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71.
基于空间分析预测钉螺分布的气温指标研究   总被引:4,自引:2,他引:4  
目的探讨钉螺分布与气温的定量关系,为全球气候变暖与南水北调钉螺能否北移提供理论基础。方法收集多年来的年平均最低气温、1月平均最低气温、年平均气温、1月平均气温、年平均最高气温,按1km网格匹配气温数据,在GIS支持下,将空间分布的气温数据与中国血吸虫病流行县分布图进行空间统计分析,并比较不同气温与钉螺分布的吻合程度。结果钉螺分布区的累年平均最低气温的95%可信区间为(4.3~18.1℃)、累年1月平均最低气温的为(-4.6~9.2℃)、累年平均气温的为(9.4~21.1℃)、累年1月平均气温的为(0.9~12.4℃)、累年平均最高气温的为(16.2~25.6℃),其中累年1月平均气温与钉螺的分布拟合最好。结论1月平均气温是预测钉螺分布的较好指标。  相似文献   
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ContextThe comfort of patients with cancer near the end of life (EOL) is often undermined by unnecessary and burdensome treatments. There is a need for more research examining racial disparities in EOL care, especially in regions with a history of racial discrimination.ObjectivesTo examine whether black adults received more burdensome EOL care than white adults in a population-based data set of cancer decedents in Louisiana, a state with a history of slavery and long-standing racial disparities.MethodsThis was a retrospective analysis of EOL care from the Research Action for Health Network (REACHnet), a regional Patient-Centered Outcomes Research Institute-funded database. The sample consisted of 875 white and 415 black patients with metastatic cancer who died in Louisiana from 2011 to 2017. We used logistic regression to examine whether race was associated with five indicators of burdensome care in the last 30 days of life: chemotherapy use, inpatient hospitalization, intensive care unit admission, emergency department (ED) admission, and mechanical ventilation.ResultsMost patients (85.0%) received at least one indicator of burdensome care: hospitalization (76.5%), intensive care unit admission (44.1%), chemotherapy (29.1%), mechanical ventilation (23.0%), and ED admission (18.3%). Odds ratios (ORs) indicated that black individuals were more likely than white individuals to be hospitalized (OR = 1.66; 95% CI = 1.21–2.28; P = 0.002) or admitted to the ED (OR = 1.57; 95% CI = 1.16–2.13; P = 0.004) during their last month of life.ConclusionFindings have implications for informing health care decision making near the EOL for patients, families, and clinicians, especially in regions with a history of racial discrimination and disparities.  相似文献   
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Increased germ cell apoptosis is related to oxidative DNA damage; therefore, we investigated whether there was a significant change in apurinic/apyrimidinic endonuclease (APE) in varicoceles. Experimental varicoceles were created by partial ligation of the left renal vein of adult male Sprague-Dawley rats, which were sacrificed at 1, 3 and 6 weeks after varicocele creation. Testicular tissues were sampled for TUNEL, Western blotting and immunohistochemistry. There was a significant increase in apoptotic germ cells in the ipsilateral testes 6 weeks after varicocele creation. Increased activation of p53, Bax and cleaved caspase-3 in the left testes was also noted. APE increased activation until 3 weeks after varicocele creation, and then decreased at 6 weeks after varicocele surgery. The spermatocytes were immunostained for both 8-hydroxy-2′-deoxyguanosine and APE, but the spermatogonia revealed only APE immunopositivity in the defective tubules. These results suggest that repression of APE is an underlying mechanism of augmented p53-dependent apoptosis in varicocele-induced rat testes and that remaining APE in the spermatogonia plays a decisive role in regaining testicular spermatogenic function after varicocelectomy.  相似文献   
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Immunostimulatory DNA ameliorates experimental and spontaneous murine colitis   总被引:23,自引:0,他引:23  
BACKGROUND & AIMS: Impaired mucosal barrier, cytokine imbalance, and dysregulated CD4(+) T cells play important roles in the pathogenesis of experimental colitis and human inflammatory bowel disease. Immunostimulatory DNA sequences (ISS-DNA) and their synthetic oligonucleotide analogs (ISS-ODNs) are derived from bacterial DNA, are potent activators of innate immunity at systemic and mucosal sites, and can rescue cells from death inflicted by different agents. We hypothesized that these combined effects of ISS-DNA could inhibit the damage to the colonic mucosa in chemically induced colitis and thereby limit subsequent intestinal inflammation. METHODS: The protective and the anti-inflammatory effect of ISS-ODN administration were assessed in dextran sodium sulfate-induced colitis and in 2 models of hapten-induced colitis in Balb/c mice. Similarly, these effects of ISS-ODN were assessed in spontaneous colitis occurring in IL-10 knockout mice. RESULTS: In all models of experimental and spontaneous colitis examined, ISS-ODN administration ameliorated clinical, biochemical, and histologic scores of colonic inflammation. ISS-ODN administration inhibited the induction of colonic proinflammatory cytokines and chemokines and suppressed the induction of colonic matrix metalloproteinases in both dextran sodium sulfate- and hapten-induced colitis. CONCLUSIONS: As the colon is continuously exposed to bacterial DNA, these findings suggest a physiologic, anti-inflammatory role for immunostimulatory DNA in the GI tract. Immunostimulatory DNA deserves further evaluation for the treatment of human inflammatory bowel disease.  相似文献   
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