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991.
Gentianopsis paludosa (Hook. f.) Ma (Gentianaceae) is an important species in Tibetan folk medicine commonly used to clear away the "heat evils" and toxic materials. A survey of market samples revealed that nine adulterant species, Gentianopsis barbata, G. contorta, G. grandis, Halenia elliptica, Lomatogonium macranthum, L.rotatum, Swertia angustifolia, S. bifolia and S. erythrosticta, are often marketed as G. paludosa. Methods to distinguish G. paludosa from its adulterants are limited by current morphological and chemical methods. DNA sequence analysis of the nuclear ribosomal DNA internal transcribed spacer region (ITS) was used in the differentiation of G.paludosa from the adulterant species. The data showed that the internal transcribed spacer regions differ significantly between G. paludosa and all nine adulterant species, so that they could be easily distinguished at the DNA level.  相似文献   
992.
Introduction – It is estimated that about 70–80% of the world's population relies on non‐conventional medicine, mainly of herbal origin. However, owing to the nature and sources of herbal medicines, they are sometimes contaminated with toxic heavy metals such as lead, arsenic, mercury and cadmium, which impose serious health risks to consumers. It is critical to analyse source materials for heavy metals in order to ensure that their concentrations meet the related standards or regulations limiting their concentrations in herbal medicines. In this review, different analytical methods for analysis of heavy metals in herbal medicines are discussed. Objective – To provide a comprehensive review of the current state of the art in analytical methods used to detect heavy metals in herbal medicines. Methodology – We systematically searched and reviewed the research articles regarding analytical methods for heavy metals in herbal medicine from various databases, such as Medline/PubMed, ScienceDirect, SciFinder, Google Scholar, EBSCO, Gale InfoTrac, Ingenta, Ovid, ProQuest and ISI Web of Knowledge. Results – In this review, we discuss in detail several commonly used and sensitive analytical techniques, including atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry or mass spectrometry, X‐ray fluorescence spectrometry, high‐performance liquid chromatography, differential pulse polarography, neutron activation analysis and anodic stripping voltammetry. We also provide some application examples of these analytical techniques for heavy metals in herbal medicines. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
993.

Background

Case reports provide essential information on adverse effects. Yet there is little consistency in the quality and format of reporting them.

Aim

In this study, we aimed to assess the quality of case reports of adverse effect of herbal medicinal products (HMPs) published during three time periods, 1986-1988, 1996-1998, and 2006-2008.

Methods

We conducted literature searches in four major databases: Medline, EMBASE, AMED, and CINALH. Each case report was subject to specific inclusion criteria related to the intervention (i.e. herbal medicine) and outcome measurement (i.e. adverse effect). A 21-item scale was used to assess the quality of all included reports. Each report was categorised into low quality (score between 0 and 14), lower medium quality (score between 15 and 21), upper medium quality (score between 22 and 28), and high quality (score between 29 and 42).

Results

In total, 137 case reports were included. The percentage of high quality case reports rose from 0% in 1986-1988 to 27.9% in 1996-1998 and 34.2% in 2006-2008; conversely, the percentages of low quality case reports dropped from 13.3% in 1986-1988 to 0% in 1996-1998 and 2.5% in 2006-2008.

