全文获取类型
收费全文 | 81470篇 |
免费 | 7857篇 |
国内免费 | 475篇 |
专业分类
耳鼻咽喉 | 290篇 |
儿科学 | 2749篇 |
妇产科学 | 2042篇 |
基础医学 | 3962篇 |
口腔科学 | 1782篇 |
临床医学 | 24729篇 |
内科学 | 9903篇 |
皮肤病学 | 717篇 |
神经病学 | 4139篇 |
特种医学 | 752篇 |
外科学 | 6237篇 |
综合类 | 5861篇 |
一般理论 | 66篇 |
预防医学 | 16930篇 |
眼科学 | 340篇 |
药学 | 5497篇 |
126篇 | |
中国医学 | 919篇 |
肿瘤学 | 2761篇 |
出版年
2024年 | 251篇 |
2023年 | 2737篇 |
2022年 | 3295篇 |
2021年 | 4593篇 |
2020年 | 4822篇 |
2019年 | 4813篇 |
2018年 | 4473篇 |
2017年 | 3941篇 |
2016年 | 3536篇 |
2015年 | 3379篇 |
2014年 | 6132篇 |
2013年 | 6923篇 |
2012年 | 4592篇 |
2011年 | 4710篇 |
2010年 | 3504篇 |
2009年 | 3601篇 |
2008年 | 3330篇 |
2007年 | 3439篇 |
2006年 | 2909篇 |
2005年 | 2414篇 |
2004年 | 2016篇 |
2003年 | 1568篇 |
2002年 | 1195篇 |
2001年 | 1074篇 |
2000年 | 960篇 |
1999年 | 810篇 |
1998年 | 688篇 |
1997年 | 556篇 |
1996年 | 483篇 |
1995年 | 371篇 |
1994年 | 354篇 |
1993年 | 316篇 |
1992年 | 232篇 |
1991年 | 229篇 |
1990年 | 199篇 |
1989年 | 151篇 |
1988年 | 118篇 |
1987年 | 121篇 |
1986年 | 105篇 |
1985年 | 162篇 |
1984年 | 126篇 |
1983年 | 124篇 |
1982年 | 113篇 |
1981年 | 79篇 |
1980年 | 71篇 |
1979年 | 52篇 |
1978年 | 24篇 |
1977年 | 30篇 |
1976年 | 33篇 |
1975年 | 13篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Anela Stanic Denis Rybin Francis Cannata Carole Hohl Jennifer Brody Jessie Gaeta 《AIDS care》2021,33(1):1-9
ABSTRACT The lack of stable housing can impair access and continuity of care for patients living with human immunodeficiency virus (HIV). This study investigated the relationship between housing status assessed at multiple time points and several core HIV-related outcomes within the same group of HIV patients experiencing homelessness. Patients with consistently stable housing (CSH) during the year were compared to patients who lacked CSH (non-CSH group). The study outcomes included HIV viral load (VL), CD4 counts, and health care utilization. Multivariable and propensity weighted analyses were used to assess outcomes adjusting for potential group differences. Of 208 patients, 88 (42%) had CSH and 120 (58%) were non-CSH. Patients with CSH had significantly higher proportion of VL suppression and higher mean CD4 counts. The frequency of nurse visits in the CSH group was less than a half of that in the non-CSH group. Patients with CSH were less likely to be admitted to the medical respite facility, and if admitted, their length of stay was about a half of that for the non-CSH group. Our study findings show that patients with CSH had significantly better HIV virologic control and immune status as well as improved health care utilization. 相似文献
2.
Hideyuki Masuda Makoto Kimura Akiko Nishioka Hiroshi Kato Akimichi Morita 《Journal of dermatological science》2019,93(2):109-115
Background
Photosensitizers used for photodynamic therapy (PDT) to treat dermatologic disease are metabolized into mainly protoporphyrin IX (PpIX), which has five absorption wavelength peaks: 410?nm, 510?nm, 545?nm, 580?nm, and 630?nm. Although only red light around 635?nm and blue light around 400?nm are used as light sources for PDT, the efficiency of PDT might be improved by using multiple wavelengths, including those that correspond to the other absorption peaks of PpIX. Furthermore, because the target disease often occurs on the face, a flexible-type light-source unit that can be fitted to the lesion without unnecessarily exposing the mucous membranes, e.g., the eyes, nostrils, and mouth, is preferred.Objective
We investigated the efficacy of a flexible light-emitting diode (LED) unit that emits multiple wavelengths to improve PDT effects.Methods
HaCaT cells were incubated with 5-ALA and subsequently irradiated with either a single wavelength or sequentially with two wavelengths. Cell viability and reactive oxygen species were analyzed. Nude mice were implanted with COLO679 cells by subcutaneous injection into the flank. 5-ALA was subcutaneously injected into the tumor. The tumor was irradiated with 50?J/cm2 (day 0) and assessed daily until day 21.Results
The synergistic PDT effects of dual-wavelength irradiation and reactive oxygen species production were highest with the 405-nm and 505-nm wavelength combination. This dual wavelength combination was also the most effective in vivo.Conclusion
We could therefore conclude that dual-wavelength PDT is an efficient strategy for improving the therapeutic effects of PDT. Using a flexible LED unit is expected to achieve more uniform irradiation of uneven areas. 相似文献3.
