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1.
Background: The protein of Niemann-pick type C1 (NPC1) gene promotes the egress of cholesterol from late endosomes and lysosomes to other cellular compartments and contributes to a process known as reverse cholesterol transport. This study aimed to examine whether promoter methylation of NPC1 is associated with risk of cardiovascular disease (CVD). Methods: Fifty CVD patients and 50 healthy subjects as the control group were recruited in this study. Promoter methylation of NPC1 gene was defined using a nested-methylation specific polymerase chain reaction method. Statistical analyses were done using the chi-square, t-test or ANOVA tests. Results: Our study showed that the frequency of semi-methylated promoter (methylated/unmethylated status) was significantly higher in CVD patients than that in controls (OR = 6.521, 95% CI = 2.211-19.215, P = 0.008). However, a completely methylated promoter (methylated/methylated status) was not detected in any subjects in either of the two groups tested. Additionally, the analysis of clinical data according to the methylation status of NPC1 gene demonstrated that serum levels of total cholesterol, total triglycerides, high low-density lipoprotein cholesterol (LDL-C) and low high-density lipoprotein cholesterol (HDL-C) are influenced by NPC1 methylation, so that subjects with a completely unmethylated promoter (Unmethylated/unmethylated status) held lower levels of total triglycerides, total cholesterol, LDL-C and higher levels of HDL-C. Conclusion: Our findings propose that the NPC1 promoter methylation is a probable mechanism that can result in reduced/impaired NPC1 expression/activity and may thus contribute to progression of CVD. Key Words: Niemann-pick type C1 (NPC1), Promoter methylation, cardiovascular disease  相似文献   
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The main purpose of the present investigation was to develop a pollution index for agricultural soils. For this purpose, 58 soil samples were collected from agricultural lands in Hamedan Province (Iran). The elemental contents of As, Cd and Co in soil samples and agricultural crops were measured by atomic absorption spectroscopy. The spatial distribution of studied metals was prepared by Kriging method. It is concluded that agricultural activities have led to the higher concentrations of Co, Cd and As. Results of the chemical partitioning studies revealed that a considerable portions of As, Cd and Co in agricultural soils are derived from anthropogenic sources. We believe that pollution index should show values that are in accordance with chemical partitioning data. The newly developed pollution index showed slightly higher values when compared with the previously published indices such as geochemical index (Igeo) and pollution index (Ipoll). The health risk index in the area of study was found to be lower than many other reported ones. Among the studied elements, Co has the highest transfer factor of 17.95 that could be attributed to its lower retention rate.  相似文献   
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Background: Brain hypoxia-ischemia is a human neonatal injury that is considered a candidate for stem cell therapy. Methods: The possible therapeutic potential of human umbilical cord blood (HUCB) stem cells was evaluated in 14-day-old rats subjected to the right common carotid occlusion, a model of neonatal brain hypoxia-ischemia. Seven days after hypoxia-ischemia, rats received either saline solution or 4 × 105 HUCB cells i.v. Rats in control group did not receive any injection. After two weeks, rats were assessed using two motor tests. Subsequently, rats were scarified for histological and immunohistochemical analyses. Results: Our immunohistochemical findings demonstrated selective migration of the injected HUCB cells to the ischemic area as well as reduction in infarct volume. Seven days after surgery, we found significant recovery in the behavioral performance in the test group (12.7 +/- 0.3) compared to the sham group (10.0 +/-0.05), a trend which continued to day 14 (15.3 ± 0.3 vs. 11.9 ± 0.5, P<0.05). Postural and motor asymmetries at days 7 and 14 in the test group showed a significant decrease in the percentage of right turns in comparison to the sham group (75% and 59% vs. 97% and 96%, P<0.05). Conclusion: The results show the potential of HUCB stem cells in reduction of neurologic deficits associated with neonatal hypoxia-ischemia. Key Words: Hypoxia-Ischemia, Nerve cell, Umbilical Cord Blood  相似文献   
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Background:

Reduced susceptibility of Clostridium difficile to antibiotics is problematic in clinical settings. There is new evidence indicating the cotransfer of toxin-encoding genes and conjugative transposons encoding resistance to antibiotics among different C. difficile strains. To analyze this association, in the current study, we evaluated the frequency of toxigenic C. difficile among the strains with different multidrug-resistant (MDR) profiles in Iran.

Methods:

Antimicrobial susceptibility patterns and minimal inhibitory concentrations (MIC) of the isolates were determined against metronidazole, imipenem, ceftazidime, amikacin, and ciprofloxacin by agar dilution method. The association of the resistance profiles and toxigenicity of the strains were studied by PCR targeting tcdA and tcdB genes.

Results:

Among 86 characterized strains, the highest and lowest resistance rates were related to ciprofloxacin (97%) and metronidazole (5%), respectively. The frequency of resistance to other antibiotics was as follow: imipenem (48%), ceftazidime (76%), and amikacin (76.5%). Among the resistant strains, double drug resistance and MDR phenotypes were detected in the frequencies of 10.4% and 66.2%, respectively. All of the metronidazole-resistant strains belonged to tcdA +/tcdB + genotype with triple or quintuple drug resistance phenotypes. MIC50 and MIC90 for this antibiotic was equally ≤ 8 μg/ml.

