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排序方式: 共有674条查询结果,搜索用时 15 毫秒
11.
Identification of two mutations in a compound heterozygous child with dihydrolipoamide dehydrogenase deficiency 总被引:1,自引:0,他引:1
Hong YS; Kerr DS; Craigen WJ; Tan J; Pan Y; Lusk M; Patel MS 《Human molecular genetics》1996,5(12):1925-1930
An infant girl with elevated blood lactate, pyruvate, and plasma
branched-chain amino acids was diagnosed with dihydrolipoamide
dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4)
deficiency. Activities of the pyruvate dehydrogenase complex and E3 from
patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in
cultured skin fibroblasts, respectively. Western blot analysis demonstrated
that the amount of E3 protein in fibroblasts from the patient and her
father was about half of controls, while Northern blot analysis showed
normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs
from the patient revealed two mutations in separate alleles. One is a
single base insertion of an extra adenine in the last codon of the leader
peptide sequence (TAC-->TAAC) leading to a nonsense mutation which
results in the premature termination of the precursor E3 polypeptide
(Y35X). The other is a missense mutation due to substitution of guanine for
adenine, causing an Arg-->Gly substitution at amino acid 460 of the
mature protein (R460G) which triggers the loss of E3 activity probably by
structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the
parents demonstrated that the nonsense mutation was inherited from the
father and the missense mutation was inherited from the mother.
相似文献
12.
Michael WJ Hii Robert N Gibson Anthony G Speer Neil A Collier Noel Sherson Cate Jardine 《Journal of Medical Imaging and Radiation Oncology》2003,47(4):393-403
We reviewed the results of percutaneous intervention of hilar biliary malignancy over a 10‐year period at a single institution: the Royal Melbourne Hospital. Ninety‐nine patients (100 treated in total) were included. Information was retrieved by retrospective examination of patient notes and radiology, combined with interviews with family and relevant physicians. Sixty‐nine patients were treated with insertion of semipermanent stents, 19 had external drain tubes, and 25 received percutaneous access for Iridium brachytherapy. Adequate drainage was achieved in 87% of the patients stented, and percutaneous access was successful in 96% of patients planned for brachytherapy. Of those patients undergoing endoprosthesis insertion, early complications occurred in 39% and late complications in 23%. Average survival for the entire patient population was 227.3 days, with a median of 167 days. Longer survival times (213 vs 142 days) and lower complication rates (44 vs 64%) are observed with metal stents in comparison with plastic stents. Percutaneous intervention is an important treatment option in hilar biliary malignancy, particularly in patients unfit for surgery. Reasonable survival with good palliation is the most common outcome, and most patients do not require further intervention. 相似文献
13.
14.
Isolation and characterization of propagable cell lines (HUNC) from the androgen-sensitive Dunning R3327H rat prostatic adenocarcinoma 总被引:1,自引:0,他引:1
Presnell SC; Borchert KM; Glover WJ; Gregory CW; Mohler JL; Smith GJ 《Carcinogenesis》1998,19(4):585-590
The Dunning H rat prostate tumor (R3327H) is a widely used experimental
model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been
characterized as androgen-sensitive, androgen-receptor (AR) positive,
prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To
date, the tumor has been maintained by serial passage in vivo because of
the lack of an in vitro cell line that retains the characteristics of the
in vivo tumor. The objective of the present study was to establish a
propagable cell line from R3327H adenocarcinoma that maintained androgen
sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in
vivo R3327H tumor was dissociated with collagenase and placed into
Richter's improved media (with supplements). A cytokeratin-positive
epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line
(HUNC-S) were generated from the primary culture, subcultured continuously
for >300 days, and passaged >50 times. Survival of the HUNC-E cell
line in vitro depended on several media supplements, including
nicotinamide, insulin, transferrin, selenium and epidermal growth factor
(EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the
culture period, as confirmed by immunocytochemistry and Western blot
analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT)
to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent
growth and PSA production, which demonstrated the androgen-sensitive nature
of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1
ratio and introduced subcutaneously into syngeneic male hosts, tumors
formed in 2/3 animals with an average latency of 7 months. RT-PCR and
immunocytochemical characterization of the HUNC cell lines revealed that
the cells expressed several growth factors and their cognate receptors,
including HGF, TGF-alpha and the TGF-betas, indicating the establishment of
potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S
CaP cell lines, which retain the characteristics of the epithelial and
stromal components of the in vivo R3327H tumor, will allow a more thorough
and informative molecular and biological analysis of prostatic
adenocarcinoma.
