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31.

Background  

Ultrahigh-molecular-weight polyethylene (UHMWPE) is used as an articulating surface in prosthetic devices. Its failure under various mechanisms after oxidation is of utmost concern. Free radicals formed during the sterilization process using high-energy irradiation result in oxidation. Europium, an element of the lanthanide family, has a unique electron configuration with an unusual lack of preference for directional bonding and notable bonding to oxygen. Because of this, it currently is used in studies for stabilization of polymers such as polyvinyl chloride.  相似文献   
32.
Diabetic patients are at higher risk of developing physical disabilities than non‐diabetic subjects. Physical disability appears to be related, at least in part, to muscle dysfunction. Several studies have reported reduced muscle strength and power under dynamic and static conditions in both the upper and lower limbs of patients with type 2 diabetes. Additional effects of diabetes include a reduction in muscle mass, quality, endurance and an alteration in muscle fibre composition, though the available data on these parameters are conflicting. The impact of diabetes on neuromuscular function has been related to the co‐existence of long‐term complications. Peripheral neuropathy has been shown to affect muscle by impairing motor nerve conduction. Also, vascular complications may contribute to the decline in muscle strength. However, muscle dysfunction occurs early in the course of diabetes and affects also the upper limbs, thus suggesting that it may develop independently of micro and macrovascular disease. A growing body of evidence indicates that hyperglycaemia may cause an alteration of the intrinsic properties of the muscle to generate force, via several mechanisms. Recently, resistance exercise has been shown to be an effective strategy to counteract the deterioration of muscular performance. High‐intensity exercise seems to provide greater benefits than moderate‐intensity training, whereas the effect of a power training is yet unknown. This article reviews the available literature on the impairment of muscle function induced by diabetes, the underlying mechanisms, and the effect of resistance training on this defect. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
33.
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35.
Fungi belonging to the genus Alternaria are common pathogens of fruit and vegetables with some species able to produce secondary metabolites dangerous to human health. Twenty-eight Alternaria isolates from rocket and cabbage were investigated for their mycotoxin production. Five different Alternaria toxins were extracted from synthetic liquid media and from plant material (cabbage, cultivated rocket, cauliflower). A modified Czapek-Dox medium was used for the in vitro assay. Under these conditions, more than 80% of the isolates showed the ability to produce at least one mycotoxin, generally with higher levels for tenuazonic acid. However, the same isolates analyzed in vivo seemed to lose their ability to produce tenuazonic acid. For the other mycotoxins; alternariol, alternariol monomethyl ether, altenuene and tentoxin a good correlation between in vitro and in vivo production was observed. In vitro assay is a useful tool to predict the possible mycotoxin contamination under field and greenhouse conditions.  相似文献   
36.
The spleen can be affected by several different non-hematopoietic neoplasms as well as pseudoneoplastic lesions. Generally such conditions affect asymptomatic adults and are detected only as incidental findings; in a minority of the cases vague, unspecific symptoms including abdominal discomfort can occur. Most of these conditions present as a “solitary splenic mass” and have been traditionally diagnosed on partial or total splenectomy, which also represents the most common therapeutic strategy; however, the increasing use of splenic needle biopsies for such lesions creates new diagnostic challenges for pathologists. Splenic cysts (including true cysts, pseudocysts and parasitic cysts) and hamartomas are common benign proliferations which generally pose little problems in their identification. More challenging is the diagnostic workup of “spindle cell and inflammatory rich” lesions of the spleen, whose correct identification is crucial. Indeed, some of these are considered reactive (such as sclerosing angiomatoid nodular transformation of the spleen), whilst others are clonal in nature, the main example being represented by the so called “inflammatory pseudotumour- like follicular/fibroblastic dendritic cell sarcoma”. A further degree of complexity is represented by the detection of the Epstein-Barr virus (EBV), which is invariably present in inflammatory pseudotumour- like follicular/fibroblastic dendritic cell sarcoma, but also in other proliferations including the rare “EBV- related smooth muscle tumor of the spleen”. Finally, the spleen can host rare dendritic/reticulum cell sarcomas and metastases from extrasplenic malignancies. The current review aims at highlighting the main histologic features of non-hematopoietic and non-vascular neoplasms as well as pseudoneoplastic lesions of the spleen.  相似文献   
37.

Background

Although the short-term advantages of laparoscopy for colon cancer (CC) over open surgery have been clearly demonstrated, there is little evidence available concerning the long-term outcomes. This study aimed to compare the long-term results of laparoscopic surgery versus open surgery in a cohort of CC patients from a single center.

