全文获取类型
收费全文 | 214篇 |
免费 | 9篇 |
国内免费 | 54篇 |
出版年
2023年 | 1篇 |
2022年 | 6篇 |
2021年 | 11篇 |
2020年 | 10篇 |
2019年 | 5篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 10篇 |
2015年 | 13篇 |
2014年 | 20篇 |
2013年 | 18篇 |
2012年 | 15篇 |
2011年 | 23篇 |
2010年 | 11篇 |
2009年 | 3篇 |
2008年 | 12篇 |
2007年 | 8篇 |
2006年 | 10篇 |
2005年 | 13篇 |
2004年 | 12篇 |
2003年 | 11篇 |
2002年 | 4篇 |
2001年 | 6篇 |
2000年 | 2篇 |
1999年 | 7篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 2篇 |
1994年 | 2篇 |
1993年 | 8篇 |
1992年 | 9篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1985年 | 1篇 |
排序方式: 共有277条查询结果,搜索用时 15 毫秒
91.
92.
93.
94.
Chunyu Zheng Guanghua Wang Junjie Liu Changchun Song Hongxing Gao Xiaobing Liu 《Microbial ecology》2013,65(3):616-625
To obtain genetic information and to evaluate the composition of T4-type bacteriophage (phage) communities in wetlands, environmental soil and water DNAs were obtained from two natural wetlands dominated by Carex lasiocarpa and Deyeuxia angustifolia plant species, and a neighboring paddy field in Sanjiang plain of northeast China. The biomarker gene of g23, which encodes the major capsid protein of T4-type phages, was amplified with primers MZIA1bis and MZIA6, and the PCR products were cloned and sequenced. In total, 96 and 50 different g23 clones were obtained from natural wetlands and a paddy field, respectively. A larger number of clones with low levels of identity to known sequences were found in water than in soil both in the natural wetlands and the paddy field, suggesting that many of T4-type phages in wetland water and paddy floodwater in Sanjiang plain are uncharacterized. Phylogenetic analyses showed that the g23 clones in natural wetlands, irrespective of water and soil, were distinctly different from those in marine waters, lake waters, and upland black soils, but were similar to those in paddy fields. The UniFrac analysis of g23 assemblages indicated that T4-type phage community compositions were different between soils and waters, and also were different between the natural wetlands and the paddy field. In general, the global analysis of g23 clone assemblages demonstrated that T4-type phage community compositions were different among natural wetlands, marines, lakes, paddy fields, and upland black soils. 相似文献
95.
Biao He Zuosheng Li Fanli Yang Junfeng Zheng Ye Feng Huancheng Guo Yingying Li Yiyin Wang Nan Su Fuqiang Zhang Quanshui Fan Changchun Tu 《PloS one》2013,8(4)
Bats are reservoir animals harboring many important pathogenic viruses and with the capability of transmitting these to humans and other animals. To establish an effective surveillance to monitor transboundary spread of bat viruses between Myanmar and China, complete organs from the thorax and abdomen from 853 bats of six species from two Myanmar counties close to Yunnan province, China, were collected and tested for their virome through metagenomics by Solexa sequencing and bioinformatic analysis. In total, 3,742,314 reads of 114 bases were generated, and over 86% were assembled into 1,649,512 contigs with an average length of 114 bp, of which 26,698 (2%) contigs were recognizable viral sequences belonging to 24 viral families. Of the viral contigs 45% (12,086/26,698) were related to vertebrate viruses, 28% (7,443/26,698) to insect viruses, 27% (7,074/26,698) to phages and 95 contigs to plant viruses. The metagenomic results were confirmed by PCR of selected viruses in all bat samples followed by phylogenetic analysis, which has led to the discovery of some novel bat viruses of the genera Mamastrovirus, Bocavirus, Circovirus, Iflavirus and Orthohepadnavirus and to their prevalence rates in two bat species. In conclusion, the present study aims to present the bat virome in Myanmar, and the results obtained further expand the spectrum of viruses harbored by bats. 相似文献
96.
