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991.
A new series of pyrazole, phenylpyrazole, and pyrazoline analogs of diarylpentanoids (excluding compounds 3a , 4a , 5a , and 5b ) was pan‐assay interference compounds‐filtered and synthesized via the reaction of diarylpentanoids with hydrazine monohydrate and phenylhydrazine. Each analog was evaluated for its anti‐inflammatory ability via the suppression of nitric oxide (NO) on IFN‐γ/LPS‐activated RAW264.7 macrophage cells. The compounds were also investigated for their inhibitory capability toward acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), using a modification of Ellman's spectrophotometric method. The most potent NO inhibitor was found to be phenylpyrazole analog 4c , followed by 4e , when compared with curcumin. In contrast, pyrazole 3a and pyrazoline 5a were found to be the most selective and effective BChE inhibitors over AChE. The data collected from the single‐crystal X‐ray diffraction analysis of compound 5a were then applied in a docking simulation to determine the potential binding interactions that were responsible for the anti‐BChE activity. The results obtained signify the potential of these pyrazole and pyrazoline scaffolds to be developed as therapeutic agents against inflammatory conditions and Alzheimer's disease.  相似文献   
992.
COVID-19 pandemic caused by SARS-CoV-2 infection severely threatens global health and economic development. No effective antiviral drug is currently available to treat COVID-19 and any other human coronavirus infections. We report herein that a macrolide antibiotic, carrimycin, potently inhibited the cytopathic effects (CPE) and reduced the levels of viral protein and RNA in multiple cell types infected by human coronavirus 229E, OC43, and SARS-CoV-2. Time-of-addition and pseudotype virus infection studies indicated that carrimycin inhibited one or multiple post-entry replication events of human coronavirus infection. In support of this notion, metabolic labelling studies showed that carrimycin significantly inhibited the synthesis of viral RNA. Our studies thus strongly suggest that carrimycin is an antiviral agent against a broad-spectrum of human coronaviruses and its therapeutic efficacy to COVID-19 is currently under clinical investigation.  相似文献   
993.
994.

Introduction and Hypothesis

The objective of this study was to identify the predictors of postoperative voiding dysfunction in women following extensive vaginal pelvic reconstructive surgery.

Methods

We enrolled 1,425 women who had pelvic organ prolapse of POP-Q stage III or IV and had undergone vaginal pelvic reconstructive surgery with or without transvaginal mesh insertion from January 2006 to December 2014. All subjects were required to complete a 72-h voiding diary, and the IIQ-7, UDI-6, POPDI-6 and PISQ-12 questionnaires. Urodynamic study was performed preoperatively and postoperatively.

Results

Of the 1,425 women, 54 were excluded due to incomplete data, and 1,017 of the remaining 1,371 (74.2 %) had transvaginal mesh surgery and 247 (18 %) had concurrent midurethral sling insertion. Of 380 women (27.7 %) with preoperative voiding dysfunction, 37 (9.7 %) continued to have voiding dysfunction postoperatively. Of the remaining 991 women (72.3 %) with normal preoperative voiding function, 11 (1.1 %) developed de novo voiding dysfunction postoperatively. The overall incidence of postoperative voiding dysfunction was 3.5 % (48/1,371). Those with concurrent midurethral sling insertion were at higher risk of developing voiding dysfunction postoperatively (OR 3.12, 95 % CI 1.79?–?5.46, p?<?0.001). Diabetes mellitus, preoperative detrusor pressure at maximal flow (Dmax) <10 cm H2O and postvoid residual volume ≥200 ml were significant risk factors for the development of postoperative voiding dysfunction (OR 3.07, 1.84 and 2.15, respectively; 95 % CI 1.69?–?5.60, 1.39?–?2.91 and 1.10?–?3.21, respectively).

