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941.
942.
Bovine herpesvirus-1 (BoHV-1) infection is distributed worldwide and the development of new tools to fight against this pathogen has become extremely important. In this work a recombinant modified vaccinia virus Ankara (MVA) vector expressing the secreted version of glycoprotein D, MVA-gDs, was obtained and evaluated as a candidate vaccine. First, the correct expression, antigenicity, and N-glycosylation of glycoprotein D were confirmed by molecular techniques. Then MVA-gDs was used as parenteral immunogen in BALB/C mice in which a specific anti-gD humoral immune response was induced and maintained for 7?mo. Two doses of MVA-gDs supplemented with cholera toxin delivered by intranasal immunization induced IgA anti-gD humoral immune responses in nasal and bronchopulmonary washes, as well as IgG anti-gD antibodies in serum samples. In order to evaluate the protection conferred by MVA-gDs immunization, a rabbit BoHV-1 challenge assay was performed. A shorter viral excretion period and a reduction in the number of animals shedding BoHV-1 was observed in the group immunized with recombinant MVA-gDs. In conclusion our data encourage further studies to evaluate MVA-gDs, alone or combined with other immunogens, as a candidate vaccine for BoHV-1.  相似文献   
943.
Frontotemporal dementia (FTD) is a clinical entity grouping different diagnostic conditions. FTD can occur in a sporadic form; however in 30-50% of cases a familial form of FTD has been observed. Mutations in the TAU gene were associated to familial FTD linked to chromosome 17. Our aim was to investigated the proportion of FTD cases attributable to TAU gene mutations in an Italian clinical series. We analyzed 38 patients with FTD; of these, 13 had a positive family history of FTD. All TAU gene exons and flanking intronic regions were sequenced. In our familial FTD sample the estimation of TAU gene mutations accounted for a relative low prevalence (7.6%); based on our results we could argue the existence of other mutations in regulatory regions in the TAU gene or, on the other hand, other genes might be responsible for the most cases of familial FTD.  相似文献   
944.
CDT2/L2DTL/RAMP is one of the substrate receptors of the Cullin Ring Ubiquitin Ligase 4 that targets for ubiquitin mediated degradation a number of substrates, such as CDT1, p21 and CHK1, involved in the regulation of cell cycle and survival. Here we show that CDT2 depletion was alone able to induce the apoptotic death in 12/12 human cancer cell lines from different tissues, regardless of the mutation profile and CDT2 expression level. Cell death was associated to rereplication and to loss of CDT1 degradation. Conversely, CDT2 depletion did not affect non-transformed human cells, such as immortalized kidney, lung and breast cell lines, and primary cultures of endothelial cells and osteoblasts. The ectopic over-expression of an activated oncogene, such as the mutation-activated RAS or the amplified MET in non-transformed immortalized breast cell lines and primary human osteoblasts, respectively, made cells transformed in vitro, tumorigenic in vivo, and susceptible to CDT2 loss. The widespread effect of CDT2 depletion in different cancer cells suggests that CDT2 is not in a synthetic lethal interaction to a single specific pathway. CDT2 likely is a non-oncogene to which transformed cells become addicted because of their enhanced cellular stress, such as replicative stress and DNA damage.  相似文献   
945.
Polymorphisms in PTPN22 are associated with many autoimmune diseases; while rs2476601 is supposed to play a major role, other experimental data suggest that rs2488457 may be even more important. Results in myasthenia gravis are controversial. In 356 Italian myasthenic patients and 439 controls genotyped for both polymorphisms, we found that rs2476601 was not associated with myasthenia, presence of autoantibodies, thymus pathology, sex or onset age unlike previous studies on other European populations (confirmed by the present meta-analysis). On the other hand, while rs2488457 was not associated with myasthenia or thymus pathology, we found a correlation of rs2488457 with low autoantibody titers and a trend of association with a less severe disease. Both polymorphisms were in tight linkage disequilibrium in controls, not in patients. Our results suggest that SNPs in this gene different from rs2476601, and/or epigenetic interactions, could play a greater role.  相似文献   
946.
In this study, our aims were to evaluate the reactive oxygen species (ROS) and nitric oxide (NO) generation by monocytes and neutrophils from septic patients and to correlate their levels with clinical outcomes. Forty-nine septic patients and 19 healthy volunteers were enrolled in the study. The ROS and NO production was quantified in monocytes and neutrophils in whole blood by flow cytometry, constitutively, and after stimulation with Staphylococcus aureus and Pseudomonas aeruginosa. Nitric oxide production by monocytes was higher in septic patients compared with healthy volunteers for all conditions and by neutrophils at baseline, and ROS generation in monocytes and neutrophils was higher in septic patients than in healthy volunteers for all conditions. Nitric oxide production by monocytes and neutrophils was decreased at day 7 compared with that at admission (day 0) in survivors at baseline and after stimulation with S. aureus. Reactive oxygen species production by the monocytes and neutrophils was decreased in survivors at day 7 compared with day 0 under all conditions, except by neutrophils at baseline. No difference was found in NO and ROS generation by monocytes and neutrophils between day 7 and day 0 in nonsurvivors. Generation of NO and ROS by neutrophils and monocytes is increased in septic patients, and their persistence is associated with poor outcome.  相似文献   
947.
948.
Diabetes mellitus and cardiovascular diseases act as two sides of the same coin: diabetes is an important risk factor for cardiovascular disease while patients with ischemic cardiovascular diseases often have diabetes or pre-diabetes. As firstly shown by Framingham study, diabetic women have an increased cardiovascular risk about 3.5 fold higher than non diabetic women, against an increase of "only" 2.1 fold found in male subjects. In view of the impact of sexual hormones on glucose homeostasis, the molecular pathways involved in insulin resistance suggest a sex-gender specificity mechanism in the development of diabetic complications leading to the unmet need of sex-gender therapeutic approaches. This has also been seen in other diabetic complications such as renal diseases, which seems to progress at a faster rate in females compared with males and women benefit less from treatment than do men. Of note, none of the trials done so far are primarily designed to assess sex-gender differences in the benefit from a specific intervention strategy, de facto excluding fertile women from experimentation. In order to provide a more evidence based medicine for women and to reach equity between men and women, sex-gender epidemiological reports, preclinical and clinical research are mandatory to evaluate the impact of gender on the outcomes and to improve sex-gender awareness and competency in the health care system. Future studies should consider sex-gender differences in the setting of randomized controlled trials with drugs.  相似文献   
949.