Conclusion:

These results proposed the association of tcdA +/tcdB + genotype of C. difficile and the emergence of resistance strains to broad-spectrum antibiotics and metronidazole. Key Words: Multidrug resistance, Clostridium difficile, Metronidazole  相似文献   
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The use of recombinant gonadotropin-releasing hormone (rGnRH) has very rarely been tested in fish to promote spawning. This study evaluated the impact of recombinant chicken gonadotropin-releasing hormone (rcGnRH) with metoclopramide on the release of sex steroids and final maturation induction in goldfish (Carassius auratus) broodstock. For this purpose, goldfish broodstock was divided into four groups and treated with 0.9% NaCl with 20 mg/kg metoclopramide (Met) (C); 10 μg/kg body weight (BW) rcGnRH with 20 mg/kg metoclopramide (rcGn10); 15 μg/kg BW rcGnRH with 20 mg/kg metoclopramide (rcGn15); and 20 μg/kg BW rcGnRH with 20 mg/kg metoclopramide (rcGn20). The capability of the rcGnRH for eliciting biological response was tested in vivo by evaluating the changes of 17β estradiol (E2), testosterone (T), and 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) and the induced spawning. Blood samples were obtained at 0 h, 12 h, and 24 h after injection. The rcGn10, rcGn15, and rcGn20 treatments induced lower E2 concentration, especially 24 h post-injection. T levels were significantly higher in rcGn10, rcGn15, and rcGn20 treatments 12 h post-injection than at 0 h and then decreased at 24 h post-injection. Furthermore, the rcGnRH tested significantly enhanced DHP secretion in rcGn10, rcGn15, and rcGn20 treatments 12 h post-injection before a decline at 24 h post-injection. No significant difference between the sampling times was found in the C treatment for the 3 sex steroids tested. The results also displayed that rcGnRH at 10–20 µg/kg of body weight can trigger spawning with the highest speed and efficiency of spawning at 20 µg/kg. The obtained results represent a possible strategy for enhancing the artificial reproduction and ovulation of broodstock fish by rGnRH and further support the use of recombinant hormones to promote reproduction in aquaculture.

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7.
This experiment was carried out to investigate the potential probiotics properties of Bacillus subtilis in protecting of juvenile freshwater prawn, Macrobrachium rosenbergii against Aeromonas hydrophila infection. A B. subtilis bacterium isolated from gut of juvenile prawns was added to the prawns feed at 108 cells g?1 feed. There were significant differences (P < 0.05) between B. subtilis-treated and control groups in growth and survival enhancement of juvenile prawns after 60 days of feeding trial. Sixty days after B. subtilis feeding trial, the prawns were challenged by bath exposure to A. hydrophila (107 cells mL?1) for 28 days. Four weeks after challenge, there was significant difference in the survival of prawns between B. subtilis-treated groups (88.33 %) and control groups (20.81 %; P < 0.05). In addition, the control groups had an unhealthy external appearance, while the treated groups, appeared healthy and normal. From this, it was concluded that the selected B. subtilis may be a promising probiotics for protection of prawns from A. hydrophila infection.  相似文献   
8.
The accuracy of the knowledge of mass transfer parameters(effective moisture diffusivity,mass transfer Biot number and mass transfer coefficient) in the case of frying food,is essential and important for designing,modeling and process optimization.This study is undertaken to develop an approach for determining mass transfer parameters during frying of spherical rice cracker in sunflower oil at 150,170 and 190 ℃.These parameters were evaluated from the plots of dimensionless concentration ratios against time of frying.Effective moisture diffusivity,mass transfer Biot number and mass transfer coefficient ranged between 1.24×10-8 to 2.36×10-8 m2/s,1.96 to 2.34 and 5.51×10-6 to 9.70×10-6 m/s,respectively.Effective moisture diffusivity and mass transfer coefficient were found to increase with an increasing frying temperature,whereas mass transfer Biot number decreased.An Arrhenius-type relationship was found between effective diffusivity coefficient and frying temperature.  相似文献   
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Drought is a worldwide concern and designation of drought stress adaptive mechanisms is one of the main directions in plant physiology and crop breeding. Genotypes diversity can be used to identify effective unexploited genes and pathways. In order to that, the effect of varying terminal drought intensity treatments on physiological and biochemical traits was evaluated in ILC3279, ICCV2 and FLIP9855 C chickpea lines. Well-watered, intermediate and severe drought treatments were applied from flowering till maturity. Photosynthetic efficiency, membrane stability, soluble sugar and proline content, leaf protein profile, and antioxidant enzyme activities were compared on 1st, 3rd, and 5th week after applying stress. Based on the results, it was found that the susceptibility of photosynthetic machinery of ILC3279 was more than others. Tolerant genotypes responded to drought differently; an increase and a decrease in catalase activity have been observed in ICCV2 and FLIP9855 C, respectively. The prominent role of soluble sugars was observed in ICCV2. Expressions of polypeptides 27 and 45 kDa in tolerant lines refer to their possible role in drought stress adaptation. Generally, in spite of significant variability in chickpea lines to cope with drought, lower ascorbate peroxidase activity, higher peroxidase activity, and higher Fv/Fm ratio can be tested as markers of chickpea drought tolerant.  相似文献   
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