全文获取类型
收费全文 | 6833篇 |
免费 | 453篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 93篇 |
妇产科学 | 66篇 |
基础医学 | 310篇 |
口腔科学 | 103篇 |
临床医学 | 481篇 |
内科学 | 786篇 |
皮肤病学 | 48篇 |
神经病学 | 332篇 |
特种医学 | 199篇 |
外科学 | 320篇 |
综合类 | 796篇 |
预防医学 | 3305篇 |
眼科学 | 31篇 |
药学 | 316篇 |
9篇 | |
中国医学 | 26篇 |
肿瘤学 | 94篇 |
出版年
2023年 | 171篇 |
2022年 | 297篇 |
2021年 | 396篇 |
2020年 | 385篇 |
2019年 | 497篇 |
2018年 | 392篇 |
2017年 | 290篇 |
2016年 | 200篇 |
2015年 | 222篇 |
2014年 | 559篇 |
2013年 | 470篇 |
2012年 | 546篇 |
2011年 | 526篇 |
2010年 | 355篇 |
2009年 | 359篇 |
2008年 | 306篇 |
2007年 | 283篇 |
2006年 | 218篇 |
2005年 | 134篇 |
2004年 | 119篇 |
2003年 | 85篇 |
2002年 | 50篇 |
2001年 | 41篇 |
2000年 | 30篇 |
1999年 | 23篇 |
1998年 | 18篇 |
1997年 | 12篇 |
1996年 | 10篇 |
1995年 | 14篇 |
1994年 | 14篇 |
1993年 | 9篇 |
1992年 | 10篇 |
1991年 | 4篇 |
1990年 | 7篇 |
1988年 | 4篇 |
1986年 | 2篇 |
1985年 | 19篇 |
1984年 | 27篇 |
1983年 | 19篇 |
1982年 | 26篇 |
1981年 | 24篇 |
1980年 | 15篇 |
1979年 | 24篇 |
1978年 | 23篇 |
1977年 | 27篇 |
1976年 | 18篇 |
1975年 | 12篇 |
1974年 | 20篇 |
1973年 | 14篇 |
1972年 | 1篇 |
排序方式: 共有7330条查询结果,搜索用时 15 毫秒
1.
2.
《Journal of vascular and interventional radiology : JVIR》2022,33(12):1531-1535
This study investigated the role of dual-energy computed tomography (CT) for lesion characterization in patients with peripheral arterial disease manifesting with chronic total occlusions (CTOs). Forty-one symptomatic patients with CTOs underwent dual-energy CT angiography before endovascular treatment. The lesions were subsequently analyzed in a dedicated workstation, and 2 indexes—dual-energy index (DEI) and effective Z (Zeff)—were calculated, ranging from 0.0027 to 0.321 and from 6.89 to 13.02, respectively. Statistical analysis showed a significant correlation between the DEI and Zeff values (P < .001). The interobserver intraclass correlation coefficient was 0.91 for the mean Zeff values and 0.86 for the mean DEI values. This technique could potentially provide useful information regarding the composition of a CTO. 相似文献
3.
《Journal of vascular and interventional radiology : JVIR》2022,33(5):518-524.e3
PurposeTo compare the characteristics of polidocanol (POL) and ethanolamine oleate (EO) sclerosing foams produced by a Shirasu porous glass membrane (SPGM) device with those made using a 3-way stopcock (3WSC).Materials and MethodsFoam half-life times were measured in an ex-vivo benchtop study. Computed tomography (CT) images of each foam were obtained over the time course, and a CT texture analysis was conducted. The bubble size in each foam was measured by an optical microscope.ResultsMedian foam half-life times were longer in the SPGM group than in the 3WSC group (POL: 198 vs 166 s, P = .02; EO: 640 vs 391 s, P < .01). In the CT texture analysis, median standard deviation (SD) and entropy (randomness) were lower, and median energy (uniformity) and gray-level cooccurrence matrix (GLCM) homogeneity were higher in the SPGM group than in the 3WSC group (POL SD: at 30 s and 50–300 s; POL entropy: at 0–60 s; EO SD: at 0–600 s; EO entropy: at 0–460 s; POL energy: at 0–40 s; POL GLCM homogeneity: at 0–250 s; EO energy: at 0–360 s; EO GLCM homogeneity: at 0–480 s; all P < .05). Median bubble diameters in the SPGM group and in the 3WSC group were 69 and 83 μm (P < .01), respectively, in the POL foam; and 36 and 36 μm (P = .45), respectively, in the EO foam.ConclusionsPOL and EO foams had greater uniformity and longer foam half-life time when prepared with an SPGM device than with a 3WSC. 相似文献
4.
