全文获取类型
收费全文 | 859篇 |
免费 | 71篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 20篇 |
妇产科学 | 20篇 |
基础医学 | 117篇 |
口腔科学 | 36篇 |
临床医学 | 77篇 |
内科学 | 227篇 |
皮肤病学 | 57篇 |
神经病学 | 69篇 |
特种医学 | 11篇 |
外科学 | 50篇 |
综合类 | 9篇 |
预防医学 | 44篇 |
眼科学 | 3篇 |
药学 | 80篇 |
中国医学 | 1篇 |
肿瘤学 | 107篇 |
出版年
2023年 | 7篇 |
2022年 | 11篇 |
2021年 | 22篇 |
2020年 | 12篇 |
2019年 | 24篇 |
2018年 | 25篇 |
2017年 | 13篇 |
2016年 | 15篇 |
2015年 | 18篇 |
2014年 | 17篇 |
2013年 | 25篇 |
2012年 | 64篇 |
2011年 | 53篇 |
2010年 | 30篇 |
2009年 | 24篇 |
2008年 | 45篇 |
2007年 | 56篇 |
2006年 | 41篇 |
2005年 | 28篇 |
2004年 | 36篇 |
2003年 | 29篇 |
2002年 | 41篇 |
2001年 | 22篇 |
2000年 | 12篇 |
1999年 | 21篇 |
1998年 | 5篇 |
1997年 | 6篇 |
1996年 | 6篇 |
1995年 | 14篇 |
1994年 | 7篇 |
1993年 | 7篇 |
1992年 | 21篇 |
1991年 | 14篇 |
1990年 | 10篇 |
1989年 | 20篇 |
1988年 | 16篇 |
1987年 | 10篇 |
1986年 | 12篇 |
1985年 | 12篇 |
1984年 | 10篇 |
1983年 | 5篇 |
1981年 | 4篇 |
1979年 | 7篇 |
1977年 | 6篇 |
1975年 | 5篇 |
1974年 | 3篇 |
1971年 | 5篇 |
1970年 | 4篇 |
1969年 | 4篇 |
1966年 | 4篇 |
排序方式: 共有935条查询结果,搜索用时 8 毫秒
1.
Maria Cristina Locatelli Lucilla Tedeschi Maurizia Clerici Antonella Romanelli Adelaide D'Antona Roberto Labianca Gino Luporini 《Supportive care in cancer》1996,4(3):218-219
We have reviewed the incidence of cisplatin-induced anaemia in patients affected with solid tumours treated with at least three courses of first-line cisplatincontaining regimens. In our experience, a low percentage (5%) of patients required transfusions of red blood cells. We think it is of the utmost importance to adopt uniform criteria in monitoring and treatment of patients at risk of developing cisplatin anaemia and to identify subsets of patients to eventually treat with erythropoietin. 相似文献
2.
A few constitutive cytochrome P-450 isozymes in male rat liver microsomes catalyzed the metabolism of benzo[a]pyrene (BP) in cumene hydroperoxide (CHP)-dependent reactions, which produced predominantly 3-hydroxyBP and BP quinones. This process varied with the concentration of CHP. At 0.05 mM CHP, 3-hydroxyBP was the major metabolite. An increase in CHP concentration reduced 3-hydroxyBP formation but increased the level of BP quinones. This change in metabolic profile was reversed by preincubation with pyrene. Pyrene selectively inhibited quinone formation and enhanced 3-hydroxyBP formation. Naphthalene, phenanthrene and benz[a]anthracene nonspecifically inhibited total metabolism. BP binding to microsomal protein correlated with quinone formation, suggesting a common precursor reactive intermediate. BP metabolism by female rat liver microsomes also depended on CHP concentration but was much less effective than that in the male. With females, quinones were the major metabolites at all CHP concentrations, and their formation was again modulated by pyrene. These data indicate that two distinct binding sites are responsible for the formation of 3-hydroxyBP and BP quinones. 相似文献
3.
G F Ferraccioli F Cavalieri W Troise Rioda P Bonelli D Franchini G Ugolotti 《Scandinavian journal of rheumatology》1991,20(5):314-318
We studied P-III-P levels along with several acute phase reactants, Beta-2-microglobulin and autoantibody synthesis in 52 rheumatoid patients. No relationship arose between P-III-P levels and immunological parameters nor with acute phase reactants. We observed a highly significant difference between P-III-P levels in patients with knee and/or hip involvement with respect to those with only polyarthritis of small joints (86.1 +/- 21.5 vs 61.2 +/- 19.1 ng/ml; p less than 0.001). In 24 consecutive patients we also observed a significant correlation (p less than 0.02) between P-III-P levels and AIMS score. We conclude that P-III-P levels are mainly related to the synovial inflammation of major joints and as such P-III-P might represent the biochemical marker of the synovial mass in rheumatoid arthritis. 相似文献
4.
Do weekly and fast-rotating shiftwork schedules differentially affect duration and quality of sleep?