目的检测骨肉瘤中血管生成拟态(vasculogenic mimicry,VM)和缺氧诱导因子-1α(HIF-1α)的关系及临床意义,旨在探寻影响骨肉瘤进展及预后的有效指标。方法采用CD34和PAS套染法检测108例骨肉瘤及28例骨软骨瘤中VM、微血管密度(Microvessel density,MVD)及HIF-1α表达水平差异,并分析其与骨肉瘤患者临床病理因素及5年存活率之间的关系。结果骨肉瘤组织中VM、HIF-1α过表达及MVD≥22的阳性率分别为62.96%(68/108)、57.41%(62/108)和58.33%(63/108),骨软骨瘤中分别为0%(0/28)、32.14%(9/28)和28.57%(8/28)(P<0.05);VM、HIF-1α过表达及MVD与骨肉瘤分级、远处转移及软组织浸润和Enneking分期有关(P<0.05),与患者年龄、性别、部位、肿瘤大体、组织学类型和直径无关(P>0.05);骨肉瘤中VM、HIF-1α过表达与MVD之间呈正相关(P<0.05);VM阳性、HIF-1α过表达及MVD≥22组患者5年存活率分别为8.82%(6/68)、8.06%(5/62)和3.17%(2/63);VM阴性、HIF-1α低表达及MVD<22组分别为87.5%(35/40)、78.26%(36/46)和86.67%(39/45)(P<0.05);Cox多因素分析提示VM、HIF-1α、MVD、远处转移、软组织浸润和Enneking分期是影响骨肉瘤患者预后的独立危险因素(P<0.05)。结论 VM可能是判断骨肉瘤预后的新指标,联合检测VM、HIF-1α及MVD对骨肉瘤的侵袭、转移及预后判断有重要意义。 相似文献
97.
98.
99.
Background
Stromal cell-derived factor-1(SDF-1) is a chemotactic and angiogenic factor that mediates the repair of various tissues. As macrophages are important contributors to ischemic kidney injury, we examine the role of SDF-1 in a rodent model of ischemia-reperfusion (I/R) injury.Methods
Male wild-type (WT) (C57BL/6) mice were subjected to bilateral I/R injury or sham operation in the presence or absence of macrophage depletion (liposomal clodronate [0.2 ml/20–25 g body weight i.p.]). Macrophage accumulation was assessed by immunohistochemistry. Tissue levels of SDF-1 (ELISA) and SDF-1 mRNA expression (real-time PCR) were measured. The cellular location of SDF-1 was assessed using immunohistochemical staining.Results
Immunofluorescence staining of renal tissue sections confirmed macrophage depletion by liposomal clodronate. SDF-1 production was elevated in response to I/R injury and was significantly increased upon macrophage depletion. SDF-1 positive cells initially appeared initially in the cortex, and subsequently diffused to the outer medulla after I/R injury.Conclusions
Our study demonstrates that SDF-1 is significantly upregulated during renal I/R. We hypothesize that SDF-1 upregulation may be an important macrophage effector mechanism during I/R injury. 相似文献100.
Chuanbo Fan Jinyu Wei Chenglu Yuan Xin Wang Chuanwu Jiang Changchun Zhou Ming Yang 《PloS one》2014,9(9)
As a heterogeneous kind of malignances, Non-Hodgkin lymphoma (NHL) is the most common hematologic cancer worldwide with the significantly increased morbidity in China. Accumulated evidences demonstrated that oncoprotein MDM4 plays a crucial role in the TP53 tumor suppressor signaling pathway. An rs4245739 A>C polymorphism locating in the MDM4 3′-untranslated region creates a miR-191 target site and results in allele-specific MDM4 expression. In this study, we examined the association between this polymorphism as well as the TP53 Arg72Pro (rs1042522 G>C) genetic variant and Non-Hodgkin Lymphoma (NHL) risk in a Chinese Han population. Genotypes were determined in 200 NHL cases and 400 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression. We found significantly increased NHL risk among carriers of the TP53 72Pro allele compared with those with the 72Arg allele (P = 0.002 for the Pro/Pro genotype). We also observed a significantly decreased NHL risks among carriers of the MDM4 rs4245739 C allele compared with those with the A allele in Chinese (P = 0.014 for the AC genotype). Stratified analyses revealed the associations between these SNPs and NHL risk are especially noteworthy in young or male individuals. Additionally, the associations are much pronounced in NHL patients with B-cell lymphomas or grade 3 or 4 disease. Our results indicate that the TP53 Arg72Pro and the MDM4 rs4245739 polymorphisms contribute to NHL susceptibility and support the hypothesis that genetic variants in the TP53 pathway genes can act as important modifiers of NHL risk. 相似文献