全文获取类型
收费全文 | 4276篇 |
免费 | 353篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 154篇 |
儿科学 | 139篇 |
妇产科学 | 151篇 |
基础医学 | 551篇 |
口腔科学 | 48篇 |
临床医学 | 500篇 |
内科学 | 677篇 |
皮肤病学 | 23篇 |
神经病学 | 415篇 |
特种医学 | 85篇 |
外科学 | 515篇 |
综合类 | 79篇 |
一般理论 | 11篇 |
预防医学 | 525篇 |
眼科学 | 63篇 |
药学 | 317篇 |
肿瘤学 | 385篇 |
出版年
2023年 | 32篇 |
2022年 | 58篇 |
2021年 | 114篇 |
2020年 | 106篇 |
2019年 | 136篇 |
2018年 | 143篇 |
2017年 | 105篇 |
2016年 | 124篇 |
2015年 | 145篇 |
2014年 | 187篇 |
2013年 | 233篇 |
2012年 | 403篇 |
2011年 | 355篇 |
2010年 | 173篇 |
2009年 | 138篇 |
2008年 | 248篇 |
2007年 | 261篇 |
2006年 | 247篇 |
2005年 | 253篇 |
2004年 | 221篇 |
2003年 | 207篇 |
2002年 | 157篇 |
2001年 | 49篇 |
2000年 | 40篇 |
1999年 | 49篇 |
1998年 | 39篇 |
1997年 | 16篇 |
1996年 | 20篇 |
1995年 | 18篇 |
1994年 | 10篇 |
1993年 | 12篇 |
1992年 | 22篇 |
1991年 | 25篇 |
1990年 | 18篇 |
1989年 | 22篇 |
1988年 | 16篇 |
1987年 | 20篇 |
1986年 | 12篇 |
1985年 | 13篇 |
1984年 | 10篇 |
1983年 | 11篇 |
1982年 | 18篇 |
1981年 | 14篇 |
1980年 | 19篇 |
1979年 | 11篇 |
1978年 | 10篇 |
1977年 | 10篇 |
1976年 | 11篇 |
1973年 | 13篇 |
1972年 | 11篇 |
排序方式: 共有4638条查询结果,搜索用时 0 毫秒
1.
Postpartum fatigue is a normal condition that most women experience. Breastfeeding is often associated in women's minds as contributing to the feeling of overall perceived fatigue, and many women indicate that they have ceased breastfeeding because of fatigue. However, the relationship between feeding choice and perceived fatigue has never been established. Two hundred and fifty-three women participated in a study examining whether perceived fatigue differed for bottle-feeding and breastfeeding women at 3 different times during the postpartum period (2-4 days, 6 weeks, and 12 weeks postpartum). Results showed no significant differences for these 2 groups, suggesting that perceived fatigue during the postpartum period is not dependent on feeding choice. Additional analyses examining other variables with a potential effect were nonsignificant. Because perceived physical fatigue does not appear to be dependent on feeding choice, women should be prepared for the feeling of perceived fatigue during the postpartum period while at the same time be reassured that feeding choice is not correlated. 相似文献
2.
3.
4.
Although information regarding attitudes and characteristics of human blood donors has been researched, little is known about the motivations and demographic and personality characteristics of women who choose to donate their breast milk. Eight milk banks in France participated in a study examining donor characteristics, providing data on 103 women. The results showed that the donors were women of average childbearing age with strong support at home. Almost half did not work outside of the home, compared to the national average of 80% of women in this age group; similarly, a large number (currently working or not) were from the health and social services fields. Reasons for donation were largely altruistic, and a general optimistic attitude prevailed within the participants. The results of this study provide useful information for the recruitment of potential donors as well as information on how to facilitate and provide optimal service through milk donation. 相似文献
5.
6.
The role of growth factors and cytokines in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine whether changes in the amount and location of cytokines and growth factors may be associated with impaired healing in chronic leg ulcers. Biopsies from leg ulcers of 21 patients and from normal skin of nine healthy volunteers were examined immunohistochemically for selected growth factors and cytokines. Greater staining intensity was found in keratinocytes at the edges of ulcers compared to normal skin, or skin adjacent to the ulcers. Staining at the ulcer edge was more intense in nonhealing ulcers for only vascular endothelial growth factor and platelet-derived growth factor, whereas staining in the adjacent skin was more intense for all factors in the nonhealing phase. For all factors staining was cytoplasmic, suggesting production in these areas. This study shows up-regulation of the production of cytokines and growth factors in keratinocytes of chronic leg ulcers that is greater when the ulcers are nonhealing. 相似文献
7.
