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51.

Background  

HBV infection is a serious global heath problem. It is crucial to monitor this disease more closely with a non-invasive marker in clinical trials. We aimed to evaluate the predictive value of serum hyaluronate for the presence of extensive liver fibrosis and inflammation.  相似文献   
52.
OBJECTIVE: To determine the feasibility of uterine tissue ablation in vivo using a transvaginal focused ultrasound applicator guided by ultrasound imaging. DESIGN: Randomized in vivo animal study. SETTING: Academic research environment. ANIMAL(S): Healthy anesthetized sheep. INTERVENTION(S): Uterine treatment location was determined using a computerized targeting system. Five sonications 10 seconds in duration and averaging 2,000 W/cm(2) of focal ultrasound intensity were applied in each animal's uterus. Animals were euthanized either immediately or 2, 7, or 30 days post-treatment. MAIN OUTCOME MEASURE(S): Gross and microscopic analysis of the dissected uterus was used to quantitatively and qualitatively determine the ablated region and treatment side effects. RESULT(S): Treatments resulted in coagulative necrosis. Histopathological analysis showed that over 7 days, inflammatory cells appeared and smooth muscle bundles regenerated. By day 30, treated tissues healed and scar tissue formed. None of the animals showed abnormal behavior or medical problems. Complications in three animals were damage to the vaginal wall and colon, possibly due to inadequate applicator cooling and an empty bladder during treatment. CONCLUSION(S): Transvaginal image-guided high-intensity focused ultrasound has potential for treating uterine fibroids. Further safety testing of this treatment will prepare it for human use.  相似文献   
53.
We determined the x-ray structure of bovine aquaporin 0 (AQP0) to a resolution of 2.2 A. The structure of this eukaryotic, integral membrane protein suggests that the selectivity of AQP0 for water transport is based on the identity and location of signature amino acid residues that are hallmarks of the water-selective arm of the AQP family of proteins. Furthermore, the channel lumen is narrowed only by two, quasi-2-fold related tyrosine side chains that might account for reduced water conductance relative to other AQPs. The channel is functionally open to the passage of water because there are eight discreet water molecules within the channel. Comparison of this structure with the recent electron-diffraction structure of the junctional form of sheep AQP0 at pH 6.0 that was interpreted as closed shows no global change in the structure of AQP0 and only small changes in side-chain positions. We observed no structural change to the channel or the molecule as a whole at pH 10, which could be interpreted as the postulated pH-gating mechanism of AQP0-mediated water transport at pH >6.5. Contrary to the electron-diffraction structure, the comparison shows no evidence of channel gating induced by association of the extracellular domains of AQP0 at pH 6.0. Our structure aids the analysis of the interaction of the extracellular domains and the possibility of a cell-cell adhesion role for AQP0. In addition, our structure illustrates the basis for formation of certain types of cataracts that are the result of mutations.  相似文献   
54.
AIMS: The goal of this study was to evaluate whether the intravaginal electrode used to perform vaginal electrical stimulation could induce acute changes on the cystometrograms and urethral pressure profiles (UPP) recordings. METHODS: Three consecutive urodynamic examinations were performed on 30 women with stress urinary incontinence (SUI) symptoms. The first exam was performed without the electrode, the second with the electrode inserted into the vagina, but with the stimulator switched off and the third with the stimulator turned on. We used the INNOVA (Empi) stimulator with electrical parameters set at 50 Hz and 60 mA and on an intermittent cycle during the cystometries and a continuous stimulation during the UPP. The data of functional profile length (FPL), maximum urethral closure pressure (MUCP), and area of the resting UPP, as well as the filling sensations and its respective bladder volumes during the cystometries, were compared. With regard to the cystometries. RESULTS: No effect of the electrode was observed on cystometry. However, the simple presence of the electrode improved the FPL, MUCP, and areas of the UPP similar to those when the stimulation was applied. CONCLUSIONS: We conclude that, the presence of the intravaginal electrode induces changes in the UPP not related to the stimulation itself. The physiotherapeutic effect of the electrode itself is still to be evaluated.  相似文献   
55.
