全文获取类型
收费全文 | 769篇 |
免费 | 32篇 |
国内免费 | 67篇 |
专业分类
耳鼻咽喉 | 67篇 |
儿科学 | 29篇 |
妇产科学 | 7篇 |
基础医学 | 197篇 |
口腔科学 | 9篇 |
临床医学 | 89篇 |
内科学 | 94篇 |
皮肤病学 | 13篇 |
神经病学 | 22篇 |
特种医学 | 138篇 |
外科学 | 25篇 |
综合类 | 24篇 |
预防医学 | 37篇 |
眼科学 | 2篇 |
药学 | 89篇 |
中国医学 | 1篇 |
肿瘤学 | 25篇 |
出版年
2022年 | 3篇 |
2021年 | 9篇 |
2020年 | 7篇 |
2019年 | 6篇 |
2018年 | 8篇 |
2017年 | 8篇 |
2016年 | 16篇 |
2015年 | 15篇 |
2014年 | 15篇 |
2013年 | 24篇 |
2012年 | 26篇 |
2011年 | 24篇 |
2010年 | 34篇 |
2009年 | 43篇 |
2008年 | 35篇 |
2007年 | 78篇 |
2006年 | 28篇 |
2005年 | 28篇 |
2004年 | 12篇 |
2003年 | 20篇 |
2002年 | 16篇 |
2001年 | 17篇 |
2000年 | 19篇 |
1999年 | 12篇 |
1998年 | 26篇 |
1997年 | 35篇 |
1996年 | 26篇 |
1995年 | 25篇 |
1994年 | 21篇 |
1993年 | 19篇 |
1992年 | 10篇 |
1991年 | 10篇 |
1990年 | 14篇 |
1989年 | 17篇 |
1988年 | 22篇 |
1987年 | 13篇 |
1986年 | 10篇 |
1985年 | 19篇 |
1984年 | 6篇 |
1983年 | 7篇 |
1982年 | 13篇 |
1981年 | 6篇 |
1980年 | 13篇 |
1979年 | 7篇 |
1978年 | 7篇 |
1977年 | 9篇 |
1976年 | 7篇 |
1975年 | 9篇 |
1974年 | 3篇 |
1973年 | 4篇 |
排序方式: 共有868条查询结果,搜索用时 156 毫秒
11.
12.
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
13.
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
14.
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)
Background:
Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.Methods:
We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.Results:
TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.Conclusions:
These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation. 相似文献15.
Dal Canto Elisa Remmelzwaal Sharon van Ballegooijen Adriana Johanne Handoko M. Louis Heymans Stephane van Empel Vanessa Paulus Walter J. Nijpels Giel Elders Petra Beulens Joline WJ 《Heart failure reviews》2022,27(1):207-218
Heart Failure Reviews - This study aimed to evaluate the diagnostic performance of echocardiographic markers of heart failure with preserved ejection fraction (HFpEF) and left ventricular diastolic... 相似文献
16.
Connor WJ Bevington Ju-Chieh Cheng Ivan S Klyuzhin Mariya V Cherkasova Catharine A Winstanley Vesna Sossi 《Journal of cerebral blood flow and metabolism》2021,41(1):116
Current methods using a single PET scan to detect voxel-level transient dopamine release—using F-test (significance) and cluster size thresholding—have limited detection sensitivity for clusters of release small in size and/or having low release levels. Specifically, simulations show that voxels with release near the peripheries of such clusters are often rejected—becoming false negatives and ultimately distorting the F-distribution of rejected voxels. We suggest a Monte Carlo method that incorporates these two observations into a cost function, allowing erroneously rejected voxels to be accepted under specified criteria. In simulations, the proposed method improves detection sensitivity by up to 50% while preserving the cluster size threshold, or up to 180% when optimizing for sensitivity. A further parametric-based voxelwise thresholding is then suggested to better estimate the release dynamics in detected clusters. We apply the Monte Carlo method to a pilot scan from a human gambling study, where additional parametrically unique clusters are detected as compared to the current best methods—results consistent with our simulations. 相似文献
17.
