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991.
X-Y. Duan W. Wang M. Li Y. Li Y-M. Guo 《Brazilian journal of medical and biological research》2015,48(3):267-272
18F-fluoro-2-deoxyglucose (FDG) positron emission tomography
(PET)/computed tomography (CT) is widely used to diagnose and stage non-small cell
lung cancer (NSCLC). The aim of this retrospective study was to evaluate the
predictive ability of different FDG standardized uptake values (SUVs) in 74 patients
with newly diagnosed NSCLC. 18F-FDG PET/CT scans were performed and
different SUV parameters (SUVmax, SUVavg, SUVT/L,
and SUVT/A) obtained, and their relationship with clinical characteristics
were investigated. Meanwhile, correlation and multiple stepwise regression analyses
were performed to determine the primary predictor of SUVs for NSCLC. Age, gender, and
tumor size significantly affected SUV parameters. The mean SUVs of squamous cell
carcinoma were higher than those of adenocarcinoma. Poorly differentiated tumors
exhibited higher SUVs than well-differentiated ones. Further analyses based on the
pathologic type revealed that the SUVmax, SUVavg, and
SUVT/L of poorly differentiated adenocarcinoma tumors were higher than
those of moderately or well-differentiated tumors. Among these four SUV parameters,
SUVT/L was the primary predictor for tumor differentiation. However, in
adenocarcinoma, SUVmax was the determining factor for tumor
differentiation. Our results showed that these four SUV parameters had predictive
significance related to NSCLC tumor differentiation; SUVT/L appeared to be
most useful overall, but SUVmax was the best index for adenocarcinoma
tumor differentiation. 相似文献
992.
《Biomaterials》2015
Mesoporous silica nanoparticles (MSNs) can provide a structural foundation for a new generation of nanocarriers with a broad range of functionalities. Multifunctional MSNs can serve as all-in-one diagnostic and therapeutic tools that can be used to simultaneously visualize and treat various diseases, such as cancer. This research study is the first time that two lanthanide-based imaging systems have been combined to incorporate controlled drug release and targeted tracing into a single MSN-based nano-platform for a novel theranostic drug delivery system. Doping lanthanide ions, i.e., europium (Eu) and gadolinium (Gd) ions, into an MSN structure (EuGd-MSNs) imparts fluorescence and magnetism to the nanostructure that can be used to develop magnetic resonance imaging (MRI) and biological fluorescence tools. Current cancer research has revealed that most human cancer cells express a large number of folate receptors on their surface. Grafting folic acid (FA) onto the EuGd-MSN surface (EuGd-FA-MSNs) imparts a targeting function to the MSN because of the specificity of the binding of FA to cell surface receptors. Furthermore, grafting anticancer drugs, such as camptothecin (CPT), onto the surface of these MSNs by forming disulfide bonds (EuGd-SS-CPT-FA-MSNs) enables intracellular controlled drug release. A high concentration of intracellular glutathione cleaves the disulfide bond to release the drug and treat the disease. The results of in vitro and in vivo studies show that the functionalized MSNs can be successfully used as a platform to integrate dual-imaging, targeting, and therapeutic treatment in multifunctional diagnosis drug delivery systems. 相似文献
993.
994.
Human papillomavirus infection in the oromaxillofacial area: Clinical anatomy and histological considerations 下载免费PDF全文
Aranka Ilea Bianca Boşca Viorel MiclĂuş Vasile Rus Anida Maria BĂbţan Radu Septimiu CÂmpian 《Clinical anatomy (New York, N.Y.)》2015,28(8):1002-1007
Clinical manifestations of human papillomavirus (HPV) infection in the head and neck can range from benign lesions, which are the most frequent, to malignant lesions. The prevalence of head and neck cancer is increasing, despite currently decreasing trends in known risk factors such as smoking and alcohol use. A new patient profile has appeared in recent practice: most frequently a middle‐aged male patient who does not smoke or drink alcohol, is sexually active (possibly having multiple partners), and presents with oral or cervicofacial lesions requiring diagnosis and treatment. Another risk factor that should be considered in these patients is HPV infection. The association of oral potentially malignant disorders (OPMD) with HPV is a challenge for the medical practitioner. The gold standard for diagnosis is histopathological examination, which can also yield evidence suggesting HPV infection. Determination of the viral genotype provides additional data for assessing the oncological risk of an HPV infection. Treatment of these patients is aimed at removing the lesions, in association or not with antiviral treatment and recurrence control. Clin. Anat. 28:1002–1007, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
995.