F. M. Fischer Antonio Castro Bruni Adelaide Berwerth Claudia Roberta Castro Moreno Rosaneli Lima Fernandez Claudia Riviello 《International archives of occupational and environmental health》1997,69(5):354-360
Characteristics of shiftwork schedules can have distinct impacts on workers’ sleep. This report presents comparisons of the
effects of two different shiftwork schedules on duration and quality of the main sleep episodes in comparable worker populations
at two different petrochemical plants. No significant differences were found for sleep duration in comparing the two plants.
However, within each plant’s shift cycles, morning and night shifts showed shorter sleep durations than all other workdays
and days off. Quality of sleep was perceived as lowest for night shifts of both plant schedules, and of lesser quality for
weekly than for fast-rotating shifts. These results support recommendations for reducing the number of consecutive nights
of shiftwork. However, before recommending any optimal shift schedule, interactions of sleep duration and quality with shift
schedules need much further evaluation.
Received: 18 December 1995/Accepted: 18 July 1996 相似文献
5.
6.
7.
Tancredi M Sensi E Cipollini G Aretini P Lombardi G Di Cristofano C Presciuttini S Bevilacqua G Caligo MA 《European journal of human genetics : EJHG》2004,12(9):775-777
Germ-line mutations in the BRCA1 gene cause hereditary predisposition to breast and ovarian cancer. BRCA1 and BRCA2 mutations account for about 40% of high-risk families. Mutation-screening methods generally focus on genomic DNA and are usually PCR based; they enable the detection of sequence alterations such as point mutations and small deletions and insertions. However, they do not allow the detection of partial or entire exon(s) loss, because the presence of the homologous allele results in a positive PCR signal, giving rise to a false-negative result. Identification of unusual haplotypes in patient samples by an expectation maximization algorithm has recently been suggested as a method for identifying hemizygous regions caused by large intragenic deletions. Using a similar approach, we identified a novel BRCA1 genomic rearrangement in a breast/ovarian cancer family negative at the first mutation screening; we detected a deletion encompassing exons 14-19, probably due to replication slippage between Alu sequences. 相似文献
8.
Biochemical characterization of simian foamy virus type I 总被引:2,自引:0,他引:2
Cavalieri F. Rhodes-Feuillette A. Benzair A. B. Emanoïl-Ravicovitch R. Peries J. 《Archives of virology》1981,68(3-4):197-202
Summary Simian syncitium-forming (foamy) virus type I (SFV1) was characterized biochemically. RNA was extracted from purified virus either with 0.1 per cent SDS or by the standard phenol-chloroform method. By both techniques a main component of 65–70S was found. Denaturation of the 65–70S RNA by heat resulted in a shift of the sedimentation coefficient mainly to a 30–35S component. Electrophoresis on a composite polyacrylamide gel demonstrated the existence of three minor RNA's: 8S, 5S and 4S respectively. PAGE-SDS analysis of disrupted purified virions enabled the separate migration of five viral proteins and the identification of two main proteins: a 30 kd polypeptide and a 70 kd polypeptide.With 4 Figures 相似文献
9.
10.
do Valle Matta MA Sales Alviano D dos Santos Silva Couceiro JN Nazareth M Meirelles L Sales Alviano C Angluster J 《Parasitology research》1999,85(4):293-299
The cell-surface expression of sialoglycoconjugate structures in wild-type Crithidia fasciculata and its TFRR1 drug-resistant mutant was analyzed with the aid of an influenza C virus strain, lectin, enzymatic treatment, and flow cytofluorimetry
analysis probed with fluorescein isothiocyanate-labeled (FITC) lectins. 9-O-Acetyl-N-acetyl neuraminic acid (Neu5,9Ac2) structures mediate influenza C virus cell-binding. The SAα2,3Gal and SAα2,6Gal sequences are specifically recognized by
Maackia amurensis (MAA) and Sambucus nigra (SNA) lectins, respectively. On the basis of these param- eters the TFRR1 mutant strain of C. fasciculata was found to contain exposed sialoglycoconjugates bearing Neu5,9Ac2 surface structures. After the removal of sialic acid residues by neuraminidase activity the marked increases in PNA (peanut
agglutinin)-mediated agglutinating activity showed that those acidic units on C. fasciculata cells were glycosidically linked to d-galactose. The bond involves SAα2,6Gal and SAα2,3Gal linkages as suggested by the use of FITC-SNA and FITC-MAA lectins, respectively.
Both SAα2,3Gal and SAα2,6Gal sequences were preferentially expressed by the TFRR1 mutant. The SAα2,6 linkage markedly predominated. In the TFRR1 mutant, but not in wild-type cells, two distinct populations of cells were distinguished by reactivity with FITC-SNA, one
of which was enriched with surface SAα2,6Gal sequences. These diverse findings suggest that sialoglycoconjugate structures
present on the flagellate surface may be associated with mutation and the cell growth cycle in C. fasciculata.
Received: 17 September 1998 / Accepted: 22 October 1998 相似文献