全文获取类型
收费全文 | 1210224篇 |
免费 | 96673篇 |
国内免费 | 19140篇 |
专业分类
耳鼻咽喉 | 15362篇 |
儿科学 | 30093篇 |
妇产科学 | 33380篇 |
基础医学 | 161658篇 |
口腔科学 | 32892篇 |
临床医学 | 112413篇 |
内科学 | 227299篇 |
皮肤病学 | 26866篇 |
神经病学 | 92758篇 |
特种医学 | 48853篇 |
外国民族医学 | 283篇 |
外科学 | 180251篇 |
综合类 | 65138篇 |
现状与发展 | 51篇 |
一般理论 | 330篇 |
预防医学 | 92256篇 |
眼科学 | 27307篇 |
药学 | 95828篇 |
233篇 | |
中国医学 | 15987篇 |
肿瘤学 | 66799篇 |
出版年
2022年 | 15442篇 |
2021年 | 20425篇 |
2020年 | 15098篇 |
2019年 | 15934篇 |
2018年 | 16455篇 |
2017年 | 15077篇 |
2016年 | 15754篇 |
2015年 | 20660篇 |
2014年 | 26769篇 |
2013年 | 33231篇 |
2012年 | 41403篇 |
2011年 | 44430篇 |
2010年 | 29382篇 |
2009年 | 26936篇 |
2008年 | 36850篇 |
2007年 | 38085篇 |
2006年 | 38323篇 |
2005年 | 37057篇 |
2004年 | 33147篇 |
2003年 | 32224篇 |
2002年 | 29983篇 |
2001年 | 43087篇 |
2000年 | 43037篇 |
1999年 | 37674篇 |
1998年 | 14652篇 |
1997年 | 13821篇 |
1996年 | 13256篇 |
1995年 | 13213篇 |
1994年 | 12503篇 |
1993年 | 11019篇 |
1992年 | 30961篇 |
1991年 | 30170篇 |
1990年 | 29053篇 |
1989年 | 28254篇 |
1988年 | 26314篇 |
1987年 | 25926篇 |
1986年 | 24594篇 |
1985年 | 24012篇 |
1984年 | 18943篇 |
1983年 | 16341篇 |
1982年 | 10920篇 |
1979年 | 18461篇 |
1978年 | 13790篇 |
1977年 | 11881篇 |
1975年 | 11484篇 |
1974年 | 13680篇 |
1973年 | 13078篇 |
1972年 | 12336篇 |
1971年 | 11387篇 |
1970年 | 10864篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
目的分析脑出血围手术期护理安全中细节管理的重要性。方法将于2018年6-10月在该院接受治疗的60例脑出血围术期患者作为该研究的常规组。将于2018年11月-2019年3月在该院接受治疗的60例脑出血围术期患者作为该研究的细节组。该院于2018年11月开始实施细节管理,以加强保障脑出血围术期患者的安全。对比两组患者的护理满意度、手术失败率、死亡率、住院时间及日常生活能力。结果细节组护理满意度明显高于常规组(P<0.05)。常规组的手术失败率、死亡率为均高于细节组,差异无统计学意义(P>0.05);细节组的住院时间明显短于常规组(P<0.05),ADL评分明显大于常规组(P<0.05)。结论细节管理在脑出血围手术期护理安全中具有相当重要性,可提升护理满意度,加快恢复速度,提升恢复效果。 相似文献
2.
3.
4.
Stelter K. Theodoraki M. N. Becker S. Tsekmistrenko V. Olzowy B. Ledderose G. 《European archives of oto-rhino-laryngology》2015,272(3):639-639
European Archives of Oto-Rhino-Laryngology - 相似文献
5.
