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171.
Janette Smith Penelope Moyle Helen Addley Susan Freeman 《Obstetrics, Gynaecology and Reproductive Medicine》2018,28(8):229-236
Radiology continues to play an essential role in the management of benign gynaecological conditions. Multiple imaging modalities are utilised to investigate benign conditions: ultrasound; computed tomography and magnetic resonance imaging. Each modality has a different role in diagnosis, treatment selection and follow-up. This review discusses the different imaging modalities and their recommended roles in the imaging benign gynaecological conditions. The imaging findings of common benign female pelvic pathology are discussed and illustrated. 相似文献
172.
目的探讨1.5T磁共振T2 mapping成像在腰椎间盘退行性变之中的诊断价值。方法选择2018年1月—2019年1月在本院行1.5T磁共振检查的50例腰背疼痛患者当做研究对象,所有患者均进行矢状位T1WI、T2WI、横断位T2WI、正中矢状位T2 mapping成像。以Pfirrmann标准作为依据,进行腰椎间盘分级,并对髓核、纤维环前缘和后缘T2值进行测量,分别对各级髓核及纤维环的前缘及后缘T2值进行对比,并对T2值、分级以及年龄之间的相关性进行分析,同时,选择15例患者时隔6个月进行第2次磁共振检查,对两次椎间盘T2值之间产生的差异进行对比。结果腰椎间盘各级髓核T2值中,Ⅳ级与Ⅴ级之间未见明显差异,无统计学意义,P>0.05,其余各级间均存在明显差异,有统计学意义,P<0.05;患者年龄与分级呈正相关,年龄与T2值呈负相关,T2值与分级呈负相关;15例患者前后两次检测中,椎间盘纤维环前缘、后缘、髓核T2值均不存在明显差异,无统计学意义,P>0.05。结论腰椎间盘退行性变采用1.5T磁共振T2 mapping成像进行检查,能够实现有效的定量评估,特别是髓核T2值可对Ⅰ~Ⅳ级椎间盘退行性变程度差异进行有效反映,值得应用。 相似文献
173.
目的本研究拟运用MRI三维动脉自选标记法(3D-ASL),结合DWI及时间飞跃法MRA(3DTOF-MRA),探讨3D-ASL在TIA的诊断、血流灌注评估等方面的应用价值,为临床超早期诊断、治疗提供更多的理论依据。方法发病24 h内的TIA患者13例,入院时进行常规MRI、DWI、3D-TOF-MRA及3D-ASL扫描。观察所有患者MRA图,分析颅内血管及颈内动脉有无狭窄及异常,比较DWI所示梗死面积(SDWI)和全脑血流量(CBF)图上灌注异常面积(SASL)的差异,分别计算DWI和3D-ASL对TIA患者的检出率,并结合MRA分析造成脑组织血流灌注异常的原因。对于DWI阴性但ASL灌注异常,且MRA(或CTA)显示血管狭窄的患者,计算病灶侧和对侧相应区域的CBF值的比值(rCBF),比较rCBF与入院时(发病24 h内)的NIHSS、Glasgow昏迷评分量表(GCS)、mRS及神经内科临床评分量表(ABCD2)评分、患者发病时间以及一过性脑缺血症状发作持续时间有无相关性,并且比较分析rCBF值与MRA(或CTA)所示血管直径狭窄程度的相关性。结果(1)SASL>SDWI:13例TIA患者中,11例DWI未发现病灶,即SDWI=0,而SASL>0,且显示灌注减低;2例DWI阳性,但病灶面积仍SASL>SDWI。(2)3D-ASL对TIA的检出率明显高于DWI:DWI对TIA患者病灶的检出率为15%;3D-ASL对TIA患者病灶的检出率为69%。(3)rCBF与入院时(发病24 h内)的NIHSS、GCS、mRS及ABCD2评分的分值均无相关性;rCBF与患者发病时间及一过性脑缺血症状发作持续时间无相关性;rCBF值与MRA(或CTA)所示血管直径狭窄程度呈负相关关系(rs=-0.697,P=0.011)。结论3DASL与DWI相比,对TIA的诊断敏感性较高。及早行3D-ASL检查,并与DWI、MRA等序列联合应用,能更早发现灌注异常,并初步提示责任血管狭窄程度,为临床治疗提供科学依据。 相似文献
174.
