首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   129篇
  免费   8篇
  国内免费   1篇
  2021年   2篇
  2020年   3篇
  2019年   4篇
  2018年   4篇
  2017年   7篇
  2016年   7篇
  2015年   11篇
  2014年   15篇
  2013年   6篇
  2012年   7篇
  2011年   11篇
  2010年   3篇
  2009年   4篇
  2008年   9篇
  2007年   5篇
  2006年   2篇
  2005年   5篇
  2004年   5篇
  2003年   1篇
  2002年   1篇
  2001年   4篇
  2000年   3篇
  1999年   3篇
  1998年   3篇
  1996年   2篇
  1995年   1篇
  1994年   1篇
  1986年   1篇
  1985年   4篇
  1982年   2篇
  1974年   1篇
  1971年   1篇
排序方式: 共有138条查询结果,搜索用时 31 毫秒
81.
82.
The objective of the present study was to identify mosquito fauna and to evaluate whether different light bulb colors influence the attraction of light traps in the Guapiaçu Ecological Reserve. Samples were obtained monthly during the period of February, 2012 to January, 2013. Centers for Disease Control (CDC) light traps with incandescent light bulbs and LED (ultraviolet, blue, green, and red) bulbs were utilized. In total, 8,170 specimens were captured, including 59 species. The presence of Anopheles nimbus (Theobald 1902) and Orthopodomyia fascipes Coquillet 1906 were recorded for the first time in the state of Rio de Janeiro. The green LED trap attracted the highest number of specimens and presented the highest diversity and mosquito average. The blue and green LED traps attracted the highest number of species. However, the differences between lights were not significant. The most common species were Coquillettidia juxtamansonia (Chagas 1907), Culex declarator Dyar and Knab 1906, and Culex ribeirensis Forattini and Sallum 1985.  相似文献   
83.

Objectives

In Peru, a country with constrained health resources, breast cancer control is characterized by late stage treatment and poor survival. To support breast cancer control in Peru, this study aims to determine the cost-effectiveness of different breast cancer control interventions relevant for the Peruvian context.

Methods

We performed a cost-effectiveness analysis (CEA) according to WHO-CHOICE guidelines, from a healthcare perspective. Different screening, early detection, palliative, and treatment interventions were evaluated using mathematical modeling. Effectiveness estimates were based on observational studies, modeling, and on information from Instituto Nacional de Enfermedades Neoplásicas (INEN). Resource utilizations and unit costs were based on estimates from INEN and observational studies. Cost-effectiveness estimates are in 2012 United States dollars (US$) per disability adjusted life year (DALY) averted.

Results

The current breast cancer program in Peru ($8,426 per DALY averted) could be improved through implementing triennial or biennial screening strategies. These strategies seem the most cost-effective in Peru, particularly when mobile mammography is applied (from $4,125 per DALY averted), or when both CBE screening and mammography screening are combined (from $4,239 per DALY averted). Triennially, these interventions costs between $63 million and $72 million per year. Late stage treatment, trastuzumab therapy and annual screening strategies are the least cost-effective.

Conclusions

Our analysis suggests that breast cancer control in Peru should be oriented towards early detection through combining fixed and mobile mammography screening (age 45-69) triennially. However, a phased introduction of triennial CBE screening (age 40-69) with upfront FNA in non-urban settings, and both CBE (age 40-49) and fixed mammography screening (age 50-69) in urban settings, seems a more feasible option and is also cost-effective. The implementation of this intervention is only meaningful if awareness raising, diagnostic, referral, treatment and basic palliative services are simultaneously improved, and if financial and organizational barriers to these services are reduced.  相似文献   
84.
A novel approach to the design of sensitive fluorescent probes for nucleic acids detection is proposed. Suitable modifications of tri- and pentamethine cyanine dyes in the polymethine chain and/or in the heterocyclic residues can result in a significant decrease in unbound dye fluorescence intensity and an increase in dye emission intensity in the presence of DNA compared to the unsubstituted dye. The sharp enhancement in the fluorescence intensity upon dye interaction with double-stranded DNA permits the application of the modified tri- and pentamethine dyes as fluorescent probes in double-stranded DNA detection in homogeneous assays.  相似文献   
85.
Spt6 is a multifunctional histone chaperone involved in the maintenance of chromatin structure during elongation by RNA polymerase II (Pol II). Spt6 has a tandem SH2 (tSH2) domain within its C terminus that recognizes Pol II C-terminal domain (CTD) peptides phosphorylated on Ser2, Ser5, or Try1 in vitro. Deleting the tSH2 domain, however, only has a partial effect on Spt6 occupancy in vivo, suggesting that more complex mechanisms are involved in the Spt6 recruitment. Our results show that the Ser2 kinases Bur1 and Ctk1, but not the Ser5 kinase Kin28, cooperate in recruiting Spt6, genome-wide. Interestingly, the Ser2 kinases promote the association of Spt6 in early transcribed regions and not toward the 3′ ends of genes, where phosphorylated Ser2 reaches its maximum level. In addition, our results uncover an unexpected role for histone deacetylases (Rpd3 and Hos2) in promoting Spt6 interaction with elongating Pol II. Finally, our data suggest that phosphorylation of the Pol II CTD on Tyr1 promotes the association of Spt6 with the 3′ ends of transcribed genes, independently of Ser2 phosphorylation. Collectively, our results show that a complex network of interactions, involving the Spt6 tSH2 domain, CTD phosphorylation, and histone deacetylases, coordinate the recruitment of Spt6 to transcribed genes in vivo.  相似文献   
86.
87.
88.
89.
90.
The role of sexual dimorphic adipose tissue fat accumulation in the development of insulin resistance is well known. However, whether vitamin A status and/or its metabolic pathway display any sex- or depot (visceral/subcutaneous)-specific pattern and have a role in sexual dimorphic adipose tissue development and insulin resistance are not completely understood. Therefore, to assess this, 5 weeks old Wistar male and female rats of eight from each sex were provided either control or diabetogenic (high fat, high sucrose) diet for 26 weeks. At the end, consumption of diabetogenic diet increased the visceral fat depots (p < 0.001) in the males and subcutaneous depot (p < 0.05) in the female rats, compared to their sex-matched controls. On the other hand, it caused adipocyte hypertrophy (p < 0.05) of visceral depot (retroperitoneal) in the females and subcutaneous depot of the male rats. Although vitamin A levels displayed sex- and depot-specific increase due to the consumption of diabetogenic diet, the expression of most of its metabolic pathway genes in adipose depots remained unaltered. However, the mRNA levels of some of lipid droplet proteins (perilipins) and adipose tissue secretory proteins (interleukins, lipocalin-2) did display sexual dimorphism. Nonetheless, the long-term feeding of diabetogenic diet impaired the insulin sensitivity, thus affected glucose clearance rate and muscle glucose-uptake in both the sexes of rats. In conclusion, the chronic consumption of diabetogenic diet caused insulin resistance in the male and female rats, but did not corroborate with sexual dimorphic adipose tissue fat accumulation or its vitamin A status.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号