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The dietary data from case-control studies of breast, prostate, and lung cancer in Hawaii revealed that saturated fat was a risk factor for these malignancies. The dietary intakes from the three studies were used to calculate the attributable risk (AR) due to saturated fat. For all ethnic groups combined, the ARs for the highest quartiles of intake were 14.9 percent for female breast cancer, 13.0 percent for prostate cancer, and 23.1 percent for male lung cancer. Our results suggested that a reduction of saturated fat to the lowest quartiles of intake could result in a 10 to 20 percent decrease in risk for these three cancers in Hawaii. We also examined the ethnic-specific risks associated with saturated fat consumption among the Japanese and the Caucasians in the three studies. The ARs for the highest quartiles of intake were notably higher among the Caucasians than the Japanese, primarily due to the difference in their dietary patterns. Although the calculated AR due to saturated fat was higher among the Caucasians than among the Japanese, all persons in the population would derive considerable benefit by reducing their intake of this nutrient.Authors are with the Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii, 1236 Lauhala Street, Honolulu, HI 96813, USA. Address correspondence to Dr Hankin. This study was supported in part by NIH Grant PO1 CA 33619.  相似文献   
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Acquired Loss of Red-Cell Wj Antigen in a Patient with Hodgkin''s Disease   总被引:2,自引:0,他引:2  
A patient with Hodgkin's disease became temporarily Wj-negative with alloanti-Wj in his serum. Four human autoantibodies, and 1 of 2 murine monoclonal antibodies, with serological characteristics of anti-Wj were nonreactive with his red cells, confirming that they have anti-Wj specificity. Six siblings of the patient are all Wj-positive. The patient was also temporarily Anton-negative, and cross-testing between Wj and Anton red cells and antisera showed mutual compatibility, indicating that the antigens are the same. The patient and 3 of his 6 siblings are also of the rare Lu: - 13 phenotype, providing the first evidence that this is an inherited characteristic.  相似文献   
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Immunotherapy requiring an efficient T lymphocyte response is initiated by antigen delivery to antigen-presenting cells. Several studies have assessed the efficiency of various antigen loading procedures, including microbial vectors. Here a live strain of Pseudomonas aeruginosa was engineered to translocate a recombinant antigenic protein into mammalian cells via the type III secretion system, a bacterial device translocating effector proteins into host cells. Optimization of the vector included virulence attenuation and determination of the N-terminal sequence allowing translocation of fused antigens into cells. In vitro delivery of an ovalbumin fragment by the bacterial vector into dendritic cells induced the activation of ovalbumin-specific CD8(+) T lymphocytes. Mice injected with the ovalbumin-delivering vector developed ovalbumin-specific CD8(+) T lymphocytes and were resistant to a subsequent challenge with an ovalbumin-expressing melanoma. Moreover, in a curative assay, injection of the vaccine vector 5 and 12 days after tumor implantation led to a complete cure in five of six animals. These results highlight the utility of type III secretion system-based vectors for anti-tumor immunotherapy.  相似文献   
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Summary Five Rhesus Monkeys (Maccaca mulatta), a suitable nonhuman model, performed 5 months of ropeclimbing exercise. Duration of the training sessions was progressively increased to reach 1 hour/day after 1 month of training and was maintained until the end of the experiment. Bone mass parameters, bone resorption, and bone formation activity were measured by histomorphometric analysis on iliac crest bone biopsies before and after the experiment. Mineral apposition rate was measured in cortices and trabecular bone after double calcein labeling. Five months of rope-climbing exercise had determined a significant decrease of bone volume with a slight decrease of the number and thickness of trabeculae. This might induce an alteration of biomechanical properties of bone. These architectural modifications were associated with a nonsignificant decrease of bone resorption activity. But the main effect of training was an important decrease of bone formation activity without change of the mineral apposition rate. Endurance exercise at low intensity has determined a decreased bone turnover with osteoblastic depression. This animal experiment points out that exercise modalities might be important in the bone response to training and should be carefully defined for preventive use in humans.  相似文献   
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