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21.
Vaccines were prepared from cells of primary spontaneous mammary tumors (MT) of RIII/Imr, GR/Imr, C3H/Imr, A/Imr, and C3HfC57BL/Imr mice. Each vaccine was used to immunize "murine mammary tumor virus (MuMTV)-free" BALB/c/Imr and C57BL/Imr mice before challenge with infectious RIII-MuMTV, GR-MuMTV, C3H-MuMTV, and A-MuMTV. RIII-MT and C3H-MT cells protected mice against tumorigenesis by all four MuMTV's; GR-MT cells protected against all but the RIII-MuMTV challenge; A-MT cells were ineffective against challenge by all four MuMTV's and significantly enhanced development of A-MuMTV-induced tumors. The activity of the C3H-MT cells was not seen when C3HfC57BL cells, free of the standard C3H-MuMTV, were used. The same cell vaccines were inoculated into the five donor strains of mice in attempts to prevent spontaneous MT in these high-incidence strains, which are naturally infected with MuMTV at birth. None of the vaccines prevented tumorigenesis in these mouse strains although delays in the appearance of tumors were observed in RIII and GR mice inoculated with either isologous MT cells or C3Hf-MT cells. The role of viral antigens acting alone or in concert with cellular antigens is discussed.  相似文献   
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To overcome the challenge of obtaining accurate data on community food retail, we developed an innovative tool to automatically capture food retail data from Google Earth (GE). The proposed method is relevant to non-commercial use or scholarly purposes. We aimed to test the validity of web sources data for the assessment of community food retail environment by comparison to ground-truth observations (gold standard). A secondary aim was to test whether validity differs by type of food outlet and socioeconomic status (SES). The study area included a sample of 300 census tracts stratified by SES in two of the largest cities in Brazil, Rio de Janeiro and Belo Horizonte. The GE web service was used to develop a tool for automatic acquisition of food retail data through the generation of a regular grid of points. To test its validity, this data was compared with the ground-truth data. Compared to the 856 outlets identified in 285 census tracts by the ground-truth method, the GE interface identified 731 outlets. In both cities, the GE interface scored moderate to excellent compared to the ground-truth data across all of the validity measures: sensitivity, specificity, positive predictive value, negative predictive value and accuracy (ranging from 66.3 to 100%). The validity did not differ by SES strata. Supermarkets, convenience stores and restaurants yielded better results than other store types. To our knowledge, this research is the first to investigate using GE as a tool to capture community food retail data. Our results suggest that the GE interface could be used to measure the community food environment. Validity was satisfactory for different SES areas and types of outlets.  相似文献   
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Lasers in Medical Science - Physical activity raises body temperature. However, the literature does not contain studies about whether the employment of hotobiomodulation (PMB) could significantly...  相似文献   
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The esophageal cancer surgery is a complex procedure with elevated rates of both morbidity and mortality, which is why, in order to achieve adequate results, it should be performed in high volume centers, where complete multidisciplinary support is available and recent clinical guidelines are applied. We describe the initial experience and the technique of “tubeless” esophagectomy where esophageal resection and mediastinal lymphadenectomy are performed and no drains nor tubes of any kind are placed, with the aim to decrease the level of surgical aggression, enhance the postoperative comfort and accelerate the patient?s recovery.  相似文献   
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Quality of Life Research - As people around the world are facing the Covid-19 outbreak, their perception of oral health problems could be changed. This study aimed to evaluate the immediate effects...  相似文献   
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Upregulation of the inducible gene products MICA (human) and Rae-1 (mouse) may promote tumor surveillance and autoimmunity by engaging the activating receptor NKG2D on natural killer (NK) cells and T cells. Nevertheless, sustained expression of MICA by tumors can also elicit NKG2D downregulation, perhaps indicating 'immunoevasion'. Investigating this paradox, we report here that constitutive Rae-1epsilon transgene expression in normal epithelium elicited local and systemic NKG2D downregulation, generalized but reversible defects in NK cell-mediated cytotoxicity and mild CD8(+) T cell defects. The extent of NKG2D downregulation correlated well with the incidence and progression of cutaneous carcinogenesis, emphasizing the utility of NKG2D as a marker of tumor resistance. Thus, NKG2D engagement is a natural mediator of immunosurveillance, which can be compromised by locally sustained ligand expression but potentially restored by innate immune activation.  相似文献   
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目的:评价单一穴位治疗急性腰扭伤的治疗效果.方法:根据统一的诊断标准,在多个临床中心进行随机对照研究.全部病例320例经随机数字表法分为针刺后溪穴观察组和针刺腰痛点对照组.对患者的疼痛程度分别由医师和患者进行评分.结果:治疗2个疗程后,观察组和对照组近期有效率分别为89.4%和82.5%,远期有效率分别为95.6%和93.5%.经Ridit分析,近期疗效差异有统计意义(P<0.05),远期疗效差异无统计意义(P>0.05).结论:针刺单一穴位治疗急性腰扭伤疗效确切,取穴简便,后溪穴疗效好于腰痛点.  相似文献   
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