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排序方式: 共有8142条查询结果,搜索用时 15 毫秒
41.
42.
Wilkinson Karen F. Rush Bob D. Sharma Satish K. Evans David B. Ruwart Mary J. Friis Janice M. Bohanon Michael J. Tomich Paul K. 《Pharmaceutical research》1993,10(4):562-566
We showed previously that a commercially available synthetic tetradecapeptide, Asp-Arg-Val-Tyr-Ile-His-Pro-Phe-His-Leu-Leu-Val-Tyr-Ser, produces authentic angiotensin I (Ang I) upon incubation with the HIV-1 protease (S. K. Sharma et al., Anal. Biochem. 198:363, 1991). Therefore, we developed an Ang-I based activity assay for HIV protease inhibitors based on the technology developed earlier (M. J. Ruwart et al., Pharm. Res. 7:407, 1990; S. K. Sharma et al., Anal. Biochem. 186:24, 1990) for tracking renin inhibitors in rat sera. Ditekiren was either extracted from sera with ethyl acetate or assayed after the interfering substances in sera were precipitated with acetonitrile. Purified recombinant HIV-1 protease was added to extracted rat serum and the enzymatic reaction was initiated in the presence of the tetradecapeptide substrate. The inhibition of Ang I production was measured by a commercially available RIA kit. The cleanup methodology also enabled a commercially available Proteinase Scintillation Proximity Assay (SPA, Amersham) to quantify ditekiren in rat serum through the addition of recombinant HIV-1 protease and cleavage of substrate from SPA beads. Results were confirmed by HPLC or by the renin assay for ditekiren, which inhibits both aspartyl proteases. These technologies should prove useful for assessing serum levels of HIV protease inhibitors in rat. 相似文献
43.
Husaini BA Sherkat DE Levine R Bragg R Van CA Emerson JS Mentes CM 《Journal of the National Medical Association》2002,94(2):100-106
This study examines the effectiveness of breast cancer screening education programs on mammography rates among African-American women 40 years of age and over. We conducted two types of educational programs in community settings, primarily in African-American churches. Three-month follow-up interviews were used to determine whether women who participated in programming were more likely to get a mammogram if they had not had a mammogram in the last year. Our results demonstrate that the educational programs significantly increased the likelihood of getting a mammogram when compared to a control group that received no educational programming. Further, we found that the programs were effective for motivating breast cancer screening in housing projects as well as in the churches, and that the effectiveness of the programs remained even when we controlled for socioeconomic status, depression, and age. 相似文献
44.
Assessment of the epidemic potential of a new strain of rotavirus associated with the novel G9 serotype which caused an outbreak in the United States for the first time in the 1995-1996 season
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Clark HF Lawley DA Schaffer A Patacsil JM Marcello AE Glass RI Jain V Gentsch J 《Journal of clinical microbiology》2004,42(4):1434-1438
Rotavirus causes severe morbidity in developed countries and frequent deaths (> or = 500,000 per year) in less-developed countries. Historically, four serotypes--G1, G2, G3, and G4-have predominated; they are distinguished by one of two surface neutralization antigens (VP7). However, in 1983 and 1984 we described a new rotavirus serotype, designated G9, in five children hospitalized for diarrhea in Philadelphia, Pa. G9 rotavirus was not identified again in the Western Hemisphere until it caused ca. 50% of the rotavirus disease detected in Philadelphia in the 1995-1996 season. This outbreak allowed us to question whether a rotavirus strain completely new to a well-studied community would target either very young infants or older children, cause especially severe disease, or completely displace previously extant serotypes. We observed a significant excess of G9 infections in younger infants (especially in those < 6 months old) that might be attributed to the lack of G9-specific antibodies in mothers. Of further note, six of the seven oldest patients with rotavirus diarrhea were infected with the G9 strains (not significant). However, the age distribution of children with rotavirus did not differ over a 5-year study period regardless of the infecting serotype. Patients with diarrhea associated with G9 strains did not have disease more severe than that caused by the G1, G2, or G3 serotype. G9 strains did not displace the other serotypes but were virtually completely replaced by G1 or G2 serotypes in the three subsequent rotavirus seasons. We conclude that the abrupt appearance of this novel rotavirus serotype did not present a special threat to public health in the community. 相似文献
45.