相似文献
15.
In order to enhance the immune efficacy of DNA vaccination, experiments were conducted to investigate the regulating effects of Bacillus Calmette-Guerin (BCG)-DNA as an adjuvant on immune responses of mice against foot-and-mouth disease (FMD), Aujeszky's disease (AID) and classical swine fever (CSF). BCG-DNA was purified from BCG by ion-exchange chromatography. Three DNA vaccines (pVSG, pVgD and pVE2) against the respective infection were constructed, and BCGDNA was coimmunized to mice by muscle injection. The results showed that titres of specific immunoglobulin (Ig)G to the vaccines mounted remarkably in the sera of the adjuvant covaccinated mice (P〈0.01). Antibody isotype IgG2a and IgG1 also increased, respectively, in mice coimmunized with BCG-DNA compared with those of the control groups (P〈0.01). Cellular immune cytokine interferon-gamma and cytotoxic T lymphocytes were detected in coimmunized BCG-DNA groups (P〈0. 05). Whereas interleukin-4, humoral immune cytokine, was not significant (P〉 0. 05). These results suggest that codelivery of BCG-DNA with DNA vaccines against FMD, AjD and CSF can enhance the induction of antigen-specific, especially, cell-mediated immunity. 相似文献
16.
Joline W.J. Beulens Yvonne T. van der Schouw Karel G.M. Moons Hendriek C. Boshuizen Daphne L. van der A Rolf H.H. Groenwold 《Annals of epidemiology》2013,23(4):193-197
PurposeModerate alcohol consumption is associated with a reduced type 2 diabetes risk, but the biomarkers that explain this relation are unknown. The most commonly used method to estimate the proportion explained by a biomarker is the difference method. However, influence of alcohol–biomarker interaction on its results is unclear. G-estimation method is proposed to accurately assess proportion explained, but how this method compares with the difference method is unknown.MethodsIn a case–cohort study of 2498 controls and 919 incident diabetes cases, we estimated the proportion explained by different biomarkers on the relation between alcohol consumption and diabetes using the difference method and sequential G-estimation method.ResultsUsing the difference method, high-density lipoprotein cholesterol explained the relation between alcohol and diabetes by 78% (95% confidence interval [CI], 41–243), whereas high-sensitivity C-reactive protein (?7.5%; ?36.4 to 1.8) or blood pressure (?6.9; ?26.3 to ?0.6) did not explain the relation. Interaction between alcohol and liver enzymes led to bias in proportion explained with different outcomes for different levels of liver enzymes. G-estimation method showed comparable results, but proportions explained were lower.ConclusionsThe relation between alcohol consumption and diabetes may be largely explained by increased high-density lipoprotein cholesterol but not by other biomarkers. Ignoring exposure–mediator interactions may result in bias. The difference and G-estimation methods provide similar results. 相似文献
17.
