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91.
An overview on in situ micronization technique – An emerging novel concept in advanced drug delivery
K.R. Vandana Y. Prasanna Raju V. Harini Chowdary M. Sushma N. Vijay Kumar 《Saudi Pharmaceutical Journal》2014,22(4):283-289
The use of drug powders containing micronized drug particles has been increasing in several pharmaceutical dosage forms to overcome the dissolution and bioavailability problems. Most of the newly developed drugs are poorly water soluble which limits dissolution rate and bioavailability. The dissolution rate can be enhanced by micronization of the drug particles. The properties of the micronized drug substance such as particle size, size distribution, shape, surface properties, and agglomeration behaviour and powder flow are affected by the type of micronization technique used. Mechanical communition, spray drying and supercritical fluid (SCF) technology are the most commonly employed techniques for production of micronized drug particles but the characteristics of the resulting drug product cannot be controlled using these techniques. Hence, a newer technique called in situ micronization is developed in order to overcome the limitations associated with the other techniques. This review summarizes the existing knowledge on in situ micronization techniques. The properties of the resulting drug substance obtained by in situ micronization were also compared. 相似文献
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Anita Saxena 《Global Heart》2013,8(3):203-212
Rheumatic heart disease continues to be a significant public health problem in many developing countries and in some of the aboriginal populations in developed countries. Echocardiography has become indispensable in the assessment of valve lesions secondary to rheumatic heart disease. It confirms the rheumatic etiology of valvular abnormality as the features are quite typical in most cases. It also helps to exclude nonrheumatic causes of valve lesions. M-mode and cross-sectional echo helps to assess the severity of valve abnormality and its hemodynamic effects on the heart. Further, color flow imaging evaluates the flow across a valve, both qualitatively and quantitatively. Serial echocardiography plays a crucial role in the follow-up of patients with rheumatic heart disease and is very helpful for determining the timing of intervention. Recently, addition of real-time 3-dimensional echocardiography has further improved imaging of cardiac valves, especially the mitral valve. 相似文献
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Jagjeet Singh Sahil Sharma A. K. Saxena Kunal Nepali Preet Mohinder Singh Bedi 《Medicinal chemistry research》2013,22(7):3160-3169
In view of the drug resistance with most of the currently used anticancer drugs, molecular hybrids of pyrazolyl chalcones and p-nitro benzyl functionalities tethered by triazole ring have been synthesised and evaluated for cytotoxic studies against three human cancer cell lines (THP, COLO-205, A-549). The results of the preliminary investigation exhibited marked dependence of the cytotoxic activity on the electronic factors. Placement of naphthyl (JGPT-11) and trimethoxy phenyl ring (JGPT-6) as ring A proved to be extremely beneficial in enhancing the cytotoxic potential. Thus we herein report the synthesis and cytotoxic studies of a new class of molecular hybrids. Detailed investigation on the biological mechanistic insights of JGPT-11 and 6 is under progress. 相似文献
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Kushaljit Singh Sodhi Akshay Kumar Saxena Niranjan Khandelwal Y. K. Chawla 《The Indian journal of surgery》2014,76(5):413-414
Pseudolipoma of inferior vena cava refers to a normal variant of adipose collection that is seen in typical pericaval or juxtacaval location; however, it mimics an intracaval mass lesion, especially fat-containing lesions such as lipoma. Awareness of this entity is very important to avoid misdiagnosis and unnecessary diagnostic procedures. 相似文献
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Lauren A. E. Erland Mukund R. Shukla Amritpal S. Singh Susan J. Murch Praveen K. Saxena 《Journal of pineal research》2018,64(2)
Melatonin and serotonin are important signaling and stress mitigating molecules that play important roles across growth and development in plants. Despite many well‐documented responses, a systematic investigation of the entire metabolic pathway (tryptophan, tryptamine, and N‐acetylserotonin) does not exist, leaving many open questions. The objective of this study was to determine the responses of Hypericum perforatum (L.) to melatonin, serotonin, and their metabolic precursors. Two well‐characterized germplasm lines (#4 and 112) created by mutation and a haploid breeding program were compared to wild type to identify specific responses. Germplasm line 4 has lower regenerative and photosynthetic capacity than either wild type or line 112, and there are documented significant differences in the chemistry and physiology of lines 4 and 112. Supplementation of the culture media with tryptophan, tryptamine, N‐acetylserotonin, serotonin, or melatonin partially reversed the regenerative recalcitrance and growth impairment of the germplasm lines. Quantification of phytohormones revealed crosstalk between the indoleamines and related phytohormones including cytokinin, salicylic acid, and abscisic acid. We hypothesize that melatonin and serotonin function in coordination with their metabolites in a cascade of phytochemical responses including multiple pathways and phytohormone networks to direct morphogenesis and protect photosynthesis in H. perforatum. 相似文献
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Sandul Yasobant Walter Bruchhausen Deepak Saxena Timo Falkenberg 《Health research policy and systems / BioMed Central》2018,16(1):124
The complexity and increasing burden of zoonotic diseases create challenges for the health systems of developing nations. Public health systems must therefore be prepared to face existing and future disease threats at the human–animal interface. The key for this is coordinated action between the human and the animal health systems. Although some studies deal with the question of how these two systems interact during unforeseen circumstances such as outbreaks, a dearth of literature exists on how these systems interact on early detection, prevention and control of zoonotic diseases; assessing this problem from the health system perspective in a developing nation adds further complexity. Systems thinking is one of the promising approaches in understanding the factors that influence the system’s complexity and dynamics of health maintenance. Therefore, this study aims to understand the generic structure and complexity of interaction between these actors within the domain of One Health for the effectual prevention and control of zoonotic diseases in India.The present study will be executed in Ahmedabad, located on the Western part of India, in Gujarat state, using a mixed methods approach. For the first step, zoonotic diseases will be prioritised for the local context through semi-quantitative tools. Secondly, utilising semi-structured interviews, stakeholders from the human and animal health systems will be identified and ranked. Thirdly, the identified stakeholders will be questioned regarding the current strength of interactions at various levels of the health system (i.e. managerial, provider and community level) through a quantitative network survey. Fourthly, utilising a vignette method, the ideal convergence strategies will be documented and validated through policy Delphi techniques. Finally, through a participatory workshop, the factors that influence convergence for the control and prevention of zoonotic diseases will be captured.This study will provide a comprehensive picture of the current strength of collaboration and network depth at various levels of the health system. Further, it will assist different actors in identifying the relevance of possible One Health entry points for participation, i.e. it will not only contribute but will also develop a system convergence model for the effectual prevention and control of zoonotic diseases. 相似文献