全文获取类型
收费全文 | 38787篇 |
免费 | 2491篇 |
国内免费 | 97篇 |
专业分类
耳鼻咽喉 | 448篇 |
儿科学 | 1434篇 |
妇产科学 | 945篇 |
基础医学 | 4731篇 |
口腔科学 | 462篇 |
临床医学 | 6453篇 |
内科学 | 6716篇 |
皮肤病学 | 401篇 |
神经病学 | 3723篇 |
特种医学 | 799篇 |
外国民族医学 | 1篇 |
外科学 | 3574篇 |
综合类 | 362篇 |
一般理论 | 49篇 |
预防医学 | 5501篇 |
眼科学 | 403篇 |
药学 | 2362篇 |
中国医学 | 44篇 |
肿瘤学 | 2967篇 |
出版年
2024年 | 30篇 |
2023年 | 323篇 |
2022年 | 449篇 |
2021年 | 847篇 |
2020年 | 602篇 |
2019年 | 938篇 |
2018年 | 1092篇 |
2017年 | 812篇 |
2016年 | 851篇 |
2015年 | 945篇 |
2014年 | 1328篇 |
2013年 | 2093篇 |
2012年 | 3033篇 |
2011年 | 3213篇 |
2010年 | 1711篇 |
2009年 | 1550篇 |
2008年 | 2783篇 |
2007年 | 2792篇 |
2006年 | 2732篇 |
2005年 | 2685篇 |
2004年 | 2473篇 |
2003年 | 2196篇 |
2002年 | 2107篇 |
2001年 | 234篇 |
2000年 | 199篇 |
1999年 | 266篇 |
1998年 | 434篇 |
1997年 | 337篇 |
1996年 | 260篇 |
1995年 | 209篇 |
1994年 | 216篇 |
1993年 | 208篇 |
1992年 | 128篇 |
1991年 | 115篇 |
1990年 | 92篇 |
1989年 | 99篇 |
1988年 | 90篇 |
1987年 | 79篇 |
1986年 | 83篇 |
1985年 | 82篇 |
1984年 | 99篇 |
1983年 | 76篇 |
1982年 | 90篇 |
1981年 | 99篇 |
1980年 | 70篇 |
1979年 | 41篇 |
1978年 | 31篇 |
1977年 | 38篇 |
1976年 | 21篇 |
1975年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
81.
Margaret J. Harrison Kaysi Eastlick Kushner Karen Benzies Gwen Rempel Cathy Kimak 《分娩》2003,30(2):109-115
ABSTRACT: Background: Increasingly, women seek involvement in decisions about their health care. The purpose of this study was to examine women's experience of, and satisfaction with, their involvement in health care decisions during a high‐risk pregnancy. Methods: Forty‐seven women with hypertension or threatened preterm delivery (including multiple births) were interviewed after the birth of their child. They received prenatal care at home from nurses in a community program or were hospitalized. The in‐depth interviews were audiotaped and transcribed; data were analyzed using constant comparative methods. Results: Women identified an increased feeling of responsibility for the health of their baby and themselves, but differed in choosing active or passive involvement in health care decisions. Women who wanted active involvement achieved it through one of three processes: struggling for, negotiating, or being encouraged. Women who wanted passive involvement and women facing health crises used the process of trusting in the expertise of nurses and physicians. Women were satisfied if the care from health care professionals was congruent with how they wanted to be involved in decision‐making. Conclusions: Although most women want to be actively involved in health decision‐making during a high‐risk pregnancy, some prefer a passive role. The setting of prenatal care, community‐based or in‐hospital, was less important than the ability of nurses and physicians to support the woman in her preferred role in decision‐making. (BIRTH 30:2 June 2003) 相似文献
82.
