全文获取类型
收费全文 | 1050篇 |
免费 | 54篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 23篇 |
儿科学 | 47篇 |
妇产科学 | 8篇 |
基础医学 | 154篇 |
口腔科学 | 1篇 |
临床医学 | 75篇 |
内科学 | 224篇 |
皮肤病学 | 17篇 |
神经病学 | 44篇 |
特种医学 | 22篇 |
外科学 | 139篇 |
综合类 | 45篇 |
预防医学 | 51篇 |
眼科学 | 9篇 |
药学 | 79篇 |
中国医学 | 3篇 |
肿瘤学 | 166篇 |
出版年
2023年 | 5篇 |
2022年 | 11篇 |
2021年 | 27篇 |
2020年 | 13篇 |
2019年 | 22篇 |
2018年 | 22篇 |
2017年 | 22篇 |
2016年 | 17篇 |
2015年 | 26篇 |
2014年 | 44篇 |
2013年 | 39篇 |
2012年 | 74篇 |
2011年 | 81篇 |
2010年 | 53篇 |
2009年 | 35篇 |
2008年 | 66篇 |
2007年 | 42篇 |
2006年 | 36篇 |
2005年 | 39篇 |
2004年 | 52篇 |
2003年 | 42篇 |
2002年 | 35篇 |
2001年 | 22篇 |
2000年 | 17篇 |
1999年 | 20篇 |
1997年 | 6篇 |
1992年 | 5篇 |
1990年 | 9篇 |
1989年 | 12篇 |
1988年 | 10篇 |
1987年 | 10篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1984年 | 6篇 |
1983年 | 7篇 |
1982年 | 6篇 |
1980年 | 11篇 |
1979年 | 10篇 |
1978年 | 7篇 |
1977年 | 5篇 |
1975年 | 7篇 |
1974年 | 9篇 |
1973年 | 10篇 |
1972年 | 7篇 |
1970年 | 13篇 |
1969年 | 8篇 |
1968年 | 7篇 |
1967年 | 8篇 |
1966年 | 4篇 |
1939年 | 4篇 |
排序方式: 共有1107条查询结果,搜索用时 31 毫秒
41.
42.
Shiv Kumar Sarin Ashish Kumar Yogesh Kumar Chawla Sanjay Saran Baijal Radha Krishna Dhiman Wasim Jafri Laurentius A Lesmana Debendranath Guha Mazumder Masao Omata Huma Qureshi Rizvi Moattar Raza Peush Sahni Puja Sakhuja Mohammad Salih Amal Santra Barjesh Chander Sharma Praveen Sharma Gamal Shiha Jose Sollano 《Hepatology International》2007,1(3):398-413
The Asian Pacific Association for the Study of the Liver (APASL) Working Party on Portal Hypertension has developed consensus
guidelines on the disease profile, diagnosis, and management of noncirrhotic portal fibrosis and idiopathic portal hypertension.
The consensus statements, prepared and deliberated at length by the experts in this field, were presented at the annual meeting
of the APASL at Kyoto in March 2007. This article includes the statements approved by the APASL along with brief backgrounds
of various aspects of the disease. 相似文献
43.
Incubation of platelet-rich plasma with 80 microM aspirin that resulted in the inhibition of both the secondary phase of ADP induced platelet aggregation and prostaglandin synthesis simultaneously stimulated the production of NO in platelets. Furthermore it was found that the treatment of platelet-rich plasma either with 80 microM ibuprofen or salicylic acid, like aspirin, which inhibited the secondary phase of platelet aggregation by ADP and prostaglandin synthesis, also stimulated the production of NO in the absence of added ADP. However the inhibition of prostaglandin synthesis by ibuprofen or salicylic acid, unlike aspirin, was transient in nature. Incubation of washed platelets with any of these three compounds also stimulated NO synthesis indicating that the effect of these compounds was not mediated through plasma proteins. The in vitro effect of aspirin on the increase of NO in platelets could also be demonstrated by in vivo exposure of platelets to the compound. It was concluded that either a temporary or a lasting inhibition of prostaglandin synthesis by these inhibitors resulted in the synthesis of NO in resting platelets. Since NO is a potent inhibitor of platelet aggregation the inhibition of platelet aggregation, by these compounds may not be the consequence of the inhibition of prostaglandin synthesis alone, but could also be related, at least partly, to the stimulated synthesis of NO by these inhibitors. 相似文献
44.
