全文获取类型
收费全文 | 970篇 |
免费 | 45篇 |
国内免费 | 3篇 |
专业分类
儿科学 | 72篇 |
妇产科学 | 11篇 |
基础医学 | 124篇 |
口腔科学 | 26篇 |
临床医学 | 97篇 |
内科学 | 225篇 |
皮肤病学 | 21篇 |
神经病学 | 19篇 |
特种医学 | 250篇 |
外科学 | 51篇 |
综合类 | 12篇 |
预防医学 | 36篇 |
眼科学 | 7篇 |
药学 | 28篇 |
中国医学 | 1篇 |
肿瘤学 | 38篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 3篇 |
2018年 | 11篇 |
2017年 | 9篇 |
2016年 | 7篇 |
2015年 | 10篇 |
2014年 | 15篇 |
2013年 | 16篇 |
2012年 | 17篇 |
2011年 | 12篇 |
2010年 | 33篇 |
2009年 | 42篇 |
2008年 | 26篇 |
2007年 | 13篇 |
2006年 | 17篇 |
2005年 | 13篇 |
2004年 | 19篇 |
2003年 | 17篇 |
2002年 | 13篇 |
2001年 | 17篇 |
2000年 | 12篇 |
1999年 | 19篇 |
1998年 | 49篇 |
1997年 | 65篇 |
1996年 | 49篇 |
1995年 | 44篇 |
1994年 | 50篇 |
1993年 | 51篇 |
1992年 | 14篇 |
1991年 | 15篇 |
1990年 | 14篇 |
1989年 | 41篇 |
1988年 | 41篇 |
1987年 | 32篇 |
1986年 | 28篇 |
1985年 | 26篇 |
1984年 | 13篇 |
1983年 | 22篇 |
1982年 | 17篇 |
1981年 | 19篇 |
1980年 | 22篇 |
1979年 | 6篇 |
1978年 | 9篇 |
1977年 | 13篇 |
1976年 | 9篇 |
1975年 | 18篇 |
1973年 | 2篇 |
1967年 | 1篇 |
1948年 | 1篇 |
排序方式: 共有1018条查询结果,搜索用时 15 毫秒
71.
The hematopoietic stem cells of alpha-thalassemic mice 总被引:1,自引:0,他引:1
The alpha-thalassemic mouse has a hereditary microcytic anemia, almost certainly has a shortened RBC life span, and is a potential candidate for cell replacement therapy. In a routine study of bone marrow repopulating capacity using hemoglobin as a cell marker, normal donor marrow cells, but not alpha-thalassemic donor marrow cells, completely replaced the host cells. Further analysis showed that at least 30 times more alpha-thalassemic cells were required to outcompete normal donor cells injected simultaneously. The results were more extreme then expected and suggested a defect in a stem cell population as well as in the RBCs. Evidence that the multipotent and erythroid-committed stem cells in alpha-thalassemic mice are not decreased was shown by CFU-S and CFU-E assays. The combined results indicate that the deletion expresses itself most conspicuously in the RBC population. Tests were also performed to analyze repopulation kinetics in the Hbath-J/+ mice. In unirradiated alpha-thalassemic hosts, the hemoglobin from a normal donor persisted but did not replace the host hemoglobin. Sublethally irradiated alpha-thalassemic hosts, on the other hand, were easily repopulated with normal cells. We conclude that the alpha-thalassemic mouse is a good model for cell replacement therapy. 相似文献
72.
Preliminary evidence for a role of apolipoprotein E alleles in identifying haemodialysis patients at high vascular risk 总被引:1,自引:0,他引:1
Olmer M; Renucci JE; Planells R; Bouchouareb D; Purgus R 《Nephrology, dialysis, transplantation》1997,12(4):691-693
Conventional risk factors have very low predictive power in identifying
haemodialysis patients at high risk of vascular accidents. A role for
apolipoprotein E isotypes was looked for in a small, but rigorously
defined, cohort of longterm haemodialysis patients. In individuals with
high vascular risk, as identified by higher common carotid intima/media
thickness, we found an excess of apolipoprotein E4 alleles. This
preliminary result requires confirmation in large patient cohorts.
相似文献
73.
Christopher B. Pattillo Berenice Venegas Fred J. Donelson Luis Del Valle Linda C. Knight Parkson L.-G. Chong Mohammad F. Kiani 《Pharmaceutical research》2009,26(5):1093-1100
Purpose Radiation upregulates expression of endothelial cell adhesion molecules providing a potential avenue for targeting drugs to
irradiated tissue. Induced upregulation of E-selectin can be used to target immunoliposomes to solid tumors. The effects of
targeting immunoliposomes containing the antivascular drug combretastatin disodium phosphate (CA4P) to irradiated mammary
tumors were investigated in this study.
Methods Mice bearing transplanted MCa-4 mouse mammary tumors were assigned to one of the factorial treatments permuting the administration
of free CA4P, tumor irradiation, CA4P encapsulated liposomes, and CA4P encapsulated immunoliposomes (conjugated with anti-E-selectin).
Single and fractionated dosing of radiation and/or CA4P was evaluated.
Results For single dose treatments the group that received a single dose of radiation plus a single dose of immunoliposomes showed
a significant delay in tumor growth compared to all other treatment groups. Fractionated radiation plus fractionated doses
of immunoliposomes resulted in further tumor growth delay; however, it was not significantly different from other fractionated
dose treatment groups that combined radiation and CA4P.
Conclusions Targeting of antivascular drugs to irradiated tumors via ligand-bearing liposomes results in significant tumor growth delay. This effect can be further potentiated using a fractionated
irradiation dosing schedule combined with fractionated immunoliposome treatments.
CBP and BV made equal contribution to this work. 相似文献
74.
75.
76.
A Nørremølle E Budtz-Jørgensen K Fenger JE Nielsen SA Sørensen and L Hasholt 《Clinical genetics》2009,75(3):244-250
Huntington disease (HD) is caused by an expanded CAG repeat sequence in the HD gene. Although the age at onset is correlated to the CAG repeat length, this correlation only explains approximately half of the variation in onset age. Less variation between siblings indicates that the variation is, in part, explained by genetic modifiers. We analyzed polymorphic loci within or close to the HD gene on the HD chromosome in Danish HD patients. We found one specific haplotype segregating with later age at onset, compared with patients with similar CAG repeat length and another haplotype. The nine Danish families in the study carrying this haplotype most likely have a common founder. Several of the polymorphic loci displayed alleles that may be specific to the late-onset haplotype, implicating that from this study we cannot determine which of the loci tested (or other polymorphic loci in this chromosomal area) do in fact contain genetic modifiers of age at onset. 相似文献
77.
78.
79.
Moore AD; Godwin JD; Muller NL; Naidich DP; Hammar SP; Buschman DL; Takasugi JE; de Carvalho CR 《Radiology》1989,172(1):249-254
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities. 相似文献
80.
Among 600 infants examined with ultrasound for vomiting, seven (mean age, 3 months) had distinctive features that can be considered diagnostic of gastric ulcer. The findings are thickening of the mucosa (greater than 4 mm) in the antropyloric region, elongation of the antropyloric canal, persistent spasm, and delayed gastric emptying. Two of the infants had slight thickening of the pyloric muscle. Gastrointestinal series or endoscopy demonstrated thickened gastric mucosa and a deformed gastric antrum in all infants, as well as actual ulceration in five. 相似文献