Ehsan Zarei Elmira Madarshahian Adeleh Nikkhah Soheila Khodakarim 《Journal of tissue viability》2019,28(2):70-74
Background and objective
Pressure ulcer (PU) is one of the important and frequent complications of hospitalization, associated with high treatment costs. The present study was conducted to determine the incidence of PU and its direct treatment costs for patients in intensive care unit (ICU) in Iran.Material and methods
In this retrospective study, medical records of 643 discharged patients from ICU of two selected hospitals were examined. The demographic and clinical data of all patients and data of resources and services usage for patients with PU were extracted through their records. Data analysis was done using logistic regression tests in SPSS 22 software. The cost of PU treatment was calculated for each grade of ulcer.Results
The findings showed that 8.9% of patients developed PU during their stay in ICU. Muscular paralysis (OR?=?5.1), length of stay in ICU (OR?=?4.0), diabetes (OR?=?3.5) age (OR?=?2.9), smoking (OR?=?2.1) and trauma (OR?=?1.4) were the most important risk factors of PU. The average cost of PU treatment varied from USD 12 for grade I PU to USD 66?834 for grade IV PUs. The total treatment costs for all studied patients with PU was estimated at USD 519?991.Conclusion
The cost of PU treatment is significant. Since the preventive measures are more cost-effective than therapeutic measures, therefore, effective preventive interventions are recommended. 相似文献4.
5.
6.
Eric S. Zhou Larissa Nekhlyudov Sharon L. Bober 《Translational andrology and urology》2015,4(2):218-231
There is a large and growing population of long-term cancer survivors. Primary care physicians (PCPs) are playing an increasingly greater role in the care of these patients across the continuum of cancer survivorship. In this role, PCPs are faced with the responsibility of managing a range of medical and psychosocial late effects of cancer treatment. In particular, the sexual side effects of treatment which are common and have significant impact on quality of life for the cancer survivor, often go unaddressed. This is an area of clinical care and research that has received increasing attention, highlighted by the presentation of this special issue on Cancer and Sexual Health. The aims of this review are 3-fold. First, we seek to overview common presentations of sexual dysfunction related to major cancer diagnoses in order to give the PCP a sense of the medical issues that the survivor may present with. Barriers to communication about sexual health issues between patient/PCPs in order are also described in order to emphasize the importance of PCPs initiating this important conversation. Next, we provide strategies and resources to help guide the PCP in the management of sexual dysfunction in cancer survivors. Finally, we discuss case examples of survivorship sexual health issues and highlight the role that a PCP can play in each of these case examples. 相似文献
7.
ObjectivesTo fill an empirical gap in the literature by examining changes in quality of care measures occurring when multispecialty clinic systems were acquired by hospital-owned, vertically integrated health care delivery systems in the Twin Cities area.ConclusionsMoving a clinic system into a vertically integrated delivery system resulted in limited increases in quality of care indicators. Caution is warranted when the acquisition causes disruption in referral patterns. 相似文献
8.
9.
Stephan Koter Tina U. Cohnert Korbinian B. Hindermayr Jörg Lindenmann Maximilian Brückner Wolfgang K. Oswald Georg Werkgartner Doris Wagner 《Journal of vascular surgery》2019,69(4):1227-1232
Objective
Low psoas muscle area is shown to be an indicator for worse postoperative outcome in patients undergoing vascular surgical. Additionally, it has been associated with longer durations of hospital stay in patients with cancer who undergo surgery and subsequently greater health care costs in Europe and the United States. We sought to evaluate this effect on hospital expenditure for patients undergoing vascular repair in a health care system with universal access.Methods
Skeletal muscle mass was assessed on preoperative abdominal computed tomography scans of patients undergoing open aortic aneurysm repair in a retrospective fashion. The skeletal muscle index (SMI) was used to define low muscle mass. Health care costs were obtained for all patients and the relationship between a low SMI and higher costs was explored using linear regression and cross-sectional analysis.Results
We included 156 patients (81.5% male) with a median age of 72 years undergoing elective surgery for infrarenal abdominal aortic aneurysm in this analysis. The median SMI for patients with low skeletal muscle mass was 53.21 cm2/kg and for patients without, 70.07 cm2/kg. Hospital duration of stay was 2 days longer in patients with low skeletal muscle mass as compared with patients with normal (14 days vs 11 days; P = .001), as was duration of intensive care stay (3 days vs 1 day; P = .01). The median overall hospital costs were €10,460 higher for patients with a low SMI as compared with patients with a normal physical constitution (€53,739 [interquartile range, €45,007-€62,471] vs €43,279 [interquartile range, €39,509-€47,049]; P = .001). After confounder adjustment, a low SMI was associated with a 14.68% cost increase in overall hospital costs, for a cost increase of €6521.Conclusions
Low skeletal muscle mass is independently associated with higher hospital as well as intensive care costs in patients undergoing elective aortic aneurysm repair. Strategies to reduce this risk factor are warranted for these patients. 相似文献10.
Tian-Yuan Xiong Fang-Yang Huang Qi Liu Yong Peng Yuan-Ning Xu Jia-Fu Wei 《Annals of medicine》2020,52(7):361-366
Abstract