Methods

A series of 443 patients consecutively operated on for stage I to III CC between January 2006 and December 2013 were followed up. Patients were divided into two groups according to the surgical technique and were compared for disease-free survival (DFS) and overall survival (OS) before and after 1:1 propensity score matching.

Results

Due to exclusions and drop-outs, the statistical analysis of the study is based on 398 patients. Open surgery was performed in 133 patients, and laparoscopic surgery was performed in 265. After propensity score matching, two comparable groups of 89 patients each were obtained. The 5-year DFS was 64.3% and 78.2% for patients in the open and laparoscopic resection groups, respectively [hazard ratio (HR) 0.63, 95% confidence interval (CI) 0.33–1.19; P?=?0.148]. A 5-year OS of 72.1% and 86.8% was observed in the open and laparoscopic resection groups, respectively (HR 0.43, 95%CI 0.20–0.94; P?=?0.026). The multivariate survival analysis demonstrated better results of laparoscopy compared with open surgery for both DFS (HR 0.43, 95%CI 0.23–0.78; P?=?0.004) and OS (HR 0.28, 95%CI 0.14–0.59; P?<?0.001).

Conclusions

Despite the limitations of a retrospective analysis, our study confirms better results for laparoscopic surgery in terms of DFS and OS compared with open surgery in CC treatment.  相似文献   
38.
Clinical and Experimental Medicine - Vasculopathy is a crucial feature of systemic sclerosis (SSc), and Raynaud’s phenomenon (RP) and digital ulcers (DU) have a deep impact on the quality of...  相似文献   
39.
Introduction: Drug discovery and development is a typical multi-objective problem and its successes or failures depend on the simultaneous control of numerous, often conflicting, molecular and pharmacological properties. Multi-objective optimization strategies represent a new approach to capture the occurrence of varying optimal solutions based on trade-offs among the objectives taken into account. In view of this, multi-objective optimization aims to discover a set of satisfactory compromises that may in turn be used to find the global optimal solution by optimizing numerous dependent properties simultaneously. Areas covered: The authors review the potential of multi-objective strategies in a number of fields including: drug library design; substructure mining; the derivation of quantitative structure-activity relationship models; ranking of docking poses. The authors also discuss the potential of multi-objective strategies in controlling competing properties for absorption, distribution, metabolism and elimination/toxicity optimization. Expert opinion: It is very clear to those who work in drug discovery and development that the success of rational drug design is largely dependent on the control of a number of, often conflicting, objectives. Therefore, multi-objective optimization methods, which have recently been introduced to the field of molecular discovery, represent the ultimate frontier in chemoinformatics. The widespread use of these multi-objective techniques has provided new opportunities in medicinal chemistry as seen through its use in a number of applications for chemoinformatics both within academia and the pharmaceutical industry.  相似文献   
40.
Abnormal amyloid-β (Aβ) production and deposition is believed to represent one of the main causes of Alzheimer's disease (AD). γ-Secretase is the enzymatic complex responsible for Aβ generation from its precursor protein. Inhibition or modulation of γ-secretase represents an attractive therapeutic approach. CHF5074 is a new γ-secretase modulator that has been shown to inhibit brain plaque deposition and to attenuate memory deficit in adult AD transgenic mice after chronic treatment. To date, it is not known whether the positive behavioral effects of this compound also occur in young transgenic mice without plaque deposition. Here, we evaluated the effects of acute and subchronic treatment with CHF5074 on contextual and recognition memory and on hippocampal synaptic plasticity in plaque-free Tg2576 mice. We found that at 5 months of age, contextual memory impairment was significantly attenuated after acute subcutaneous administration of 30 mg/kg CHF5074. At 6 months of age, recognition memory impairment was fully reversed after a 4-week oral treatment in the diet (≈60 mg/kg/day). These cognitive effects were associated with a reversal of long-term potentiation (LTP) impairment in the hippocampus. A significant reduction in brain intraneuronal AβPP/Aβ levels and hyperphosphorylated tau, but no change in soluble or oligomeric Aβ levels was detected in Tg2576 mice showing functional recovery following CHF5074 treatment. We conclude that the beneficial effects of CHF5074 treatment in young transgenic mice occurred at a stage that precedes plaque formation and were associated with a reduction in intraneuronal AβPP/Aβ and hyperphosphorylated tau.  相似文献   
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