Integrating complementary and alternative medicine instruction into health professions education: organizational and instructional strategies. 总被引:1,自引:0,他引:1
Mary Y Lee Rita Benn Leslie Wimsatt Jane Cornman Joan Hedgecock Susan Gerik Janice Zeller Mary Jo Kreitzer Pamela Allweiss Claudia Finklestein Aviad Haramati 《Academic medicine》2007,82(10):939-945
A few years ago, the National Institutes of Health National Center for Complementary and Alternative Medicine funded a program called the Complementary and Alternative Medicine (CAM) Education Project. Grantees were 14 medical and nursing schools and the American Medical Student Association, which funded six additional medical schools. Grants were awarded in cohorts of five per year in 2000, 2001, and 2002-2003.The R25 grant recipients identified several major themes as crucial to the success of integrating CAM into health professions curricula. The rationale for integrating CAM curricula was in part to enable future health professionals to provide informed advice as patients dramatically increase the use of CAM. Success of new CAM education programs relied on leadership, including top-down support from institutions' highest administrators. Formal and informal engagement of key faculty and opinion leaders raised awareness, interest, and participation in programs. A range of faculty development efforts increased CAM-teaching capacity. The most effective strategies for integration addressed a key curriculum need and used some form of evidence-based practice framework. Most programs used a combination of instructional delivery strategies, including experiential components and online resources, to address the needs of learners while promoting a high level of ongoing interest in CAM topics. Institutions noted several benefits, including increased faculty development activities, the creation of new programs, and increased cross- and inter-university collaborations. Common challenges included the need for qualified faculty, crowded and changing curricula, a lack of defined best practices in CAM, and post-grant sustainability of programs. 相似文献
46.
Estrogen decreases expression of chemokine receptors, and suppresses chemokine bioactivity in murine monocytes 总被引:5,自引:0,他引:5
Janis K Hoeltke J Nazareth M Fanti P Poppenberg K Aronica SM 《American journal of reproductive immunology (New York, N.Y. : 1989)》2004,51(1):22-31
Problem: We propose that the ability of estrogen exposure to increase the probability of a woman developing breast cancer may be related to decreased chemokine activity and suppression of immune surveillance in mammary tissue. The present study was conducted to determine whether estrogen could decrease monocyte bioactivity through alteration of chemokine receptor expression.
Method of study: We examined the effect of estrogen and tamoxifen on the expression of the chemokine receptors CCR2 and CXCR3 on murine monocytes treated in culture and in vivo . Effects of estrogen on chemokine activation of monocytes were also evaluated.
Results: Estrogen and tamoxifen significantly decreased expression of CCR2 and, to a lesser extent, CXCR3 on murine monocytes. Estrogen decreased chemotaxis of monocytes towards MCP-1/JE. The chemokines MCP-1/JE and MIP-1 α were unable to evoke increases in intracellular calcium in murine monocytes treated with estrogen, alone or in combination with tamoxifen.
Conclusions: Our results show that estrogen suppresses the ability of monocytes to respond to certain chemokines, suggesting that estrogen exposure might decrease immune surveillance in tissues where the action of specific chemokines is involved. 相似文献
Method of study: We examined the effect of estrogen and tamoxifen on the expression of the chemokine receptors CCR2 and CXCR3 on murine monocytes treated in culture and in vivo . Effects of estrogen on chemokine activation of monocytes were also evaluated.
Results: Estrogen and tamoxifen significantly decreased expression of CCR2 and, to a lesser extent, CXCR3 on murine monocytes. Estrogen decreased chemotaxis of monocytes towards MCP-1/JE. The chemokines MCP-1/JE and MIP-1 α were unable to evoke increases in intracellular calcium in murine monocytes treated with estrogen, alone or in combination with tamoxifen.
