全文获取类型
收费全文 | 907篇 |
免费 | 66篇 |
国内免费 | 3篇 |
专业分类
976篇 |
出版年
2024年 | 4篇 |
2023年 | 32篇 |
2022年 | 46篇 |
2021年 | 76篇 |
2020年 | 82篇 |
2019年 | 113篇 |
2018年 | 66篇 |
2017年 | 45篇 |
2016年 | 54篇 |
2015年 | 38篇 |
2014年 | 65篇 |
2013年 | 78篇 |
2012年 | 64篇 |
2011年 | 58篇 |
2010年 | 34篇 |
2009年 | 28篇 |
2008年 | 23篇 |
2007年 | 17篇 |
2006年 | 12篇 |
2005年 | 15篇 |
2004年 | 5篇 |
2003年 | 6篇 |
2002年 | 5篇 |
2000年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1985年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有976条查询结果,搜索用时 15 毫秒
101.
102.
103.
BACKGROUND: Placental site trophoblastic tumor (PSTT) is a rare and unique form of gestational trophoblastic disease (GTD). This tumor represents a neoplastic transformation of intermediate trophoblastic cells. We document a case of long term remission in a patient with metastatic PSTT. CASE PRESENTAION: A 27-year-old patient with metastatic PSTT was treated with combination therapy (chemotherapy and surgery). Patient is alive after 10 years without any evidence of recurrence. Literature on PSTT was searched using Medline and cross references, and pertinent articles were reviewed. CONCLUSION: With surgery and chemotherapy it is possible to achieve long-term remission in metastatic PSTT. Only a handful of previously reported cases with prolonged remission had been treated with the described combined chemotherapy and surgical approach. We suggest that this approach may be recommended for metastatic PSTT. 相似文献
104.
Fatemeh Ghaffarifar 《Experimental parasitology》2010,126(2):126-129
Cantharidin is a natural poisonous compound secreted by male blister beetles. The effect of different doses of cantharidin on Leishmania major (MRHO/IR/75/ER) were investigated both in vitro (promastigote and amastigote viability) and in experimentally-infected BALB/c mice (skin lesions) using ointment or soluble cantharidin. In this study, cantharidin with concentrations of 0.5, 1, 2, 5, 10, 20 and 50 μg/ml inhibited the growth of L. major promastigotes after 24 h and the resultant inhibition levels were 39.22%, 41.95%, 49.88%, 54.78%, 58.01%, 68.30% and 80.04%, respectively. After 72 h, the mean number of amastigotes per macrophage in the culture using 2 μg/ml of cantharidin, (the 50% inhibitory concentration dose (IC50)), was 1.2 while in the control group it was 2.7. In order to perform the inflammatory blister technique, 500 μg of cantharidin were solved in 25 μl of DMSO to show the formation of the blister which leads to treatment of cutaneous leishmaniasis. Using the blister technique, the small lesions (<5 mm) healed after one session. Two weeks of topical treatment with 0.1% cantharidin ointment was an effective method for treating cutaneous leishmaniasis in infected BALB/c mice. 相似文献
105.
Tahereh Taheri Ali-Hatef Salmanian Fatemeh Doustdari Sima Rafati 《Experimental parasitology》2010,126(2):135-145
Leishmania major (L. major) signal peptidase type I (SPase I) is an endopeptidase encoded by a single-copy gene. In all organisms, SPase I is responsible for removing the signal peptide from secretory pre-proteins and releasing mature proteins to cellular or extra-cellular space. In this study, the role of SPase I in L. major is investigated by gene deletion using homologous recombination (HR). The null mutant of SPase I was not possible to create, suggesting that SPase I is an essential gene for parasite survival.The obtained heterozygote mutant by disrupting one allele of SPase I in L. major showed significantly reduced level of infectivity in bone marrow-derived macrophages. In addition, the heterozygote mutants are unable to cause cutaneous lesion in susceptible BALB/c mice. This is the first report showing that SPase I may have an important role in Leishmania infectivity, e.g. in differentiation and survival of amastigotes. Apparently, the SPase I expression is not essential for in vitro growth of the parasite. 相似文献
106.
