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排序方式: 共有1237条查询结果,搜索用时 15 毫秒
51.
Horváth S Kis Z Boldogköi Z Nógrádi A Toldi J 《The European journal of neuroscience》2002,15(5):937-943
This study examines the hypothesis that neuronal infectivity and the spreading of the pseudorabies virus (PRV) through the synapses in the central nervous system (CNS) are influenced by the oestrogen levels. The arcuate nucleus (ARC) and the subfornical organ (SFO) were chosen as models for analysis; the neurons in both structures possess oestrogen receptors and are mutually connected. A genetically engineered pseudorabies virus (Ba-DupLac) was used as a transneuronal tract tracer. This virus is taken up preferably by axon terminals, and transported very specifically through the synapses in a retrograde manner. Ba-DupLac was injected into the ARC of rats, followed by monitoring of the PRV-immunoreactivity (PRV-IR) in the SFO 72 h following inoculation. We found no PRV immunolabelling in the SFO of ovariectomized (OVX) rats, or in those OVX animals that received oestrogen shortly (4 h) before PRV infection (OVX + E 4 h). In contrast, in those OVX animals that received oestrogen 12 h before PRV infection (OVX + E 12 h), and also in intact control animals, PRV-IR was demonstrated in the SFO in all cases. Surprisingly, a reverse labelling was observed in the OVX rats; PRV-IR appeared in the pyriform cortex, whereas PRV-IR could not be detected in the control and OVX + E 12 h animals. As far as we are aware, this is the first study to demonstrate that transneuronal PRV labelling depends on the effects of oestrogen on certain CNS structures and connections. 相似文献
52.
Nagy N Maeda A Bandobashi K Kis LL Nishikawa J Trivedi P Faggioni A Klein G Klein E 《International journal of cancer. Journal international du cancer》2002,100(4):433-440
The SH2 domain containing SH2D1A protein has been characterized in relation to the X-linked lymphoproliferative disease (XLP), a primary immunodeficiency that leads to serious clinical conditions after Epstein-Barr virus (EBV) infection. The SH2D1A gene is mutated in the majority of XLP patients. We previously detected SH2D1A in activated T and NK cells, but not in B lymphocytes. We have found SH2D1A protein in Burkitt lymphoma (BL) lines, but only in those that carried EBV and had a Group I (germinal center) phenotype. All the EBV-carrying Group III (immunoblastic) and the EBV-negative BL lines tested were SH2D1A-negative. Motivated by these differences, we studied the impact of EBV and the cellular phenotype on SH2D1A expression. We approached the former question with BL sublines after both the loss of the virus and subsequent reinfection. We also tested original EBV-negative BL lines carrying transfected EBV genes, such as EBNA1, EBNA2, EBNA6, EBER1, 2 and LMP1, respectively. In our experiments, no direct relationship could be seen between EBV and SH2D1A expression. We modified the phenotype of the Group I BL cells by LMP1 transfection or CD40 ligation. The phenotypic changes, indicated by expression of immunoblastic markers, e.g., SLAM, were accompanied by downregulation of SH2D1A. It seems, therefore, that the presence of EBV and the phenotype of the cell together regulate SH2D1A expression in the BL cells. It is possible that SH2D1A is expressed in a narrow window of B cell development represented by germinal center cells. 相似文献
53.
Laurent S Detry O Detroz B DeRoover A Joris J Honoré P Louis E Belaïche J Jacquet N 《Acta chirurgica Belgica》2002,102(4):253-255
Strictureplasty for obstructive Crohn's disease is still controversial because lesions are left in place and the suture is performed on a diseased bowel. Many surgeons prefer to perform bowel resection, hoping for fewer complications and a lower recurrence rate. In this paper, the authors reports their strictureplasty experience. They performed a systematic retrospective review of the patients suffering from Crohn's disease who underwent strictureplasties during a 10-year period in the abdominal surgery department of the University Hospital of Liège Sart Tilman, and studied the short- and long-term clinical results of 68 strictureplasties performed in 18 patients. Median follow-up was 63 months (range 12 to 144). Mortality was 0% and septic morbidity was 11% (one wound abscess and one leakage). Among the 16 patients available for the latest follow-up, symptomatic stenotic recurrence had to be medically treated in hospital for 4 patients (25%) with a recurrence delay range of 19 to 49 months. Stenosis recurrence needed re-intervention in one patient 48 months after surgery: stenosis occurred at a distance from the corrected site. These results confirmed that strictureplasty is a safe and efficient procedure in selected patients undergoing surgery for obstructive Crohn's disease. 相似文献
54.
Association studies of Parkinson's disease and parkin polymorphisms 总被引:17,自引:0,他引:17
55.
The survey was undertaken by ESWI in order to investigate the comparability of the laboratory diagnostic methods and the influenza surveillance systems used in 24 European countries. The results indicate considerable consensus in the general approaches to collection and use of clinical specimens, rapid diagnostic techniques, virus isolation techniques in eggs or/and MDCK cell lines, virus identification and use of inhibition of hemagglutination (IHA) and complement fixation (CF) tests for serological diagnostics. However, the details of the techniques used are somewhat heterogeneous: antigen detection methods (immunofluorescence versus immuno adsorbent assay), isolation methods (eggs versus tissue culture), reagents (locally produced, WHO, commercial) are not always equivalent and results are therefore not really comparable. Some of these discrepancies are due to a lack of resources or a lack of priority for influenza in the country. The greatest differences between individual countries exist in the epidemiological part of surveillance programmes. The mode of collection of influenza related mortality and absentism from work varies considerably in different countries. These findings indicate the need to harmonize viral procedures and surveillance systems in European countries in order to improve validity and comparability of results and as a prerequisite for early information on influenza etiology and spread. 相似文献
56.
