全文获取类型
收费全文 | 13608篇 |
免费 | 950篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 96篇 |
儿科学 | 465篇 |
妇产科学 | 399篇 |
基础医学 | 1721篇 |
口腔科学 | 148篇 |
临床医学 | 2331篇 |
内科学 | 2123篇 |
皮肤病学 | 173篇 |
神经病学 | 1314篇 |
特种医学 | 348篇 |
外科学 | 1351篇 |
综合类 | 254篇 |
一般理论 | 25篇 |
预防医学 | 1623篇 |
眼科学 | 284篇 |
药学 | 880篇 |
2篇 | |
中国医学 | 7篇 |
肿瘤学 | 1036篇 |
出版年
2023年 | 61篇 |
2022年 | 138篇 |
2021年 | 232篇 |
2020年 | 147篇 |
2019年 | 238篇 |
2018年 | 282篇 |
2017年 | 224篇 |
2016年 | 215篇 |
2015年 | 248篇 |
2014年 | 343篇 |
2013年 | 623篇 |
2012年 | 823篇 |
2011年 | 950篇 |
2010年 | 499篇 |
2009年 | 495篇 |
2008年 | 856篇 |
2007年 | 856篇 |
2006年 | 931篇 |
2005年 | 895篇 |
2004年 | 958篇 |
2003年 | 890篇 |
2002年 | 793篇 |
2001年 | 210篇 |
2000年 | 149篇 |
1999年 | 173篇 |
1998年 | 174篇 |
1997年 | 139篇 |
1996年 | 98篇 |
1995年 | 114篇 |
1994年 | 79篇 |
1993年 | 86篇 |
1992年 | 131篇 |
1991年 | 91篇 |
1990年 | 113篇 |
1989年 | 84篇 |
1988年 | 80篇 |
1987年 | 80篇 |
1986年 | 100篇 |
1985年 | 78篇 |
1984年 | 72篇 |
1983年 | 79篇 |
1982年 | 61篇 |
1981年 | 68篇 |
1980年 | 74篇 |
1979年 | 54篇 |
1978年 | 49篇 |
1977年 | 41篇 |
1976年 | 38篇 |
1975年 | 41篇 |
1973年 | 42篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
M. Alexandra Friedman Charlotte M. Niznik Janelle R. Bolden Lynn M. Yee 《Journal of community health》2016,41(2):354-358
While peer support has been investigated in multiple clinical contexts, its application to the postpartum setting is unknown. The aim was to assess acceptability of a postpartum peer support program for women with diabetes. Observational survey-based needs assessment of forty low-income women with diabetes, receiving care at a major medical institution. Mean age and gravidity were 30.7 years and 3.15 ± 1.67 respectively. 45 % expressed interest in a “buddy.” There was no significant difference between groups desiring and not desiring this program. A majority of respondents desired telephone, text messaging, and in-person contacts (79.2, 72.1, 83.8 %), with 72.5 % of patients desiring diabetes-related activities during clinic waiting time. Many women desire a postpartum diabetes reciprocal peer program for support outside of clinician visits. Patients are receptive to educational services during their wait and outside of clinic time, a potentially valuable opportunity to share important health information. 相似文献
3.
Peffault de Latour Rgis Huynh Lynn Ivanova Jasmina I. Totev Todor Bilginsoy Mehmet Antin Joseph Roy Anuja Duh Mei Sheng 《Annals of hematology》2020,99(4):743-752
Annals of Hematology - This study assessed treatment patterns and healthcare resource utilization (HRU) of patients with severe aplastic anemia (SAA) with insufficient response to immunosuppressive... 相似文献
4.
Purpose: To test the effectiveness of a school-based, nurse-facilitated support group in increasing perceptions of scholastic competence, social acceptance, behavioral conduct, perceived athletic competence, perceived physical appearance, and perceived global self-worth in preadolescents diagnosed with attention deficit disorder (ADD) or attention deficit hyperactivity disorder (ADHD).
Design: A quasi-experimental design with 65 preadolescents diagnosed with ADD or ADHD in an upper-middle class community in the United States.
Methods: Participants randomly assigned to either the control or experimental group completed Harter's Self-Perception Profile for Children instrument at the beginning of the study and 4 weeks later. Students in the experimental condition participated in a school-nurse facilitated support group which met twice weekly for 4 weeks.
Findings: Participants in the support group had increased scores on each of the six subscales, with significant increases on four of the subscales, including perceived social acceptance, perceived athletic competence, perceived physical appearance, and perceived global self-worth.
Conclusion: Participation in a school-based, nurse-led support group was positively associated with perception of self-worth in preadolescents diagnosed with ADD or ADHD. 相似文献
Design: A quasi-experimental design with 65 preadolescents diagnosed with ADD or ADHD in an upper-middle class community in the United States.
Methods: Participants randomly assigned to either the control or experimental group completed Harter's Self-Perception Profile for Children instrument at the beginning of the study and 4 weeks later. Students in the experimental condition participated in a school-nurse facilitated support group which met twice weekly for 4 weeks.
Findings: Participants in the support group had increased scores on each of the six subscales, with significant increases on four of the subscales, including perceived social acceptance, perceived athletic competence, perceived physical appearance, and perceived global self-worth.
Conclusion: Participation in a school-based, nurse-led support group was positively associated with perception of self-worth in preadolescents diagnosed with ADD or ADHD. 相似文献
5.
