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101.
Treatment of oil sands process-affected water (OSPW) using biodegradation has the potential to be an environmentally sound approach for tailings water reclamation. This process is both economical and efficient, however, the recalcitrance of some OSPW constituents, such as naphthenic acids (NAs), require the pre-treatment of raw OSPW to improve its biodegradability. This study evaluated the treatment of OSPW using ozonation followed by fluidized bed biofilm reactor (FBBR) using granular activated carbon (GAC). Different organic and hydraulic loading rates were applied to investigate the performance of the bioreactor over 120 days. It was shown that ozonation improved the adsorption capacity of GAC for OSPW and improved biodegradation by reducing NAs cyclicity. Bioreactor treatment efficiencies were dependent on the organic loading rate (OLR), and to a lesser degree, the hydraulic loading rate (HLR). The combined ozonation, GAC adsorption, and biodegradation process removed 62 % of chemical oxygen demand (COD), 88 % of acid-extractable fraction (AEF) and 99.9 % of NAs under optimized operational conditions. Compared with a planktonic bacterial community in raw and ozonated OSPW, more diverse microbial communities were found in biofilms colonized on the surface of GAC after 120 days, with various carbon degraders found in the bioreactor including Burkholderia multivorans, Polaromonas jejuensis and Roseomonas sp.  相似文献   
102.
A high degree of endemism has been recorded for several plant groups collectively in Saint Katherine Protectorate (SKP) in the Sinai Peninsula. Nine endangered endemic plant species in SKP were selected to test the variable abilities of three different DNA barcodes; Riboluse-1,5- Biphosphate Carboxylase/Oxygenase Large subunit (rbcL), Internal Transcribed Spacer (ITS), and the two regions of the plastid gene (ycf1) as well as Start Codon Targeted (SCoT) Polymorphism to find the phylogenetic relationships among them. The three barcodes were generally more capable of finding the genetic relationships among the plant species under study, new barcodes were introduced to the National Centre for Biotechnology Information (NCBI) for the first time through our work. The barcode sequences were efficient in finding the genetic relationships between the nine species. However, SCoT polymorphism could only cluster plant species belonging to the same genus together in one group, but it could not cluster plant species belonging to the same families except for some primers solely. RbcL was the most easily amplified and identified barcode in eight out of the nine species at the species level and the ninth barcode to the genus level. ITS identified all the species to the genus level. Finally, ycf1 identified six out of the eight species, but it could not identify two of the eight species to the genus level.  相似文献   
103.
104.
The present study was undertaken to investigate the utility of cystatin C (CysC) as an early biomarker of cadmium (Cd)-induced renal injury. The study was carried out on 50 adult male individuals divided into five groups of 10 individuals as follows: control, welders, smoker welders, diabetic welders, and smoker diabetic welders. The results indicated that plasma levels of CysC, creatinine, urea, and uric acid were significantly higher in welders compared to control individuals. In addition, the levels of whole blood Cd, lipid peroxidation, and protein oxidation products as well as erythrocyte osmotic fragility were significantly higher in welders compared to control individuals. In contrast, the levels of plasma albumin and whole blood glutathione were significantly decreased in welders compared to control individuals. The alterations of the measured parameters were enhanced in the presence of smoking and hyperglycemia besides exposure to welding fumes. These results suggest that CysC can be used as a sensitive biomarker of the early stages of Cd-induced renal injury.  相似文献   
105.

Introduction

Evidence from a number of open-label, uncontrolled studies has suggested that rituximab may benefit patients with autoimmune diseases who are refractory to standard-of-care. The objective of this study was to evaluate the safety and clinical outcomes of rituximab in several standard-of-care-refractory autoimmune diseases (within rheumatology, nephrology, dermatology and neurology) other than rheumatoid arthritis or non-Hodgkin''s lymphoma in a real-life clinical setting.

Methods

Patients who received rituximab having shown an inadequate response to standard-of-care had their safety and clinical outcomes data retrospectively analysed as part of the German Registry of Autoimmune Diseases. The main outcome measures were safety and clinical response, as judged at the discretion of the investigators.