《Vaccine》2022,40(12):1855-1863
Renewed COVID-19 outbreaks, stemming from the highly infectious Delta and Omicron variants, prompted rising fears of a ‘pandemic among the unvaccinated’. To address this prevalent vaccination crisis, media framing communication strategies can amplify the scientific evidence on COVID-19 vaccines to reach diverse geographic and socio-economic communities. The critical role of media framing strategies to engage and encourage large populations regarding vaccine acceptance has been rarely studied, despite growing evidence on vaccine hesitancy. The present study used a multi-method approach (i.e., content analysis and quasi-experiments) that unpacked the framing practices employed by the mainstream media in Pakistan. The findings of the content analysis revealed that the media extensively used uncertainty, conflict, consequences, and action rather than new evidence and reassurance frames in its COVID-19 related campaigns. In a series of quasi-experiments involving 720 participants, we manipulated these six frames of COVID-19 related news coverage (i.e., uncertainty, conflict, consequences, action, new evidence, and reassurance) to investigate the underlying mechanism that influences vaccine acceptance. The findings established that the message-consistent effects of media frames manifesting fear (e.g., consequence and uncertainty) and action cues made receivers more supportive of vaccination. The present study findings theoretically address the calls for a more inclusive “community-health reporting model”, besides offering new evidence on the media framing strategies to deliver more targeted, meaningful, and effective campaigns to raise public acceptance for COVID-19 vaccines. 相似文献
5.
6.
7.
背景国家基本公共卫生服务项目的开展是我国新医改的重要举措,自2009年国家基本公共卫生服务项目开展后,其服务经费与服务项目不断扩增,由于涉及指标较多,覆盖面较广,探寻科学、客观、全面的基本公共卫生服务综合评价方法十分必要。目的探索适宜的基本公共卫生服务质量综合评价方法,通过质量评价为调整相关政策和提高服务质量提供依据。方法2019年2—4月,采用多阶段立意抽样方式从Z省南部、中部和北部地区共选取24家社区卫生服务中心(乡镇卫生院)作为评价对象,记为机构A~X。采用逼近理想解排序法(TOPSIS法)、秩和比法及二者模糊联合的方法对24家社区卫生服务中心(乡镇卫生院)2018年基层医疗卫生机构基本公共卫生服务质量进行综合评价(参考2018年国家基本公共卫生服务项目选取12项评价指标)。结果在TOPSIS法评价中,Ci值排名前三名的为A(0.917 4)、C(0.875 9)和G(0.787 9),Ci值排名后三名的为I(0.414 2)、W(0.413 7)和N(0.407 7)。在秩和比法评价中,RSR值排名前三名的为A(0.890 6)、G(0.765 6)和C(0.711 8),RSR值排名后三名的为V(0.381 9)、W(0.362 8)和K(0.357 6)。根据模糊集理论,将W1Ci+W2RSR值进行排序,依据"择多原则",排名前三名的分别为A、C和G,排名后三名的分别为I、K和W,这与TOPSIS法和秩和比法的评价结果基本一致。结论TOPSIS法和秩和比法模糊联合得到的评价结果及影响因素与其他研究结果相一致,并且两者联用能克服单一使用TOPSIS法或秩和比法的局限性,适宜在基本公共卫生服务质量评价中推广应用。 相似文献
8.