Dawn Stacey RN MScN CON Annette M. O'Connor RN PhD † Cathy DeGrasse RN MScN ‡ Shailendra Verma MD FRCP § 《Health expectations》2003,6(1):3-18
Objective To develop and evaluate the effectiveness of a breast cancer prevention decision aid for women aged 50 and older at higher risk of breast cancer. Design Pre‐test–post‐test study using decision aid alone and in combination with counselling. Setting Breast Cancer Risk Assessment Clinic. Participants Twenty‐seven women aged 50–69 with 1.66% or higher 5‐year risk of breast cancer. Intervention Self‐administered breast cancer prevention decision aid. Main outcome measures Acceptability; decisional conflict; knowledge; realistic expectations; choice predisposition; intention to improve life‐style practices; psychological distress; and satisfaction with preparation for consultation. Results The decision aid alone, or in combination with counselling, decreased some dimensions of decisional conflict, increased knowledge (P < 0.01), and created more realistic expectations (P < 0.01). The aid in combination with counselling, significantly reduced decisional conflict (P < 0.01) and psychological distress (P < 0.02), helped the uncertain become certain (P < 0.02), and increased intentions to adopt healthier life‐style practices (P < 0.03). Women rated the aid as acceptable, and both women and practitioners were satisfied with the effect it had on the counselling session. Conclusion The decision aid shows promise as a useful decision support tool. Further research should compare the effect of the decision aid in combination with counselling to counselling alone. 相似文献
8.
Stacey M Pollock-Barziv Anne I Dipchand Brian W McCrindle Nadya Nalli Lori J West 《The Journal of heart and lung transplantation》2005,24(2):190-194
BACKGROUND: While Tacrolimus (Tac) and Cyclosporine (Cya) immunosuppression are used after cardiac transplantation (tx), few studies have evaluated their use in pediatric patients. METHODS: We randomized 26 heart transplant recipients (pts) in a prospective, open-label trial to Tac (n = 14) or Cya (n = 12) to compare their efficacy and side-effects. Mean age at tx was 4.2 years for Tac and 5.8 years for Cya. Mean follow-up was 26 months (range: 11-39 months) for Tac and 24 months for Cya (range: 33-13 months). RESULTS: Our data suggest that both regimens are efficacious in the pediatric population. Conversion from Cya to Tac was useful for dealing with persistent rejection, although this sample did not suggest lower incidence of acute cellular rejection in the Tac group. CONCLUSIONS: Further studies are required to establish pharmacokinetic parameters to enhance therapeutic monitoring of these patients to minimize side effects and enhance outcomes. 相似文献
9.
The Stiles-Crawford effect of the first kind (SCE-I) was measured on both emmetropic and myopic subjects at six different retinal locations. The results revealed a number of significant discrepancies in receptor alignment between the groups of different refractive errors. In myopic subjects, the receptors in the nasal retina (i.e. between the fovea and the optic nerve head) were found to be aligned nasally towards the optic nerve head, whereas the receptors in the temporal retina were aligned towards the centre of the exit pupil. In emmetropic subjects, the receptors across the retina were finely tuned towards the centre of the exit pupil. The magnitude of the receptor displacement in myopic subjects was found to be directly associated with the length of the eyeball. 相似文献
10.
Jamie A Koufman Catherine J Rees William D Frazier Lauren A Kilpatrick S Carter Wright Stacey L Halum Gregory N Postma 《Otolaryngology--head and neck surgery》2007,137(1):146-151
BACKGROUND: Unsedated office-based laser surgery (UOLS) of the larynx and trachea has significantly improved the treatment options for patients with laryngotracheal pathology including recurrent respiratory papillomas, granulomas, leukoplakia, and polypoid degeneration. UOLS delivered by flexible endoscopes has dramatically impacted office-based surgery by reducing the time, costs, and morbidity of surgery. OBJECTIVES: To review our experience with 443 laryngotracheal cases treated by UOLS. METHODS: The laser logbooks at the Center for Voice and Swallowing Disorders were reviewed for UOLS, and the medical and laryngological histories were detailed, as were the treatment modalities, frequencies, and complications. RESULTS: Of the 443 cases, 406 were performed with the pulsed-dye laser, 10 with the carbon-dioxide laser, and 27 with the thulium: yttrium-aluminum-garnet laser. There were no significant complications in this series. A review of indications and wavelength selection criteria is presented. CONCLUSION: Unsedated, office-based, upper aerodigestive tract laser surgery appears to be a safe and effective treatment option for many patients with laryngotracheal pathology. 相似文献