Conclusions

Diabetes mellitus, concurrent midurethral sling insertion, preoperative Dmax <10 cm H2O and postvoid residual volume ≥200 ml in patients with advanced pelvic organ prolapse were risk factors for the development of postoperative voiding dysfunction after vaginal pelvic reconstructive surgery. Therefore, counseling is worthwhile before considering vaginal pelvic reconstructive surgery.
  相似文献   
995.
996.
Mast cells play an essential role in IgE‐FcεR1‐mediated allergic diseases. Citrus aurantium is a prolific source of flavonoids with various biological activities, including anti‐inflammatory, antioxidant, and anti‐tumor efficacies. Neohesperidin is a novel flavonoid isolated from the leaves of C. aurantium. In this study, the anti‐allergic and anti‐inflammatory potentials of neohesperidin were investigated along with its molecular mechanism. The anti‐anaphylactic activity of neohesperidin was evaluated through hind paw extravasation study in mice. Calcium imaging was used to assess intracellular Ca2+ mobilization. The levels of cytokines and chemokines were measured using enzyme immunoassay kits. Western blotting was used to explore the related molecular signaling pathways. Neohesperidin suppressed IgE‐induced mast cell activations, including degranulation and secretion of cytokines and eicosanoids through inhibiting phosphorylation of Lyn kinase. Neohesperidin inhibited the release of histamine and other proinflammatory cytokines through a mast cell‐dependent passive cutaneous anaphylaxis animal model. Histological studies demonstrated that neohesperidin substantially inhibited IgE‐induced cellular infiltration and attenuated mast cell activation in skin tissue. In conclusion, our study revealed that neohesperidin could inhibit allergic responses in vivo and in vitro, and the molecule may be regarded as a novel agent for preventing mast cell‐immediate and delayed allergic diseases.  相似文献   
997.
Introduction: Pancreatic cancer (PC) is characterized by mucin overexpression. MUC4 is the most differentially overexpressed membrane-bound mucin that plays a functional role in disease progression and therapy resistance.

Area covered: We describe the clinicopathological significance of MUC4, summarize mechanisms contributing to its deregulated expression, review preclinical studies aimed at inhibiting MUC4, and discuss how MUC4 overexpression provides opportunities for developing targeted therapies. Finally, we discuss the challenges for developing MUC4-based therapeutics, and identify areas where efforts should be directed to effectively exploit MUC4 as a therapeutic target for PC.

Expert opinion: Studies demonstrating that abrogation of MUC4 expression reduces proliferation and metastasis of PC cells and enhances sensitivity to therapeutic agents affirm its utility as a therapeutic target. Emerging evidence also supports the suitability of MUC4 as a potential immunotherapy target. However, these studies have been limited to in vitro, ex vivo or in vivo approaches using xenograft tumors in immunodeficient murine models. For translational relevance, MUC4-targeted therapies should be evaluated in murine models with intact immune system and accurate tumor microenvironment. Additionally, future studies evaluating MUC4 as a target for immunotherapy must entail characterization of immune response in PC patients and investigate its association with immunosuppression and survival.  相似文献   

998.
Context: Vernonia amygdalina Del. (VA) (Asteraceae) is commonly used to treat hypertension in Malaysia.

Objective: This study investigates the vasorelaxant mechanism of VA ethanol extract (VAE) and analyzes its tri-step FTIR spectroscopy fingerprint.

Materials and methods: Dried VA leaves were extracted with ethanol through maceration and concentrated using rotary evaporator before freeze-dried. The vasorelaxant activity and the underlying mechanisms of VAE using the cumulative concentration (0.01–2.55?mg/mL at 20-min intervals) were evaluated on aortic rings isolated from Sprague Dawley rats in the presence of antagonists.

Results: The tri-step FTIR spectroscopy showed that VAE contains alkaloids, flavonoids, and saponins. VAE caused the relaxation of pre-contracted aortic rings in the presence and absence of endothelium with EC50 of 0.057?±?0.006 and 0.430?±?0.196?mg/mL, respectively. In the presence of Nω-nitro-l-arginine methyl ester (EC50 0.971?±?0.459?mg/mL), methylene blue (EC50 1.203?±?0.426?mg/mL), indomethacin (EC50 2.128?±?1.218?mg/mL), atropine (EC50 0.470?±?0.325?mg/mL), and propranolol (EC50 0.314?±?0.032?mg/mL), relaxation stimulated by VAE was significantly reduced. VAE acted on potassium channels, with its vasorelaxation effects significantly reduced by tetraethylammonium, 4-aminopyridine, barium chloride, and glibenclamide (EC50 0.548?±?0.184, 0.158?±?0.012, 0.847?±?0.342, and 0.304?±?0.075?mg/mL, respectively). VAE was also found to be active in reducing Ca2+ released from the sarcoplasmic reticulum and blocking calcium channels.

Conclusions: The vasorelaxation effect of VAE involves upregulation of NO/cGMP and PGI2 signalling pathways, and modulation of calcium/potassium channels, and muscarinic and β2-adrenergic receptor levels.  相似文献   
999.
1000.
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