Tom De Beule T Boulanger S Heye WJ van Rooij WH van Zwam L Stockx 《Interventional neuroradiology》2021,27(1):51
Background and purposeFlow diverters are increasingly used to treat intracranial aneurysms. We report the safety and efficacy of the p64 flow diverter, a resheathable and detachable device for intracranial aneurysms.Materials and methodsWe retrospectively reviewed 108 patients with 109 aneurysms treated with the p64 between March 2014 and July 2019. There were 87 women and 21 men, mean age 57 years. Of 109 aneurysms, 74 were discovered incidentally, 12 were symptomatic, 18 were previously treated, and five were ruptured dissection aneurysms. A total of 10 aneurysms were located in the posterior circulation. The mean aneurysm or remnant size was 8.1 mm.ResultsHemorrhage by perforation with the distal guidewire occurred in two patients with permanent neurological deficits in one. In one patient, acute in-stent occlusion caused infarction with a permanent deficit. Permanent morbidity was 1.9% (2 of 108, 95%CI 0.1–6.9%); there was no mortality. During follow-up, three in-stent occlusions occurred, all asymptomatic. There were no delayed hemorrhagic complications. At six months, 77 of 96 aneurysms (80.2%) were completely occluded, and at last follow-up, this increased to 93 of 96 aneurysms (96.9%). In-stent stenosis at any degree occurred in 11 patients, progressing to asymptomatic complete occlusion in one. In the other patients, stenosis resolved or improved at further follow-up.ConclusionThe p64 offers an effective and safe treatment option. Aneurysm occlusion rate was 97% at last follow-up, mostly achieved with a single device. There were no delayed hemorrhagic complications. Delayed in-stent stenosis infrequently progresses to occlusion but remains a matter of concern. 相似文献
18.
Purified populations of natural killer (NK) cells were obtained from mice with severe combined immune deficiency (SCID). SCID spleen cells were cultured and activated with recombinant human interleukin-2 (rhIL- 2) in vitro. The activated NK cells were then transferred with syngeneic BALB/c bone marrow cells (BMC) and rhIL-2 into lethally irradiated syngeneic recipients to determine their effect on long-term hematopoietic reconstitution. On analysis, the transfer of rhIL-2- activated NK cells along with BMC resulted in significant increases in splenic and BM hematopoietic progenitor cells when compared with those for mice not receiving NK cells. Histologic and flow cytometric analysis showed a marked increase in granulocytic and megakaryocytic lineage cells present in the spleens of the mice receiving activated NK cells. Analysis of the peripheral blood indicated that the transfer of activated NK cells with BMC also significantly improved platelet and total white blood cell counts, with increases in segmented neutrophils. Erythroid recovery was not affected. Finally, lethally irradiated mice receiving activated NK cells and rhIL-2 along with limiting numbers of syngeneic BMC showed a marked increase in survival rate. These results show that the use of populations enriched for activated NK cells after syngeneic BM transplantation (BMT) has a profound enhancing effect on engraftment primarily affecting megakaryocytic and granulocytic cell reconstitution. Therefore, the transfer of activated NK cells and rhIL- 2 may be of clinical use to promote hematopoietic reconstitution after BMT. 相似文献
19.
M.C. Berkhout E. Rijntjes L.H. el Bouazzaoui W.J. Fokkens R.W. Brimicombe H.G.M. Heijerman 《Journal of cystic fibrosis》2013,12(5):525-529
BackgroundRecently the influence of the upper airways (UAW) on the general health of a patient with Cystic Fibrosis (CF) has been acknowledged. Surprisingly the microbiology of the upper compartment of the airways receives barely any attention in the treatment of CF. The aim of the present study was to investigate the microbiology of the upper airways in adult patients with CF, to correlate these findings with cultures from the lower airways (LAW) and with clinical characteristics.MethodsIn this cross-sectional study bacteriological and clinical data were gathered from 104 adult patients with CF. UAW samples for culture were collected by nasal lavage and middle meatal swabs; LAW cultures were performed on expectorated sputum or cough swabs. Each patient performed the Rhinosinusitis Outcome Measure (RSOM-31).ResultsIn 72 patients (69.2%) UAW cultures yielded microorganisms other than normal nasal flora and in 50 patients (48.1%) Pseudomonas aeruginosa grew from the UAW cultures. Similarity between UAW and LAW cultures was determined in 50.0% of these 72 patients. In 3 patients P. aeruginosa was cultured from the UAW after successful eradication of P. aeruginosa from the LAW. P. aeruginosa in the UAW did not influence symptoms of sinonasal disease compared to other microorganisms.ConclusionsComparison of UAW and LAW cultures in adult patients with CF showed one or more concordant microorganism in 50.0% of the patients. P. aeruginosa was most frequently cultured from the UAW. P. aeruginosa can be cultured from the UAW after eradication therapy which may suggest persistence of P. aeruginosa in the UAW. We feel this is may be a motive to include the UAW in eradication therapy in Cystic Fibrosis. 相似文献
20.