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41.
42.
Kuo LJ Chiou JF Tai CJ Chang CC Kung CH Lin SE Hung CS Wang W Tam KW Lee HC Liang HH Chang YJ Wei PL 《International journal of colorectal disease》2012,27(5):613-621
Background
Pathologic complete response has been proven to have oncological benefits for locally advanced rectal cancer treated with chemoradiation therapy. The aims of this study are to analyze and determine the factors to predict pathologic complete response for patients treated with preoperative neoadjuvant therapy.Methods
Patients with biopsy-proven, locally advanced rectal cancer were treated neoadjuvantly followed by radical surgical resection. Tumors were re-assessed after completing chemoradiation, including pelvic magnetic resonance images, colonoscopic examination, and re-biopsy. The results of examination were compared with the final pathologic status.Results
A retrospective chart review of 166 patients was conducted. Twenty-five patients (15.1%) had pathologic complete response after chemoradiation. The 5-year overall survival rates were better in the complete response group than the residual tumor group (91.1% vs. 70.8%; P?=?0.047), and there were also significant differences in the 5-year disease-free survival rates between these two groups (91.1% vs. 70.2%; P?=?0.027). The prediction rates for pathologic complete response by re-biopsy, magnetic resonance images, and colonoscopy were 21.4%, 33.3%, and 53.8%, respectively. In addition, when we further combine the results of colonoscopic findings and re-biopsy, the prediction rate for pathologic complete response reached 77.8% (P?=?0.009).Conclusions
Combining the results of the re-biopsy and post-treatment colonoscopic findings, we can achieve a good prediction rate for pathologic complete response. Post-treatment magnetic resonance images are not useful tools in predicting tumor clearance following chemoradiation. 相似文献43.
A. M. Aiken J. B. Haddow N. R. A. Symons S. Kaptanis A. C. Katz-Summercorn D. Debnath H. Dent S. Tayeh V. Kung S. Clark J. Gahir S. Dindyal S. Farag A. Lazaridis C. P. Bretherton S. Williams A. Currie H. West J. Davies S. Arora A. Kheraj B. M. Stubbs N. Yassin S. Mallappa G. Garrett S. Hislop A. Bhangu Y. Abbey I. Al-Shoek U. Ahmad G. Sharp A. Memarzadeh A. Patel F. Ali H. Kaderbhai C. H. Knowles 《Hernia》2013,17(5):657-664
Purpose
Evidence regarding whether or not antibiotic prophylaxis is beneficial in preventing post-operative surgical site infection in adult inguinal hernia repair is conflicting. A recent Cochrane review based on 17 randomised trials did not reach a conclusion on this subject. This study aimed to describe the current practice and determine whether clinical equipoise is prevalent.Methods
Surgeons in training were recruited to administer the Survey of Hernia Antibiotic Prophylaxis usE survey to consultant-level general surgeons in London and the south-east of England on their practices and beliefs regarding antibiotic prophylaxis in adult elective inguinal hernia repair. Local prophylaxis guidelines for the participating hospital sites were also determined.Results
The study was conducted at 34 different sites and received completed surveys from 229 out of a possible 245 surgeons, a 93 % response rate. Overall, a large majority of hospital guidelines (22/28) and surgeons’ personal beliefs (192/229, 84 %) supported the use of single-dose pre-operative intravenous antibiotic prophylaxis in inguinal hernia repair, although there was considerable variation in the regimens in use. The most widely used regimen was intravenous co-amoxiclav (1.2 g). Less than half of surgeons were adherent to their own hospital antibiotic guidelines for this procedure, although many incorrectly believed that they were following these.Conclusion
In the south-east of England, there is a strong majority of surgical opinion in favour of the use of antibiotic prophylaxis in this procedure. It is therefore likely to be extremely difficult to conduct further randomised studies in the UK to support or refute the effectiveness of prophylaxis in this commonly performed procedure. 相似文献44.
