全文获取类型
收费全文 | 1485952篇 |
免费 | 104775篇 |
国内免费 | 1995篇 |
专业分类
耳鼻咽喉 | 19288篇 |
儿科学 | 47766篇 |
妇产科学 | 39715篇 |
基础医学 | 220780篇 |
口腔科学 | 40267篇 |
临床医学 | 135678篇 |
内科学 | 295560篇 |
皮肤病学 | 32742篇 |
神经病学 | 121889篇 |
特种医学 | 53632篇 |
外国民族医学 | 363篇 |
外科学 | 206563篇 |
综合类 | 26658篇 |
现状与发展 | 3篇 |
一般理论 | 631篇 |
预防医学 | 124989篇 |
眼科学 | 32411篇 |
药学 | 108186篇 |
6篇 | |
中国医学 | 2708篇 |
肿瘤学 | 82887篇 |
出版年
2021年 | 12880篇 |
2019年 | 13772篇 |
2018年 | 20534篇 |
2017年 | 15090篇 |
2016年 | 16082篇 |
2015年 | 18396篇 |
2014年 | 23571篇 |
2013年 | 36295篇 |
2012年 | 52846篇 |
2011年 | 55449篇 |
2010年 | 30714篇 |
2009年 | 28056篇 |
2008年 | 50857篇 |
2007年 | 54508篇 |
2006年 | 52916篇 |
2005年 | 51901篇 |
2004年 | 49610篇 |
2003年 | 47052篇 |
2002年 | 45229篇 |
2001年 | 60988篇 |
2000年 | 62117篇 |
1999年 | 52608篇 |
1998年 | 14265篇 |
1997年 | 12967篇 |
1996年 | 13328篇 |
1995年 | 12539篇 |
1994年 | 11639篇 |
1992年 | 40919篇 |
1991年 | 40132篇 |
1990年 | 38842篇 |
1989年 | 37451篇 |
1988年 | 34797篇 |
1987年 | 33981篇 |
1986年 | 32409篇 |
1985年 | 30498篇 |
1984年 | 23258篇 |
1983年 | 20291篇 |
1982年 | 12022篇 |
1979年 | 22096篇 |
1978年 | 16213篇 |
1977年 | 13572篇 |
1976年 | 12479篇 |
1975年 | 13576篇 |
1974年 | 16517篇 |
1973年 | 16312篇 |
1972年 | 15439篇 |
1971年 | 14440篇 |
1970年 | 13586篇 |
1969年 | 12938篇 |
1968年 | 11995篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Susan E. Hickman Alexia M. Torke Greg A. Sachs Rebecca L. Sudore Anne L. Myers Qing Tang Giorgos Bakoyannis Bernard J. Hammes 《Journal of pain and symptom management》2019,57(6):1143-1150.e5
ContextIt is especially important that patients are well informed when making high-stakes, preference-sensitive decisions like those on the Physician Orders for Life-Sustaining Treatment (POLST) form. However, there is currently no way to easily evaluate whether patients understand key concepts when making these important decisions.ObjectivesTo develop a POLST knowledge survey.MethodsExpert (n = 62) ratings of key POLST facts were used to select items for a POLST knowledge survey. The survey was administered to nursing facility residents (n = 97) and surrogate decision-makers (n = 112). A subset (n = 135) were re-administered the survey after a standardized advance care planning discussion to assess the scale's responsiveness to change.ResultsThe 19-item survey demonstrated adequate reliability (α = 0.72.). Residents' scores (x = 11.4, standard deviation 3.3) were significantly lower than surrogate scores (x = 14.7, standard deviation 2.5) (P < 0.001). Scores for both groups increased significantly after administration of a standardized advance care planning discussion (P < 0.001). Although being a surrogate, age, race, education, cognitive functioning, and health literacy were significantly associated with higher POLST Knowledge Survey scores in univariate analyses, only being a surrogate (P < 0.001) and being white (P = 0.028) remained significantly associated with higher scores in multivariate analyses.ConclusionThe 19-item POLST Knowledge Survey demonstrated adequate reliability and responsiveness to change. Findings suggest the survey could be used to identify knowledge deficits and provide targeted education to ensure adequate understanding of key clinical decisions when completing POLST. 相似文献
22.
Amosova E. N. Shilova I. V. Zueva E. P. Rybalkina O. Yu. 《Pharmaceutical Chemistry Journal》2020,54(7):721-724
Pharmaceutical Chemistry Journal - Three extracts were produced from the above-ground part of the meadowsweet Filipendula ulmaria (L.) Maxim. using water, 40% ethanol, and 70% ethanol. Comparative... 相似文献
23.
