全文获取类型
收费全文 | 2253篇 |
免费 | 209篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 7篇 |
儿科学 | 88篇 |
妇产科学 | 119篇 |
基础医学 | 262篇 |
口腔科学 | 19篇 |
临床医学 | 186篇 |
内科学 | 368篇 |
皮肤病学 | 12篇 |
神经病学 | 226篇 |
特种医学 | 128篇 |
外科学 | 449篇 |
综合类 | 38篇 |
预防医学 | 191篇 |
眼科学 | 22篇 |
药学 | 211篇 |
肿瘤学 | 164篇 |
出版年
2022年 | 16篇 |
2021年 | 20篇 |
2020年 | 14篇 |
2018年 | 25篇 |
2017年 | 25篇 |
2016年 | 21篇 |
2015年 | 24篇 |
2014年 | 43篇 |
2013年 | 81篇 |
2012年 | 82篇 |
2011年 | 101篇 |
2010年 | 80篇 |
2009年 | 55篇 |
2008年 | 77篇 |
2007年 | 92篇 |
2006年 | 73篇 |
2005年 | 82篇 |
2004年 | 70篇 |
2003年 | 60篇 |
2002年 | 74篇 |
2001年 | 74篇 |
2000年 | 82篇 |
1999年 | 77篇 |
1998年 | 46篇 |
1997年 | 39篇 |
1996年 | 37篇 |
1995年 | 37篇 |
1994年 | 26篇 |
1993年 | 30篇 |
1992年 | 59篇 |
1991年 | 72篇 |
1990年 | 65篇 |
1989年 | 66篇 |
1988年 | 81篇 |
1987年 | 67篇 |
1986年 | 73篇 |
1985年 | 62篇 |
1984年 | 37篇 |
1983年 | 25篇 |
1982年 | 21篇 |
1981年 | 21篇 |
1980年 | 21篇 |
1979年 | 25篇 |
1978年 | 21篇 |
1977年 | 29篇 |
1976年 | 25篇 |
1975年 | 16篇 |
1974年 | 28篇 |
1973年 | 13篇 |
1969年 | 14篇 |
排序方式: 共有2490条查询结果,搜索用时 15 毫秒
41.
42.
OBJECTIVES: To determine the spectrum of N and G genotypes of respiratory syncytial virus (RSV) causing respiratory tract infection and whether particular genotypes are associated with severity of infection. PATIENTS AND METHODS: Nasopharyngeal aspirates (NPAs) were obtained from 114 infants with acute respiratory tract infection due to RSV over two seasons. Viral mRNA was extracted from NPAs or cultured virus, reverse transcribed, and the cDNA amplified by the polymerase chain reaction using primers directed to parts of the N and G gene respectively. Amplicons were separately digested with four different restriction endonucleases for each gene. The fragments were separated by agarose gel, electrophoresis, and the electrophoretic patterns used to assign the various genotypes. Disease severity was assessed as very mild (upper respiratory tract signs only), mild (coryza and signs of lower respiratory tract infection), moderate (requiring nasogastric or intravenous fluids), and severe (requiring oxygen or ventilation). RESULTS: Five of the six known N genotypes were detected, but NP4 and NP2 were found most frequently. There was no association between N genotype and disease severity. Six G (SHL) genotypes were detected. Significantly (p = 0.04) more of the infants infected with the SHL2 genotype had severe or moderate disease. CONCLUSIONS: During the seasonal peaks of RSV respiratory tract infection at least 10 different RSV genotypes cocirculated. While there is no association between N genotypes and disease severity, infection with the SHL2 G genotype appears to result in moderate to severe disease. 相似文献
43.
Glucocorticoid and Fas ligand induced mucosal lymphocyte apoptosis after burn injury 总被引:4,自引:0,他引:4
Fukuzuka K Edwards CK Clare-Salzer M Copeland EM Moldawer LL Mozingo DW 《The Journal of trauma》2000,49(4):710-716
BACKGROUND: The purpose of this study was to examine the effects of a steam burn injury on apoptosis in gut-associated lymphoid tissue and to determine whether endogenous glucocorticoid and Fas ligand signaling were involved in this process. METHODS: Histologic analysis, in situ deoxynucleotidyl transferase dUTP nick-end labeling staining and annexin V and 7-amino-actinomycin-D flow cytometry of lymphocyte populations were evaluated in intraepithelial lymphocytes and Peyer's patch. Additional mice were pretreated with a glucocorticoid receptor antagonist (mifepristone) before the steam burn. Similarly, C3H/HeJ-FasL(gld) mice lacking functional Fas ligand were also studied. RESULTS: Apoptosis was significantly increased in intraepithelial lymphocytes and Peyer's patch after the burn injury. Mifepristone pretreatment significantly reduced apoptosis in both T- and B-cell populations in intraepithelial lymphocytes after the burn injury. In contrast, the increased apoptosis seen in B-cells from Peyer's patch was not seen in C3H/HeJFasL(gld) mice, whereas the increased apoptosis in CD8+ T-cells was unaffected. CONCLUSION: Both corticosteroids and FasL contribute to the apoptosis in gut-associated lymphoid tissues early after burn injury. 相似文献
44.