An enzymatic approach to configurationally rare trans‐androsteronyl‐α‐glucoside and Its potential anticancer application 下载免费PDF全文
Feng‐Pai Chou Chia‐Tse Tsai Ya‐Sheng Chiou Yi‐Ju Chen Meng‐Erh Li Ting‐Wei Guo Jason WenJay Lyu Sheng‐Hao Chou Tung‐Kung Wu 《Chemical biology & drug design》2017,89(1):61-66
Enzymatic glycosylation of sterols/steroids with glycosyltransferase HP0421 shows protein plasticity on generation of configurationally rare steryl‐α‐glucosides. Investigation of trans‐androsteronyl‐α‐glucoside on tamoxifen‐treated MCF‐7 breast cancer cells shows dose‐dependent depression of cell viability and enhanced drug effectiveness, illustrating a new avenue for the production of novel steryl‐α‐glucosides with useful biological activities. 相似文献
45.
No relationship between prenatal androgen exposure and autistic traits: convergent evidence from studies of children with congenital adrenal hyperplasia and of amniotic testosterone concentrations in typically developing children 下载免费PDF全文
46.
47.
Chih-Hui Yang Chih-Yu Wang Keng-Shiang Huang Chao-Pin Kung Yi-Ching Chang Jei-Fu Shaw 《International journal of pharmaceutics》2014
This paper demonstrates a simple and easy approach for the one-step synthesis of Fe3O4-chitosan composite particles with tadpole-like shape. The length and diameter of the particles were adjustable from 638.3 μm to ca. 798 μm (length), and from 290 μm to 412 μm (diameter) by varying the flow rate of the dispersed phase. Mitoxantrone was used as the model drug in the drug release study. The encapsulation rate of the drug was 71% for chitosan particles, and 69% for magnetic iron oxide-chitosan particles, respectively. The iron oxide-chitosan composite particles had a faster release rate (up to 41.6% at the third hour) than the chitosan particles (about 24.6%). These iron oxide-chitosan composite particles are potentially useful for biomedical applications, such as magnetic responsive drug carriers, magnetic resonance imaging (MRI) enhancers, in the future. 相似文献
48.
49.
R Isfort D Jones R Kost R Witter H J Kung 《Proceedings of the National Academy of Sciences of the United States of America》1992,89(3):991-995
Retroviruses and herpesviruses are naturally occurring pathogens of humans and animals. Coinfection of the same host with both these viruses is common. We report here that a retrovirus can integrate directly into a herpesvirus genome. Specifically, we demonstrate insertion of a nonacute retrovirus, reticuloendotheliosis virus (REV), into a herpesvirus, Marek disease virus (MDV). Both viruses are capable of inducing T lymphomas in chickens and often coexist in the same animal. REV DNA integration into MDV occurred in a recently attenuated strain of MDV and in a short-term coinfection experiment in vitro. We also provide suggestive evidence that REV has inserted into pathogenic strains of MDV in the past. Sequences homologous to the REV long terminal repeat are found in oncogenic MDV but not in nononcogenic strains. These results raise the possibility that retroviral information may be transmitted by herpesvirus and that herpesvirus expression can be modulated by retroviral elements. In addition, retrovirus may provide a useful tool to characterize herpesviral function by insertional mutagenesis. 相似文献
50.
Diversity and structure of human T-cell receptor beta-chain variable region genes. 总被引:23,自引:13,他引:23 下载免费PDF全文
P Concannon L A Pickering P Kung L Hood 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(17):6598-6602
The nucleotide sequences of 27 T-cell receptor beta cDNA clones isolated from a human peripheral lymphocyte library were determined and compared to five additional published sequences. These cDNA clones represent 22 distinct T-cell receptor beta-chain variable region (V beta) gene segment sequences, which fall into 15 different V beta gene subfamilies, each containing six or fewer members. From this analysis, we estimate that the repertoire of expressed human V beta genes is less than 59, apparently much smaller than the immunoglobulin heavy chain and light chain variable region (VH and VL) repertoires. Variability plots comparing these human V beta regions with each other and with published mouse V beta regions provide evidence for only four hypervariable regions homologous to those seen in comparisons of immunoglobulin V regions. Somatic hypermutation appears to be used infrequently, if at all, in these V beta genes. 相似文献