全文获取类型
收费全文 | 506篇 |
免费 | 39篇 |
出版年
2023年 | 8篇 |
2022年 | 19篇 |
2021年 | 32篇 |
2020年 | 28篇 |
2019年 | 52篇 |
2018年 | 33篇 |
2017年 | 23篇 |
2016年 | 36篇 |
2015年 | 34篇 |
2014年 | 36篇 |
2013年 | 49篇 |
2012年 | 41篇 |
2011年 | 36篇 |
2010年 | 24篇 |
2009年 | 21篇 |
2008年 | 8篇 |
2007年 | 15篇 |
2006年 | 14篇 |
2005年 | 8篇 |
2004年 | 12篇 |
2003年 | 5篇 |
2002年 | 3篇 |
2001年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1991年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有545条查询结果,搜索用时 31 毫秒
101.
Mohammad Reza Zafarghandi Hassan Ravari Nasser Aghdami Mehrnaz Namiri Kasra Moazzami Ehsan Taghiabadi Abdorreza Fazel Behshad Pournasr Ali Farrokhi Ramezan Ali Sharifian Javad Salimi Majid Moini Hossein Baharvand 《Cytotherapy》2010,12(6):783-791
Background aimsThe aim was to investigate the therapeutic effect of granulocyte–colony-stimulating factor (G-CSF) administration following implantation of autologous bone marrow mononuclear cells (BM MNC) for patients with lower limb ischemia.MethodsThe design was a randomized controlled trial. Fifteen patients with severe chronic limb ischemia were treated with autologous BM MNC [without G-CSF (MNC–G-CSF) or combined with G-CSF administration for 5 days following transplantation (MNC+G-CSF)].ResultsAll clinical parameters, including ankle brachial index, visual analog scale and pain-free walking distance, showed a mean improvement from baseline, which was measured at 4 and 24 weeks after transplantation in both groups. However, in three (20%) patients, the clinical course did not improve and limb salvage was not achieved. No significant difference was observed among the patients treated in the MNC–G-CSF and MNC+G-CSF groups. No severe adverse reactions were reported during the study period. No relationship was observed between both the numbers of viable MNC or CD34+ cells and the clinical outcome.ConclusionsAutologous transplantation of BM MNC into ischemic lower limbs is safe, feasible and efficient for patients with severe peripheral artery disease. However, the administration of G-CSF following cell transplantation does not improve the effect of BM MNC implantation and therefore would not have any beneficial value in clinical applications of such cases. 相似文献
102.
103.
104.
Focal adhesions are critical to a number of cellular processes that involve mechanotransduction and mechanical interaction with the cellular environment. The growth and strengthening of these focal adhesions is dependent on the interaction between talin and vinculin. This study investigates said interaction and how vinculin activation influences it. Using molecular dynamics, the interaction between talin's vinculin binding site (VBS) and vinculin's domain 1 (D1) is simulated both before and after vinculin activation. The simulations of VBS binding to vinculin before activation suggest the proximity of the vinculin tail to D1 prevents helical movement in D1 and thus prevents binding of VBS. In contrast, interaction of VBS with activated vinculin shows the possibility of complete VBS insertion into D1. In the simulations of both activated and autoinhibited vinculin where VBS fails to fully bind, VBS demonstrates significant hydrophobic interaction with surface residues in D1. These interactions link VBS to D1 even without its proper insertion into the hydrophobic core. Together these simulations suggest VBS binds to vinculin with the following mechanism: 1), VBS links to D1 via surface hydrophobic interactions; 2), vinculin undergoes activation and D1 is moved away from the vinculin tail; 3), helices in D1 undergo conformational change to allow VBS binding; and 4), VBS inserts itself into the hydrophobic core of D1. 相似文献
105.
Tavakkoly-Bazzaz J Amiri P Tajmir-Riahi M Javidi D Khojasteh-Fard M Taheri Z Tabrizi A Keramatipour M Amoli MM 《Gene》2011,487(1):103-106
Objective
Increased RANTES expression has been described to have a role in atherosclerosis plaque formation. Functional polymorphisms within RANTES promoter region have shown association with increased risk of coronary atherosclerosis (CAD). The aim of this study was to examine the RANTES mRNA expression in patients with CAD compared to patients without CAD and its association with RANTES − 403 G/A polymorphism in an Iranian population.Methods
The study was performed on 319 patients who underwent coronary artery angiography and patients with > 50% stenosis in vessels considered as case groups (CAD+) N = 191 and normal vessels group as control (CAD−) N = 128. In each group 20 patients were examined for RANTES mRNA expression.RANTES mRNA expression was examined using quantitative real-time PCR. Genotyping of − 403 polymorphism was performed using PCR-RFLP technique.Results
We found that RANTES mRNA expression was increased to 1.37 fold in CAD patients compared to the controls but the difference was not statistically significant. Also comparing the RANTES mRNA expression in patients with different RANTES − 403 G/A polymorphism showed that in patients carrying AA genotype RANTES mRNA expression was increased to 1.74 fold compared to patients carrying GG genotype and to 1.51 fold compared to patients carrying GA genotype. No significant difference for allele and genotype frequencies of RANTES − 403 polymorphism was found between cases and controls.Conclusion
More studies on larger number of samples are required to further evaluate role of RANTES in pathogenesis of CAD. 相似文献106.
