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DNA samples are the fundamental research substrate in genetics. Although methodology and cost-effectiveness in molecular biology have improved dramatically, collecting biological samples and extracting DNA continue to be expensive and time-consuming steps of genetic research. This article reviews the issues surrounding the choice of biological samples for methods of DNA extraction as well as the storage and transport of biological and DNA samples for genetic studies. 相似文献
84.
The purpose of this study was to describe women's perspectives in becoming and being alcohol dependent. Using grounded theory techniques, 14 adult Black and White women receiving treatment for alcohol addiction at rural substance abuse centers participated in an intensive interview. Data analysis focused on the identification of the basic psychosocial problem and the process of becoming alcohol dependent. The results are presented in 2 parts. Part 1, "Alienation From Self and Others," focuses on the basic psychosocial problem faced by women in becoming alcohol dependent. Part 2, "Running Away to Nowhere," on page 142 of this issue of Archives, describes the process used by women to resolve this problem. 相似文献
85.
Using techniques developed in astrophysics to deal with unequally sampled data sets, we have analyzed serial differential cell counts from 45 congenital, idiopathic, and cyclic neutropenic patients before and during treatment with recombinant human G-CSF (rhG-CSF). Our results show that the occurrence of significant cycling in the absolute neutrophil count (ANC) of neutropenics not classified as cyclical is much more prevalent than had been previously thought, and that not all the patients classified as cyclic show significant ANC periodicity. In these patients, cycling in more than one cell line may be involved. The range of periods encountered in these patients is much broader (between 11 and 52 days) than is usually associated with classical cyclical neutropenia, and there is no obvious connection between the range of periods and the patient's diagnostic category. Administration of rhG-CSF is able to induce significant cycling in neutropenic patients that were not cycling prior to treatment. In patients who had significant cycling before treatment, rhG-CSF may either decrease the period to between 11 and 14 days, or may obliterate any statistical evidence of cycling. 相似文献
86.
Periodic chronic myelogenous leukaemia: spectral analysis of blood cell counts and aetiological implications 总被引:1,自引:0,他引:1
Of 24 published clinical reports of periodic chronic myelogenous leukaemia (PCML), 21 had sufficient data to analyse for periodicity, and 12 showed significant periodicity (p < or = 0.05) using the Lomb periodogram. Leucocyte oscillations had periods T ranging from 37 to 83d. When data were also reported for platelets and reticulocytes there was no significant difference between their periods and those of the leucocytes. These data and their analysis provide strong circumstantial evidence for a haemopoietic stem cell origin of PCML. Namely, the known chromosomal changes in CML patients may, on occasion, also be accompanied by a destabilization resulting in an oscillatory efflux into the leucocyte, platelet and erythrocytic pathways. 相似文献
87.
Chronic, low-dose prenatal exposure to methylmercury impairs motor and mnemonic function in adult C57/B6 mice 总被引:2,自引:0,他引:2
Montgomery KS Mackey J Thuett K Ginestra S Bizon JL Abbott LC 《Behavioural brain research》2008,191(1):55-61
Methylmercury (MeHg) has cytotoxic effects on animals and humans, and a major target organ for MeHg is the central nervous system (CNS). It is well known that the developing CNS is extremely vulnerable to MeHg-induced changes in comparison to the mature brain. Most studies have concentrated on the direct effects of high levels of prenatal MeHg exposure. Surprisingly, behavioral outcomes found in adult offspring exposed developmentally to the neurotoxic effects of chronic, low-dose mercury more akin to ingestion in humans are not well characterized. The objective of this study was to determine whether such exposure produces deleterious effects on behavior in adult mice, including motor/coordination abilities, overall activity and mnemonic function. Developing mouse fetuses were exposed in utero during gestational days 8-18 by giving pregnant C57Bl/6J female mice food containing MeHg at a daily dose of 0.01 mg/kg body weight. Adult mice prenatally exposed to MeHg exhibited significant deficits in motor abilities, coordination, and overall activity, as measured by rotarod, footprint analysis and open field. In addition, MeHg-exposed mice were impaired with respect to reference memory but not in a visible, cued version of the Morris water maze task. These results indicate that prenatal exposure to the lowest dose of MeHg examined to date can have long-lasting motor and cognitive consequences on adult offspring. These findings have far reaching implications related to putative safe levels of MeHg ingestion, particularly during pregnancy, and increasing rates of cognitive and psychological disorders (e.g. attention hyperactivity deficit disorder, autism) in our society. 相似文献
88.
89.
Simon Doessing Katja M. Heinemeier Lars Holm Abigail L. Mackey Peter Schjerling Michael Rennie Kenneth Smith Søren Reitelseder Anne-Marie Kappelgaard Michael Højby Rasmussen Allan Flyvbjerg Michael Kjaer 《The Journal of physiology》2010,588(2):341-351
In skeletal muscle and tendon the extracellular matrix confers important tensile properties and is crucially important for tissue regeneration after injury. Musculoskeletal tissue adaptation is influenced by mechanical loading, which modulates the availability of growth factors, including growth hormone (GH) and insulin-like growth factor-I (IGF-I), which may be of key importance. To test the hypothesis that GH promotes matrix collagen synthesis in musculotendinous tissue, we investigated the effects of 14 day administration of 33–50 μg kg−1 day−1 recombinant human GH (rhGH) in healthy young individuals. rhGH administration caused an increase in serum GH, serum IGF-I, and IGF-I mRNA expression in tendon and muscle. Tendon collagen I mRNA expression and tendon collagen protein synthesis increased by 3.9-fold and 1.3-fold, respectively ( P < 0.01 and P = 0.02), and muscle collagen I mRNA expression and muscle collagen protein synthesis increased by 2.3-fold and 5.8-fold, respectively ( P < 0.01 and P = 0.06). Myofibrillar protein synthesis was unaffected by elevation of GH and IGF-I. Moderate exercise did not enhance the effects of GH manipulation. Thus, increased GH availability stimulates matrix collagen synthesis in skeletal muscle and tendon, but without any effect upon myofibrillar protein synthesis. The results suggest that GH is more important in strengthening the matrix tissue than for muscle cell hypertrophy in adult human musculotendinous tissue. 相似文献
90.
Adrian YS Yip WP Chu Louis WC Chow Wings TY Loo Eleanor YY Ong Wincy Chan 《中华乳腺病杂志(电子版)》2011,5(6):646-659
Breast cancer is one of the leading causes of cancer deaths among women[1].In the past 40 years,breast cancer incidence has doubled or even tripled in developed countries such as South Korea and Japan; whereas it is about 20% to 30% in China and India in the past decade[2-4]. An increasing incidence rate of 3% 相似文献