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11.
Cordyceps cicadae is a medicinal fungus used in treating night sweat, childhood convulsions, vision improvement and pain. This study was designed to evaluate the anti‐diabetic activity of the crude polysaccharide (SHF) from the mycelium and body portion of Ccicadae. Diabetes mellitus was induced in the rat with a single intravenous injection of alloxan monohydrate (150 mg/kg). In other to evaluate the anti‐diabetic effects of Ccicadae polysaccharide in alloxan‐induced diabetic rats, the crude polysaccharide (SHF at 100, 200 and 400 mg/kg body weight) and glibenclamide were administered orally to diabetic rats for 30 days. Blood glucose level, total cholesterol (TC), triglyceride (TG), low density lipoprotein (LDL), high density lipoprotein (HDL), alanine transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphate (ALP), creatinine (CREA), urea, malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH) were determined. SHF showed significant reduction in blood glucose in diabetic rats. Treatment of diabetic rats also resulted an improvement in body weights, increased HDL, SOD and GSH, as well as decreased TC, TG, LDL, MDA, urea, CREA, ALT, AST and ALP. These results suggested that Ccicadae polysaccharide displayed anti‐hyperglycemic, anti‐hyperlipidemic and antioxidant activities and could be a promising therapeutic source in managing diabetes mellitus and its associated complications.  相似文献   
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Background  

The Y-chromosomal diversity in the African buffalo (Syncerus caffer) population of Kruger National Park (KNP) is characterized by rainfall-driven haplotype frequency shifts between year cohorts. Stable Y-chromosomal polymorphism is difficult to reconcile with haplotype frequency variations without assuming frequency-dependent selection or specific interactions in the population dynamics of X- and Y-chromosomal genes, since otherwise the fittest haplotype would inevitably sweep to fixation. Stable Y-chromosomal polymorphism due one of these factors only seems possible when there are Y-chromosomal distorters of an equal sex ratio, which act by negatively affecting X-gametes, or Y-chromosomal suppressors of a female-biased sex ratio. These sex-ratio (SR) genes modify (suppress) gamete transmission in their own favour at a fitness cost, allowing for stable polymorphism.  相似文献   
14.
A total of 1388 goats from 31 farms distributed throughout Sardinia, Italy, were investigated in this study. The goat population of Sardinia accounts for a quarter of the entire goat population of Italy. In this work, data and information concerning each farming site were collected, a detailed clinical examination of the udder of lactating animals was carried out, and microbiological examination of milk was performed. Results were then subjected to statistical analysis in order to highlight possible correlations among all findings. Significant results were obtained by comparing clinical findings with bacteriological positivity of milk.Intra-mammary infections were detected in 22.7% of all goats examined. Staphylococcus spp., Streptococcus spp., and Mycoplasma spp. were detected in 73.5%, 9.7%, and 4.7% of positive milk cultures, respectively. Other bacterial genera showed a prevalence lower than 3%. Milk positivity to Staphylococcus aureus was significantly associated to presence in the udder of pustules, ulcers, nodules, and rubor (p < 0.05). Staphylococcus caprae was associated to manual vs mechanical milking, age, udder edema, and absence of mammary secretions (p < 0.05). Staphylococcus epidermidis was positively associated to age (p < 0.05). Streptococcus uberis was associated to mechanical milking, atrophic udder texture, and reactive mammary lymph nodes (p < 0.05). Several other factors showed statistically significant correlations. Taken together, the results presented in this work highlight the specificity, the usefulness, and the practical value of performing a clinical examination of the udder, and suggest its relevance as the most important diagnostic tool for complementing microbiological examination of milk.  相似文献   
15.
Hedysarum coronarium (sulla) is a legume native to the Mediterranean basin, known for its broad tolerance to various environmental stresses, and its ability to thrive without signs of chlorosis when growing in arid and alkaline soils up to pH 9.6. A unique but poorly known morphological feature of its root system is the production of “shovels”, modified lateral roots that acquire a curved and flattened shape. A combined structural and functional analysis was undertaken to define the nature and role of the shovel roots using various microscopy techniques, histochemical stains, STEM - energy dispersive X-ray microanalysis, infrared spectroscopy, and plant cultivation in different conditions. We found that sulla displays remarkable unique rhizosphere-buffering properties at both ends of the pH scale, and that shovels act as efficient calcium-absorbing organs that accumulate this cation intracellularly as insoluble crystalline salts. Such bioaccumulation results in a localized depletion of CaCO3 from the soil. As a consequence of this removal of the pivotal carbonate buffering system, the iron-solubilizing acidification activities of the roots can become effective. Further tests revealed that the factor triggering shovel development is exposure of roots to iron oxide. This signal, reporting at once both iron presence and alkalinity, assures the availability of iron nutrient reserves upon acidification of the local microenvironment surrounding the roots. These findings, besides casting light on a novel and unique botanical phenomenon, offer the potential to exploit sulla’s model and genes for the improvement of other crops to sustain productivity in a scenario of climate warming and increasing desertification.  相似文献   
16.
The estuary tides affect groundwater dynamics; these areas are susceptible to waterlogging and salinity issues. A study was conducted on two fields with a total area of 60 hectares under a center pivot irrigation system that works with solar energy and belong to a commercial farm located in Northern Sudan. To monitor soil salinity and calcium carbonate in the area and stop future degradation of soil resources, easy, non-intrusive, and practical procedures are required. The objective of this study was to use remote sensing-determined Sentinel-2 satellite imagery using various soil indices to develop prediction models for the estimation of soil electrical conductivity (EC) and soil calcium carbonate (CaCO3). Geo-referenced soil samples were collected from 72 locations and analyzed in the laboratory for soil EC and CaCO3. The electrical conductivity of the soil saturation paste extract was represented by average values in soil dataset samples from two fields collected from the topsoil layer (0 to 15 cm) characteristic of the local salinity gradient. The various soil indices, used in this study, were calculated from the Sentinel-2 satellite imagery. The prediction was determined using the root mean square error (RMSE) and cross validation was done using coefficient of determination. The results of regression analysis showed linear relationships with significant correlation between the EC analyzed in laboratory and the salinity index-2 “SI2” (Model-1: R2 = 0.59, p = 0.00019 and root mean square error (RMSE = 1.32%) and the bare soil index “BSI” (Model-2: R2 = 0.63, p = 0.00012 and RMSE = 6.42%). Model-1 demonstrated the best model for predicting soil EC, and validation R2 and RMSE values of 0.48% and 1.32%, respectively. The regression analysis results for soil CaCO3 determination showed linear relationships with data obtained in laboratory and the bare soil index “BSI” (Model- 3: R2 = 0. 45, p = 0.00021 and RMSE = 1.29%) and the bare soil index “BSI” & Normalized difference salinity index “NDSI” (Model-4: R2 = 0.53, p = 0.00015 and RMSE = 1.55%). The validation confirmed the Model-3 results for prediction of soil CaCO3 with R2 and RMSE values of 0.478% and 1.29%, respectively. Future soil monitoring programs might consider the use of remote sensing data for assessing soil salinity and CaCO3 using soil indices results generated from satellite image (i.e., Sentinel-2).  相似文献   
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18.

