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91.
92.
When virus-specific antiserum was injected into the hemocoel of aphids before they acquired virus by feeding on infected leaves, transmission of the virus was consistently either reduced or prevented by the homologous antiserum when compared with heterologous or control antiserum. The procedure was useful for studying both the transmission of the RPV isolate of barley yellow dwarf virus by Rhopalosiphum padi and the transmission of the MAV isolate by Macrosiphum avenae.Tests with injected R. padi provided additional support for the role of transcapsidation (genomic masking) in the dependent transmission of the MAV isolate by R. padi from mixed infections of RPV and MAV. Although injection of MAV-antiserum prevented transmission of MAV by control aphids, R. padi injected with MAV-antiserum transmitted MAV from leaves infected by both MAV and RPV as readily as when injected with control serum.  相似文献   
93.
94.
Summary Origins of afferents to the cerebellar cortex from the brainstem were explored in turtles by means of the horseradish peroxidase (HRP) technique. Following relatively large injections involving all cortical layers, HRP label was observed in neural perikarya of the following structures: 1) contralateral reticular formation just lateral and ventral to the hypoglossal nucleus; 2) a few cells in the central gray of the cervical spinal cord; 3) neurons scattered in the dorsolateral, ventromedial and descending vestibular nuclei, mainly ipsilaterally; 4) a few solitary cells in the mesencephalic and medulalry tegmentum; 5) the nucleus isthmi magnocellularis caudalis on the ipsilateral side; 6) a group of small cells in the isthmic tectum; 7) the ipsilateral nucleus of the optic tract; 8) a prominent group of small cells in the isthmic region just rostral to the vestibular complex ipsilaterally. Most of these cells were localized within the so called nuclei gustatorius secundarius,-lemnisci lateralis and-isthmi parvocellularis. This parvocellular isthmic complex (PIC) was the only region containing labelled cells when small injections restricted to the molecular layer were achieved. We interpret the PIC as a source of climbing fibers, possibly corresponding to the mammalian inferior olive which migrates from the alar plate to its' ventral destination during ontogenesis. Connecting axons were sometimes homogeneously stained which permitted the tracing of connecting pathways. Contorted axon branches stained by anterograde HRP transport were found concentrated in cerebellar and superior vestibular nuclei and sparsely distributed in other vestibular nuclei.  相似文献   
95.
Four new hopane-type saponins, glinusides F, G, H, and I (1-4), and the known succulentoside B (5), as well as the two known flavones 5,7,4'-trihydroxyflavone-6,8-di-C-glucoside (vicenin-2) and 5,7,4'-trihydroxyflavone-8-C-sophoroside (vitexin-2' '-O-glucoside), were isolated from the seeds of Glinus lotoides growing in Ethiopia. On the basis of the spectroscopic data analysis, including 2D NMR and HRESIMS, the new structures were characterized as 3beta-O-beta-D-xylopyranosyl-6alpha-O-beta-D-xylopyranosyl-16beta-O-beta-D-xylopyranosyl-22-hydroxyhopane (1), 3beta-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-6alpha,16beta-dihydroxy-22-O-alpha-L-rhamnopyranosylhopane (2), 3beta-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl-6alpha-O-beta-D-xylopyranosyl-16beta-hydroxy-22-O-alpha-L-rhamnopyranosylhopane (3), and 3beta-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-d-xylopyranosyl-6alpha-O-beta-D-xylopyranosyl-16beta-O-beta-D-xylopyranosyl-22-hopane (4).  相似文献   
96.
A single recombinant immunoglobulin G1 (IgG1) anti-RhD antibody (MonoRho) was compared with a currently used polyclonal anti-RhD product (Rhophylac) in a phase 1 study for safety, efficacy of Rhesus D (RhD)-positive red blood cell (RBC) clearance, and prevention of RhD immunization in RhD-negative men challenged with 15 mL RhD-positive RBCs. Both the polyclonal product and recombinant anti-RhD effectively cleared RhD-positive RBCs after intravenous and intramuscular injection. The recombinant anti-RhD demonstrated a slower clearance rate compared with the polyclonal anti-RhD. There was no dose response, and there was considerable variation among subjects who received the same dose of recombinant anti-RhD. Interestingly, RhD-positive RBC clearance rates were strongly associated with Fcgamma receptor IIA (FcgammaRIIA) and FcgammaIIIA but not with FcgammaIIIB polymorphisms. Subjects homozygous for FcgammaRIIA-131H or FcgammaRIIIA-158V allotypes showed a faster clearance rate compared with both the heterozygote and the corresponding alternative homozygote allotypes. A similar but less marked trend was seen for the polyclonal anti-RhD. Despite the variation in clearance rates there was no evidence of anti-RhD alloantibodies in any of the subjects at +6 months after the RBC challenge.  相似文献   
97.
