全文获取类型
收费全文 | 272816篇 |
免费 | 37258篇 |
国内免费 | 3466篇 |
专业分类
耳鼻咽喉 | 6855篇 |
儿科学 | 7178篇 |
妇产科学 | 4221篇 |
基础医学 | 23061篇 |
口腔科学 | 4522篇 |
临床医学 | 37701篇 |
内科学 | 68761篇 |
皮肤病学 | 11172篇 |
神经病学 | 24575篇 |
特种医学 | 13392篇 |
外科学 | 56308篇 |
综合类 | 757篇 |
现状与发展 | 75篇 |
一般理论 | 27篇 |
预防医学 | 13505篇 |
眼科学 | 6440篇 |
药学 | 12215篇 |
中国医学 | 1460篇 |
肿瘤学 | 21315篇 |
出版年
2024年 | 740篇 |
2023年 | 5525篇 |
2022年 | 3839篇 |
2021年 | 7343篇 |
2020年 | 7908篇 |
2019年 | 4990篇 |
2018年 | 10781篇 |
2017年 | 10055篇 |
2016年 | 11971篇 |
2015年 | 13446篇 |
2014年 | 21367篇 |
2013年 | 22585篇 |
2012年 | 16407篇 |
2011年 | 15973篇 |
2010年 | 16133篇 |
2009年 | 19113篇 |
2008年 | 13063篇 |
2007年 | 10975篇 |
2006年 | 12749篇 |
2005年 | 9571篇 |
2004年 | 8086篇 |
2003年 | 6405篇 |
2002年 | 5870篇 |
2001年 | 6764篇 |
2000年 | 5748篇 |
1999年 | 5293篇 |
1998年 | 4499篇 |
1997年 | 4099篇 |
1996年 | 3842篇 |
1995年 | 3637篇 |
1994年 | 2308篇 |
1993年 | 1884篇 |
1992年 | 2106篇 |
1991年 | 2085篇 |
1990年 | 1684篇 |
1989年 | 1717篇 |
1988年 | 1467篇 |
1987年 | 1309篇 |
1986年 | 1208篇 |
1985年 | 1076篇 |
1984年 | 803篇 |
1983年 | 705篇 |
1982年 | 643篇 |
1981年 | 565篇 |
1980年 | 485篇 |
1979年 | 526篇 |
1978年 | 489篇 |
1977年 | 513篇 |
1975年 | 397篇 |
1972年 | 409篇 |
排序方式: 共有10000条查询结果,搜索用时 11 毫秒
951.
Margret S. Magid Wallace G. Campbell Jr MD Sutini Ngadiman Thomas A. Godwin MD Robert Ward 《Fetal and pediatric pathology》1997,17(2):303-314
We report a case of an infantile myofibromatosis with hemangiopericytoma-like features arising in the tongue of a 5-month-old female infant. Many authors now classify neoplasms as infantile myofibromatosis that were previously called infantile hemangiopericytoma. The ultrastructural features of our tumor illustrate its biphasic nature and provide a possible explanation for its histogenesis. Infantile myofibromatosis, including those diagnosed as infantile hemangiopericytomas, rarely arise in any intraoral location. Despite the generally good prognosis associated with these neoplasms, complete surgical excision is recommended to avoid recurrences. 相似文献
952.
E. Alsat PhD J. Guibourdenche PhD D. Luton MD F. Frankenne PhD D. Evain-Brion MD PhD 《American journal of obstetrics and gynecology》1997,177(6):1526-1534
Placental growth hormone is the product of the GH-V gene specifically expressed in the syncytiotrophoblast layer of the human placenta. Placental growth hormone differs from pituitary growth hormone by 13 amino acids. It has high somatogenic and low lactogenic activities. Assays by specific monoclonal antibodies reveal that in the maternal circulation from 15 to 20 weeks up to term placental growth hormone gradually replaces pituitary growth hormone, which becomes undetectable. It is secreted by the placenta in a nonpulsatile manner. This continuous secretion appears to have important implications for physiologic adjustment to gestation and especially in the control of maternal insulin-like growth factor-I levels. Placental growth hormone secretion is inhibited by glucose in vitro and in vivo and is significantly decreased in the maternal circulation in pregnancies with intrauterine growth restriction. Placental growth hormone does not appear to have a direct effect on fetal growth because this hormone is not detectable in the fetal circulation. However, the physiologic role might also include a direct influence on placental development through an autocrine or paracrine mechanism, as suggested by the presence of specific growth hormone receptors in this tissue.(Am J Obstet Gynecol 1997;177:1526-34.) 相似文献
953.
Victor Y. Fujimoto MD J.Heath Miller MD Nancy A. Klein MD Michael R. Soules MD 《American journal of obstetrics and gynecology》1997,177(6):1419-1425
OBJECTIVE: Our aim was to evaluate the clinical course and management of congenital cervical atresia. STUDY DESIGN: This retrospective analysis included 7 patients referred to our clinic and a review of the medical literature. RESULTS: Including this case series, 58 cases of congenital cervical atresia have been reported in the literature. Forty-eight percent of patients had isolated congenital cervical atresia with a normal vagina whereas the remainder had either complete or partial vaginal atresia (“shortened blind vaginal pouches”). Surgical management has included abdominal hysterectomy or uterovaginal cannulation with or without vaginoplasty. In 59% of patients who underwent uterovaginal canalization procedures (23/39), normal menstrual bleeding was achieved. Four of these patients subsequently became pregnant and were delivered at term. CONCLUSION: Surgical canalization in selected patients with congenital cervical atresia can be successfully performed to provide patients an opportunity for conservative management, resulting in normal menstrual bleeding, resolution of cyclic pelvic pain, and some potential (albeit limited) for fertility.(Am J Obstet Gynecol 1997;177:25) 相似文献
954.
955.
956.
957.
958.
959.
960.