Katherine M. Duszynski Nicole L. Pratt John W. Lynch Jesia G. Berry Michael S. Gold 《Vaccine》2019,37(2):280-288
Objective
To determine whether differences in combination DTaP vaccine types at 2, 4 and 6?months of age were associated with mortality (all-cause or non-specific), within 30?days of vaccination.Design
Observational nationwide cohort study.Setting
Linked population data from the Australian Childhood Immunisation Register and National Death Index.Participants
Australian infants administered a combination trivalent, quadrivalent or hexavalent DTaP vaccine (DTaP types) between January 1999 and December 2010 at 2, 4 and 6?months as part of the primary vaccination series. The study population included 2.9, 2.6, & 2.3?million children in the 2, 4 and 6?month vaccine cohorts, respectively.Main outcome measures
Infants were evaluated for the primary outcome of all-cause mortality within 30?days. A secondary outcome was non-specific mortality (unknown cause of death) within 30?days of vaccination. Non-specific mortality was defined as underlying or other cause of death codes, R95 ‘Sudden infant death syndrome’, R96 ‘Other sudden death, cause unknown’, R98 ‘Unattended death’, R99 ‘Other ill-defined and unspecified cause of mortality’ or where no cause of death was recorded.Results
The rate of 30?day all-cause mortality was low and declined from 127.4 to 59.3 deaths per 100,000 person-years between 2 and 6?month cohorts. When compared with trivalent DTaP vaccines, no elevated risk in all-cause or non-specific mortality was seen with any quadrivalent or hexavalent DTaP vaccines, for any cohort.Conclusion
Use of routine DTaP combination vaccines with differing disease antigens administered during the first six months of life is not associated with infant mortality. 相似文献6.
A.W. van der Eerden T.L. van den Heuvel V. Perlbarg P. Vart P.E. Vos L. Puybasset D. Galanaud B. Platel R. Manniesing B.M. Goraj 《AJNR. American journal of neuroradiology》2021,42(5):861
BACKGROUND AND PURPOSE:In the chronic phase after traumatic brain injury, DTI findings reflect WM integrity. DTI interpretation in the subacute phase is less straightforward. Microbleed evaluation with SWI is straightforward in both phases. We evaluated whether the microbleed concentration in the subacute phase is associated with the integrity of normal-appearing WM in the chronic phase.MATERIALS AND METHODS:Sixty of 211 consecutive patients 18 years of age or older admitted to our emergency department ≤24 hours after moderate to severe traumatic brain injury matched the selection criteria. Standardized 3T SWI, DTI, and T1WI were obtained 3 and 26 weeks after traumatic brain injury in 31 patients and 24 healthy volunteers. At baseline, microbleed concentrations were calculated. At follow-up, mean diffusivity (MD) was calculated in the normal-appearing WM in reference to the healthy volunteers (MDz). Through linear regression, we evaluated the relation between microbleed concentration and MDz in predefined structures.RESULTS:In the cerebral hemispheres, MDz at follow-up was independently associated with the microbleed concentration at baseline (left: B = 38.4 [95% CI 7.5–69.3], P = .017; right: B = 26.3 [95% CI 5.7–47.0], P = .014). No such relation was demonstrated in the central brain. MDz in the corpus callosum was independently associated with the microbleed concentration in the structures connected by WM tracts running through the corpus callosum (B = 20.0 [95% CI 24.8–75.2], P < .000). MDz in the central brain was independently associated with the microbleed concentration in the cerebral hemispheres (B = 25.7 [95% CI 3.9–47.5], P = .023).CONCLUSIONS:SWI-assessed microbleeds in the subacute phase are associated with DTI-based WM integrity in the chronic phase. These associations are found both within regions and between functionally connected regions.The yearly incidence of traumatic brain injury (TBI) is around 300 per 100,000 persons.1,2 Almost three-quarters of patients with moderate to severe TBI have traumatic axonal injury (TAI).3 TAI is a major predictor of functional outcome,4,5 but it is mostly invisible on CT and conventional MR imaging.6,7DTI provides direct information on WM integrity and axonal injury.5,8 However, DTI abnormalities are neither specific for TAI