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31.
Epidemiological evidence suggests the protective effect of vitamin D against colorectal cancer (CRC) and the polymorphisms in vitamin D receptor (VDR) gene may influence the development of CRC. In this study the possible association of VDR FokI and BsmI gene polymorphisms with CRC risk was examined. A total of 904 subjects, including 452 cases with CRC and 452 controls were enrolled in this study. All 904 subjects were genotyped for VDR FokI and BsmI gene polymorphisms by PCR-RFLP method. We observed no significant difference in genotype and allele frequencies between the cases with CRC and controls for the both FokI and BsmI polymorphisms either before or after adjustment for confounding factors including age, BMI, sex, and smoking status. Furthermore, no evidence for effect modification of the association VDR gene FokI and BsmI variants and CRC by BMI, sex, or tumor site was observed. In addition, there was no significant difference in genotype and allele frequencies between the normal weight (BMI <25 kg/m2) cases with CRC and overweight/obese (BMI ≥25 kg/m2) cases with CRC for the two SNPs. Our results do not lend support to the hypothesis that VDR gene FokI and BsmI polymorphisms are associated with the risk of CRC. However, further studies are required to confirm this finding.  相似文献   
32.
Phytohormones, such as auxin and cytokinin, are known to be involved in the regulation of plant responses to salinity stress and counteract the adverse effect of stress conditions. This work investigated the effects of the exogenous spraying of indole-3-acetic acid (IAA) and kinetin (KIN) during the reproductive phase on grain yield by examining the 1000-grain weight and filled-grain percentage as well as the changes in starch, total soluble sugars, sucrose, glucose and fructose concentrations in the grains of two rice cultivars under salt stress. The results indicated that the applied IAA and KIN led to an increased grain yield, 1000-grain weight and filled-grain percentage for both rice cultivars under salt stress. The storage starch content in the grain of the salt-sensitive cultivar was more than that in the salt-tolerant cultivar under IAA application compared with KIN, whereas a decrease in the total soluble sugar content was observed with both IAA and KIN treatments, in comparison to the non-hormone treatment. Interestingly, this study showed that IAA led to a much higher increase in the sucrose content in grain, as compared to the KIN. Furthermore, this experiment suggests that glucose and fructose may play important roles during salt stress because there were clearly higher concentrations of these sugars in the grain of the stressed cultivars under IAA and KIN application: it appears that their accumulation was the earliest response detected during the grain-filling period in rice. Finally, this work indicated that an increase in the rice grain yield, 1000-grain weight and filled-grain percentage are associated with an increase in the contents of starch, sucrose, glucose and fructose in grain caused by the application of IAA and KIN.  相似文献   
33.
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   
34.
Cognitive dysfunction occurs in patients with diabetes mellitus. The objective of this study was to examine whether bilateral intrahippocampal CA1 (intra-CA1) injection of aminoguanidine (AG) can either affect the Bcl-2 family gene expression or reduce the diabetic imposing abnormalities of passive avoidance learning (PAL) and memory. Rats were divided into five groups: control (C), control treated with normal saline (CS), control treated with AG (S-AG), diabetics (D), and diabetics treated with AG (D-AG). Diabetes mellitus was induced by a single intraperitoneal injection of streptozotocin (STZ) (50 mg/kg). AG (30 μg/rat) or vehicle was administered intra-CA1 bilaterally at the onset of hyperglycemia. PAL was assessed 7 weeks later. Animals were killed, and hippocampus was dissected following the behavioral test. The expressions of Bax, Bcl-2, and Bcl-xl mRNAs were measured using semiquantitative RT-PCR technique. The result of passive avoidance task showed that AG significantly improved the cognitive performance in diabetic rats. Moreover, AG treatment decreased the levels of Bcl-2 and Bcl-xL expressions in diabetic group. The ratio of Bax/Bcl-2 and Bax/Bcl-xL decreased significantly in AG-treated diabetic animals. In conclusion, initial treatment with AG by intra-CA1 micro-injection improves the impaired passive avoidance task in STZ-induced diabetic rats which may be related to the decreased Bax/Bcl-2 and Bax/Bcl-xL ratios.  相似文献   
35.
36.

Background

There are several reports demonstrating the role of CD8 T cells against Leishmania species. Therefore peptide vaccine might represent an effective approach to control the infection. We developed a rational polytope-DNA construct encoding immunogenic HLA-A2 restricted peptides and validated the processing and presentation of encoded epitopes in a preclinical mouse model humanized for the MHC-class-I and II.

Methods and Findings

HLA-A*0201 restricted epitopes from LPG-3, LmSTI-1, CPB and CPC along with H-2Kd restricted peptides, were lined-up together as a polytope string in a DNA construct. Polytope string was rationally designed by harnessing advantages of ubiquitin, spacers and HLA-DR restricted Th1 epitope. Endotoxin free pcDNA plasmid expressing the polytope was inoculated into humanized HLA-DRB1*0101/HLA-A*0201 transgenic mice intramuscularly 4 days after Cardiotoxin priming followed by 2 boosters at one week interval. Mice were sacrificed 10 days after the last booster, and splenocytes were subjected to ex-vivo and in-vitro evaluation of specific IFN-γ production and in-vitro cytotoxicity against individual peptides by ELISpot and standard chromium-51(51Cr) release assay respectively. 4 H-2Kd and 5 HLA-A*0201 restricted peptides were able to induce specific CD8 T cell responses in BALB/C and HLA-A2/DR1 mice respectively. IFN-γ and cytolytic activity together discriminated LPG-3-P1 as dominant, LmSTI-1-P3 and LmSTI-1-P6 as subdominant with both cytolytic activity and IFN-γ production, LmSTI-1-P4 and LPG-3-P5 as subdominant with only IFN-γ production potential.