James F. Meschia Edward Junkins Karen J. Hofman 《American journal of medical genetics. Part A》1992,44(5):664-667
Epidermal nevi are typically congenital but rarely familial. We report on a family in which 3 relatives have systematized epidermal nevi. The propositus also has evidence of a hemangioma and a hemangioendothelioma. Peripheral blood and skin fibroblast karyotypes of the propositus did not show evidence of mosaicism. Epidermal nevi have been associated with nondermatologic pathology, involving the nervous, vascular, and skeletal systems in sporadic cases. This report demonstrates that nondermatologic pathology can be also be associated with systematized epidermal nevi in a familial setting. The apparent skipping of generations may be explained by autosomal dominant inheritance with decreased penetrance. © 1992 Wiley-Liss, Inc. 相似文献
83.
Francisco M. Averhoff Edward Brink Bette Pollard Karen Resha Gloria Bryan Margaret V. Vaillancourt 《The Journal of school health》1997,67(7):304-308
ABSTRACT: On March 11–12, 1996, a workshop on how to implement new adolescent immunization (AI) recommendations was held in Atlanta, Ga. Sponsored by the Centers for Disease Control and Prevention, it was a collaborative effort of the National Immunization Program, the Division of Adolescent and School Health/National Center for Chronic Disease Prevention and Health Promotion, and the Hepatitis Branch/National Center for Infectious Diseases. The workshop brought together organizations and individuals interested in adolescent health and immunizations so they could address how new Al recommendations can be implemented most effectively. This article offers an overview of their discussions and suggestions, including issues of cooperation, education, legislation, and Al program development among health provider organizations, health departments, schools, community groups and various other agencies relating to adolescent health services. 相似文献
84.
Dr. Harvey I. Pass MD Karen Kranda RN Barbara K. Temeck MD Irwin Feuerstein MD Seth M. Steinberg PhD 《Annals of surgical oncology》1997,4(3):215-222
Background: We analyzed morbidity and mortality, sites of recurrence, and possible prognostic factors in 95 (78 male, 17 female) patients
with MPM on phase I–III trials since 1990. A debulking resection to a requisite, residual tumor thickness of ≤ 5 mm was required
for inclusion.
Methods: Preoperative tumor volumes were determined by three-dimensional reconstruction of chest computerized tomograms. Pleurectomy
(n=39) or extrapleural pneumonectomy (EPP; n=39) was performed. Seventeen patients could not be debulked. Preoperative EPP
platelet counts (404,000) and mean tumor volume (491 cm3) were greater than that seen for pleurectomy (344,000, 114 cm3).
Results: Median survival for all patients was 11.2 months, with that for pleurectomy 14.5 months, that for EPP 9.4 months, and that
for unresectable patients 5.0 months. Arrhythmia (n=14; 15%) was the most common complication, and there were two deaths related
to surgery (2.0%). Tumor volume of >100 ml, biphasic histology, male sex, and elevated platelet count were associated with
decreased survival (p<0.05). Both EPP and pleurectomy had equivalent recurrence rates (27 of 39 [69%] and 31 of 39 [79%],
respectively); however, 17 of 27 EPP recurrences as opposed to 28 of 31 pleurectomy recurrences were locoregional (p2=0.013).
Conclusions: Debulking resections for MPM can be performed with low operative mortality. Size and platelet count are important preoperative
prognostic parameters for MPM. Patients with poor prognostic indicators should probably enter nonsurgical, innovative trials
where toxicity or response to therapy can be evaluated.
Presented at the 49th Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996. 相似文献
85.
Jill Macleod Clark PhD BSc RGN Jill Maben MSc BA RGN Karen Jones BA RHV RGN 《Journal of advanced nursing》1997,26(1):161-168
This is the first of two papers which address aspects of the findings of a large scale study commissioned by the English National Board which set out to examine the impact of Project 2000 on perceptions of the philosophy and practice of nursing. The findings presented here suggest that there have been fundamental shifts in perceptions of the nature and discipline of nursing. Students and diplomates of the course perceive themselves as knowledgeable doers, with their practice well grounded in theory and research. They value the interpersonal skills teaching and place the patient firmly at the centre of care delivery, viewing the patient holistically and being prepared to be fierce patient advocates where necessary. It is difficult to determine the extent to which these shifts can be attributed to the Project 2000 course, although the Project 2000 approach to education appears to be an important factor. 相似文献
86.
87.
