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91.
Jua (or Joazeiro) is a plant that has been used in Brazil as a folk remedy for many diseases, but mostly as a dentifrice. Several scientific investigations have been conducted in Brazil to examine the therapeutic use of Jua for oral health. This article presents information about the Ziziphus joazeiro plant, its medicinal use, and its chemical components while also reviewing the literature concerning Jua and especially its anti-plaque activity. Although Joazeiro has been investigated, more studies must be performed to better understand these Jua compounds, their antimicrobial activity, and their mechanism of action. Such studies would confirm whether Joazeiro has the potential to fight or prevent diseases like dental caries and periodontitis.  相似文献   
92.
Microcystin-leucine and arginine (microcystin-LR) is a cyanotoxin produced by cyanobacteria like Microcystis aeruginosa, and it’s considered a threat to water quality, agriculture, and human health. Rice (Oryza sativa) is a plant of great importance in human food consumption and economy, with extensive use around the world. It is therefore important to assess the possible effects of using water contaminated with microcystin-LR to irrigate rice crops, in order to ensure a safe, high quality product to consumers. In this study, 12 and 20-day-old plants were exposed during 2 or 7 days to a M. aeruginosa extract containing environmentally relevant microcystin-LR concentrations, 0.26–78 μg/L. Fresh and dry weight of roots and leaves, chlorophyll fluorescence, glutathione S-transferase and glutathione peroxidase activities, and protein identification by mass spectrometry through two-dimensional gel electrophoresis from root and leaf tissues, were evaluated in order to gauge the plant’s physiological condition and biochemical response after toxin exposure. Results obtained from plant biomass, chlorophyll fluorescence, and enzyme activity assays showed no significant differences between control and treatment groups. However, proteomics data indicates that plants respond to M. aeruginosa extract containing environmentally relevant microcystin-LR concentrations by changing their metabolism, responding differently to different toxin concentrations. Biological processes most affected were related to protein folding and stress response, protein biosynthesis, cell signalling and gene expression regulation, and energy and carbohydrate metabolism which may denote a toxic effect induced by M. aeruginosa extract and microcystin-LR. The implications of the metabolic alterations in plant physiology and growth require further elucidation.  相似文献   
93.
Dissemination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in healthcare institutions affects both patients and health-care workers (HCW), as well as the institutional capacity to provide essential health services. Here, we investigated an outbreak of SARS-CoV-2 in a “non-COVID-19” hospital ward unveiled by massive testing, which challenged the reconstruction of transmission chains. The contacts network during the 15-day period before the screening was investigated, and positive SARS-CoV-2 RNA samples were subjected to virus genome sequencing. Of the 245 tested individuals, 48 (21 patients and 27 HCWs) tested positive for SARS-CoV-2. HCWs were mostly asymptomatic, but the mortality among patients reached 57.1% (12/21). Phylogenetic reconstruction revealed that all cases were part of the same transmission chain. By combining contact tracing and genomic data, including analysis of emerging minor variants, we unveiled a scenario of silent SARS-CoV-2 dissemination, mostly driven by the close contact within the HCWs group and between HCWs and patients. This investigation triggered enhanced prevention and control measures, leading to more timely detection and containment of novel outbreaks. This study shows the benefit of combining genomic and epidemiological data for disclosing complex nosocomial outbreaks, and provides valuable data to prevent transmission of COVID-19 in healthcare facilities.  相似文献   
94.

Objectives

This study aims to assess the long-term survival of pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) patients followed in a Portuguese pulmonary hypertension (PH) referral center.

Methods

We studied PAH and CTEPH patients diagnosed between January 2005 and December 2016. Cumulative survival was estimated using the Kaplan-Meier method. Survival trends were compared over two periods (2005-2010 vs. 2011-2016).

Results

Of the 142 studied PH patients (age 54±18 years; 31% male), 47 had CTEPH and 95 had group 1 PH. Most patients with CTEPH and idiopathic/heritable PAH (I/HPAH) were in NYHA III-IV at diagnosis (64% and 57%, respectively). At the time of death, 31% of patients with connective tissue disease (CTD)-associated PAH (CTD-PAH) and all I/HPAH patients were on double or triple combination therapy. No patient underwent lung transplantation. Pulmonary endarterectomy or angioplasty were performed in 36% of CTEPH patients. Age at diagnosis tended to increase over time in CTD-PAH (53±15 vs. 63±15 years; p=0.13) and I/HPAH (39±15 vs. 51±19 years; p=0.10). The five-year survival estimates for I/HPAH, CTD-PAH and CTEPH patients were 80%, 52%, and 81%, respectively. Over time, CTD-PAH and CTEPH showed better five-year survival (33 vs. 67% and 77 vs. 84%), but I/HPAH did not (84 vs. 75%).

