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Die Diabetologie - Deutschland ist ein Einwanderungsland und 2019 hatte mehr als jede vierte hier lebende Person einen sog. Migrationshintergrund. Bei dieser statistisch definierten Gruppe handelt...  相似文献   
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Anabolic‐androgenic steroids are synthetic compounds prohibited due to their performance‐enhancing characteristics. The use of these substances is known to cause health‐related issues, which highlights the importance of being able to evaluate the scale of consumption by the general population. However, most available research on the analysis of anabolic steroids is focused on animals and athletes in connection with doping. The potential of wastewater‐based epidemiology as an intelligence tool for the assessment of community level use of anabolic steroids is presented herein. A liquid chromatography tandem mass spectrometry method was developed for the analysis of 10 anabolic‐androgenic steroids and 14 endogenous hormones in influent wastewater. The validated method was applied to sixteen 24‐hour composite wastewater influent samples that were collected over a period of five years from two wastewater treatment plants in Queensland, Australia. Nine investigated compounds were found to be present at concentrations between 14 and 611 ng L?1 which translated into 3–104 mg excreted per 1000 individuals per day. It was concluded that the developed analytical method is suitable for the analysis of AAS in wastewater matrix. Additionally, both the inclusion of metabolites and further investigation into deconjugation by enzymatic hydrolysis would aid in understanding and evaluating community anabolic steroid use. For the first time, this study presents the application of wastewater‐based epidemiology on anabolic‐androgenic steroids in Australia.  相似文献   
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AIM: To evaluate the diagnostic yield(inflammatory activity) and efficiency(size of the biopsy specimen) of SpyGlassTM-guided biopsy vs standard brush cytology in patients with and without primary sclerosing cholangitis(PSC).METHODS: At the University Medical Center Mainz, Germany, 35 consecutive patients with unclear biliarylesions(16 patients) or long-standing PSC(19 patients) were screened for the study. All patients underwent a physical examination, lab analyses, and abdominal ultrasound. Thirty-one patients with non-PSC strictures or with PSC were scheduled to undergo endoscopic retrograde cholangiography(ERC) and subsequent per-oral cholangioscopy(POC). Standard ERC was initially performed, and any lesions or strictures were localized. POC was performed later during the same session. The Boston Scientific SpyGlass SystemTM(Natick, MA, United States) was used for choledochoscopy. The biliary tree was visualized, and suspected lesions or strictures were biopsied, followed by brush cytology of the same area. The study endpoints(for both techniques) were the degree of inflammation, tissue specimen size, and the patient populations(PSC vs non-PSC). Inflammatory changes were divided into three categories: none, low activity, and high activity. The specimen quantity was rated as low, moderate, or sufficient.RESULTS: SpyGlassTM imaging and brush cytology with material retrieval were performed in 29 of 31(93.5%) patients(23 of the 29 patients were male). The median patient age was 45 years(min, 20 years; max, 76 years). Nineteen patients had known PSC, and 10 showed non-PSC strictures. No procedure-related complications were encountered. However, for both methods, tissues could only be retrieved from 29 pa-tients. In cases of inflammation of the biliary tract, the diagnostic yield of the SpyGlassTM-directed biopsies was greater than that using brush cytology. More tissue material was obtained for the biopsy method than for the brush cytology method(P = 0.021). The biopsies showed significantly more inflammatory characteristics and greater inflammatory activity compared to the cy-tological investigation(P = 0.014). The greater quantity of tissue samples proved useful for both PSC and non-PSC patients.CONCLUSION: SpyGlassTM imaging can be recom-mended for proper inflammatory diagnosis in PSC pa-tients. However, its value in diagnosing dysplasia wasnot addressed in this study and requires further investi-gation.  相似文献   
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The recent success of antibody–drug conjugates (ADCs) in the treatment of cancer has led to a revived interest in microtubule-destabilizing agents. Here, we determined the high-resolution crystal structure of the complex between tubulin and maytansine, which is part of an ADC that is approved by the US Food and Drug Administration (FDA) for the treatment of advanced breast cancer. We found that the drug binds to a site on β-tubulin that is distinct from the vinca domain and that blocks the formation of longitudinal tubulin interactions in microtubules. We also solved crystal structures of tubulin in complex with both a variant of rhizoxin and the phase 1 drug PM060184. Consistent with biochemical and mutagenesis data, we found that the two compounds bound to the same site as maytansine and that the structures revealed a common pharmacophore for the three ligands. Our results delineate a distinct molecular mechanism of action for the inhibition of microtubule assembly by clinically relevant agents. They further provide a structural basis for the rational design of potent microtubule-destabilizing agents, thus opening opportunities for the development of next-generation ADCs for the treatment of cancer.Microtubule-targeting agents such as the taxanes and the vinca alkaloids represent a successful class of anticancer drugs (1). Vinblastine, for example, is a microtubule-destabilizing agent (MDA) that is widely used in combination therapy for the treatment of childhood and adult malignancies (2). The broad clinical application of MDAs, however, is hampered by their severe adverse effects (3). This problem has been very recently addressed by the use of antibody–drug conjugate (ADC) approaches, which have revived interest in the development of highly potent MDAs for therapeutic use (46).For several important MDAs, the molecular mechanism of action on tubulin and microtubules has so far remained elusive. Rhizoxin, for example, is a potent MDA that has been investigated in phase 2 clinical trials, but for reasons poorly understood, it has demonstrated only very limited clinical efficacy (7). At the molecular level, it is well established that rhizoxin interferes with the binding of vinblastine to tubulin; however, the exact location of its binding site has been a matter of debate (810). Interestingly, biochemical and mutagenesis data suggest that the structurally unrelated MDA maytansine (9, 11), which is part of an ADC that was recently approved by the FDA for the treatment of advanced breast cancer (11, 12), and the phase 1 drug PM060184 (13, 14) (Fig. 1A) share a common tubulin-binding site with rhizoxin (9, 13, 14). These two latter drugs have also been reported to interfere with the binding of vinblastine; however, as for rhizoxin, the exact binding sites and modes of action of maytansine and PM060184 have not been elucidated (9, 1416).Open in a separate windowFig. 1.Structure of the tubulin–rhizoxin F complex. (A) Chemical structures of rhizoxin F, maytansine, and PM060184. (B) Overall view of the T2R-TTL–rhizoxin F complex. Tubulin (gray), RB3 (light green), and TTL (violet) are shown in ribbon representation; the MDA rhizoxin F (orange) and GDP (cyan) are depicted in spheres representation. As a reference, the vinblastine structure (yellow, PDB ID no. 1Z2B) is superimposed onto the T2R complex. (C) Overall view of the tubulin–rhizoxin F interaction in two different orientations. The tubulin dimer with bound ligand (α-tubulin-2 and β-tubulin-2 of the T2R-TTL–rhizoxin F complex) is shown in surface representation. The vinblastine structure is superimposed onto the β-tubulin chain to highlight the distinct binding site of rhizoxin F. All ligands are in sphere representation and are colored in orange (rhizoxin F), cyan (GDP), and yellow (vinblastine). (D) Close-up view of the interaction observed between rhizoxin F (orange sticks) and β-tubulin (gray ribbon). Interacting residues of β-tubulin are shown in stick representation and are labeled.To establish the exact tubulin-binding site of rhizoxin, maytansine, and PM060184 and to clarify their specific interactions with the protein, we have investigated the structures of the corresponding ligand–tubulin complexes by X-ray crystallography. Our data reveal a new tubulin-binding site and pharmacophore for small molecules, and binding to this site is associated with a distinct molecular mechanism for the inhibition of microtubule formation.  相似文献   
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