C. Vogrig J.-S. Louis F. Avila R. Gillet G. Hossu A. Blum-Moyse P.A. Gondim Teixeira 《Diagnostic and interventional imaging》2021,102(3):181-187
PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences. 相似文献
9.
《Diagnostic and interventional imaging》2021,102(10):629-639
PurposeTo investigate the reproducibility of diffusion-weighted (DW) MRI and 18F-Fluorodeoxyglucose (18F-FDG)-Positron emission tomography/CT (PET/CT) in monitoring response to neoadjuvant chemotherapy in epithelial ovarian cancer.Materials and methodsTen women (median age, 67 years; range: 41.8–77.3 years) with stage IIIC-IV epithelial ovarian cancers were included in this prospective trial (NCT02792959) between 2014 and 2016. All underwent initial laparoscopic staging, four cycles of carboplatine-paclitaxel-based chemotherapy and interval debulking surgery. PET/CT and DW-MRI were performed at baseline (C0), after one cycle (C1) and before surgery (C4). Two nuclear physicians and two radiologists assessed five anatomic sites for the presence of ≥ 1 lesion. Target lesions in each site were defined and their apparent diffusion coefficient (ADC), maximal standardized uptake value (SUV-max), SUV-mean, SUL-peak, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were monitored (i.e., 10 patients × 5 sites × 3 time-points). Their relative early and late changes were calculated. Intra/inter-observer reproducibilities of qualitative and quantitative analysis were estimated with Kappa and intra-class correlation coefficients (ICCs).ResultsFor both modalities, inter- and intra-observer agreement percentages were excellent for initial staging but declined later for DW-MRI, leading to lower Kappa values for inter- and intra-observer variability (0.949 and 1 at C0, vs. 0.633 and 0.643 at C4, respectively) while Kappa values remained > 0.8 for PET/CT. Inter- and intra-observer ICCs were > 0.75 for SUV-max, SUL-peak, SUV-mean and their change regardless the time-point. ADC showed lower ICCs (range: 0.013–0.811). ANOVA found significant influences of the evaluation time, the measurement used (ADC, SUV-max, SUV-mean, SUV-max, SUL-peak, MTV or TLG) and their interaction on ICC values (P = 0.0023, P< 0.0001 and P =0.0028, respectively).ConclusionWhile both modalities demonstrated high reproducibility at baseline, only SUV-max, SUL-peak, SUV-mean and their changes maintained high reproducibility during chemotherapy. 相似文献
10.
《Research in social & administrative pharmacy》2022,18(9):3699-3703
As one of the overreaching goals of Healthy People 2030, addressing the social determinants of health (SDOH) to reduce health disparities is a nationwide concern, with objectives informed by interdisciplinary teams of experts. However, there remains much discussion regarding the roles of healthcare providers in addressing SDOH. While current guidance suggests that all members of the healthcare team must be empowered to address SDOH, current guidance explicitly references physicians, nurses, social workers and staff, and do not specifically include pharmacists. While pharmacists are taught about the impact of SDOH in pharmacy curricula, actionable strategies for pharmacists to address SDOH in practice have not been clearly outlined. Pharmacists have multifaceted interactions with patients and may be influential in meeting individual patient needs, identifying social risk factors, and addressing upstream causes of health disparities. This paper proposes a framework for the role of pharmacists in addressing the SDOH through strategies at the patient, practice, and community levels. The concepts presented in this paper are meant to serve as a launch point for discussion and to promote the inclusion of pharmacists in the conversations around sustainable efforts to achieve health equity. This framework is not intended to limit the scope of pharmacists in addressing SDOH – on the contrary, it is our hope that this outline may be used to expand the education of future healthcare professionals regarding their role in addressing the social determinants of health. 相似文献