Isolation of cDNA clones coding for human tissue factor: primary structure of the protein and cDNA. 总被引:16,自引:3,他引:16
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
E K Spicer R Horton L Bloem R Bach K R Williams A Guha J Kraus T C Lin Y Nemerson W H Konigsberg 《Proceedings of the National Academy of Sciences of the United States of America》1987,84(15):5148-5152
Tissue factor is a membrane-bound procoagulant protein that activates the extrinsic pathway of blood coagulation in the presence of factor VII and calcium. lambda Phage containing the tissue factor gene were isolated from a human placental cDNA library. The amino acid sequence deduced from the nucleotide sequence of the cDNAs indicates that tissue factor is synthesized as a higher molecular weight precursor with a leader sequence of 32 amino acids, while the mature protein is a single polypeptide chain composed of 263 residues. The derived primary structure of tissue factor has been confirmed by comparison to protein and peptide sequence data. The sequence of the mature protein suggests that there are three distinct domains: extracellular, residues 1-219; hydrophobic, residues 220-242; and cytoplasmic, residues 243-263. Three potential N-linked carbohydrate attachment sites occur in the extracellular domain. The amino acid sequence of tissue factor shows no significant homology with the vitamin K-dependent serine proteases, coagulation cofactors, or any other protein in the National Biomedical Research Foundation sequence data bank (Washington, DC). 相似文献
45.
Uday?C?GhoshalEmail author Debashish?Guha Santu?Bandyopadhyay Chiranjib?Pal Srikanta?Chakraborty Ujjala?Ghoshal Tamal?K?Ghosh Bhaskar?B?Pal Prabir?K?Banerjee 《BMC gastroenterology》2002,2(1):6
Background
Helicobacter pylori (H. pylori) has been etiologically linked with primary gastric lymphoma (PGL) and gastric carcinoma (GC). There are a few reports of occurrence of both diseases in the same patient with H. pylori infection.Case presentation
We report a patient with PGL in whom the tumor regressed after surgical resection combined with eradication of H. pylori infection. However, he developed GC on follow up; this was temporally associated with recrudescence / re-infection of H. pylori. This is perhaps first report of such occurrence.Conclusions
Possible cause and effect relationship between H. pylori infection and both PGL and GC is discussed. This case also documents a unique problem in management of PGL in tropical countries where re-infection with H. pylori is supposed to be high.46.
Background
Subglottic stenosis (SGS) is the most common congenital and/or acquired laryngotracheal anomaly requiring tracheotomy in infants. We sought to determine factors associated with a greater likelihood of tracheotomy in symptomatic infants with SGS who underwent laryngotracheoplasty (LTP).Methods
Retrospective case series with chart review of patients undergoing single-stage LTP for SGS over a 10-year period (2001–2010) in a tertiary-care pediatric hospital.Results
Twenty-two children (15 boys, 7 girls), with a mean gestational age of 32.5 weeks, underwent LTP with and without interpositional grafting, at a median age of 89 days. Ten patients (43%) required postoperative tracheotomy. Of patients weighing < 2.5 kg, 7 of 8 eventually required tracheotomy, while none weighing > 5 kg needed tracheotomy (p = 0.003). The average length of stay for patients with a tracheotomy was 125 days, while those without tracheotomy required only 58 days (p = 0.011). The grade of SGS (p = 0.809), gender (p = 0.968), age at surgery (p = 0.178), and gestational age (p = 0.117) were not significantly associated with the need for tracheotomy. Weight at surgery was significantly correlated with the likelihood of needing tracheotomy (p = 0.003).Conclusions
Patients who weighed less than 2.5 kg at the time of LTP procedures were more likely to require a postoperative tracheotomy. Children who required tracheotomy had longer lengths of hospital stay. 相似文献47.
Lesley A. Mathews Griner Rajarshi Guha Paul Shinn Ryan M. Young Jonathan M. Keller Dongbo Liu Ian S. Goldlust Adam Yasgar Crystal McKnight Matthew B. Boxer Damien Y. Duveau Jian-Kang Jiang Sam Michael Tim Mierzwa Wenwei Huang Martin J. Walsh Bryan T. Mott Paresma Patel William Leister David J. Maloney Christopher A. Leclair Ganesha Rai Ajit Jadhav Brian D. Peyser Christopher P. Austin Scott E. Martin Anton Simeonov Marc Ferrer Louis M. Staudt Craig J. Thomas 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(6):2349-2354
48.