Immunization with peptide mimetics of carbohydrate antigens can induce functional carbohydrate-reactive antibodies. Here, we examine the immune characteristics of alternative approaches in prime and boost strategies using glycosylated HIV-1 envelope protein and model tumor associated carbohydrate antigens. Our results indicate that peptide mimotopes either in a DNA or carrier-conjugated format can induce comparable levels of IgM and IgG. Carbohydrate boosting of peptide-primed animals does not affect end-point titer, however, boosting mediates a stable long lasting carbohydrate reactive IgM response, not achievable by carbohydrate immunization alone. Boosting with carbohydrate in animals primed with DNA- or peptide-conjugate, facilitates the induction of detectable IgG with a dominant IgG2a isotype. Immunization with HIV-1 envelope glycoprotein of peptide-primed animals induces different IgG isotype profiles with a dominant IgG1 antibody. We observed that HIV-1 envelope glycoprotein immunization of peptide primed mice induces a cross-reactive cellular response, as detected by cytokine secretion, which lends to IFN-gamma production upon splenocyte stimulation and CTL activity against recombinant vaccinia virus infected cells after in vitro stimulation. DNA immunization with mimotope, inclusion of a T-cell epitope from the HIV-1 envelope protein in the expression cassette and co-administration with IL-12 or GM-CSF encoding plasmids activate a cellular response to the HIV-1 envelope protein.  相似文献   
56.
Peyronie's disease: a review   总被引:3,自引:0,他引:3  
PURPOSE: We provide a current review of Peyronie's disease. MATERIALS AND METHODS: We reviewed the world peer reviewed literature on the pathology, pathogenesis, diagnosis and treatment of Peyronie's disease. RESULTS: The incidence of Peyronie's disease has continuously increased during the last 30 years. However, fewer patients need prosthesis surgery as the sole treatment option because of earlier diagnosis, improved medical therapy, refinement in surgical technique and better understanding of the basic sciences of the disease. CONCLUSIONS: Currently patients with Peyronie's disease have had improvements in prognosis and experienced an expansion of the available therapeutic options.  相似文献   
57.
PURPOSE: To describe MR-guided access to the retropharynx for precise fine-needle aspiration cytology (FNAC), and other indications for needle placement. MATERIALS AND METHODS: A retrospective review was made of 15 procedures that had been performed on 14 patients. These patients had a retropharyngeal mass on MRI and had undergone MR-guided minimally invasive access to the retropharynx for either diagnostic or therapeutic intervention in the period of October 1989 to January 2000. RESULTS: All 14 patients underwent MR-guided access to the retropharynx for FNAC without immediate or delayed complications. MRI confirmed that the biopsy needle was within the retropharyngeal mass in all patients. MR-guided FNAC revealed five true-positive, five true-negative, four indeterminate, and no false-positive cases. Ten of the 14 patients (71%) had diagnostic aspirations. In one patient with retropharyngeal extension of carcinoma, an MR-guided approach was used for the experimental interstitial laser therapy (ILT). CONCLUSION: The results suggest that an MR-guided retromandibular approach to biopsy of retropharyngeal mass is minimally invasive and safe.  相似文献   
58.
The expected incisional hernia rate is between 11-20% after laparotomy. Using mesh repair the results of the hernioplasty have recently improved. However the complication of mesh implants--especially in intraperitoneal position--can be life threatening. Additionally the appropriate mesh is expensive. We tried to create a mesh, which can be used intraperitoneally and generates adhesion in the abdominal wall, but keeps the intraabdominal organs adhesion free. Our experiments were divided into four groups. In the first we used different materials to cover the intraperitoneal side of polypropylene mesh. In the second phase three different pore-sized meshes were compared. In the third part the biological behavior of three different material-reduced meshes were investigated. Based on our previous results in the last session we used only silicone membrane protected material-reduced polypropylene meshes to cover the abdominal defects. Our experiments have shown that intraperitoneal implant with silicone-covered Vypro (Ethicon)/Premilene (B. Braun Medical) mesh significantly decreases the formations of adhesion.  相似文献   
59.
The mechanism of lithium action, an effective treatment for bipolar disease, is still unknown. The present study examined the role of nitric oxide (NO) and prostaglandin systems in lithium modulation of acetylcholine in mesenteric vascular bed of rats by cannulating superior mesenteric artery. Acetylcholine (ACh) or sodium nitroprusside was injected under constant controlled flow induced by phenylephrine; therefore, changes in perfusion pressure reflect changes in resistance. Although 0.5 mM or 1 mM lithium-pretreatment of vascular bed causes reduction in ACh-response, 1.5 mM lithium induced no changes and 2 and 2.5 mM lithium potentiated ACh-induced mesenteric vascular bed relaxation compared to control group. Pretreatment of vascular bed with L-NAME or indomethacin decreased ACh-induced relaxation in 2 concentrations of 0.5 and 2 mM of lithium. The vasorelaxation response to sodium nitroprusside, the NO donor, was not different among lithium groups (0.5 and 2 mM) and controls. In conclusion, there is a dual modulation of endothelium-dependent relaxation, including an inhibitory effect at lower dose and a stimulating effect at higher dose of lithium in rat mesenteric vascular bed. NO synthesis or cyclooxygenase inhibition decreased vasorelaxation in both lower and higher doses of lithium, suggesting a role for NO and prostaglandin in this effect.  相似文献   
60.

Introduction  

Chronic granulomatous disease (CGD) is a rare inherited condition resulting from mutations in the genes that encode the proteins of the NADPH oxidase enzyme in phagocytes, rendering these cells incapable of killing invading pathogens.  相似文献   
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