全文获取类型
收费全文 | 857篇 |
免费 | 50篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 15篇 |
妇产科学 | 25篇 |
基础医学 | 127篇 |
口腔科学 | 24篇 |
临床医学 | 38篇 |
内科学 | 287篇 |
皮肤病学 | 24篇 |
神经病学 | 35篇 |
特种医学 | 25篇 |
外科学 | 149篇 |
综合类 | 4篇 |
预防医学 | 24篇 |
眼科学 | 12篇 |
药学 | 25篇 |
肿瘤学 | 98篇 |
出版年
2023年 | 6篇 |
2022年 | 16篇 |
2021年 | 19篇 |
2020年 | 11篇 |
2019年 | 18篇 |
2018年 | 20篇 |
2017年 | 23篇 |
2016年 | 21篇 |
2015年 | 24篇 |
2014年 | 31篇 |
2013年 | 44篇 |
2012年 | 95篇 |
2011年 | 51篇 |
2010年 | 27篇 |
2009年 | 27篇 |
2008年 | 57篇 |
2007年 | 48篇 |
2006年 | 54篇 |
2005年 | 28篇 |
2004年 | 35篇 |
2003年 | 40篇 |
2002年 | 37篇 |
2001年 | 15篇 |
2000年 | 12篇 |
1999年 | 12篇 |
1998年 | 7篇 |
1997年 | 9篇 |
1996年 | 13篇 |
1995年 | 2篇 |
1994年 | 11篇 |
1993年 | 5篇 |
1992年 | 16篇 |
1991年 | 15篇 |
1990年 | 11篇 |
1989年 | 11篇 |
1988年 | 11篇 |
1987年 | 4篇 |
1986年 | 8篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 3篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1965年 | 3篇 |
1961年 | 1篇 |
排序方式: 共有920条查询结果,搜索用时 15 毫秒
1.
The hemolysin-producer coelomocytes in Holothuria polii 总被引:1,自引:0,他引:1
Calogero Canicatti Donatella Ciulla Elvira Farinalipari 《Developmental and comparative immunology》1988,12(4):729-736
Using sodium metrizoate discontinuous gradients, two hemolysin-producer amebocyte populations have been separated from total circulating Holothuria polii coelomocytes. The amebocytes of population 1 are responsible for the production of the calcium-dependent and temperature-labile hemolysin, whereas those of population 2 produce the calcium-independent and temperature-stable one. The intracytoplasmic hemolysins were evidenced also by immunofluorescence. Petaloid and filipodial amebocytes were the only positive cell types. 相似文献
2.
Ilaria Capua Calogero Terregino Giovanni Cattoli Franco Mutinelli J.F. Rodriguez 《Avian pathology》2003,32(1):47-55
The present paper reports of the development and validation of a control strategy for avian influenza infections in poultry. The "DIVA" (Differentiating Infected from Vaccinated Animals) strategy is based on the use of an inactivated oil emulsion vaccine containing the same haemagglutinin (H) subtype as the challenge virus, but a different neuraminidase (N). The possibility of using the heterologous N subtype, to differentiate between vaccinated and naturally infected birds, was investigated through the development of an "ad hoc" serological test based on the detection of specific anti-N1 antibodies. This was achieved using a baculovirus expressing a recombinant N1 protein. The A/ck/Pakistan/H7N3 virus was used as a vaccine and birds were challenged with the HPAI A/ty/Italy/4580/V99/H7N1 strain. The homologous H group ensured a clinical protection of 93% regardless of the vaccination scheme used, and was able to prevent viraemia and muscle colonization in the clinically healthy challenged birds. However, it was not able to prevent viral shedding. The "ad hoc" serological assay was developed as an indirect immunofluorescence test, and was validated using 608 field sera, and showed an "almost perfect agreement" (Kappa value) with the HI test, with relative sensitivity and specificity values of 98.1 and 95.7, respectively. The results of the present investigation suggest that the "DIVA" control strategy may represent a tool for the control of avian influenza infections in poultry. 相似文献
3.
encapsulating structures occurred inHolothuria tubulosa. Histologically, they were formed by nodules entrapping foreign material. By an internodular mass, two or more nodules were assembled in an encapsulating body that was brown-pigmented. This pigment could be melanin, since an enzyme (i.e., phenoloxidase) responsible for its synthesis was proven. The enzyme exerted oxidase activity against dopa, dopamine and norepinephrine but not against tyrosine. The components of the sea-cucumber phenoloxidase-activating system were present in the circulating cells, which could therefore be responsible for melanin deposition during processes of foreign-body encapsulation. 相似文献
4.
5.
Calogero Caruso Patrizia Palmeri Lorenzo Oliva Ambrogio Orlando Mario Cottone 《Tissue antigens》1985,25(1):47-49
HLA antigens were investigated in 41 Sicilian patients with ulcerative colitis and in 151 healthy controls. Frequencies of HLA-B5 and DR2 were increased in the group of patients with ulcerative colitis whereas the DR3 antigen frequency was decreased. However the corrected p values were not significant. Thus, present results indicate that in ulcerative colitis HLA linked genetic factors play a marginal role, if any. 相似文献
6.
Calogero Caruso Giuseppina Candore Diego Cigna Gabriele Di Lorenzo Guido Sireci Francesco Dieli Alfredo Salerno 《Immunologic research》1996,15(1):84-90
It is well known that aging is associated with various alterations in lymphoid cell functions, particularly with a progressive decline in immune responsiveness to exogenous antigens and increasing incidence of autoimmune phenomena. Many studies have been focused on the mechanisms of the immunologic features of aging. This review describes our results of studies performed to determine the influence of age on the capacity to produce interleukin-2 (IL-2), interferon-γ (IFN-γ), interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin-6 (IL-6) and tumor necrosis factor (TNF). Mitogen-stimulated cultures of mononuclear cells (MNC) from human beings were assessed for cytokine-producing capacity. A significant decrease in IFN-γ and IL-2 production by MNC cultures from elderly individuals was observed. No significant difference was instead observed between cultures from elderly individuals and those from young ones as regards TNF-α, IL-4 and IL-6 production. Mitogen or antigen-stimulated cultures of MNC from aged mice also displayed a significant decrease in IFN-γ and IL-2 production as well as TNF-β. Instead IL-4 and IL-5 production significantly increased in these cultures. We suggest that this imbalanced cytokine production may well account for the pattern of immune response which may be observed in the elderly, i.e. a normal or increased humoral response (including autoimmune responses) in face of a low T cell immune responsiveness. 相似文献
7.
Calogera Pisano Daniele Polisano Carmela Rita Balistreri Claudia Altieri Paolo Nardi Fabio Bertoldo Daniele Trombetti Laura Asta Maria Sabrina Ferrante Dario Buioni Calogero Foti Giovanni Ruvolo 《Nutrients》2021,13(2)
Frailty is the major expression of accelerated aging and describes a decreased resistance to stressors, and consequently an increased vulnerability to additional diseases in elderly people. The vascular aging related to frail phenotype reflects the high susceptibility for cardiovascular diseases and negative postoperative outcomes after cardiac surgery. Sarcopenia can be considered a biological substrate of physical frailty. Malnutrition and physical inactivity play a key role in the pathogenesis of sarcopenia. We searched on Medline (PubMed) and Scopus for relevant literature published over the last 10 years and analyzed the strong correlation between frailty, sarcopenia and cardiovascular diseases in elderly patient. In our opinion, a right food intake and moderate intensity resistance exercise are mandatory in order to better prepare patients undergoing cardiac operation. 相似文献
8.
9.