Conclusions

Here we described a new DNA-polytope construct for Leishmania vaccination encompassing immunogenic HLA-A2 restricted peptides. Immunogenicity evaluation in HLA-transgenic model confirmed CD8 T cell induction with expected affinities and avidities showing almost efficient processing and presentation of the peptides in relevant preclinical model. Further evaluation will determine the efficacy of this polytope construct protecting against infectious challenge of Leishmania. Fortunately HLA transgenic mice are promising preclinical models helping to speed up immunogenicity analysis in a human related mouse model.  相似文献   
37.
Hormozgan Province plays a vital role in fishery, petroleum, and industrial activities in southern Iran. However, no comprehensive studies on organic pollution have been performed. PCBs and PAHs were analyzed in surface sediments from areas receiving industrial (nine sites), river (one site), and urban (two sites) effluents. The sediment samples were collected in March and September 2010 (in dry and wet seasons) at the highest tidal time. The overall pollution level of PCBs ranged from 2.5 ± 0.8 to 462.0 ± 206.7 ng/g dry weight. CB153 congener dominated in most of the sediment samples. Congener profiles of PCBs showed close similarity with formulations of commercial products such as Aroclor 1260 and 1254 g. A wide range of 55.3 to 1231.6 ng/g dry weight was detected for ∑PAHs. Results of PCA and PCA-MLR tests confirmed both petrogenic and pyrogenic origins for PAH pollution. The higher means of ∑PAHs and ∑PCBs in industrial and urban wastewaters were found near the shore, evidencing the role of these wastewaters in the PAH and PCB contamination in Hormozgan sediment. The concentrations of PAHs and PCBs in detected hotspots exceed the U.S. NOAA sediment quality guidelines.  相似文献   
38.
Treatment of Cutaneous leishmaniasis (CL) is based on using antimoniate derivatives; patients’ compliance for systemic injections is low due to the pain and systemic complications. In this randomized open trial, the efficacy of intra-lesional (IL) injections of meglumine antimoniate (MA) once a week vs. twice a week in the treatment of Anthrpoponothic CL caused by L. tropica was studied. Eligible volunteer patients were selected according to inclusion/exclusion criteria. The included patients were randomly allocated to receive IL-MA injections once a week or twice a week. The primary outcome was set as complete healing of the lesion(s), and defined as complete re-epithelialization and absence of induration in the lesions. A total of 180 parasitologicaly proven CL patients caused by L. tropica were recruited, 90 patients were treated with weekly IL-MA and 90 patients received IL-MA twice a week. The complete cure was 87.9% vs. 89.2% in the group received weekly and twice a week IL-MA injections, respectively (P = 0.808). Patients’ compliance was acceptable and side effects were limited to a few local allergic reactions to MA. Median time to healing was significantly shorter in patients who received IL-MA twice a week (median ± SE) 37±3.8, (CI: 29.6–44.4) days compared to whom received IL-MA once a week 60±2.3, (CI: 55.6–64.5) days (P< 0.001), however the number of injections was higher in group who received IL-MA twice a week (12 vs. 9 injections). In conclusion, the rate of cure in the group of CL patients with IL-MA twice a week was not significantly different from the group who received IL-MA once a week shorten, but the duration of healing was shorter in the group who received IL-MA twice a week while the group received more injections so is recommended to use IL-MA once a week due to the fact the compliance is acceptable with limited side effects.Clinical Trial Registration: IRCT20081130001475N13; https://en.irct.ir/.  相似文献   
39.
40.
Oil presence in soil, as a stressor, reduces phytoremediation efficiency through an increase in the plant stress ethylene. Bacterial 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, as a plant stress ethylene reducer, was employed to increase oil phytoremediation efficiency. For this purpose, the ability of ACC deaminase-producing Pseudomonas strains to grow in oil-polluted culture media and withstand various concentrations of oil and also their ability to reduce plant stress ethylene and enhance some growth characteristics of maize and finally their effects on increasing phytoremediation efficiency of poly aromatic hydrocarbons (PAHs) in soil were investigated. Based on the results, of tested strains just P9 and P12 were able to perform oil degradation. Increasing oil concentration from 0 to 10% augmented these two strains population, 15.7% and 12.9%, respectively. The maximum increase in maize growth was observed in presence of P12 strain. Results of high-performance liquid chromatography (HPLC) revealed that PAHs phytoremediation efficiency was higher for inoculated seeds than uninoculated. The highest plant growth and PAHs removal percentage (74.9%) from oil-polluted soil was observed in maize inoculated with P12. These results indicate the significance of ACC deaminase producing bacteria in alleviation of plant stress ethylene in oil-polluted soils and increasing phytoremediation efficiency of such soils.  相似文献   
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