全文获取类型
收费全文 | 6478篇 |
免费 | 608篇 |
国内免费 | 19篇 |
专业分类
耳鼻咽喉 | 45篇 |
儿科学 | 219篇 |
妇产科学 | 130篇 |
基础医学 | 788篇 |
口腔科学 | 182篇 |
临床医学 | 811篇 |
内科学 | 1217篇 |
皮肤病学 | 57篇 |
神经病学 | 561篇 |
特种医学 | 216篇 |
外科学 | 943篇 |
综合类 | 169篇 |
一般理论 | 27篇 |
预防医学 | 741篇 |
眼科学 | 57篇 |
药学 | 513篇 |
1篇 | |
中国医学 | 9篇 |
肿瘤学 | 419篇 |
出版年
2023年 | 66篇 |
2022年 | 122篇 |
2021年 | 307篇 |
2020年 | 139篇 |
2019年 | 256篇 |
2018年 | 289篇 |
2017年 | 182篇 |
2016年 | 160篇 |
2015年 | 156篇 |
2014年 | 236篇 |
2013年 | 348篇 |
2012年 | 422篇 |
2011年 | 509篇 |
2010年 | 209篇 |
2009年 | 188篇 |
2008年 | 328篇 |
2007年 | 305篇 |
2006年 | 295篇 |
2005年 | 291篇 |
2004年 | 266篇 |
2003年 | 210篇 |
2002年 | 187篇 |
2001年 | 112篇 |
2000年 | 82篇 |
1999年 | 78篇 |
1998年 | 50篇 |
1997年 | 32篇 |
1996年 | 40篇 |
1995年 | 44篇 |
1994年 | 35篇 |
1993年 | 42篇 |
1992年 | 68篇 |
1991年 | 72篇 |
1990年 | 100篇 |
1989年 | 77篇 |
1988年 | 60篇 |
1987年 | 76篇 |
1986年 | 78篇 |
1985年 | 60篇 |
1984年 | 43篇 |
1983年 | 38篇 |
1982年 | 27篇 |
1981年 | 39篇 |
1980年 | 21篇 |
1979年 | 57篇 |
1978年 | 29篇 |
1977年 | 34篇 |
1976年 | 25篇 |
1975年 | 22篇 |
1971年 | 18篇 |
排序方式: 共有7105条查询结果,搜索用时 15 毫秒
1.
Improvement in Tricuspid Annular Plane Systolic Excursion with Pulmonary Hypertension Therapy in Pediatric Patients
下载免费PDF全文
![点击此处可从《Echocardiography (Mount Kisco, N.Y.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
2.
Nidogen 1 (NID1) is a glycoprotein found in basement membranes involved in cross-linking collagen IV and laminin. The role of NID in breast cancer has only been evaluated in a small number of studies and the findings of these studies have been inconsistent. Our previous work revealed that highly tumorigenic murine mammary tumor cells express high levels of Nid1 while weakly tumorigenic mammary tumor cells express low levels of Nid1. To investigate Nid1, two stable knockdown lines were created, and Nid1 knockdown was confirmed at both the mRNA and protein level. Nid1 knockdown significantly reduced cell proliferation and migration/invasion and these reductions in proliferation and migration/invasion could be rescued by conditioned media containing NID1 protein. The reduced migration/invasion observed in the Nid1 knockdown cells was not associated with significant alterations in the epithelial gene Cdh1 or the mesenchymal genes Snai1, Snai2, Twist1, Twist2, Zeb1 and Zeb2. Therefore, suppression of Nid1 expression reduces proliferation and migration/invasion in claudin-low murine mammary tumor cells. 相似文献
3.
4.
Hagop Kantarjian Tapan Kadia Courtney DiNardo Naval Daver Gautam Borthakur Elias Jabbour Guillermo Garcia-Manero Marina Konopleva Farhad Ravandi 《Blood cancer journal》2021,11(2)
Progress in the understanding of the biology and therapy of acute myeloid leukemia (AML) is occurring rapidly. Since 2017, nine agents have been approved for various indications in AML. These included several targeted therapies like venetoclax, FLT3 inhibitors, IDH inhibitors, and others. The management of AML is complicated, highlighting the need for expertise in order to deliver optimal therapy and achieve optimal outcomes. The multiple subentities in AML require very different therapies. In this review, we summarize the important pathophysiologies driving AML, review current therapies in standard practice, and address present and future research directions.Subject terms: Prognosis, Health services 相似文献
5.