Conclusion

These findings are consistent with the notion that the quality of case reports is improving. However, due to several caveats, our data should be interpreted with caution.  相似文献   
994.
Held on November 19, 2012 in Saint-Cyr-sur-Loire, France, the symposium “From Bretonneau to therapeutic antibodies, from specificity to specific remedies” focused on the historical development of antibodies as therapeutics, with an emphasis on the seminal work of the French physician Pierre-Fidèle Bretonneau (1778–1862). The morning session was devoted to discussion of the evolution of the concept of specificity in medicine, which started with an epistemological definition. The contributions of Bretonneau to the emergence of the concept of specificity, notably with his studies on diphtheria, and the subsequent development of antidiphtheric serotherapy in Europe during the period 1894–1898 were then presented in detail. The afternoon session began with a presentation on the role of French physiologists during the years 1860–1890 in establishing the basic concepts of specific immunity and the principles of serotherapy. The history of antivenom serotherapy, particularly its discovery by Césaire Phisalix, and the development of antilymphocyte globulins as successful transplantation drugs were then discussed. The symposium ended with the inauguration of a stele representing Bretonneau, who lived in Saint-Cyr-sur-Loire and died 150 y ago.  相似文献   
995.
Glioblastoma (GBM) is the most common and aggressive primary brain tumor in adults. GBM cells are highly resistant to apoptosis induced by antitumor drugs and radiotherapy resulting in cancer progression. We assessed whether a systems medicine approach, analysing the ability of tumor cells to execute apoptosis could be utilized to predict the response of GBM patients to treatment. Concentrations of the key proapoptotic proteins procaspase-3, procaspase-9, Smac and Apaf-1 and the antiapopotic protein XIAP were determined in a panel of GBM cell lines and GBM patient tumor resections. These values were used as input for APOPTO-CELL, a systems biological based mathematical model built to predict cellular susceptibility to undergo caspase activation. The modeling was capable of accurately distinguishing between GBM cells that die or survive in response to treatment with temozolomide in 10 of the 11 lines analysed. Importantly the results obtained using GBM patient samples show that APOPTO-CELL was capable of stratifying patients according to their progression-free survival times and predicted the ability of tumor cells to support caspase activation in 16 of the 21 GBM patients analysed. Calculating the susceptibility to apoptosis execution may be a potent tool in predicting GBM patient therapy responsiveness and may allow for the use of APOPTO-CELL in a clinical setting.  相似文献   
996.
997.
The use of orthobiologics as a novel therapy for the treatment of numerous musculoskeletal disorders has increased considerably over the past decade.Currently,there are multiple alternatives available as suitable treatments;however,the use of autologous blood-derived products such as platelet-rich plasma(PRP),bone marrow aspirate(BMA)and BMA concentrate(BMAC),specifically,is expanding.Although many investigations attempted to demonstrate the effectiveness of these therapies,even with positive results,the literature lacks standardized protocols and overall accuracy in study designs,which leads to variance and difficulty in reproducibility of protocols.The efficacy of PRP for the treatment of cartilage,bone and muscle tissues is well known.Although BMAC has generated optimistic results for the same purposes,its applicability in clinical trials is still relatively recent when compared to PRP.Both products demonstrate the potential to set forth reparative processes,each in their own distinct mechanism.The combination of these biological products has been previously proposed,yet little is known about their synergism.Evidence indicates that growth factor,cytokine,and chemokine profiles seen in both PRP and BMAC vary but are likely to work synergistically to enhance musculoskeletal healing.BMAC products seem to work well without PRP;however,the addition of PRP to BMAC has been shown to act as a rich and natural source of culture medium for stem cells located either peripherally or in the bone marrow itself.Nevertheless,additional variables associated with the use of BMAC and PRP in orthopedics must be further evaluated in order to consolidate the efficacy of this therapeutic strategy.  相似文献   
998.
Stem cell-based treatments have been extensively explored in the last few decades to develop therapeutic strategies aimed at providing effective alternatives for those human pathologies in which surgical or pharmacological therapies produce limited effects. Among stem cells of different sources, mesenchymal stem cells (MSCs) offer several advantages, such as the absence of ethical concerns, easy harvesting, low immunogenicity and reduced tumorigenesis risks. Other than a multipotent differentiation ability, MSCs can release extracellular vesicles conveying proteins, mRNA and microRNA. Thanks to these properties, new therapeutic approaches have been designed for the treatment of various pathologies, including ocular diseases. In this review, the use of different MSCs and different administration strategies are described for the treatment of diabetic retinopathy, glaucoma, and retinitis pigmentosa. In a large number of investigations, positive results have been obtained by in vitro experiments and by MSC administration in animal models. Most authors agree that beneficial effects are likely related to MSC paracrine activity. Based on these considerations, many clinical trials have already been carried out. Overall, although some adverse effects have been described, promising outcomes are reported. It can be assumed that in the near future, safer and more effective protocols will be developed for more numerous clinical applications to improve the quality of life of patients affected by eye diseases.  相似文献   
999.
The objective of our study was to study the effect of danshen, a Chinese herbal medicine known to prevent hypertension, on the zero-stress state of rat's abdominal aorta. The zero-stress state of a blood vessel represents the release of residual stress on the vessel wall, and is the basic configuration of blood vessel affected solely by intrinsic parameters. At the in vivo state, the rat's abdominal aorta was subjected to blood pressure and flow and longitudinal stress. After dissecting from the abdominal aorta, the aortic specimens were cut into small rings at no-load state, in which the internal pressure, external pressure, and longitudinal stress in a short ring-shaped segment were all zero; by cutting radially to release the residual stress in the wall, the vessel ring opened up into a sector quickly, and the sector's configuration would not change at 20 min after cutting and was defined as the zero-stress state of a blood vessel, which was characterized by its residual strain and opening angle. Then aqueous extract of danshen prepared with methanol was added in the Krebs solution, and the changes of the aorta's zero-stress state were monitored by taking photos routinely for analysis to determine the opening angle and residual strain. Additionally, other sets of samples were tested in a Norepinephrine-Krebs solution as positive control or a Krebs solution as negative control, respectively. It was demonstrated that the zero-stress state of rat's abdominal aorta was affected by danshen extract and norepinephrine in two different patterns, while the Krebs solution did not have similar effects. The present work provides a new approach to study the anti-hypertension effect and mechanism of danshen.  相似文献   
1000.
Abstract

The limited regenerative capacity of articular cartilage and deficiencies of current treatments have motivated the investigation of new repair technologies. In vitro cartilage generation using primary cell sources is limited by cell availability and expansion potential. Pluripotent stem cells possess the capacity for chondrocytic differentiation and extended expansion, providing a potential future solution to cell-based cartilage regeneration. However, despite successes in producing cartilage using adult and embryonic stem cells, the translation of these technologies to the clinic has been severely limited. This review discusses recent advances in stem cell-based cartilage tissue engineering and the major current limitations to clinical translation of these products. Concerns regarding appropriate animal models and studies, stem cell manufacturing, and relevant regulatory processes and guidelines will be addressed. Understanding the significant hurdles limiting the clinical use of stem cell-based cartilage may guide future developments in the fields of tissue engineering and regenerative medicine.  相似文献   
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