Results

A total of 370 patients (299 patient-years) with various autoimmune diseases (23.0% with systemic lupus erythematosus, 15.7% antineutrophil cytoplasmic antibody-associated granulomatous vasculitides, 15.1% multiple sclerosis and 10.0% pemphigus) from 42 centres received a mean dose of 2,440 mg of rituximab over a median (range) of 194 (180 to 1,407) days. The overall rate of serious infections was 5.3 per 100 patient-years during rituximab therapy. Opportunistic infections were infrequent across the whole study population, and mostly occurred in patients with systemic lupus erythematosus. There were 11 deaths (3.0% of patients) after rituximab treatment (mean 11.6 months after first infusion, range 0.8 to 31.3 months), with most of the deaths caused by infections. Overall (n = 293), 13.3% of patients showed no response, 45.1% showed a partial response and 41.6% showed a complete response. Responses were also reflected by reduced use of glucocorticoids and various immunosuppressives during rituximab therapy and follow-up compared with before rituximab. Rituximab generally had a positive effect on patient well-being (physician''s visual analogue scale; mean improvement from baseline of 12.1 mm).

Conclusions

Data from this registry indicate that rituximab is a commonly employed, well-tolerated therapy with potential beneficial effects in standard of care-refractory autoimmune diseases, and support the results from other open-label, uncontrolled studies.  相似文献   
106.

Background

Many studies in high-income countries have investigated gender differences in the care and outcomes of patients hospitalized with acute myocardial infarction (AMI). However, little evidence exists on gender differences among patients with AMI in lower-middle-income countries, where the proportion deaths stemming from cardiovascular disease is projected to increase dramatically. This study examines gender differences in patients in the lower-middle-income country of Egypt to determine if female patients with AMI have a different presentation, management, or outcome compared with men.

Methods and Findings

Using registry data collected over 18 months from 5 Egyptian hospitals, we considered 1204 patients (253 females, 951 males) with a confirmed diagnosis of AMI. We examined gender differences in initial presentation, clinical management, and in-hospital outcomes using t-tests and χ2 tests. Additionally, we explored gender differences in in-hospital death using multivariate logistic regression to adjust for age and other differences in initial presentation.We found that women were older than men, had higher BMI, and were more likely to have hypertension, diabetes mellitus, dyslipidemia, heart failure, and atrial fibrillation. Women were less likely to receive aspirin upon admission (p<0.01) or aspirin or statins at discharge (p = 0.001 and p<0.05, respectively), although the magnitude of these differences was small. While unadjusted in-hospital mortality was significantly higher for women (OR: 2.10; 95% CI: 1.54 to 2.87), this difference did not persist in the fully adjusted model (OR: 1.18; 95% CI: 0.55 to 2.55).

