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31.
32.
Farah Ahmad Syeda F. Kabir Nabila H. Purno Saima Islam Ophira Ginsburg 《Health care for women international》2017,38(4):334-343
In many low- and middle-income countries, breast cancer survival is low. Reasons for this are multifactorial, but delayed presentation for care is a common theme. In this survey study with 100 urban Bangladeshi women, we examined the role of socioeconomic and sociocultural factors on their likelihood to seek breast care from a family physician. In our multivariate model, a woman's age and education significantly predicted her likelihood to see a physician. Sociocultural aspects (e.g., concerns about time commitment of family members, personal household obligations) were significant at bivariate level. Findings are discussed in relation to practice, policy, and research. 相似文献
33.
Theory: Assessment of clinical competence is a complex cognitive task with many mental demands often imposed on raters unintentionally. We were interested in whether this burden might contribute to well-described limitations in assessment judgments. In this study we examine the effect on indicators of rating quality of asking raters to (a) consider multiple competencies and (b) attend to multiple issues. In addition, we explored the cognitive strategies raters engage when asked to consider multiple competencies simultaneously. Hypotheses: We hypothesized that indications of rating quality (e.g., interrater reliability) would decline as the number of dimensions raters are expected to consider increases. Method: Experienced faculty examiners rated prerecorded clinical performances within a 2 (number of dimensions) × 2 (presence of distracting task) × 3 (number of videos) factorial design. Half of the participants were asked to rate 7 dimensions of performance (7D), and half were asked to rate only 2 (2D). The second factor involved the requirement (or lack thereof) to rate the performance of actors participating in the simulation. We calculated the interrater reliability of the scores assigned and counted the number of relevant behaviors participants identified as informing their ratings. Second, we analyzed data from semistructured posttask interviews to explore the rater strategies associated with rating under conditions designed to broaden raters' focus. Results: Generalizability analyses revealed that the 2D group achieved higher interrater reliability relative to the 7D group (G = .56 and .42, respectively, when the average of 10 raters is calculated). The requirement to complete an additional rating task did not have an effect. Using the 2 dimensions common to both groups, an analysis of variance revealed that participants who were asked to rate only 2 dimensions identified more behaviors of relevance to the focal dimensions than those asked to rate 7 dimensions: procedural skill = 36.2%, 95% confidence interval (CI) [32.5, 40.0] versus 23.5%, 95% CI [20.8, 26.3], respectively; history gathering = 38.6%, 95% CI [33.5, 42.9] versus 24.0%, 95% CI [21.1, 26.9], respectively; ps < .05. During posttask interviews, raters identified many sources of cognitive load and idiosyncratic cognitive strategies used to reduce cognitive load during the rating task. Conclusions: As intrinsic rating demands increase, indicators of rating quality decline. The strategies that raters engage when asked to rate many dimensions simultaneously are varied and appear to yield idiosyncratic efforts to reduce cognitive effort, which may affect the degree to which raters make judgments based on comparable information. 相似文献
34.
E. Koren J. Lipkin A. Klar E. Hershkovitz I. Ginsburg R. Kohen 《Journal of inherited metabolic disease》2009,32(5):651-659
It has been suggested that the very low incidence of atherosclerosis in glycogen storage disease type Ia (GSD Ia) subjects
might be attributed to elevated levels of uric acid, one of the potent low-molecular-weight antioxidants found in plasma.
The present communication describes a use of two analytical methods—cyclic voltammetry and ferric reducing ability of plasma—and
also two chemiluminescence methods to evaluate the total oxidant-scavenging capacities (TOSC) of plasma from GSD Ia patients.
Our results verified the elevation of TOSC in GSD Ia patients and we propose the inclusion of luminescence and cyclic voltammetry
assays as reliable methods for estimating TOSC in a variety of clinical disorders. Our findings with the cyclic voltammetry
method add support to the assumption that the elevated uric acid levels might be the main contributor to plasma antioxidant
capacity and possible protection against atherosclerosis. 相似文献
35.
Minasian LM; Szatrowski TP; Rosenblum M; Steffens T; Morrison ME; Chapman PB; Williams L; Nathan CF; Houghton AN 《Blood》1994,83(1):56-64
Hemorrhagic tumor necrosis is an inflammatory event that leads to selective destruction of malignant tissues, with both potentially toxic and beneficial consequences. A pilot clinical trial was undertaken combining tumor necrosis factor-alpha (TNF-alpha) with the monoclonal antibody R24 (MoAb R24) against GD3 ganglioside in patients with metastatic melanoma. Patients received MoAb R24 to recruit leukocytes to the tumor followed by low doses of recombinant TNF-alpha to activate leukocytes. Eight patients were treated and seven patients had mild toxicity. One patient with extensive metastatic melanoma developed tumor lysis syndrome within hours after treatment with almost complete necrosis of bulky tumors in multiple visceral sites. To our knowledge, this is the first documented case of hemorrhagic tumor necrosis in a patient with metastatic cancer in multiple visceral sites. 相似文献
36.
Home therapy with porcine factor VIIIC was safe and effective when administered to five hemophilic patients over periods of 8 1/2, 6, 4, 3 1/2, and 2 years. No significant transfusion reactions occurred. Before treatment with porcine factor VIIIC, all five had high-level, high- responding anti-human VIIIC inhibitors initially lacking anti-porcine factor VIIIC activity. Although specific anti-porcine VIIIC inhibitors arose in all patients, these were generally transient, and only one patient became refractory to treatment. We believe that porcine factor VIIIC is the treatment of choice in patients whose inhibitors do not cross-react. All five patients lost their original anti-human VIIIC inhibitors after starting treatment with porcine VIIIC, permitting the reintroduction of human VIIIC in three of them. There has been no recurrence of anti-human VIIIC inhibitor activity during 2 to 3 years of regular treatment with human VIIIC in these patients. This suggests that tolerance to human VIIIC has arisen as a result of treatment with porcine VIIIC. Porcine VIIIC may have a role in the desensitization of some factor VIIIC inhibitor patients. 相似文献
37.