Christopher M Jewell Melissa E Hays Yukishige Kondo Nicholas L Abbott David M Lynn 《Journal of controlled release》2006,112(1):129-138
The ability of two redox-active, ferrocene-containing cationic lipids [11-(ferrocenylundecyl)trimethylammonium bromide (FTMA) and bis(11-ferrocenylundecyl)dimethylammonium bromide (BFDMA)] to transfect mammalian cells was investigated. This study sought to determine the range of conditions over which these lipids were capable of transfecting cells and whether the oxidation state of the ferrocenyl groups in these materials could be used to influence the extent of transfection. Experiments conducted in the COS-7 cell line demonstrated that reduced and oxidized FTMA were substantially cytotoxic and did not transfect cells. Subsequent experiments conducted using BFDMA and reporter plasmids encoding enhanced green fluorescent protein (EGFP) and firefly luciferase demonstrated that BFDMA was able to transfect cells. However, the extent of transfection depended significantly upon both the concentration of BFDMA and the oxidation state of the lipid. Quantitative characterization of cytotoxicity and gene expression demonstrated that a window of concentration existed over which reduced BFDMA was non-cytotoxic and yielded high levels of transfection, but over which electrochemically oxidized BFDMA yielded very low (background) levels of transfection. Characterization of lipoplexes using dynamic light scattering demonstrated that reduced and oxidized BFDMA formed small aggregates (ca. 90 to 250nm) at concentrations of lipid ranging from 2 to 10 microM. Taken together, these results demonstrate that the oxidation state of BFDMA, which can be controlled electrochemically, can be used to control the extent of cell transfection. These results could form the basis of transfection procedures that exploit the redox behavior of ferrocene-containing lipids to achieve active spatial and temporal control over transfection using electrochemical methods. 相似文献
6.
Various forms of signal processing are used in modern ASP hearing aids. The present study investigated the relationship between sentence recognition ability and two types of signal processing used in commercially available hearing aids. Results indicated a significant improvement in sentence recognition ability employing an instrument with adaptive compression (variable release time) versus an instrument with an adaptive high-pass filter with short attack and release times. Data were obtained for a single-talker competing message at several message-to-competition ratios. The adaptive compression system may prove to be beneficial to hearing-impaired listeners in certain background noise environments. 相似文献
7.
Thomas J Birk Rodger D MacArthur Lynn M Lipton Sheldon D Levine 《The Journal of the Association of Nurses in AIDS Care》2002,13(6):20-24
The purpose of this study was to determine whether blood lipid and lipoprotein concentrations varied in 5 men with advanced HIV-1 infection after 12 months of aerobic exercise training. Prior to exercise, the mean baseline cholesterol and high-density lipoprotein cholesterol (HDL-C) serum concentration were each lower, and mean baseline triglyceride concentration was higher compared to a healthy population norm. Consistent exercise training for 12 months failed to significantly (p > .05) alter cholesterol or HDL-C. Triglyceride concentration was significantly (p < .05) elevated above baseline (63 mg/dL) regardless of exercise compliance. The results suggest that long-term exercise training cannot correct lipid profile abnormality, particularly hypertriglyceridemia, common to individuals with advanced HIV-1 infection. 相似文献
8.
9.
Pradip K. Rustagi Tin Han Lynn Ziolkowski Deborah L. Farolino Mark S. Currie Gerald L. Logue 《British journal of haematology》1987,66(4):461-465
The anti-granulocyte activity of serum from patients with B-cell chronic lymphocytic leukaemia (CLL) and other lymphoproliferative disorders was investigated. Granulocyte-binding IgG was measured in 34 patients with CLL, 13 patients with hairy cell leukaemia, one patient with prolymphocytic leukaemia, two patients with Sézary cell leukaemia, and seven patients with chronic T-cell lymphocytosis who had a predominance of circulating large granular lymphocytes. Anti-granulocyte activity was absent in CLL and its variants, but present in the majority of granulocytopenic patients with chronic T-cell lymphocytosis. In one of these patients, granulocytopenia was associated with complement-activating IgG granulocyte antibody. Thus, antibody-mediated granulocyte injury appears to be an unusual occurrence in chronic lymphocytic leukaemia, but is a frequent complication of chronic T-cell lymphocytosis. 相似文献
10.
M. Laurin Council Jennifer M. Gardner Cynthia Helms Ying Liu Lynn A. Cornelius Anne M. Bowcock 《Experimental dermatology》2009,18(5):485-487
Abstract: The risks of developing malignant melanoma (MM) include ultraviolet irradiation and genetic factors. To examine the contribution of rare and common variation within known MM genes in sporadic US MM patients, coding regions of known MM susceptibility genes [cyclin-dependent kinase inhibitor 2A ( CDKN2A ), cyclin-dependent kinase 4, melanocortin 1 receptor ( MC1R ) and tyrosinase ( TYR )] were resequenced in 109–135 MM cases. The significance of variants was examined by comparing their frequencies in 390 cancer-free controls. Potential deleterious mutations in CDKN2A were found in two patients and two others had variants of unknown significance. Cases were more likely than controls to harbour the MC1R 'R' variants known or predicted to alter its function ( P = 0.002), particularly the R160W variant ( P = 0.0035). The associated TYR R402Q variant (rs1126809*A) was found in 29% of cases, similar to what has been described previously. One MM patient with a family history of MM, who had developed other skin cancers, was homozygous for a novel TYR variant (P406L) of unknown significance. Hence, rare variants in TYR may be important risk factors for skin cancer. 相似文献