Background

Cigarette smoking is the major risk factor for COPD, leading to chronic airway inflammation. We hypothesized that cigarette smoke induces structural and functional changes of airway epithelial mitochondria, with important implications for lung inflammation and COPD pathogenesis.

Methods

We studied changes in mitochondrial morphology and in expression of markers for mitochondrial capacity, damage/biogenesis and fission/fusion in the human bronchial epithelial cell line BEAS-2B upon 6-months from ex-smoking COPD GOLD stage IV patients to age-matched smoking and never-smoking controls.

Results

We observed that long-term CSE exposure induces robust changes in mitochondrial structure, including fragmentation, branching and quantity of cristae. The majority of these changes were persistent upon CSE depletion. Furthermore, long-term CSE exposure significantly increased the expression of specific fission/fusion markers (Fis1, Mfn1, Mfn2, Drp1 and Opa1), oxidative phosphorylation (OXPHOS) proteins (Complex II, III and V), and oxidative stress (Mn-SOD) markers. These changes were accompanied by increased levels of the pro-inflammatory mediators IL-6, IL-8, and IL-1β. Importantly, COPD primary bronchial epithelial cells (PBECs) displayed similar changes in mitochondrial morphology as observed in long-term CSE-exposure BEAS-2B cells. Moreover, expression of specific OXPHOS proteins was higher in PBECs from COPD patients than control smokers, as was the expression of mitochondrial stress marker PINK1.

Conclusion

The observed mitochondrial changes in COPD epithelium are potentially the consequence of long-term exposure to cigarette smoke, leading to impaired mitochondrial function and may play a role in the pathogenesis of COPD.  相似文献   
19.

Objective

To assess the effects of subcutaneous (sc) interferon (IFN) -1a on cognition over 5 years in mildly disabled patients with relapsing–remitting multiple sclerosis (RRMS).

Methods

Patients aged 18–50 years with RRMS (Expanded Disability Status Scale score ≤4.0) who had completed the 3-year COGIMUS study underwent standardized magnetic resonance imaging, neurological examination, and neuropsychological testing at years 4 and 5. Predictors of cognitive impairment at year 5 were identified using multivariate analysis.

Results

Of 331 patients who completed the 3-year COGIMUS study, 265 participated in the 2-year extension study, 201 of whom (75.8%; sc IFN β-1a three times weekly: 44 µg, n = 108; 22 µg, n = 93) completed 5 years'' follow-up. The proportion of patients with cognitive impairment in the study population overall remained stable between baseline (18.0%) and year 5 (22.6%). The proportion of patients with cognitive impairment also remained stable in both treatment groups between baseline and year 5, and between year 3 and year 5. However, a significantly higher proportion of men than women had cognitive impairment at year 5 (26.5% vs 14.4%, p = 0.046). Treatment with the 22 versus 44 µg dose was predictive of cognitive impairment at year 5 (hazard ratio 0.68; 95% confidence interval 0.48–0.97).

Conclusions

This study suggests that sc IFN β-1a dose-dependently stabilizes or delays cognitive impairment over a 5-year period in most patients with mild RRMS. Women seem to be more protected against developing cognitive impairment, which may indicate greater response to therapy or the inherently better prognosis associated with female sex in MS.  相似文献   
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