Conclusions: Our results show that estrogen suppresses the ability of monocytes to respond to certain chemokines, suggesting that estrogen exposure might decrease immune surveillance in tissues where the action of specific chemokines is involved. 相似文献
47.
48.
John P. McCarthy Marcas M. Bamman Janice M. Yelle Adrian D. LeBlanc Roger M. Rowe Michael C. Greenisen Stuart M. C. Lee Elisabeth R. Spector Suzanne M. Fortney 《European journal of applied physiology》1997,76(1):32-40
Resistance exercise has been suggested to increase blood volume, increase the sensitivity of the carotid baroreceptor cardiac reflex response (BARO), and decrease leg compliance, all factors that are expected to improve orthostatic tolerance. To further test these hypotheses, cardiovascular responses to standing and to pre-syncopal limited lower body negative pressure (LBNP) were measured in two groups of sedentary men before and after a 12-week period of either exercise (n = 10) or no exercise (control, n = 9). Resistance exercise training consisted of nine isotonic exercises, four sets of each, 3 days per week, stressing all major muscle groups. After exercise training, leg muscle volumes increased (P?0.05) by 4–14%, lean body mass increased (P = 0.00) by 2.0 (0.5)?kg, leg compliance and BARO were not significantly altered, and the maximal LBNP tolerated without pre-syncope was not significantly different. Supine resting heart rate was reduced (P = 0.03) without attenuating the heart rate or blood pressure responses during the stand test or LBNP. Also, blood volume (125I and 51Cr) and red cell mass were increased (P?0.02) by 2.8% and 3.9%, respectively. These findings indicate that intense resistance exercise increases blood volume but does not consistently improve orthostatic tolerance. 相似文献
49.
Platner JH Bennett LM Millikan R Barker MD 《Environmental and molecular mutagenesis》2002,39(2-3):102-107
The National Breast Cancer Coalition (NBCC) is a grassroots organization that represents breast cancer advocates and is committed to eradicating breast cancer. NBCC defines a breast cancer advocate as someone who has been personally affected by the disease (e.g., a breast cancer survivor, family member, or friend), represents a constituency, and is motivated to join the fight against the disease. One of the organization's goals is to ensure that breast cancer advocates have a seat at the table when decisions are made about breast cancer research and policy. To accomplish this goal, NBCC educates advocates so that they can participate in and make meaningful contributions to legislative, scientific, and regulatory decision-making bodies. In addition to creating educational opportunities for advocates, NBCC has spearheaded several initiatives designed to directly increase the quality and quantity of breast cancer research. NBCC has also played a major role in making funding available to breast cancer researchers. Two of NBCC's most notable programs include Project LEAD, an intensive science-training course for breast cancer advocates, and the Environmental Initiative, a collection of activities designed to improve research into the relationship between breast cancer and the environment. Breast cancer advocates trained by NBCC have partnered with the scientific community and individual scientists to improve the peer review, design, and implementation of breast cancer research. 相似文献
50.
Yoshitaka Iwasaki Judith Bartlett Kelly MacKay Jennifer Mactavish Janice Ristock 《Journal of community psychology》2008,36(6):702-722
This study reports key findings from a research project, which examined the stress and coping mechanisms of several nondominant groups of individuals. The groups were based in Winnipeg, Manitoba, Canada and included (a) Aboriginal individuals with diabetes, (b) individuals with disabilities, and (c) gays and lesbians. Our analyses of personal narratives and life stories have led to develop an interpretive map of findings that depicts mechanisms of how stress and coping operate. Specifically, the interpretive map consists of personal and structural stressors, meanings of stress, and personal and structural resources, as well as of two constructs termed intersectionality and social exclusion. Not only are nondominant voices and lived experiences recognized and incorporated into an emergent interpretive map, but this map also articulates the complex ways in which multiple identities intersect (i.e., intersectionality) and the realities of being excluded socioeconomically, culturally, and politically among nondominant groups (i.e., social exclusion). © 2008 Wiley Periodicals, Inc. 相似文献