Caroline E. Sloan Judy Zhong Dinushika Mohottige Rasheeda Hall Clarissa J. Diamantidis Leight E. Boulware Virginia Wang 《Seminars in dialysis》2020,33(6):440-448
Caring for patients with end-stage kidney disease (ESKD) in the United States is challenging, due in part to the complex epidemiology of the disease's progression as well as the ways in which care is delivered. As CKD progresses toward ESKD, the number of comorbidities increases and care involves multiple healthcare providers from multiple subspecialties. This occurs in the context of a fragmented US healthcare delivery system that is traditionally siloed by provider specialty, organization, as well as systems of payment and administration. This article describes the role of care fragmentation in the delivery of optimal ESKD care and identifies research gaps in the evidence across the continuum of care. We then consider the impact of care fragmentation on ESKD care from the patient and health system perspectives and explore opportunities for system-level interventions aimed at improving care for patients with ESKD. 相似文献
24.
As millions of people turn to social media for health information, better understanding the factors that guide health-related judgments and perceptions in this context is imperative. We report on two Web experiments (n > 400 total) examining the power of society’s widespread weight bias and related stereotypes to influence nutrition judgments in social media spaces. In Experiment 1, meals were judged as lower in nutritional quality when the person who recommended them (the source) was depicted as obese rather than of normal weight, an effect mediated by stereotypic beliefs about the source as a generally unhealthy person. Experiment 2 replicated this effect, which—notably—remained significant when controlling for objective nutritional information (calories and fat content). Results highlight spillover effects of weight bias that extend beyond person perception to color impressions of objects (here, food) that are associated with stigmatized attributes. Implications for everyday nutrition judgments and public health are considered. 相似文献
25.
26.
27.
28.
Zaida Araujo Sietze Brandes Elena Pinelli María A. Bochichio Andrea Palacios Albina Wide Bruno Rivas-Santiago Juan Carlos Jiménez 《Revista do Instituto de Medicina Tropical de S?o Paulo》2015,57(1):47-55
The present study aimed at measuring seropositivities for infection by
Ascaris suum and Toxocara canis using the
excretory/secretory (E/S) antigens from Ascaris suum (AES) and
Toxocara canis (TES) within an indigenous population. In
addition, quantification of cytokine expressions in peripheral blood cells was
determined. A total of 50 Warao indigenous were included; of which 43 were adults and
seven children. In adults, 44.1% were seropositive for both parasites; whereas
children had only seropositivity to one or the other helminth. For ascariosis, the
percentage of AES seropositivity in adults and children was high; 23.3% and 57.1%,
respectively. While that for toxocariosis, the percentage of TES seropositivity in
adults and children was low; 9.3% and 14.3%, respectively. The percentage of
seronegativity was comparable for AES and TES antigens in adults (27.9%) and children
(28.6%). When positive sera were analyzed by Western blotting technique using AES
antigens; three bands of 97.2, 193.6 and 200.2 kDas were mostly recognized. When the
TES antigens were used, nine major bands were mostly identified; 47.4, 52.2, 84.9,
98.2, 119.1, 131.3, 175.6, 184.4 and 193.6 kDas. Stool examinations showed that
Blastocystis hominis, Hymenolepis nana and
Entamoeba coli were the most commonly observed intestinal
parasites. Quantification of cytokines IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 and
IL-4 expressions showed that there was only a significant increased expression of
IL-4 in indigenous with TES seropositivity (p < 0.002).
Ascaris and Toxocara seropositivity was
prevalent among Warao indigenous. 相似文献
29.
30.
E. Niclas Jonsson Rujia Xie Scott F. Marshall Rosalin H. Arends 《British journal of clinical pharmacology》2016,81(4):688-699
AimsThe aims were to 1) develop the pharmacokinetics model to describe and predict observed tanezumab concentrations over time, 2) test possible covariate parameter relationships that could influence clearance and distribution and 3) assess the impact of fixed dosing vs. a dosing regimen adjusted by body weight.MethodsIndividual concentration–time data were determined from 1608 patients in four phase 3 studies conducted to assess efficacy and safety of intravenous tanezumab. Patients received two or three intravenous doses (2.5, 5 or 10 mg) every 8 weeks. Blood samples for assessment of tanezumab PK were collected at baseline, 1 h post‐dose and at weeks 4, 8, 16 and 24 (or early termination) in all studies. Blood samples were collected at week 32 in two studies. Plasma samples were analyzed using a sensitive, specific, validated enzyme‐linked immunosorbent assay.ResultsA two compartment model with parallel linear and non‐linear elimination processes adequately described the data. Population estimates for clearance (CL), central volume (V
1), peripheral volume (V
2), inter‐compartmental clearance, maximum elimination capacity (VM) and concentration at half‐maximum elimination capacity were 0.135 l day–1, 2.71 l, 1.98 l, 0.371 l day–1, 8.03 μg day–1 and 27.7 ng ml–1, respectively. Inter‐individual variability (IIV) was included on CL, V
1, V
2 and VM. A mixture model accounted for the distribution of residual error. While gender, dose and creatinine clearance were significant covariates, only body weight as a covariate of CL, V
1 and V
2 significantly reduced IIV.ConclusionsThe small increase in variability associated with fixed dosing is consistent with other monoclonal antibodies and does not change risk : benefit. 相似文献