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71.
Kalichman SC Eaton L Cain D Cherry C Pope H Kalichman M 《Journal of behavioral medicine》2006,29(5):401-410
People are living longer and healthier with HIV infection because of successful combination antiretroviral therapies. HIV treatment beliefs are often associated with sexual practices among people living with HIV/AIDS but these associations may depend on the HIV status of sex partners. In a sample of 158 HIV positive men and women who were receiving HIV treatments, we examined the association between HIV treatment beliefs, HIV transmission risk perceptions, medication adherence, viral load and engaging in unprotected intercourse with any sex partners and specifically with sex partners who were not HIV positive (non-concordant). Results showed having missed medications in the past two days and treatment-related beliefs were significantly associated with engaging in unprotected intercourse with all sex partners as well as non-concordant partners. However, multivariate models showed that only treatment beliefs were significantly associated with engaging in unprotected intercourse with non-concordant partners. These results extend past research by demonstrating that the HIV status of sex partners sets the context for whether prevention-related treatment beliefs are associated with HIV transmission risk behaviors among people living with HIV/AIDS. 相似文献
72.
Moira J. Sheehan Wojciech P. Pawlowski 《Proceedings of the National Academy of Sciences of the United States of America》2009,106(49):20989-20994
The ability of chromosomes to move across the nuclear space is essential for the reorganization of the nucleus that takes place in early meiotic prophase. Chromosome dynamics of prophase I have been studied in budding and fission yeasts, but little is known about this process in higher eukaryotes, where genomes and chromosomes are much larger and meiosis takes a longer time to complete. This knowledge gap has been mainly caused by difficulties in culturing isolated live meiocytes of multicellular eukaryotes. To study the nuclear dynamics during meiotic prophase in maize, we established a system to observe live meiocytes inside intact anthers. We found that maize chromosomes exhibited extremely dynamic and complex motility in zygonema and pachynema. The movement patterns differed dramatically between the two stages. Chromosome movements included rotations of the entire chromatin and movements of individual chromosome segments, which were mostly telomere-led. Chromosome motility was coincident with dynamic deformations of the nuclear envelope. Both, chromosome and nuclear envelope motility depended on actin microfilaments as well as tubulin. The complexity of the nuclear movements implies that several different mechanisms affect chromosome motility in early meiotic prophase in maize. We propose that the vigorous nuclear motility provides a mechanism for homologous loci to find each other during zygonema. 相似文献
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74.
John F Smyth Charlie Gourley Graeme Walker Melanie J MacKean Alan Stevenson Alistair R W Williams Awatif Al Nafussi Tzyvia Rye Ron Rye Moira Stewart Janet McCurdy Max Mano Nick Reed Tracey McMahon Paul Vasey Hani Gabra Simon P Langdon 《Clinical cancer research》2007,13(12):3617-3622
PURPOSE: To evaluate the efficacy of the aromatase inhibitor letrozole in preselected estrogen receptor (ER)-positive relapsed epithelial ovarian cancer patients and to identify markers that predict endocrine-sensitive disease. EXPERIMENTAL DESIGN: This was a phase II study of letrozole 2.5 mg daily until clinical or marker evidence of disease progression in previously treated ER-positive ovarian cancer patients with a rising CA125 that had progressed according to Rustin's criteria. The primary end point was response according to CA125 and response evaluation criteria in solid tumors (RECIST) criteria. Marker expression was measured by semiquantitative immunohistochemistry in sections from the primary tumor. RESULTS: Of 42 patients evaluable for CA125 response, 7 (17%) had a response (decrease of >50%), and 11 (26%) patients had not progressed (doubling of CA125) following 6 months on treatment. The median time taken to achieve the CA125 nadir was 13 weeks (range 10-36). Of 33 patients evaluable for radiological response, 3 (9%) had a partial remission, and 14 (42%) had stable disease at 12 weeks. Eleven patients (26%) had a PFS of >6 months. Subgroup analysis according to ER revealed CA125 response rates of 0% (immunoscore, 150-199), 12% (200-249), and 33% (250-300); P = 0.028, chi(2) for trend. Expression levels of HER2, insulin-like growth factor binding protein 5, trefoil factor 1, and vimentin were associated with CA125 changes on treatment. CONCLUSIONS: This is the first study of a hormonal agent in a preselected group of ER-positive ovarian cancer patients. A signature of predictive markers, including low HER2 expression, predicts response. 相似文献
75.
