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排序方式: 共有410条查询结果,搜索用时 15 毫秒
101.
Reduced tocopherol content of B cells from patients with chronic lymphocytic leukemia 总被引:1,自引:0,他引:1
The tocopherol content of lymphocytes, erythrocytes, and plasma from patients with chronic lymphocytic leukemia (CLL), hairy cell leukemia (HCL), and normal subjects was measured by a sensitive high performance liquid chromatographic method. Lymphocytes from patients with CLL had lower values of tocopherol (1.7 +/- 1.0 micrograms/10(9) cells) than lymphocytes from normal subjects (3.8 +/- 0.7 micrograms/10(9) cells). Mononuclear cells from patients with HCL had an increased tocopherol content of 6.2 +/- 1.0 micrograms/10(9) cells. Subfractionation of the lymphocytes from patients with CLL into T- and B-cell subgroups showed that the tocopherol content of T cells was the same as in normal subjects (4.1 +/- 0.5 micrograms/10(9) cells versus 3.5 +/- 1.2), but that the tocopherol content of the B cells was markedly reduced compared to normals (2.6 +/- 1.0 versus 6.0 +/- 1.3). 相似文献
102.
103.
LF Yap D Lee ANM Khairuddin MF Pairan B Puspita CH Siar IC Paterson 《Oral diseases》2015,21(7):850-857
NOTCH signalling can exert oncogenic or tumour suppressive effects in both solid and haematological malignancies. Similar to T‐cell acute lymphoblastic leukaemia (T‐ALL), early studies suggested a pro‐tumorigenic role of NOTCH in head and neck squamous cell carcinoma (HNSCC), mainly based on the increased expression levels of the genes within the pathway. Recently, data from exome sequencing analyses unexpectedly pointed to a tumour suppressor role for NOTCH in HNSCC by identifying loss‐of‐function mutations in the NOTCH1 gene in a significant proportion of patients. These data have questioned the accepted role of NOTCH in HNSCC and the possible rationale of targeting NOTCH in this disease. This review summarises the current information on NOTCH signalling in HNSCC and discusses how this pathway can apparently exert opposing effects within the same disease. 相似文献
104.
Background
Imprisonment may lead to the development of mental illness, especially depression. This study examines the clinical and sociodemographic profiles of imprisoned women, identifies indicative signs of depression, and relates these indicators to other variables. 相似文献105.
Cystatin C and carotid intima-media thickness in asymptomatic adults: the Multi-Ethnic Study of Atherosclerosis (MESA) 总被引:1,自引:0,他引:1
AL Bui R Katz B Kestenbaum IH de Boer LF Fried JF Polak BA Wasserman MJ Sarnak D Siscovick MG Shlipak 《American journal of kidney diseases》2009,53(3):389-398
BACKGROUND: Persons with early kidney disease have an increased risk of cardiovascular events and mortality, but the importance of accelerated atherosclerosis in promoting these outcomes is unclear. We therefore explored whether serum cystatin C level is associated with carotid intima-media thickness (IMT) in ambulatory adults without clinical heart disease. STUDY DESIGN: Cross-sectional study. SETTING & PARTICIPANTS: We evaluated 6,557 ethnically diverse persons free of clinical cardiovascular disease aged 45 to 84 years at the baseline visit of the Multi-Ethnic Study of Atherosclerosis. PREDICTORS: Kidney function was estimated by using 2 methods: serum cystatin C level and estimated glomerular filtration rate, based on creatinine and cystatin C levels. OUTCOMES & MEASUREMENTS: Study outcomes were internal and common carotid IMT, measured by using high-resolution B-mode ultrasound. Multivariate linear and logistic regressions were used to evaluate the independent association of kidney function with carotid IMT. RESULTS: In unadjusted linear analysis, each SD (0.23 mg/L) greater cystatin C level was associated with 0.091-mm greater internal carotid IMT (P < 0.001), but this association was diminished by 70% after adjustment for age, sex, and race/ethnicity (0.027 mm; P < 0.001) and was no longer significant after adjustment for cardiovascular risk factors (0.005 mm; P = 0.5). Similarly, the strong unadjusted associations of cystatin C level with common carotid IMT disappeared after adjustment. Chronic kidney disease, defined by using either creatinine level or cystatin C-based estimated glomerular filtration rate less than 60 mL/min/1.73 m(2), had no independent association with internal and common carotid IMT. LIMITATIONS: There were few participants with severe kidney disease. CONCLUSIONS: Cystatin C level had no independent association with carotid IMT in a population free of clinical heart disease. This observation suggests that accelerated atherosclerosis is unlikely to be the primary mechanism explaining the independent association of cystatin C level with cardiovascular risk. 相似文献
106.
Yuka Asai David Martino Thomas Eiwegger Kari Nadeau Gerard H. Koppelman Ann E. Clarke Young-Ae Lee Edmond S. Chan Elinor Simons Catherine Laprise Bruce Mazer Ingo Marenholz Diana Royce Susan J. Elliott Christine Hampson Jennifer Gerdts Aida Eslami Lianne Soller Jennie Hui Meghan Azad Andrew Sandford Denise Daley 《Allergy》2020,75(9):2383-2387
107.