57.
58.
Possibilities and limitations of fibrin glue usage in nephron-sparing surgery: experimental study 总被引:4,自引:0,他引:4
Stojkovic I Savic V Djokic M Balint B Ljubenovic S Ignjatovic I 《Urologia internationalis》2005,74(4):355-360
INTRODUCTION: The possibilities and limitations of fibrin glue (FG) usage in nephron-sparing surgery were studied. MATERIALS AND METHODS: A prospective experimental study was carried out in 50 pigs: 30 with polar resection, and 20 with mediorenal wedge resection of the kidney. Hemostatic sutures, FG, and FG with a muscle 'cup' in animals with polar resection of the kidney were compared. FG and sutures in animals with the wedge resection of the kidney were studied as well. Bleeding, hot ischemia time, complication rate, and additional scarring were also analyzed. RESULTS: Suture hemostasis is safe but with significant adverse effects in both polar and wedge resection of kidney. FG was not efficient as a sole hemostatic agent for polar resection. It was as efficient as hemostatic suture for wedge resection of the kidney. FG with a muscle 'cup' on a pole of the kidney achieved good results in animals with polar resection of the kidney. Histological analysis confirmed better results with FG because of both the less intense and smaller area of additional scarring. CONCLUSION: FG is a reliable and efficient hemostatic agent for nephron-sparing surgery whenever both sided gluing is possible. 相似文献
59.
Vaccinia virus mediated p53 gene therapy for bladder cancer in an orthotopic murine model 总被引:3,自引:0,他引:3
Fodor I Timiryasova T Denes B Yoshida J Ruckle H Lilly M 《The Journal of urology》2005,173(2):604-609
PURPOSE: We determined if vaccinia virus (VV) mediated delivery of human tumor suppressor p53 is safe and effective for bladder tumor therapy in an orthotopic murine model. MATERIALS AND METHODS: We used recombinant VV (rVV) vectors to express transgenes in murine bladder cancer MB-49 cells in culture and those growing orthotopically in syngeneic mice. Cultured MB-49 cells were infected with rVV expressing reporter genes (rVV-L15) or p53 (rVV-TK-53) to measure virus infection and apoptosis induction. Orthotopic MB-49 tumors in C57/Bl6 mice were treated with intravesical instillation of rVV, and the tumor incidence, survival and transgene expression were determined. RESULTS: Productive virus infection in vitro was observed in MB-49 cells, although at somewhat lower efficiency than in African Green Monkey kidney CV-1 cells (American Type Culture Collection, Manassas, Virginia). Expression of transgenes in vitro correlated with the virus dose. Cells infected with rVV underwent apoptosis with rVV-TK-53 inducing far greater cell death than rVV-L15. The rVV-L15 virus had no effect on tumor incidence but it increased mean survival compared with control. Instillation of rVV-TK-53 decreased the tumor incidence and 33% of mice survived treatment. At necropsy all nonsurviving mice had bladder tumor, whereas 2 survivors in the rVV-TK-53 treated group were tumor-free. Immunohistochemistry of tumors detected expression of the human p53 gene product in tumor cells. CONCLUSIONS: To our knowledge we report for the first time that recombinant vaccinia virus expressing human p53 can induce the death of MB-49 tumor cells in vivo, not only through the lytic effect of the virus, but also through expression of the death inducing p53 transgene. Further studies are needed to shed light on the mechanisms of rVV-TK-53 mediated tumor apoptosis and the antitumor immune response. 相似文献
60.
Cloning and characterization of cyclooxygenase-1b (putative cyclooxygenase-3) in rat 总被引:4,自引:0,他引:4
Snipes JA Kis B Shelness GS Hewett JA Busija DW 《The Journal of pharmacology and experimental therapeutics》2005,313(2):668-676
A splice variant of cyclooxygenase-1 (COX-1), COX-1b (previously termed as COX-3), has been identified in canine tissues as an acetaminophen-sensitive isoform, but the sequence of COX-1b mRNA and the encoded protein are not known in rats. We cloned and sequenced rat COX-1b mRNA from cerebral endothelial cells. Sequence analysis indicated that the 98-base pair intron-1 of COX-1 gene remains unprocessed in the COX-1b mRNA, causing a frameshift mutation and a 127-amino acid open reading frame with no sequence similarity with known cyclooxygenases. Transient and permanent transfection of COS-7 cells with a vector containing the rat COX-1b cDNA resulted in synthesis of a protein of the expected size. We generated an affinity-purified polyclonal antibody against the rat COX-1b protein. Western blot analysis of rat tissues using this antibody demonstrated the likely existence of rat COX-1b protein in vivo with the highest expression in heart, kidney, and neuronal tissues. Our results on both stable and on transiently transfected COS-7 cells suggest that rat COX-1b does not have cyclooxygenase activity and does not have any effect on the inhibition of prostaglandin production by acetaminophen. Because this protein has a completely different amino acid sequence than COX-1 and COX-2 and it does not have cyclooxygenase activity, we suggest a name cyclooxygenase variant protein to distinguish it from the known prostaglandin-synthesizing cyclooxygenase isoforms. 相似文献