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Ameloblastic fibroma of the jaw is a rare, benign mixed odontogenic tumor, having little tendency for local invasion and a low recurrence rate. Cytologic distinction from ameloblastoma, ameloblastic fibrosarcoma, and intraosseous adenoid cystic carcinoma is necessary, in view of the different biologic behavior. A painful, slow-growing swelling of the jaw in a 5-yr-old child clinicoradiologically considered as a benign cystic lesion was aspirated. Sheets of small monomorphic epithelial cells with peripheral palisading by columnar cells were seen on cytology smears. The striking feature was central hyaline globules in some tubules. A cytologic possibility of adenomatoid odontogenic tumor was suggested. Histopathology, however, confirmed it to be an ameloblastic fibroma.  相似文献   
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Carcinoma of the oral cavity constitutes approximately 40% of overall malignant tumours in India, with an incidence of about 56,000 cases per year. Radiation responses in oral cancer cells by cytology have not been extensively studied. 102 patients with squamous cell carcinoma of the oral cavity treated by fractionated radiotherapy were studied. Serial scrape smears were taken from each tumour before and after irradiation. The abnormal nuclear counts per 1000 malignant cells were 1.6 and 14.1(p<0.001) for micronucleation, 0.9 and 5.5 (p<0.001) for nuclear budding, 7.6 and 28.1(p<0.001) for binucleation and 2.4 and 11.7(p<0.001) for multinucleation respectively. The study showed a significant rise in radiation induced cytological responses. In addition, radiation changes observed included abnormal and incomplete divisions of a nucleus, fibroblast like appearance cells, and enlargement of nuclear size as well as cytoplasmic granulation. These changes may have an important role to play in understanding the mechanism of cell killing after radiotherapy.  相似文献   
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Cancer therapy is a fast-emerging biomedical paradigm that elevates the diagnostic and therapeutic potential of a nanovector for identification, monitoring, targeting, and post-treatment response analysis. Nanovectors of superparamagnetic iron oxide nanoparticles (SPION) are of tremendous significance in cancer therapy because of their inherited high surface area, high reactivity, biocompatibility, superior contrast, and magnetic and photo-inducibility properties. In addition to a brief introduction, we summarize various progressive aspects of nanomagnets pertaining to their production with an emphasis on sustainable biomimetic approaches. Post-synthesis particulate and surface alterations in terms of pharmaco-affinity, liquid accessibility, and biocompatibility to facilitate cancer therapy are highlighted. SPION parameters including particle contrast, core-fusions, surface area, reactivity, photosensitivity, photodynamics, and photothermal properties, which facilitate diverse cancer diagnostics, are discussed. We also elaborate on the concept of magnetism to selectively focus chemotherapeutics on tumors, cell sorting, purification of bioentities, and elimination of toxins. Finally, while addressing the toxicity of nanomaterials, the advent of ultrasmall nanomagnets as a healthier alternative with superior properties and compatible cellular interactions is reviewed. In summary, these discussions spotlight the versatility and integration of multi-tasking nanomagnets and ultrasmall nanomagnets for diverse cancer theragnostics.  相似文献   
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BackgroundIn the current study, we examined the real-world prevalence of highly pigmented advanced melanomas (HPMel) and the clinicopathologic, genomic, and ICPI biomarker signatures of this class of tumors.Materials and MethodsOur case archive of clinical melanoma samples for which the ordering physician requested testing for both PD-L1 immunohistochemistry (IHC) and comprehensive genomic profiling (CGP) was screened for HPMel cases, as well as for non-pigmented or lightly pigmented advanced melanoma cases (LPMel).ResultsOf the 1268 consecutive melanoma biopsies in our archive that had been submitted for PD-L1 IHC, 13.0% (165/1268) were HPMel and 87.0% (1103/1268) were LPMel. In the HPMel cohort, we saw a significantly lower tumor mutational burden (TMB, median 8.8 mutations/Mb) than in the LPMel group (11.4 mut/Mb), although there was substantial overlap. In examining characteristic secondary genomic alterations (GA), we found that the frequencies of GA in TERTp, CDKN2A, TP53, and PTEN were significantly lower in the HPMel cases than in LPMel. A higher rate of GA in CTNNB1, APC, PRKAR1A, and KIT was identified in the HPMel cohort compared with LPMel.ConclusionsIn this study, we quantified the failure rates of melanoma samples for PD-L1 testing due to high melanin pigmentation and showed that CGP can be used in these patients to identify biomarkers that can guide treatment decisions for HPMel patients. Using this practical clinical definition for tumor pigmentation, our results indicate that HPMel are frequent at 13% of melanoma samples, and in general appear molecularly less developed, with a lower TMB and less frequent secondary GA of melanoma progression.  相似文献   
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The biological connections between psoriasis and diabetes have been suggested by epidemiological, immunological and genetic studies. To identify additional shared susceptibility loci and investigate shared pathogenesis between these two diseases, we genotyped 89 reported diabetes susceptibility loci in 4456 psoriasis cases and 6027 controls of Chinese population using the MassARRAY system from Sequenom. We discovered three significant associations at rs6679677 on 1p13.2 (P=6.15×10?5, OR=5.07), rs16861329 on 3q27.3 (P=2.02×10?4, OR=0.87) and rs849135 on 7p15.1 (P=6.59×10?9, OR=1.78), which suggested PTPN22, ST6GAL1 and JAZF1 as novel susceptibility genes for psoriasis in Chinese population. Our findings implicated the involvement of T‐cell receptor signalling pathway in the pathogenesis of psoriasis and further confirmed the shared genetic susceptibility between psoriasis and diabetes.  相似文献   
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Melatonin has demonstrated a potential protective effect in central nervous system. Thus, it is interesting to determine whether pre‐ischemia melatonin administration could protect against cerebral ischemia/reperfusion (IR)‐related injury and the underlying molecular mechanisms. In this study, we revealed that IR injury significantly activated endoplasmic reticulum (ER) stress and autophagy in a middle cerebral artery occlusion mouse model. Pre‐ischemia melatonin treatment was able to attenuate IR‐induced ER stress and autophagy. In addition, with tandem RFP‐GFP‐LC3 adeno‐associated virus, we demonstrated pre‐ischemic melatonin significantly alleviated IR‐induced autophagic flux. Furthermore, we showed that IR induced neuronal apoptosis through ER stress related signalings. Moreover, IR‐induced autophagy was significantly blocked by ER stress inhibitor (4‐PBA), as well as ER‐related signaling inhibitors (PERK inhibitor, GSK; IRE1 inhibitor, 3,5‐dibromosalicylaldehyde). Finally, we revealed that melatonin significantly alleviated cerebral infarction, brain edema, neuronal apoptosis, and neurological deficiency, which were remarkably abolished by tunicamycin (ER stress activator) and rapamycin (autophagy activator), respectively. In summary, our study provides strong evidence that pre‐ischemia melatonin administration significantly protects against cerebral IR injury through inhibiting ER stress‐dependent autophagy. Our findings shed light on the novel preventive and therapeutic strategy of daily administration of melatonin, especially among the population with high risk of cerebral ischemic stroke.  相似文献   
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