Ranjan Ku. Sahoo Nikhil Biswas Arijit Guha Nityananda Sahoo Ketousetuo Kuotsu 《药学学报(英文版)》2014,4(5):408-416
The aim of this study was to characterize the provesicle formulation of nateglinide (NTG) to facilitate the development of a novel controlled release system of NTG with improved efficacy and oral bioavailability compared to the currently marketed NTG formulation (Glinate™ 60). NTG provesicles were prepared by a slurry method using the non-ionic surfactant, Span 60 (SP), and cholesterol (CH) as vesicle forming agents and maltodextrin as a coated carrier. Multilamellar niosomes with narrow size distribution were shown to be successfully prepared by means of dynamic laser scattering (DLS) and field emission scanning electron microscopy (FESEM). The absence of drug-excipient interactions was confirmed by Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) studies. In vitro release of NTG in different dissolution media was improved compared to pure drug. A goat intestinal permeation study revealed that the provesicular formulation (F4) with an SP:CH ratio of 5:5 gave higher cumulative amount of drug permeated at 48 h compared to Glinate™ 60 and control. A pharmacodynamic study in streptozotocin-induced diabetic rats confirmed that formulation F4 significantly (P<0.05) reduced blood glucose levels in comparison to Glinate 60. Overall the results show that controlled release NTG provesicles offer a useful and promising oral delivery system for the treatment of type II diabetes.KEY WORDS: Provesicles, Niosomes, Maltodextrin, Nateglinide, In vitro release, Goat intestinal permeation, Hypoglycemic 相似文献
49.
Sanjukta Guha Thakurta Mikail KraftHendrik J. Viljoen Anuradha Subramanian 《Acta biomaterialia》2014,10(11):4798-4810
Chondrocyte-seeded scaffolds were cultured in an ultrasound (US)-assisted bioreactor, which supplied the cells with acoustic energy around resonance frequencies (∼5.0 MHz). Polyurethane-polycarbonate (BM), chitosan (CS) and chitosan–n-butanol (CSB) based scaffolds with varying porosities were chosen and the following US regimen was employed: 15 kPa and 60 kPa, 5 min per application and 6 applications per day for 21 days. Non-stimulated scaffolds served as control. For BM scaffolds, US stimulation significantly impacted cell proliferation and depth-independent cell population density compared to controls. The highest COL2A1/COL1A1 ratios and ACAN mRNA were noted on US-treated BM scaffolds compared to controls. A similar trend was noted on US-treated cell-seeded CS and CSB scaffolds, though COL2A1/COL1A1 ratios were significantly lower compared to BM scaffolds. Expression of Sox-9 was also elevated under US and paralleled the COL2A1/COL1A1 ratio. As an original contribution, a simplified mathematical model based on Biot theory was developed to understand the propagation of the incident US wave through the scaffolds and the model analysis was connected to cellular responses. Scaffold architecture influenced the distribution of US field, with the US field being the least attenuated in BM scaffolds, thus coupling more mechanical energy into cells, and leading to increased cellular activity. 相似文献
50.
Ray U Khan GA Chakraborty K Basuroy S Patra SC Girish G Bhattacharya G Sinha AK 《Journal of thrombosis and thrombolysis》2012,33(3):218-229
Insulin inhibits platelet aggregation through nitric oxide synthesis by stimulating platelet insulin activated nitric oxide
synthase. Impaired platelet insulin activated nitric oxide synthase in acute myocardial infarction (AMI) patients had been
reported and thus our aim was to identify and isolate the factors impairing insulin activated nitric oxide in acute myocardial
infarction patients’ plasma and study its effect on platelets aggregation in vitro. The insulin activated nitric oxide synthase
inhibitor was identified as a protein and was purified from the plasma of AMI subjects using DEAE cellulose and Sephadex G-50
column, molecular weight determined by SDS-PAGE, nitric oxide quantified by methaemoglobin method, inhibitor protein quantified
in plasma by immunoblot and ELISA, platelet aggregation studies done using an aggregometer, thromboxane-A2 in the platelets
determined by radioimmunoassay, 125I-insulin radioligand binding studies done using normal subject platelets. The purified nitric oxide synthase inhibitor protein
was ~66 kDa, concentration in AMI subjects’ plasma varied from 114 to 9,090 μM and was undetected in normal subjects’ plasma.
The inhibitor protein competes with insulin for insulin receptor binding sites. The Incubation of the normal subject PRP with
5.0 μM inhibitor for 30 min followed by 0.4 μM ADP addition caused platelet aggregation in vitro, 130 μM aspirin or 400 μU
insulin/ml addition was able to abrogate 0.4 μM ADP induced platelet aggregation even in the presence of 5.0 μM inhibitor.
A potent inhibitory protein against insulin activated nitric oxide synthase in platelets appears in circulation of AMI subjects
impairing nitric oxide production, potentiating ADP induced platelet aggregation and increasing the thromboxane-A2 level in
platelets. 相似文献