45.
Feasibility and acceptability of a motivational interviewing breastfeeding peer support intervention
Lauren Copeland Laura Merrett Cheryl McQuire Aimee Grant Nina Gobat Sally Tedstone Rebecca Playle Sue Channon Julia Sanders Rhiannon Phillips Billie Hunter Amy Brown Deborah Fitzsimmons Michael Robling Shantini Paranjothy 《Maternal & child nutrition》2019,15(2)
An uncontrolled study with process evaluation was conducted in three U.K. community maternity sites to establish the feasibility and acceptability of delivering a novel breastfeeding peer‐support intervention informed by motivational interviewing (MI; Mam‐Kind). Peer‐supporters were trained to deliver the Mam‐Kind intervention that provided intensive one‐to‐one peer‐support, including (a) antenatal contact, (b) face‐to‐face contact within 48 hr of birth, (c) proactive (peer‐supporter led) alternate day contact for 2 weeks after birth, and (d) mother‐led contact for a further 6 weeks. Peer‐supporters completed structured diaries and audio‐recorded face‐to‐face sessions with mothers. Semistructured interviews were conducted with a purposive sample of mothers, health professionals, and all peer‐supporters. Interview data were analysed thematically to assess intervention acceptability. Audio‐recorded peer‐support sessions were assessed for intervention fidelity and the use of MI techniques, using the MITI 4.2 tool. Eight peer‐supporters delivered the Mam‐Kind intervention to 70 mothers in three National Health Service maternity services. Qualitative interviews with mothers (n = 28), peer‐supporters (n = 8), and health professionals (n = 12) indicated that the intervention was acceptable, and health professionals felt it could be integrated with existing services. There was high fidelity to intervention content; 93% of intervention objectives were met during sessions. However, peer‐supporters reported difficulties in adapting from an expert‐by‐experience role to a collaborative role. We have established the feasibility and acceptability of providing breastfeeding peer‐support using a MI‐informed approach. Refinement of the intervention is needed to further develop peer‐supporters' skills in providing mother‐centred support. The refined intervention should be tested for effectiveness in a randomised controlled trial. 相似文献
46.
Combination gemcitabine, platinum, and bevacizumab for the treatment of recurrent ovarian cancer 总被引:1,自引:1,他引:0
Richardson DL Backes FJ Seamon LG Zanagnolo V O'Malley DM Cohn DE Fowler JM Copeland LJ 《Gynecologic oncology》2008,111(3):461-466
ObjectiveTo describe the response rate (RR), progression-free survival (PFS), and toxicity profile of combination gemcitabine, platinum, and bevacizumab (GPB) for the treatment of recurrent epithelial ovarian cancer (EOC).MethodsA chart review of all patients with recurrent EOC who were treated with D1, D15 GPB in a 28-day cycle at a single institution was performed. Standard doses were gemcitabine 1000 mg/m2, cisplatin 30 mg/m2 or carboplatin AUC 3, and bevacizumab 10 mg/kg. All patients were analyzed for toxicity. RR and PFS were assessed in all patients who received at least 2 cycles of GPB.ResultsThirty-five patients were identified, and 33 received at least 2 cycles of GPB. The majority of patients (80%) were platinum sensitive. Patients received a median of 6 cycles of GPB (range 1–24). Sixteen patients (48%) had a complete response (CR), and 10 patients (30%) had a partial response (PR), for a total RR of 78%. An additional 5 patients (15%) had stable disease, and only 2 (6%) patients had progressive disease. The median overall PFS was 12 months (95% CI 7–15), with a median follow-up time of 10 months (2–22). Two patients (6%) had bowel perforations, and both survived. Hematologic toxicities were most common, with 29% and 14% of patients experiencing grade 3 or 4 neutropenia and thrombocytopenia respectively.ConclusionsThe combination of GPB demonstrated excellent efficacy for the treatment of recurrent EOC. However, serious toxicities occurred, and the safety profile of this combination requires further study. 相似文献
47.
48.
Murray M. Copeland 《Postgraduate medicine》2013,125(4):402-404
Dr. Copeland describes the development of The American Joint Committee on Cancer Staging and End Results Reporting, its objectives, and the steps in the preparation of the clinical classifications. Emphasis is on simplicity, practicability and credibility. The TNM (tumor, nodes, metastasis) system is utilized where possible. 相似文献
49.
Darcy A. Copeland 《Issues in mental health nursing》2013,34(9):943-975
A review of literature concerning familial violence and mental illness using the Vulnerable Populations Conceptual Model (VPCM) as an organizing framework is presented. Since family members are most likely to be targets if a person who is mentally ill becomes violent, this review emphasizes the VPCM concepts of resource availability (including capital, stigma, and access to healthcare), risk, and health status of those family members. The population-based VPCM was used in an attempt to move the examination of this phenomenon from a focus on the individual to a conceptualization of it as family violence occurring within a broader, social context. 相似文献
50.