Conclusions

We found that female patients had a different profile than men at the time of presentation. Clinical management of men and women with AMI was similar, though there are small but significant differences in some areas. These gender differences did not translate into differences in in-hospital outcome, but highlight differences in quality of care and represent important opportunities for improvement.  相似文献   
107.
Diabetic peripheral neuropathy (DPN) is one of the most common diabetic chronic complications. The pathogenesis of DPN is complex and involves an intertwined array of mechanisms. The purposes of this study were to evaluate the association of oxidative stress and vascular risk factors with the prevalence of DPN and to determine the role of these biochemical parameters in the prognosis of DPN. One hundred patients with type 2 diabetes mellitus and 40 clinically healthy individuals were evaluated. The patients were divided into two groups. Group 1 included 40 diabetic patients without peripheral neuropathy, and group 2 consisted of 60 patients with DPN. Erythrocytes glutathione (GSH) level, plasma malondialdehyde (MDA), nitrite/nitrate (NOx) and homocysteine (Hcy) levels as well as serum ceruloplasmin (Cp), total antioxidants (TAO), endothelin-1 (ET-1) levels and γ-glutamyl transferase (GGT) activity were estimated. A significant decrease of erythrocyte GSH was observed in groups 1 and 2 relative to the controls. An increase in glycosylated haemoglobin (HbA1c), MDA, NOx, GGT, Cp, TAO, Hcy and ET-1 was noted in patients with DPN. In conclusion, oxidative stress biomarkers and vascular risk factors could be important in the pathogenesis of DPN. The measurement of serum GGT and Hcy in addition to HbA1c and disease duration could facilitate the early detection of neuropathy in diabetic patients.  相似文献   
108.
109.
Whey protein concentrates (WPCs) enhance innate mucosal immunity during early life and have a protective role in some immune disorders. To further elucidate the potential benefits of this protein, the present study investigated the effect of dietary supplementation with WPCs on blood parameters, plasma cytokine profiles, and immune cell proliferation and chemotaxis. A total of 45 male mice were equally distributed into three experimental groups and treated daily for 21 days as follows: group I was a control group that was orally supplemented with distilled water, group II was orally supplemented with undenatured WP (100 mg/kg body weight), and group III was orally supplemented with bovine serum albumin (100 mg/kg body weight). We found that the plasma cytokine levels of interleukin (IL)-1α, IL-1β, IL-10 and tumor necrosis factor-α and the levels of reactive oxygen species, cholesterol, triglycerides and the lipid profile were significantly decreased in the WP-treated group compared to the control group. In contrast, the levels of IL-2, IL-4, IL-7, IL-8 and glutathione were significantly elevated, and consequently, the ability of peripheral blood mononuclear cells to proliferate in response to stimulation with different antigens was significantly increased in the WP-treated group. Moreover, the in vitro chemotaxis of B, T and bone-marrow-derived dendritic cells toward CC chemokine ligand-21 and CXC chemokine ligand-12 was significantly increased, by twofold, in WP-treated mice compared to the control group. Taken together, our data reveal the benefits of WP supplementation in enhancing immune cell proliferation and migration to the secondary lymphoid organs.  相似文献   
110.
Multiple myeloma (MM) is a clonal disease of plasma cells that remains incurable despite the advent of several novel therapeutics. In this study, we aimed to delineate the impact of snake venom extracted from Walterinnesia aegyptia (WEV) alone or in combination with silica nanoparticles (WEV+NP) on primary MM cells isolated from patients diagnosed with MM as well as on two MM cell lines, U266 and RPMI 8226. The IC50 values of WEV and WEV+NP that significantly decreased MM cell viability without affecting the viability of normal peripheral mononuclear cells (PBMCs) were determined to be 25 ng/ml and 10 ng/ml, respectively. Although both WEV (25 ng/ml) and WEV+NP (10 ng/ml) decreased the CD54 surface expression without affecting the expression of CXCR4 (CXCL12 receptor) on MM cells, they significantly reduced the ability of CXC chemokine ligand 12 (CXCL12) to induce actin cytoskeleton rearrangement and the subsequent reduction in chemotaxis. It has been established that the binding of CXCL12 to its receptor CXCR4 activates multiple intracellular signal transduction pathways that regulate MM cell chemotaxis, adhesion, and proliferation. We found that WEV and WEV+NP clearly decreased the CXCL12/CXCR4-mediated activation of AKT, ERK, NFκB and Rho-A using western blot analysis; abrogated the CXCL12-mediated proliferation of MM cells using the CFSE assay; and induced apoptosis in MM cell as determined by PI/annexin V double staining followed by flow cytometry analysis. Monitoring the expression of B-cell CCL/Lymphoma 2 (Bcl-2) family members and their role in apoptosis induction after treatment with WEV or WEV+NP revealed that the combination of WEV with NP robustly decreased the expression of the anti-apoptotic effectors Bcl-2, BclXL and Mcl-1; conversely increased the expression of the pro-apoptotic effectors Bak, Bax and Bim; and altered the mitochondrial membrane potential in MM cells. Taken together, our data reveal the biological effects of WEV and WEV+NP and the underlying mechanisms against myeloma cancer cells.  相似文献   
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