Conclusions

Our data indicate a trend toward improved survival over time of CTD-PAH and CTEPH patients treated at a Portuguese referral PH center. Earlier diagnosis, increasing use of parenteral prostanoids, and surgical treatment may further improve PH prognosis.  相似文献   
95.
96.
97.

Objective

The purpose of this study was to evaluate the effect of weight loss induced in morbidly obese subjects by Roux-en-Y gastric bypass bariatric surgery on the atherogenic features of their plasma lipoproteins.

Methods

Twenty-one morbidly obese subjects undergoing bariatric surgery were followed up for up to 1 year after surgery. Plasma and lipoproteins were assayed for chemical composition and lipoprotein-associated phospholipase A2 (Lp-PLA2) activity. Lipoprotein size was assessed by non-denaturing polyacrylamide gradient gel electrophoresis, and oxidised LDL by ELISA. Liver samples were assayed for mRNA abundance of oxidative markers.

Results

Lipid profile analysis revealed a reduction in the plasma concentrations of cholesterol and triglycerides, which were mainly associated with a significant reduction in the plasma concentration of circulating apoB-containing lipoproteins rather than with changes in their relative chemical composition. All patients displayed a pattern A phenotype of LDL subfractions and a relative increase in the antiatherogenic plasma HDL-2 subfraction (>2-fold; P < 0.001). The switch towards predominantly larger HDL particles was due to an increase in their relative cholesteryl ester content. Excess weight loss also led to a significant decrease in the plasma concentration of oxidised LDL (∼−25%; P < 0.01) and in the total Lp-PLA2 activity. Interestingly, the decrease in plasma Lp-PLA2 was mainly attributed to a decrease in the apoB-containing lipoprotein-bound Lp-PLA2.

Conclusion

Our data indicate that the weight loss induced by bariatric surgery ameliorates the atherogenicity of plasma lipoproteins by reducing the apoB-containing Lp-PLA2 activity and oxidised LDL, as well as increasing the HDL-2 subfraction.  相似文献   
98.
99.
Background and Objective: Handgrip strength is a relevant marker of functional status and is also a component of nutrition assessment. The simplicity of this measurement supports its usefulness as a tool to predict who will likely take longer to hospital discharge. The aim of this study was to quantify the association between sex‐specific handgrip strength at hospital admission and time to discharge alive. We intended to include a group of diverse diagnoses and to compare medical and surgical wards, taking into account the potential confounders’ effect of patients’ characteristics and severity of disease. Subjects and Methods: Prospective study in 2 public acute‐care general hospitals in Porto, Portugal, in 2004. Handgrip strength was evaluated using a handgrip dynamometer in a probability sample of 425 patients from medical and surgical wards. The association between baseline handgrip strength and time to discharge was evaluated using survival analysis with discharge alive as the outcome and deaths and transfers being censored. Results: In medical wards, women with high admission handgrip strength had a very short hospital stay (all had been discharged by the sixth day), and among men, patients with low handgrip strength had a particularly longer stay (approximately 50% were discharged after 15 days of hospitalization). In surgical wards, an increasing length of stay with decreasing handgrip strength quartiles was also observed in both sexes. Conclusions: Lower handgrip strength at hospital admission was associated with a longer time in the hospital, in patients of both sexes, in medical and surgical wards. Although this association was explained in part by age, height, education level, cognitive status, and disease severity, its direction remained unchanged regardless of the aforementioned factors.  相似文献   
100.

INTRODUCTION

Chest wall reconstruction due to previous radiation therapy can be challenging and complex, requiring a multidisciplinary approach.

PRESENTATION OF CASE

The authors present the case of a 84-year-old woman with a right chest wall radionecrosis ulcer, that was submitted to an ablative surgery resulting in a full-thickness defect of 224 cm2, firstly reconstructed with a pedicled omental flap. Due to partial flap necrosis, other debridements and chest wall multi-staged flap reconstruction were performed.

DISCUSSION

This case highlights that the reconstructive choice should be individualized and dependent on patient and local factors. The authors advise that surgical team should work closely and be well versed in chest wall reconstruction with a variety of pedicled flaps, when a complication occurs.

CONCLUSION

A multi-staged flap reconstruction could be a salvage procedure for the coverage of complex, great and complicated chest wall defects due to previous radiation therapy.  相似文献   
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