Bimal Bhindi Christine M. Lohse Phillip J. Schulte Ross J. Mason John C. Cheville Stephen A. Boorjian Bradley C. Leibovich R. Houston Thompson 《European urology》2019,75(5):766-772
Background
Partial nephrectomy (PN) is generally favored for cT1 tumors over radical nephrectomy (RN) when technically feasible. However, it can be unclear whether the additional risks of PN are worth the magnitude of renal function benefit.Objective
To develop preoperative tools to predict long-term estimated glomerular filtration rate (eGFR) beyond 30 d following PN and RN, separately.Design, setting, and participants
In this retrospective cohort study, patients who underwent RN or PN for a single nonmetastatic renal tumor between 1997 and 2014 at our institution were identified. Exclusion criteria were venous tumor thrombus and preoperative eGFR <15 ml/min/1.73 m2.Intervention
RN and PN.Outcome measurements and statistical analysis
Hierarchical generalized linear mixed-effect models with backward selection of candidate preoperative features were used to predict long-term eGFR following RN and PN, separately. Predictive ability was summarized using marginal , which ranges from 0 to 1, with higher values indicating increased predictive ability.Results and limitations
The analysis included 1152 patients (13 206 eGFR observations) who underwent RN and 1920 patients (18 652 eGFR observations) who underwent PN, with mean preoperative eGFRs of 66 ml/min/1.73 m2 (standard deviation [SD] = 18) and 72 ml/min/1.73 m2 (SD = 20), respectively. The model to predict eGFR after RN included age, diabetes, preoperative eGFR, preoperative proteinuria, tumor size, time from surgery, and an interaction between time from surgery and age (marginal ). The model to predict eGFR after PN included age, presence of a solitary kidney, diabetes, hypertension, preoperative eGFR, preoperative proteinuria, surgical approach, time from surgery, and interaction terms between time from surgery and age, diabetes, preoperative eGFR, and preoperative proteinuria (marginal ). Limitations include the lack of data on renal tumor complexity and the single-center design; generalizability needs to be confirmed in external cohorts.Conclusions
We developed preoperative tools to predict renal function outcomes following RN and PN. Pending validation, these tools should be helpful for patient counseling and clinical decision-making.Patient summary
We developed models to predict kidney function outcomes after partial and radical nephrectomy based on preoperative features. This should help clinicians during patient counseling and decision-making in the management of kidney tumors. 相似文献6.
7.
Leonard A. Jason PhD Steven B. Pokorny PhD Monica Adams MPH Annie Topliff MA Courtney Harris BA Yvonne Hunt PhD 《The American journal on addictions / American Academy of Psychiatrists in Alcoholism and Addictions》2009,18(5):367-374
This study evaluated the effects of tobacco Purchase, Use and Possession (PUP) laws on student perceptions of adolescent tobacco use within towns and schools. Twenty‐four towns were randomly assigned into two conditions, the experimental condition (E PUP) involved efforts to increase both PUP law enforcement and reduce minors' access to commercial sources of tobacco, whereas the control condition (C) focused only on efforts to reduce minors' access to commercial sources of tobacco. A hierarchical linear modeling analytical approach was selected due to the multilevel data and nested design. The present study found that over time, youth in the experimental PUP condition observed less youth tobacco usage at school and in their town, and perceived lower rates of tobacco among their peers at school and among friends than youth in the control condition. The findings suggest that PUP law enforcement might be used to strengthen community norms against youth tobacco use. 相似文献
8.
The Executive Nurse Council was challenged to develop strategies designed to empower staff nurses and nurse managers and create opportunities for professional growth. Implementation of these strategies resulted in broad-sweeping changes in roles and functions of groups and individuals at all levels of the organization. The authors describe a support role, administrative nurse specialist, designed to support staff and managers striving to actualize changes in a shared governance framework. 相似文献
9.
10.
In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population. 相似文献