目的:建立即刻种植动物模型,观察生物玻璃和生物胶原膜在即刻种植中引导骨组织再生、促进骨愈合效果.
方法:实验方法:取成年家犬12只,随机编号后分为4个组,在全麻下分别拔除双侧下颌第一双尖牙,制备近中拔牙窝并即刻植入种植体.前3个组分别应用生物玻璃填塞种植体与拔牙窝骨壁之间的间隙,或在种植床上方覆盖生物胶原膜,并尝试两种方法的联合应用,空白组不采用特殊处理.②观察指标:术后观察记录种植床愈合情况.术后4,8,12周分批处死动物并取其下颌骨标本,采用大体观察、X射线、普通光镜组织学方法和扫描电镜方法观察其在种植床中引起的骨组织再生变化过程和骨结合率,统计比较各种方法的成功率.
结果:①即刻种植成功率:总体成功率为95.8%,其中应用生物玻璃填塞种植体周围间隙可以诱导骨组织再生,其成功率均为100%,在种植床上方覆盖生物胶原膜者成功率为91.7%.②诱导骨组织再生作用:单用生物玻璃或两种方法联合应用诱导骨再生效果均较快,8周时表现骨质沉积量明显较多,其成骨呈多中心性,12周时可以诱导再生成熟的骨组织,并使种植体达到骨结合;应用生物胶原膜成骨呈向心性,成骨速度稍慢,12周时可以引导再生成熟的骨组织,并使种植体达到骨结合;空白组12周时在种植体的上部仍有较大部分软组织存在.
结论:在即刻种植中应用生物玻璃和生物胶原膜均可以诱导骨组织再生,促进骨愈合,获得较高的种植成功率;两者联合应用的成骨效果较单独应用生物胶原膜好. 相似文献
108.
109.
Xu M; Schut HA; Bjeldanes LF; Williams DE; Bailey GS; Dashwood RH 《Carcinogenesis》1997,18(11):2149-2153
Indole-3-carbinol (I3C) inhibits the formation of colonic aberrant crypt
foci and DNA adducts in rats given heterocyclic amine colon carcinogens,
such as 2-amino-3-methylimidazo[4,5-f]quinoline (IQ). Mechanism studies
indicate that I3C induces cytochromes P4501A1 and 1A2 (CYP1A1 and CYP1A2),
isozymes that respectively metabolize IQ via ring hydroxylation or activate
the carcinogen by N-hydroxylation. The present study examined the
dose-response for induction of CYP1A1 versus CYP1A2 by I3C, and compared
the profiles of induction with the dose- response for inhibition of IQ-DNA
adducts in the colon of the F344 rat. Dietary equivalent doses of I3C in
the range 100-1000 p.p.m. increased in a dose-related manner both
ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase
(MROD) activities in the liver and colonic mucosa, and Western blots showed
a corresponding induction of CYP1A1 and CYP1A2 proteins. However, dietary
equivalent doses of I3C in the range 10-25 p.p.m. (i) reduced hepatic EROD
and MROD activities and CYP1A protein levels compared with controls, (ii)
increased the ratio of CYP1A2 versus CYP1A1, and (iii) activated IQ to a
more potent mutagen when liver microsomes from rats given I3C were used for
metabolic activation in the Salmonella assay. Rats given a single oral dose
of I3C shortly before administering IQ (5 mg/kg body wt, p.o.) exhibited
dose-related inhibition of colonic IQ-DNA adducts in the range 25-100
p.p.m. I3C, reaching 95% inhibition at doses > or = 100 p.p.m. I3C, but
IQ-DNA adducts were elevated slightly at the lowest I3C dose as compared
with the controls. The possible significance of the low versus high dose
effects of I3C are discussed in the context of human dietary exposures to
I3C and the reported chemopreventive mechanisms of I3C in vivo.
相似文献
110.
Deletion/insertion mutation that causes biotinidase deficiency may result from the formation of a quasipalindromic structure 总被引:2,自引:0,他引:2
Pomponio RJ; Narasimhan V; Reynolds TR; Buck GA; Povirk LF; Wolf B 《Human molecular genetics》1996,5(10):1657-1661
Biotinidase is responsible for recycling the vitamin biotin from biocytin
that is formed after the proteolytic degradation of the biotin- dependent
carboxylases. We have identified a deletion/insertion mutation within exon
D of the human biotinidase gene in a child with biotinidase deficiency. The
mutation causes a frame shift and premature termination which are predicted
to result in a truncated protein. We propose that the mutation occurred
during DNA replication by either of two mechanisms. Both mechanisms involve
formation of a quasipalindromic hairpin loop in the template and
dissociation of DNA polymerase alpha. This mutation supports the formation
of palindromic structures as a possible cause of deletions in eukaryotes,
and supports the proposal, derived from in vitro studies, that polymerase
alpha may preferentially arrest or dissociate at specific template
sequences.
相似文献