Fatemeh Rafieenia Seyed Omar Ebrahimi Ensieh sadat Emadi Forough Taheri Somayeh Reiisi 《Biotechnology progress》2023,39(6):e3387
Today, biologic prodrugs have led to targeting specific tumor markers and have increased specificity and selectivity in cancer therapy. Various studies have shown the role of ncRNAs in cancer pathology and tumorigenesis and have suggested that ncRNAs, especially miRNAs, are valuable molecules in understanding cancer biology and therapeutic processes. Most miRNAs-based research and treatment are limited to chemically synthesized miRNAs. Synthetic alterations in these miRNA mimics may affect their folding, safety profile, and even biological activity. However, despite synthetic miRNA mimics produced by automated systems, various carriers could be used to achieve efficient production of bioengineered miRNAs through economical microbial fermentation. These bioengineered miRNAs as biological prodrugs could provide a new approach for safe therapeutic methods and drug production. In this regard, bioengineered chimeric miRNAs could be selectively processed to mature miRNAs in different types of cancer cells by targeting the desired gene and regulating cancer progression. In this article, we aim to review bioengineered miRNAs and their use in cancer therapy, as well as offering advances in this area, including the use of chimeric tRNA/pre-miRNAs. 相似文献
107.
Namvaran F Rahimi-Moghaddam P Azarpira N Nikeghbalian S 《Molecular biology reports》2012,39(3):3219-3223
Adiponectin which possesses anti-inflammatory and insulin-sensitizing properties is elevated in blood circulation of liver
cirrhosis patients. The genetic variations in the adiponectin gene can affect the circulating adiponectin level and stimulation
of adiponectin receptor that may affect the activity of adiponectin. We investigated the effect of adiponectin single nucleotide
polymorphisms (SNP) 45 T/G and adiponectin receptor-2 gene SNP 795G/A in cirrhotic Iranian population. A total of 97 cirrhotic
patients and 128 healthy controls from Iranian population were genotyped for the adiponectin and adiponectin receptor 2 gene
(+45T>G and 795G/A) by polymerase chain reaction-restriction fragment length polymorphism. G frequency was 21.1% versus 12.89%
(P = 0.001) for SNP45, and G frequency was 75.8% versus 76.2% (P = 0.526) for SNP795G/A in the patients and control group, respectively. Based on our findings, the expression of the G allele
at SNP45 is higher in the patient group compared with healthy subjects, suggesting that it may affect liver injury through
changes in the plasma adiponectin level. 相似文献
108.
Fatemeh Sheikhi Mohammad Roayaei Ardakani Naeimeh Enayatizamir Susana Rodriguez-Couto 《Indian journal of microbiology》2012,52(4):701-707
Ligninolytic enzyme complexes are involved in lignin degradation. Among them laccases are outstanding because they use molecular oxygen as a co-substrate instead of hydrogen peroxide as used by peroxidases. Bacterial laccase of Bacillus genus was first reported in Claus and Filip (Microbiol Res 152:209–216, 1997), since then more bacterial laccases have been found. In this research, laccase-producing bacteria were screened from pulp and paper industry wastewater, bagass and sugarcane rhizosphere. Nutrient agar medium containing 0.5 mM of guaiacol was used. It was observed that the laccase-producing strains developed brown colour from which 16 strains of Bacillus were identified. One of the isolated strains was identified as Bacillus subtilis WPI based on the results of biochemical tests and 16S rDNA sequence analysis. This strain showed laccase-like activity towards the oxidizing substrates ABTS and guaiacol. In this study guaiacol was used as the substrate of laccase activity assay. For determination of laccase activity of this isolate guaiacol was used as a substrate of assay for the first time in this study. SDS-PAGE and Native-PAGE confirmed the presence of laccase. 相似文献
109.
110.
Mojtaba Sankian Fatemeh Vahedi Nazanin Pazouki Malihe Moghadam Farahzad Jabbari Azad Abdol-Reza Varasteh 《Reports of Biochemistry & Molecular Biology》2012,1(1):25-29