Small bowel adenocarcinomas are remarkable for their rarity, difficult diagnosis and poor prognosis. Here we report an unusual case of a 33-year-old patient in whom infiltrative adenocarcinoma of the small bowel was diagnosed after a 10-year history of Crohn's disease. In most previously reported cases, detection of Crohn's disease was subsequent to that of carcinoma of the small bowel or the patients involved had an even longer history of the disease. Our literature review suggests that the risk of small bowel adenocarcinoma is higher in patients with Crohn's disease than in the overall population. We present details on epidemiology as well as clinical and diagnostic aspects of this rare disease entity.  相似文献   
98.
Polyclonal intravenous immunoglobulin (IVIg) treatment reduces crossmatch positivity and increases rates of transplantation in highly sensitised patients (HS). We quantified the panel reactive antibody (PRA) by microlymphocytotoxicity (MLCC), and we analysed anti-HLA class I and class II IgG specific antibody repertoire by Luminex before and after IVIg infusion alone in HS patients awaiting kidney transplantation. Five patients received three monthly infusions of 1 g/kg of IVIg. Serum samples collected pre and post IVIg treatment were submitted for PRA analysis by MLCC. Anti-class I and anti-class II antibody specificities were then tested by Luminex. We focused on the anti-HLA class I and class II antibodies directed against HLA expressed by a previous graft. We also analysed the anti-HLA antibody repertoire in three patients who had not received IVIg infusion. The PRA level determined by MLCC decreased significantly in one of the five patients, dropping from 40% to 17%. The Luminex assay showed fluctuations of the anti-HLA antibody levels over time, but no significant longterm modifications of the anti-HLA antibody repertoire were observed, even in the patient with a strong and prolonged reduction of the PRA determined by MLCC. Our results show that IVIg at 1 g/kg is not sufficient to reduce PRA and does not modify the repertoire of specific anti-HLA antibody determined by Luminex.  相似文献   
99.
Benden C, Faro A, Worley S, Arrigain S, Aurora P, Ballmann M, Boyer D, Conrad C, Eichler I, Elidemir O, Goldfarb S, Mallory GB, Mogayzel PJ, Parakininkas D, Solomon M, Visner G, Sweet SC, Danziger‐Isakov LA. Minimal acute rejection in pediatric lung transplantation – Does it matter?.
Pediatr Transplantation 2010: 14:534–539. © 2010 John Wiley & Sons A/S. Abstract: In adult lung transplantation, a single minimal AR episode is a significant predictor of BOS independent of other factors. However, the significance of single minimal AR episodes in children is unknown. A retrospective, multi‐center analysis was performed to determine whether isolated single AR episodes are associated with an increased BOS risk in children. Risk factors for BOS, death, or re‐transplantation, and a combined outcome of BOS, death, or re‐transplantation were assessed. Original data included 577 patients (<21 yr of age). A total of 383 subjects were eligible for the study. Fifteen percent of patients developed BOS, and 13% of patients either died or underwent re‐transplant within one‐yr post‐transplant. In the multivariable survival model for time to BOS, there was no significant risk to developing BOS after a single minimal AR (A1) episode (HR 1.7, 95% CI 0.64–4.8; p = 0.28). Even after a second minimal AR episode, no significant risk for BOS was appreciated. However, a single episode of mild AR (A2) was associated with twice the risk of BOS within one‐yr post‐transplant. In this select cohort, a single minimal AR episode was not associated with an increased risk for BOS within one yr following lung transplantation, in contrast to previous reports in adults.  相似文献   
100.
BACKGROUND: Focal atrophy is presumed to be an indirect forerunner of prostate cancer. The aim of this study was to examine genetic alterations in prostate epithelia deriving from atrophic areas and compare these findings with those of cells deriving from paired prostate cancer in the same patient. METHODS: Formalin fixed paraffin wax-embedded prostatectomy specimens from 20 prostate cancer patients were utilized in this study. Comparative Genomic Hybridization (CGH) was performed on atrophic areas. To validate the CGH results, Fluorescence in Situ Hybridization (FISH) analysis was performed on atrophic areas and paired cancer tissue. RESULTS: Gain of the whole chromosome X was found as sole aberration in seven (70%) atrophic tissues by CGH. A gain of centromere X was observed in 13 (68.4%) atrophic areas and in 18 (90%) cancer tissues using FISH. CONCLUSIONS: Our investigation reconfirms the genetical instability of cells of the atrophic acini and attention of relevance of gain of chromosome X in atrophic areas.  相似文献   
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