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The implication of MALT1 gene in the pathogenesis of primary cutaneous marginal zone B-cell lymphomas (PCMZL) has been a matter of controversy. We examined the presence of MALT1 translocations in a series of 23 PCMZL. FISH assay with a MALT1 dual color break apart translocation probe revealed the absence of MALT1 translocations in all cases. 相似文献
94.
Vision in natural situations is different from the paradigms generally used to study vision in the laboratory. In natural vision, stimuli usually appear in a receptive field as the result of saccadic eye movements rather than suddenly flashing into view. The stimuli themselves are rich with meaningful and recognizable objects rather than simple abstract patterns. In this study we examined the sensitivity of neurons in macaque area V1 to saccades and to complex background contexts. Using a variety of visual conditions, we find that natural visual response patterns are unique. Compared with standard laboratory situations, in more natural vision V1 responses have longer latency, slower time course, delayed orientation selectivity, higher peak selectivity, and lower amplitude. Furthermore, the influences of saccades and background type (complex picture vs. uniform gray) interact to give a distinctive, and presumably more natural, response pattern. While in most of the experiments natural images were used as background, we find that similar synthetic unnatural background stimuli produce nearly identical responses (i.e., complexity matters more than "naturalness"). These findings have important implications for our understanding of vision in more natural situations. They suggest that with the saccades used to explore complex images, visual context ("surround effects") would have a far greater effect on perception than in standard experiments with stimuli flashed on a uniform background. Perceptual thresholds for contrast and orientation should also be significantly different in more natural situations. 相似文献
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Pérez-Fidalgo JA Pimentel P Caballero A Bermejo B Barrera JA Burgues O Martinez-Ruiz F Chirivella I Bosch A Martínez-Agulló A Lluch A 《Breast (Edinburgh, Scotland)》2011,20(6):548-554
Background
Resection of intact primary tumor is controversial in metastatic breast cancer patients. The aim of this study is to review the impact of surgical resection of primary tumor on overall survival and to assess the role of timing of surgery on survival rates.Methods
208 patients with metastatic breast cancer diagnosed between 1982 and 2005 in the Hospital Clinico of Valencia (Spain) were analysed. Exclusion criteria were age >80, PS 3–4, Charlson score 3 or follow-up < 90 days. 123 of these underwent surgery and 85 did not. In order to assess the role of timing, the "surgery" cohort was divided into two sub-groups: "before" (n = 78) or "after" (n = 45) diagnosis of disseminated disease.Results
In the surgery group, patients underwent mastectomy with axillary dissection (82.9%), without axillary dissection (8.9%) and conservative surgery (8.1%). After a median follow-up of 29.68 months, median OS in the "surgery" and the "non-surgery" groups were, 40.4 and 24.3 months. Removal of the primary tumor therefore had a significant positive impact on survival rates (p < 0.001). Benefits of surgery were observed mainly in patients with visceral disease (p = 0.005); no statistical differences were found in those with bone disease (p = 0.79). Univariate analysis for overall survival (OS) identified surgery, performance status, clinical T stage, hormone receptors and number and type of metastases as variables that impacted on survival. In the multivariate test, only resection of primary tumor and estrogen receptors maintained statistical significance, surgery having a protective effect with an HR 0.52 (95% CI 0.35–0.77). No differences in survival were found between the two sub-groups according to the timing of surgery: "before" vs "after"(p = 0.996).Conclusions
Resection of primary tumor should be considered not only as a palliative or preventive strategy but also as an approach that possibly contributes to the control of the disease in selected patients. 相似文献96.
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Noyola DE Malacara-Alfaro O Lima-Rogel V Torres-Montes A 《Salud pública de México》2006,48(2):151-154
OBJECTIVE: To determine the seroprevalence of syphilis in pregnant women. METHODS: A seroepidemiologic survey was conducted in 1857 women giving birth at a general hospital in the city of San Luis Potosi, Mexico. RESULTS: Five women (0.27%) were diagnosed with syphilis at the time of delivery. Maternal factors associated with a greater likelihood of syphilis included older age, a higher number of pregnancies and living out of wedlock. CONCLUSIONS: The number of new bhorns exposed to syphilis during pregnancy in San Luis Potosi is underestimated. The results of this study support the need to identify syphilis in infected mothers at the time of delivery. 相似文献
99.
Despite having achieved an average life expectancy of 75 years, much the same as that of more developed countries, Mexico entered the 21st century with a health system marred by its failure to offer financial protection in health to more than half of its citizens; this was both a result and a cause of the social inequalities that have marked the development process in Mexico. Several structural limitations have hampered performance and limited the progress of the health system. Conscious that the lack of financial protection was the major bottleneck, Mexico has embarked on a structural reform to improve health system performance by establishing the System of Social Protection in Health (SSPH), which has introduced new financial rules and incentives. The main innovation of the reform has been the Seguro Popular (Popular Health Insurance), the insurance-based component of the SSPH, aimed at funding health care for all those families, most of them poor, who had been previously excluded from social health insurance. The reform has allowed for a substantial increase in public investment in health while realigning incentives towards better technical and interpersonal quality. This paper describes the main features and initial results of the Mexican reform effort, and derives lessons for other countries considering health-system transformations under similarly challenging circumstances. 相似文献
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