Lorien Abroms Cynthia M Jorgensen Brian G Southwell Alan C Geller Karen M Emmons 《Health education & behavior》2003,30(1):29-43
This study employs focus group methodology to explore gender differences in sunscreen use. Guided by the theory of reasoned action, males and females were found to differ on each of the following constructs: behavior, behavioral beliefs, and normative beliefs. Males and females differed in their sunscreen use, with females adopting a more preventive style of sunscreen use and males a more reactive style. Males and females differed in their salient beliefs that motivated their sunscreen use, many of which were related to traditional American gender roles. In addition, although males and females were aware of both positive and negative sources of normative beliefs regarding sunscreen use, females received more encouragement from their mothers and peers than males. Findings are discussed in terms of their implications for the design of future interventions. 相似文献
88.
Multiplex PCR analysis of in vivo-arising deletion mutations in the hprt gene of human T-lymphocytes
James C. Fuscoe Lisa J. Zimmerman Karen Harrington-Brock Martha M. Moore 《Environmental and molecular mutagenesis》1994,23(2):89-95
A multiplex polymerase chain reaction (PCR) procedure was adapted for the rapid and efficient evaluation of deletions of the hypoxanthine guanine phosphoribosyltransferase (hprt) gene in human T-lymphocytes. The hprt clonal assay was used to isolate in vivo-arising hprt-deficient T-cells from six healthy males. Mutant frequencies ranged from 9-27 × 10?6. Simple crude cellular extracts from 223 mutants were analyzed for hprt gene deletion. Sixteen (7.2%) were found to be due to total gene deletion and 22 (9.9%) were due to partial gene deletion. The relatively high frequency of total gene deletions was caused by replicate isolates of a single mutational event as shown by single-strand conformation polymorphism (SSCP) analysis of rearranged T-cell receptor (TCR)-γ genes. Eighteen of the 22 partial hprt gene deletion mutants were determined to be of independent origin based on a unique hprt mutation or SSCP-TCR-γ pattern. One-half (9/18) of the partial deletion mutants involved all or part of exon 4 alone, suggesting that this region of the hprt gene is prone to deletion. The small deletions effecting exon 1 (1 mutant), exon 2 (2 mutants), and exon 4 (6 mutants) would not have been detected by conventional Southern blot analysis and may represent a new, previously unrecognized class of mutations. The ready isolation of such intragenic deletions will allow the characterization of breakpoint junctions and may provide insights into the important processes of DNA breakage and rejoining. © 1994 Wiley-Liss, Inc. 相似文献
89.
90.
David F Kroon M Louise Lawson Craig S Derkay Karen Hoffmann Joe McCook 《Otolaryngology--head and neck surgery》2002,126(5):499-504
OBJECTIVE: The study goal was to demonstrate the prevalence and severity of external auditory exostoses (EAEs) in a population of surfers and to examine the relationship between these lesions and the length of time surfed as well as water temperature in which the swimmers surfed. It was hypothesized that subjects who predominantly surfed in colder waters had more frequent and more severe exostoses. METHODS: Two hundred two avid surfers (91% male and 9% female, median age 17 years) were included in the study. EAEs were graded based on the extent of external auditory canal patency; grades of normal (100% patency), mild (66% to 99% patency), and moderate-severe (<66% patency) were assigned. Otoscopic findings were correlated with data collected via questionnaires that detailed surfing habits. RESULTS: There was a 38% overall prevalence of EAEs, with 69% of lesions graded as mild and 31% graded as moderate-severe. Professional surfers (odds ratio 3.8) and those subjects who surfed predominantly in colder waters (odds ratio 5.8) were found to be at a significantly increased risk for the development of EAEs. The number of years surfed was also found to be significant, increasing one's risk for developing an exostosis by 12% per year and for developing more severe lesions by 10% per year. Individuals who had moderate-severe EAEs were significantly more likely to be willing to surf in colder waters than were those who had mild EAEs (odds ratio 4.3). CONCLUSIONS: EAEs are more prevalent in cold water surfers, and additional years surfing increase one's risk not only for developing an EAE but also for developing more severe lesions. 相似文献