《Clinical microbiology and infection》2019,21(6):659-666
ObjectivesVaccination for dengue with the live attenuated tetravalent CYD-TDV vaccine (Dengvaxia®) is only recommended in individuals who have had prior dengue virus (DENV) infection. Rapid diagnostic tests (RDT) for past DENV infection would offer a convenient method for pre-vaccination screening at point-of-care. A systematic review was conducted to evaluate the performance of current dengue RDTs for determining dengue serostatus, using IgG antibodies against DENV as a marker of past infection.MethodsPubMed and EMBASE databases were searched from 2000 to 2018 to identify studies evaluating dengue RDTs in individuals with known or possible previous DENV infection. Study quality was evaluated using GRADE and QUADAS-2 criteria. Semi-structured interviews were also performed with available dengue RDT manufacturers.ResultsThe performance of four dengue IgG RDTs was determined in 3137 individuals across ten studies conducted in 13 countries, with serum used in most of the studies. No studies reported data for determining dengue serostatus, and limited data were available regarding cross-reactivity with other viruses. The majority of studies demonstrated sensitivities and specificities between 80% and 100% for dengue IgG detection in samples from secondary infection or convalescent time-points after recent infection.ConclusionsAlthough current dengue IgG RDTs have shown reasonable performance compared with laboratory-based tests in secondary infection, additional research is needed to determine how RDTs would perform in relevant populations targeted for vaccination. New RDTs or modifications to current RDTs are feasible and may optimize the performance of these tests for use in a pre-vaccination screening approach. 相似文献
175.
Human leukocyte antigen typing using buccal swabs as accurate and non‐invasive substitute for venipuncture in children at risk for celiac disease 下载免费PDF全文
176.
Evaluation of Resistance Assays Trial Investigators MRC Clinical Trials Unit London United Kingdom 《HIV clinical trials》2013,14(4):183-186
AbstractPurpose: To assess the clinical utility of genotypic resistance testing among HIV-1-infected patients with limited prior exposure to antiretroviral drugs. Method: Patients experiencing virological failure were randomly allocated to either centralized genotypic resistance testing or to no testing and were followed for a minimum of 1 year. Results: 55 patients were recruited from 14 centers in the United Kingdom. There were no demonstrable differences between the groups in terms of virological or immunological response. For patients allocated to resistance testing, there was an increased tendency to recycle previously used drugs. Conclusion: The study did not demonstrate a benefit of genotypic resistance testing in this population, although statistical power was low. However, testing did alter prescribing behavior, and clinical effects may become manifest in the longer term. 相似文献
177.
Physician's appraisal vs documented signs and symptoms in the interpretation of food challenge tests: The EuroPrevall birth cohort 下载免费PDF全文
Linus B. Grabenhenrich Andreas Reich Doreen McBride Aline Sprikkelman Graham Roberts Kate E. C. Grimshaw Alessandro G. Fiocchi Photini Saxoni‐Papageorgiou Nikolaos G. Papadopoulos Ana Fiandor Santiago Quirce Marek L. Kowalski Sigurveig T. Sigurdardottir Ruta Dubakiene Jonathan O. B. Hourihane Leonard Rosenfeld Bodo Niggemann Thomas Keil Kirsten Beyer 《Pediatric allergy and immunology》2018,29(1):58-65
178.
The performance of a diagnostic test is best evaluated against a reference test that is without error. For many diseases, this is not possible, and an imperfect reference test must be used. However, diagnostic accuracy estimates may be biased if inaccurately verified status is used as the truth. Statistical models have been developed to handle this situation by treating disease as a latent variable. In this paper, we conduct a systematized review of statistical methods using latent class models for estimating test accuracy and disease prevalence in the absence of complete verification. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
179.
180.