Sherafat MA Javan M Mozafari S Mirnajafi-Zadeh J Motamedi F 《Neurochemical research》2011,36(10):1887-1895
Multiple sclerosis (MS) is a demyelinating disease that affects the central nervous system. MS is the most common neurological
disorder in young adults with a greater incidence among females. Male gonadal hormones have a protective effect on neural
system development and myelin maturation. In this study, we investigate the effect of castration on lysolecithin-induced demyelination
and remyelination processes using visual evoked potentials, in addition to measuring the expressions of Olig2, MBP, Nogo-A
and GFAP mRNAs as oligodendrocyte or astrocyte markers; and histological assessments by myelin-specific staining. We observed
more expanded demyelination with delayed repair process in castrated rats. Expression levels of the aforementioned marker
genes confirmed histological and electrophysiological observations. Our results showed a pivotal role for endogenous male
hormones in the context of demyelinating insults. It may also account for the different prognosis of MS between male and female
genders and provide new insights for therapeutic treatments. 相似文献
107.
Zomorodian K Rahimi MJ Safaei A Bazargani A Motamadi M Kharazi M Mostaghni S Pakshir K Ghaedi H Afsarian MH 《Journal of microbiological methods》2011,85(3):233-234
The aim of the study was to assess the reliability of human blood agar media (HuBA) in identifying Streptococcus pyogenes by hemolysis analysis. We analyze several factors that might affect the accuracy of HuBA media for microbial analysis, including incubation time, blood group, Rh factor and presence of antistreptolysin-o. 相似文献
108.
Traditionally estimating pesticide effects by measuring only lethal effect may underestimate the total negative effect on beneficial arthropods and sublethal effects should be assessed to estimate the total effect of their applications. In this study, sublethal effect of the acaricide abamectin (Vermectin® 1.8% EC, Giah, Iran) on the predatory mite Phytoseius plumifer (Canestrini &; Fanzago) (Acari: Phytoseiidae) fed on Tetranychus urticae Koch was assessed in laboratory conditions. The adult predators were exposed to the residues of the acaricide on fig leaves and the LC50 value was determined based on a concentration–response analysis. The results showed that sublethal concentrations (LC10, LC20 and LC30) of abamectin severely affected the fecundity and longevity of the treated females of P. plumifer. Furthermore, reproductive and life table parameters of the subsequent generation were affected. The results indicated that adverse effects of abamectin on population growth of P. plumifer were significant, so the results from this study can be used to develop approximate guidelines for the use of abamectin in order to minimize their impact on P. plumifer and related natural enemies. 相似文献
109.
Alipour M Gholami MR Jafari Anarkooli I Sohrabi D Tajki J Pourheidar M 《Cellular and molecular neurobiology》2011,31(5):765-773
The present work was designed to investigate the potential protective effects of post-ischemic treatment with aminoguanidine
(AG) on sciatic nerve ischemia/reperfusion (I/R) injury in rat. Seventy-two rats were divided into 12 groups (n = 6). We used ischemia model in these groups by occluding the right common iliac and femoral arteries for 3 h with a silk
suture 6-0 using slipknot technique. Treatment groups (2, 4, 6, 8, 10, and 12) received 150 mg/kg AG intraperitoneally 24 h
after induction of ischemia. After certain time intervals of reperfusion (2, 4, 7, 14, and 28 days), the function of the hind
limb was assessed using behavioral scores based on gait, racing reflex, toe spread, pinch sensitivity, paw position, and grasp.
After euthanasia, sciatic nerves were removed at the end of reperfusion times and sections were cut at 5 μm, then were stained
for light microscopy studies and graded for ischemic fiber degeneration (IFD), edema, and apoptosis. Maximal behavioral deficit
occurred at 7 days of reperfusion. The comparison of behavioral score pertaining to the control and AG groups revealed significant
differences and showed also a better time course in recovery (P < 0.05). Other than 3 and 4 groups, the amount of edema in AG treatment groups showed significant differences compared with
control groups (P < 0.05). IFD was also significantly decreased in the AG treatment groups than controls. Most importantly, I/R-induced apoptosis
were improved significantly on the 4th, 7th, and 14th days of reperfusion in AG-treated groups compared to controls. In conclusion, our findings suggest that post-ischemic
administration of AG exhibits protective effect against sciatic nerve I/R injury. 相似文献
110.
Farnia P Mohammadi F Mirsaedi M Zia Zarifi A Tabatabee J Bahadori M Akbar Velayati A Reza Masjedi M 《Microbes and infection / Institut Pasteur》2004,6(11):972-976
The viability of Mycobacterium tuberculosis (MTB) in serial sputum specimens from persistently smear positive patients was evaluated. The assay was based on oxidation-reduction of Alamar Blue and Malachite Green dyes that change their color in response to MTB growth. A total of 280 sputum specimens from 40 persistently smear positive TB patients and 40 sputa from non-tuberculosis patients were digested, decontaminated and examined microscopically. To check the MTB viability, the sediments from decontaminated samples were inoculated into three culture media: Lowenstein-Jensen (LJ) slants, Alamar Blue and Malachite Green culture tubes. We found that out of 280 smear positive specimens, the LJ culture was positive in 124 (44%). The numbers of correctly identified S+/C+ cases by Alamar Blue and Malachite Green were 118 (95%) and 116 (93%), respectively. The mean time required for reporting the positive signal in Alamar Blue culture tubes was 9 versus 11 days by Malachite Green culture tubes. In the standard LJ culture media the average detection time was 27 days (P < 0.05). The sensitivity of LJ was 99%, Alamar Blue 95% and Malachite Green 93%. The specificity was 100%, 92% and 93%, respectively. The oxidation-reduction method is rapid, sensitive and inexpensive in monitoring the treatment response of patients with pulmonary TB. Thus, using this method can be of paramount importance, particularly in resource-constrained areas. 相似文献