Much of the existing popular literature suggests that survival from life-threatening diseases encourages a process of self-transformation. Seventeen long-term survivors of metastatic cancer were interviewed about the impact of a life-threatening condition on their life stories. Contrary to the existing literature, which suggests such an event greatly transforms the individual, nearly all of those interviewed for this study framed their unusual recoveries as being largely unremarkable. Traditional North American cultural values, which normalize adversity, appear to bolster the participants' beliefs that one can have control over one's health and can even resist a recurrence of cancer. 相似文献
76.
The majority of individuals with asthma have mild disease, often in conjunction with allergic rhinitis and exercise-induced bronchoconstriction (EIB). Although health-related quality-of-life (HRQoL) is reduced in moderate to severe asthma and allergic rhinitis, little is known about the effect of mild asthma, mild allergic rhinitis, and EIB on HRQoL outcomes. The objective of this study was to determine the effect of mild asthma, allergic rhinitis, and EIB on HRQoL. A cross-sectional study was conducted of 160 adolescent athletes participating in a screening program to detect EIB. Generic HRQoL was assessed with the teen version of the pediatric quality-of-life inventory (PedsQL). Prior diagnoses of asthma, allergic rhinitis, and EIB, and current symptoms of dyspnea during exercise and asthma, were recorded. Lung function and the presence of EIB were determined by spirometry before and after an exercise challenge test. Adolescent athletes with a prior physician diagnosis of asthma had a lower HRQoL scale summary score (P<0.01) and lower physical functioning, emotional functioning, and school functioning domain scores (P values, 0.01-0.02) in comparison to adolescent athletes with no prior diagnosis of these disorders. Athletes with a prior diagnosis of asthma reported dyspnea during exercise more frequently than did those without asthma (P<0.001). Adolescent athletes with dyspnea during exercise had a lower scale summary score, and lower physical functioning, general well-being, and emotional functioning domain scores (P values, 0.02-0.03). These data show that mild asthma and dyspnea without asthma significantly affect HRQoL. Symptoms of dyspnea during exercise are common in asthma and are associated with lower HRQoL. The clinical significance of these differences in HRQoL is unclear. 相似文献
77.
78.
Humorally mediated posttransplantation septal capillary injury syndrome as a common form of pulmonary allograft rejection: a hypothesis 总被引:4,自引:0,他引:4
Magro CM Deng A Pope-Harman A Waldman WJ Bernard Collins A Adams PW Kelsey M Ross P 《Transplantation》2002,74(9):1273-1280
BACKGROUND: Cellular immunity is the reputed mechanism of lung allograft failure. Humoral immunity is not a commonly recognized pathway. MATERIAL AND METHODS: We describe 22 patients who developed a posttransplantation septal capillary injury syndrome in the absence of panel-reactive antibodies. Factor VIII levels served as an index of microvascular injury. Routine light microscopic studies were performed in a total of 73 biopsies; 54 biopsy specimens were analyzed for deposition of C1q, C4d, C5b-9, and immunoglobulin (IgG, IgM, and IgA). Indirect immunofluorescent testing to assess for antiendothelial cell antibodies was performed using patient serum and human pulmonary microvascular endothelial cell cultures as substrate. Control samples were based on patients who were clinically well at the time of the biopsy. RESULTS: All presented with a deterioration in respiratory function. All patients had elevated factor VIII levels; the levels were significantly greater compared with pretransplantation baseline values (P =<0.03). The biopsy specimens were remarkable for septal capillary necrosis with significant septal capillary deposition of C1q, C3, C4d, and/or C5b-9 along with immunoglobulin, including IgG, with variable endothelial cell localization. The degree of septal capillary necrosis was significantly less in posttransplantation patients who were clinically doing well ( P<0.0001) as was the degree of C1q, C3, C4d, and C5b-9 ( P<0.05). Indirect antiendothelial cell antibody studies were positive in most patients. Treatment interventions included plasmapheresis, resulting in functional improvement: the postpheresis biopsy specimens showed a reduction in both the degree of septal capillary injury (P <0.0003) and the amount of C1q, C3, C4d, and C5b-9 deposition (P <0.05). CONCLUSIONS: Septal capillary injury accompanied by direct and indirect immunofluorescent evidence of humoral immunity is a frequent finding on transbronchial biopsies. The findings suggest that humoral immunity to endothelial-based alloantigen is a common occurrence in lung grafts and may be a critical factor in chronic graft dysfunction. 相似文献
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