AIMS

To study whether morphologic (foveal thickness, FT) variations of clinically significant macular oedema (CMO) in patients suffering from diabetes following intravitreal pegaptanib sodium (IVP) injection were associated with functional [macular sensitivity (MS) and colour discrimination (CD)] changes.

METHODS

A longitudinal, interventional, non-randomized study was performed. FT was assessed by optical coherence tomography (OCT), MS by microperimetry, best-corrected visual acuity (BCVA) by early treatment diabetic retinopathy study charts (ETDRS) and CD by Farnswoth-Munsell test. The treatment protocol consisted of three consecutive injections (0.3 mg/0.05 ml; baseline, week 6 and week 12). Follow-up checks were scheduled at 18, 24, 36 and 48 weeks, after injections.

RESULTS

Thirty eyes of 30 patients with clinically significant CMO were included for analysis. After IVP a significant decrease of FT occurred with a mean reduction from baseline of 56.9% (P= 0.0001). An improvement of functional parameters was recorded in all patients (BCVA from 18.2 ± 8.5 letters to 25.5 ± 8.4 letters, P < 0.005, MS from 8.6 ± 2.16 dB to 10.6 ± 2.61 dB, P < 0.001, colour analysis from 376.1 ± 125.6 TES to 116 ± 34.6 TES, P= 0.0001). A statistically significant correlation between FT and BCVA as well as MS and CD was also found. Neither ocular nor systemic adverse events were reported.

CONCLUSIONS

Intravitreal pegaptanib significantly reduced FT, with a concomitant improvement of MS and CD. This association emphasizes the efficacy of IVP in the treatment of CMO.  相似文献   
950.
Within the present study hydroxyethyl cellulose-cysteamine conjugates are investigated regarding biocompatibility, in situ gelling, permeation enhancing and efflux pump inhibitory properties. For this purpose, a series of concentrations of sodium periodate was prepared to oxidize HEC leading to ring opening of glucose subunits. The resulting polymers showing varying degrees of oxidation (DO) were then conjugated with cysteamine stabilized via reductive amination. Consequently, HEC-cysteamine conjugates with increasing degree in thiolation were obtained. Since the conjugates are positively charged, potency of cytotoxicity was tested by resazurin assay. In situ gelling properties of the conjugates were studied to investigate change of their viscosity due to inter- and/or intramolecular crosslinking via disulfide bonds. The influence of the presence of the conjugates on transport of rhodamine 123 and fluoresceinisothiocyanate-dextran 4 (FD4) representing model compounds for P-glycoprotein (P-gp) inhibition and permeation enhancing studies, respectively, across Caco-2 cell monolayers was determined. The conjugates showed a degree of thiolation in the range of 316-2158 μmol/g. Within 30 min, dynamic viscosity of the conjugate with the lowest degree of thiolation 0.5% (m/v) increased up to 300-fold. The conjugates showed a degree of thiolation-dependent increase in cytotoxicity but they all were found comparatively low cytotoxic. The addition of the conjugate with thiol group content of 1670 μmol/g resulted in the highest improvement in the transport of both rhodamine 123 and FD4 as compared to buffer control. Accordingly, the degree of thiolation strongly influences the properties of the conjugates and the modulation of the degree of thiolation could be exploited for development of various drug delivery systems.  相似文献   
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