Joline W. J. Beulens Heidi P. Fransen Ellen A. Struijk Jolanda M. A. Boer G. Ardine de Wit N. Charlotte Onland-Moret Jeljer Hoekstra H. Bas Bueno-de-Mesquita Anne M. May 《European journal of epidemiology》2017,32(4):317-326
The relation of alcohol consumption with disease burden remains debated partly due to opposite associations with cardiovascular disease (CVD) and cancer. The relation of alcohol consumption with disease burden expressed in disability-adjusted life years (DALYs) summarizes opposing associations of alcohol consumption on chronic diseases. This study aimed to investigate the association of alcohol consumption with chronic disease burden expressed in DALYs based on individual-participant data. The study was a prospective study among 33,066 men and women from the EPIC-NL cohort. At baseline, alcohol consumption was assessed with a validated food-frequency questionnaire. Participants were followed for occurrence of and mortality from chronic diseases and DALYs were calculated. After 12.4 years follow-up, 6647 disease incidences and 1482 deaths were documented, resulting in 68,225 healthy years of life lost (6225 DALYs). Moderate drinkers (women 5–14.9 g/day, men 5–29.9 g/day) had a lower chronic disease burden (mean DALYs ?0.27; 95% CI ?0.43; ?0.11) than light drinkers (0–4.9 g/day), driven by a lower disease burden due to CVD (?0.18: ?0.29; ?0.06) but not cancer (?0.05: ?0.16; 0.06). The associations were most pronounced among older participants (≥50 years; ?0.32; ?0.53; ?0.10) and not observed among younger women (?0.08; ?0.43; 0.35), albeit non-significant (pinteraction > 0.14). Substantial drinking (women 15–29.9 g/day, men 30–59.9 g/day) compared to light drinking was not associated with chronic disease burden. Our results show that moderate compared to light alcohol consumption was associated with living approximately 3 months longer in good health. These results were mainly observed among older participants and not seen among younger women. 相似文献
18.
Clinical features and serum antinuclear antibodies in 230 Danish patients with systemic sclerosis 总被引:5,自引:2,他引:5
Jacobsen S; Halberg P; Ullman S; Van Venrooij WJ; Hoier-Madsen M; Wiik A; Petersen J 《Rheumatology (Oxford, England)》1998,37(1):39-45
The objective was to investigate the relationship between the presence of
different types of antinuclear antibodies (ANA) in patients with systemic
sclerosis (SSc) and the presence of clinical features. Sera from 230
patients with SSc were tested for the presence of ANA, including
anticentromere antibodies (ab), antitopoisomerase I ab, anti- U1 RNP ab and
antinucleolar ab, including anti-Th RNP, anti-U3 RNP and anti-U17 RNP.
Clinical features were registered prospectively in a clinical database.
Eighty-two per cent of the patients were women. The median age was 58 yr
(45-67, quartiles) and median age at disease onset was 44 (30-55) yr. ANA
were found in 86% of the patients (anticentromere: 34%; antitopoisomerase
I: 14%; anti-U1 RNP: 6.5%; antinucleolar total: 16%; anti-Th RNP: 2.2%;
anti-U3 RNP: 3.5%; anti- U17 RNP: 0%). Anticentromere ab were found to be
related to a high prevalence of calcinosis, telangiectasia, digital ulcers,
acrosclerosis, primary biliary cirrhosis, isolated reduction of pulmonary
diffusing capacity, and a low prevalence of radiological evidence of
pulmonary fibrosis. Antitopoisomerase I ab were associated with a high
prevalence of digital joint deformity, distal osteolysis, radiological
signs of pulmonary fibrosis, a low prevalence of calcinosis and late onset
of disease. Anti-U1 RNP ab were related to a high prevalence of arthritis
and myositis, a low prevalence of calcinosis, and early disease onset. The
presence of antinucleolar ab, including anti-U3 RNP and anti-Th RNP, was
not significantly related to any particular clinical features in this
study; possibly due to the small number of patients with these ab. The
presence of anticentromere, antitopoisomerase I and anti-U1 RNP ab in the
serum was also found to have previously described clinical correlations in
a group of Danish SSc patients.
相似文献
19.
取样胶囊主要是吸取人体消化道内的消化液进行研究,本文以胃液为例,对取样胶囊吸取消化液进行探讨,分析在取样胶囊的研究中选取何种吸附材料最合适.首先对胃液成分进行分析,然后配置模拟胃液,选取六种不同吸附材料进行了吸附实验,并按实验结果绘制了不同的吸附曲线.由实验结果,对各种材料的吸附量、吸附稳定性和可靠性等进行了对比分析,同时还对取样机构模型设计的简单化因素进行分析.最后得出结论,认为德制胶棉在各个因素上都有明显的优势,适宜作为取样胶囊中的吸附材料. 相似文献
20.
Jacqueline AM Smith DL Patil OT Daniels Y-S Ding J-D Gallezot S Henry KHS Kim S Kshirsagar WJ Martin GP Obedencio E Stangeland PR Tsuruda W Williams RE Carson ST Patil 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2015,18(2)