996.
Interstitial cystitis (IC) is a heterogeneous chronic disease of unknown etiology that impacts a very large number of women. Symptoms are highly variable: patients may suffer from pelvic pain that is exacerbated by bladder filling, and can be associated with a variety of lower urinary tract symptoms including frequency and urgency. Given the varying presentations and severities of corresponding treatment must be tailored to each specific patient. Current American Urological Association (AUA) guidelines separate the IC treatment recommendations into six tiers of increasing invasive therapies. These treatment guidelines begin with education and lifestyle modifications and progress through levels of physical, pharmacological, and ultimately surgical therapies for those that fail the less invasive therapies. The purpose of this review is to outline the recommendations for the treatment of IC and the evidence from which these recommendations arise. Furthermore, we examine the most up to date literature so that we may recognize future directions in the treatment of IC. 相似文献
997.
ObjectiveOur aim was to study photodecomposition, photomutagenicity and cytotoxicity of retinyl palmitate (RP), a principal storage form of vitamin A in humans and animals, under He–Ne laser photoirradiation. Moreover, the effect of different concentrations and timing protocol of antioxidants on photodynamic therapy (PDT) is contradictory, so the effect of RP (as antioxidant) on the PDT cytotoxicity was studied.MethodsPhotomutagenicity was tested by Ames test. Photodecomposition was studied by UV–vis spectroscopy. Cytotoxicity was measured with MTT-assay. Moreover, the effect of PDT, using hematoporphyrin derivatives (HpD) as photosensitizer under He–Ne laser irradiation (10 J/cm2), was studied on HeLa cells either with or without RP (1–100 μM) which incubated with the cells for short or long incubation period (1 h or 24 h) prior to PDT.ResultsNo photodecomposition of RP alone was obseved whereas there is a little photodecomposition of RP only in presence of HpD under irradiation with He–Ne laser. Moreover, no photomutagenicity was observed in Salmonella typhimurium strains under laser irradiation in presence or absence of HpD. RP alone (1–100 μM) significantly decrease the viability of HeLa cells. Laser irradiation of HeLa cells pre-incubated with RP alone for 24 h showed further significant decrease in viability of the cells. While RP incubations for 1 h before PDT had slight effect on the cells, 24 h incubation before PDT enhanced the cytotoxicity of PDT on HeLa cells.ConclusionsRP can be used 24 h before PDT to enhance its effects. RP is not mutagenic under irradiation with He–Ne laser. 相似文献
998.
目的探讨胺碘酮联合美托洛尔治疗老年冠心病的临床效果。方法将我院于2013年1月~2014年1月收治的156例老年冠心病患者列为研究对象,将其随机平分,观察组给予常规药物加胺碘酮联合美托洛尔口服;对照组给予常规药物加胺碘酮口服,6个月后对较分析其心绞痛、心律失常的改善情况。结果观察组室性心绞痛、心律失常的治疗有效率均明显大于对照组,差异显著(P0.05),具有统计学意义。结论胺碘酮联合美托洛尔治疗老年冠心病效果比单用胺碘酮疗效好,差异显著。 相似文献
999.
《Revista brasileira de otorrinolaringologia (English ed.)》2015,81(5):541-548
IntroductionAn ongoing discussion is found in medical literature about the reasons for changes in thyroid carcinoma incidence patterns over the last decades.ObjectiveTo analyze the clinical and pathological characteristics of thyroid carcinoma cases over a decade.MethodsCross-sectional study over an historical cohort. Medical records of 628 thyroid cancer cases in a single center were reviewed. 597 patients were included. Microcarcinoma cases were selected for a qualitative analysis phase, in which medical records were reviewed for better understanding of thyroid nodule and thyroid cancer diagnosis process.ResultsAn increase in the proportion of cases with thyroid cancer diagnosis was observed throughout the decade; new cases were predominantly tumors of less than 2 cm, with histopathological signs of low aggressiveness. There was an increase in proportion of cases with malignant cytological results among microcarcinomas.ConclusionThere is a trend for increase in thyroidectomies due to cancer in this institution, with proportional increment of cases with histopathological characteristics indicative of early disease. Among microcarcinomas, there is an increasing group represented by cancer cases that were not incidentally diagnosed, related to an enhancement in preoperative diagnostic methods. 相似文献
1000.