Factor V Quebec revisited 总被引:2,自引:5,他引:2
Factor V Quebec has been described as a bleeding disorder that exhibits an autosomal dominant inheritance pattern and presents severe bleeding after trauma. Two members of a fourth-generation (IV.13 and IV.15) Canadian family have been studied in detail and are the subject of this report. Their clinical presentations and histories have been described previously (Tracy et al: J Clin Invest 74:1221, 1984). Persistent abnormalities include mild thrombocytopenia and defective platelet factor V. Plasma factor V is present at near normal concentration and is fully functional. Thus, the bleeding diathesis appears to reflect the absence of platelet factor V activity. The recent report (Hayward et al: Blood 84:110a, 1994 [suppl, abstr]) of multimerin deficiency in these individuals led us to reevaluate these patients. Western blot analyses of platelet lysates developed with a variety of monoclonal antibodies show that the alpha-granule proteins, fibrinogen, von Willebrand factor, factor V and osteonectin are decreased in concentration and significantly degraded in the platelets of these patients. Thrombospondin, while not degraded, is substantially decreased. In contrast, platelet factor 4 and beta-thromboglobulin do not appear to be affected. These observations suggest that the alpha- granules are correctly assembled but the contents are subsequently subjected to proteolytic degradation. The results indicate that factor V Quebec disorder is probably associated with a generalized defect that leads to degradation of most proteins of the alpha-granules. 相似文献
38.
Abnormal function of the bone marrow microenvironment in chronic myelogenous leukemia: role of malignant stromal macrophages 总被引:7,自引:4,他引:7
The bone marrow microenvironment supports and regulates the proliferation and differentiation of hematopoietic cells. Dysregulated hematopoiesis in chronic myelogenous leukemia (CML) is caused, at least in part, by abnormalities in CML hematopoietic progenitors leading to altered interactions with the marrow microenvironment. The role of the microenvironment itself in CML has not been well characterized. We examined the capacity of CML stroma to support the growth of long-term culture-initiating cells (LTC-IC) obtained from normal and CML marrow. The growth of normal LTC-IC on CML stroma was significantly reduced compared with normal stroma. This did not appear to be related to abnormal production of soluble factors by CML stroma because normal LTC- IC grew equally well in Transwells above CML stroma as in Transwells above normal stroma. In addition, CML and normal stromal supernatants contained similar quantities of both growth-stimulatory (granulocyte colony-stimulating factor (CSF), interleukin-6, stem cell factor, granulocyte-macrophage CSF, and interleukin-1 beta) and growth- inhibitory cytokines (transforming growth factor-beta, macrophage inflammatory protein-1 alpha, and tumor necrosis factor-alpha). The relative proportion of different cell types in CML and normal stroma was similar. However, polymerase chain reaction and fluorescence in situ hybridization studies showed the presence of bcr-abl-positivo cells in CML stroma, which were CD14+ stromal macrophages. To assess the effect of these malignant macrophages on stromal function, CML and normal stromal cells were separated by fluorescence-activated cell sorting into stromal mesenchymal cell (CD14-) and macrophage (CD14+) populations. CML and normal CD14- cells supported the growth of normal LTC-IC equally well. However, the addition of CML macrophages to normal or CML CD14- mesenchymal cells resulted in impaired progenitor support. This finding indicates that the abnormal function of CML bone marrow stroma is related to the presence of malignant macrophages. In contrast to normal LTC-IC, the growth of CML LTC-IC on allogeneic CML stromal layers was not impaired and was significantly better than that of normal LTC-IC cocultured with the same CML stromal layers. These studies demonstrate that, in addition to abnormalities in CML progenitors themselves, abnormalities in the CML marrow microenvironment related to the presence of malignant stromal macrophages may contribute to the selective expansion of leukemic progenitors and suppression of normal hematopoiesis in CML. 相似文献
39.
40.
Asaf Sol Ofir Ginesin Stella Chaushu Laila Karra Shunit Coppenhagen-Glazer Isaac Ginsburg Gilad Bachrach 《Infection and immunity》2013,81(10):3577-3585
Host defense peptides are immediate responders of the innate immunity that express antimicrobial, immunoregulatory, and wound-healing activities. Neutrophils are a major source for oral host defense peptides, and phagocytosis by neutrophils is a major mechanism for bacterial clearance in the gingival tissue. Dysfunction of or reduction in the numbers of neutrophils or deficiency in the LL-37 host defense peptide was each previously linked with proliferation of oral Aggregatibacter actinomycetemcomitans which resulted in an aggressive periodontal disease. Surprisingly, A. actinomycetemcomitans shows resistance to high concentrations of LL-37. In this study, we demonstrated that submicrocidal concentrations of LL-37 inhibit biofilm formation by A. actinomycetemcomitans and act as opsonins and agglutinins that greatly enhance its clearance by neutrophils and macrophages. Improved uptake of A. actinomycetemcomitans by neutrophils was mediated by their opsonization with LL-37. Enhanced phagocytosis and killing of A. actinomycetemcomitans by murine macrophage-like RAW 264.7 cells were dependent on their preagglutination by LL-37. Although A. actinomycetemcomitans is resistant to the bactericidal effect of LL-37, our results offer a rationale for the epidemiological association between LL-37 deficiency and the expansion of oral A. actinomycetemcomitans and indicate a possible therapeutic use of cationic peptides for host defense. 相似文献