nor stable over time. Possibly because of the release of mass effect and edema and resorption of blood products, the effects of concomitant (non-TAI) injury on DTI are larger in the subacute than in the chronic phase (>3 months).4,9,10 Therefore, DTI findings are expected to reflect TAI more specifically in the chronic than in the subacute phase (1 week–3 months).4 Even in regions without concomitant injury, the effects of TAI on DTI are dynamic, possibly caused by degeneration and neuroplastic changes.6,11,12 These ongoing pathophysiological processes possibly contribute to the emerging evidence that DTI findings in the chronic phase are most closely associated with the eventual functional outcome.12,13Although DTI provides valuable information, its acquisition, postprocessing, and interpretation in individual patients are demanding. SWI, with which microbleeds can be assessed with high sensitivity, is easier to interpret and implement in clinical practice. In contrast to DTI, SWI-detected traumatic microbleeds are more stable1 except in the hyperacute14,15 and the late chronic phases.16 Traumatic cerebral microbleeds are commonly interpreted as signs of TAI. However, the relation is not straightforward. On the one hand, nontraumatic microbleeds may be pre-existing. On the other hand, even if traumatic in origin, microbleeds represent traumatic vascular rather than axonal injury.17 Indeed, TAI is not invariably hemorrhagic.18 Additionally, microbleeds may secondarily develop after trauma through mechanisms unrelated to axonal injury, such as secondary ischemia.18DTI is not only affected by pathophysiological changes but also by susceptibility.19 The important susceptibility-effect generated by microbleeds renders the interpretation of DTI findings at the location of microbleeds complex. In the chronic phase, mean diffusivity (MD) is the most robust marker of WM integrity.4,6 For these reasons, we evaluated MD in the normal-appearing WM.Much TAI research focuses on the corpus callosum because it is commonly involved in TAI5,18,20 and it can reliably be evaluated with DTI,5,21 and TAI in the corpus callosum is related to clinical prognosis.6,20 The corpus callosum consists of densely packed WM tracts that structurally and functionally connect left- and right-sided brain structures.22 The integrity of the corpus callosum is associated with the integrity of the brain structures it connects.23 Therefore, microbleeds in brain structures that are connected through the corpus callosum may affect callosal DTI findings. Analogous to this, microbleeds in the cerebral hemispheres, which exert their function through WM tracts traveling through the deep brain structures and brain stem,24,25 may affect DTI findings in the WM of the latter.Our purpose was to evaluate whether the microbleed concentration in the subacute phase is associated with the integrity of normal-appearing WM in the chronic phase. We investigated this relation within the cerebral hemispheres and the central brain and between regions that are functionally connected by WM tracts. 相似文献
7.
目的 分析重庆市肺癌发病死亡和疾病负担归因于被动吸烟的情况,为开展肺癌防治提供建议。 方法 肺癌死亡个案数据来源于2019年重庆市肿瘤登记报告系统,被动吸烟率来自2013年重庆市慢性病及危险因素监测。计算人群归因危险度百分比(population attributable risk percent, PAR%)、被动吸烟导致的肺癌发病、死亡和疾病负担。采用Excel 2010与SPSS 25.0进行统计分析,率的比较采用χ2检验。 结果 2013年30岁及以上成年人被动吸烟率为52.37%。2019年重庆市30岁及以上人群肺癌发病率与标化发病率分别为118.44/10万与80.83/10万,死亡率与标化死亡率分别为96.51/10万、63.58/10万。肺癌发病率和死亡率归因于被动吸烟的PAR%分别为19.76和19.04,归因发病率与归因标化发病率分别为23.41/10万和16.34/10万,归因死亡率与归因标化死亡率分别为18.38/10万和12.40/10万。2019年重庆市30岁及以上肺癌早死所致寿命损失年率(years of life lost,YLL)、残疾所致寿命损失年率(years lived with disability,YLD)、调整伤残寿命损失年率(disability adjusted life year,DALY)分别为21.16‰、0.31‰、21.47‰,YLL率、YLD率、DALY率归因于被动吸烟的PAR%分别为21.16、19.76和20.49,归因YLL率为4.34‰,归因YLD率为0.06‰,归因DALY率为4.40‰。 结论 2019年重庆市30岁及以上人群肺癌发病率、死亡率、YLL率、DALY率高,被动吸烟率高,肺癌归因于被动吸烟的疾病负担重,应加强落实控烟工作。 相似文献
8.
目的:分析鼻塞式同步间歇正压通气(NIPPV)联合布地奈德雾化治疗ARDS(新生儿急性呼吸窘迫综合征)疾病的临床应用效果。方法:纳入病例是2017年5月—2019年11月收治的104例ARDS新生儿,随机平均分为两组。参照组52例采纳CPAP(持续气道正压通气通气)治疗,实验组52例采纳NIPPV+布地奈德雾化治疗,对比两组呼吸机通气时间、用氧时间、住院时间、血气指标以及并发症发生情况。结果:实验组呼吸机通气时间、用氧时间、住院时间均明显短于参照组,差异有统计学意义P<0.05;实验组治疗3 d后PaCO2明显低于参照组,实验组治疗3 d后PH以及PaO2明显高于参照组,差异有统计学意义P<0.05;实验组并发症发生率(3.85%,2/52)明显低于参照组(21.15%,11/52),差异有统计学意义P<0.05。结论:NIPPV+布地奈德雾化可有效缩短ARDS患者机械通气时间,改善血气指标,降低并发症发生率,值得借鉴。 相似文献
9.
10.