全文获取类型
收费全文 | 188192篇 |
免费 | 34585篇 |
国内免费 | 2613篇 |
专业分类
耳鼻咽喉 | 5601篇 |
儿科学 | 6601篇 |
妇产科学 | 3451篇 |
基础医学 | 7141篇 |
口腔科学 | 2830篇 |
临床医学 | 29836篇 |
内科学 | 55469篇 |
皮肤病学 | 8103篇 |
神经病学 | 16931篇 |
特种医学 | 7673篇 |
外国民族医学 | 8篇 |
外科学 | 47851篇 |
综合类 | 1265篇 |
现状与发展 | 75篇 |
一般理论 | 29篇 |
预防医学 | 9743篇 |
眼科学 | 4720篇 |
药学 | 4144篇 |
1篇 | |
中国医学 | 339篇 |
肿瘤学 | 13579篇 |
出版年
2024年 | 541篇 |
2023年 | 5115篇 |
2022年 | 2084篇 |
2021年 | 4913篇 |
2020年 | 7026篇 |
2019年 | 3539篇 |
2018年 | 8989篇 |
2017年 | 8486篇 |
2016年 | 9693篇 |
2015年 | 9804篇 |
2014年 | 17235篇 |
2013年 | 17764篇 |
2012年 | 8783篇 |
2011年 | 8724篇 |
2010年 | 12098篇 |
2009年 | 15688篇 |
2008年 | 8141篇 |
2007年 | 6382篇 |
2006年 | 8577篇 |
2005年 | 5635篇 |
2004年 | 4712篇 |
2003年 | 3387篇 |
2002年 | 3310篇 |
2001年 | 4151篇 |
2000年 | 3314篇 |
1999年 | 3497篇 |
1998年 | 3845篇 |
1997年 | 3592篇 |
1996年 | 3506篇 |
1995年 | 3323篇 |
1994年 | 2051篇 |
1993年 | 1650篇 |
1992年 | 1526篇 |
1991年 | 1564篇 |
1990年 | 1191篇 |
1989年 | 1315篇 |
1988年 | 1129篇 |
1987年 | 970篇 |
1986年 | 980篇 |
1985年 | 835篇 |
1984年 | 627篇 |
1983年 | 583篇 |
1982年 | 578篇 |
1981年 | 468篇 |
1980年 | 408篇 |
1979年 | 359篇 |
1978年 | 371篇 |
1977年 | 438篇 |
1975年 | 317篇 |
1972年 | 326篇 |
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
991.
Joseph D. obias MD Sandra Lowe MD George W. Holcomb III MD 《Journal of clinical anesthesia》1992,4(6):484-486
The case of a 3-day-old infant with Beckwith-Wiedemann syndrome who required anesthetic care during closure of an abdominal wall defect is presented. Beckwith-Wiedemann syndrome comprises a constellation of clinical features, including macroglossia, macrosomia, omphalocele, visceromegaly, mild microcephaly, facial nevus flammeus, horizontal earlobe creases, and renal medullary dysplasia. Due to the high rate of omphalocele in this syndrome, anesthetic care is frequently required during the neonatal period. Many of these infants (greater than 50%) are born prematurely. Therefore, their anesthetic care may be further complicated by associated diseases of prematurity, such as hyaline membrane disease. Additional anesthetic implications of this syndrome relate to the occurrence and management of hypoglycemia and polycythemia. Careful intraoperative management of glucose homeostasis is particularly important, since eventual neurologic outcome and intelligence will be normal provided prolonged neonatal hypoglycemia is avoided. Preoperative evaluation of the cardiac and genitourinary system, including echocardiography and renal ultrasound, are recommended because of the frequent occurrence of associated anomalies with omphalocele. 相似文献
992.
Metastatic tumors to the oral cavity are uncommon. Most of these cases involve the mandible or the maxilla. Rarely, metastasis occurs to the oral soft tissues from a distant primary tumor. The lung and breast are the most common primary sites. It is extremely rare to have an oral soft-tissue metastasis from a carcinoma of the colon. A case of primary adenocarcinoma of the colon with metastasis to the soft tissues of the mouth is described. Three similar case reports are reviewed. A metastatic lesion to the oral cavity could be the first indication of the presence of a primary tumor. 相似文献
993.
M. M. Ali S. Jayabalan M. Machnicki G. S. Sohal 《International journal of developmental neuroscience》2003,21(4):199-208
Virtually all cell types in the inner ear develop from the cells of the otic vesicle. The otic vesicle is formed by the invagination of non-neural ectodermal cells known as the otic placode. We investigated whether a recently described cell population, originating from the ventral part of the hindbrain neural tube known as the ventrally emigrating neural tube (VENT) cells, also contributes cells to the otic vesicle. The ventral hindbrain neural tube cells were labeled with the fluorescent vital dye DiI or replication-deficient retroviruses containing the LacZ gene in chick embryos on embryonic day 2, after the emigration of neural crest from this region. One day later, the labeled cells were detected only in the hindbrain neural tube. Shortly thereafter, the labeled cells began to appear in the eighth (vestibulocochlear) cranial nerve and otic vesicle. From embryonic day 3.5-5, the labeled cells were detected in the major derivatives of the otic vesicle, i.e. the endolymphatic duct, semicircular canals, utricle, saccule, cochlea, and vestibulocochlear ganglion. That the emigrated cells originated from the ventral part of the hindbrain neural tube was confirmed by focal application of DiI impregnated filter paper and with quail chimeras. It is concluded that, in addition to the otic placode cells, the otic vesicle also contains the ventrally emigrating neural tube cells, and that both cell populations contribute to the structures and cell types in the inner ear. It is well known that inductive signals from the hindbrain are required for the morphogenesis of the inner ear. The migration of the hindbrain neural tube cells into the otic vesicle raises the possibility that the inductive effect of the hindbrain might be mediated, at least in part, by the ventrally emigrating neural tube cells and that, therefore, a mechanism exists that involves cells rather than diffusible molecules only. 相似文献
994.
995.
996.
997.
998.
Jens Toft Birger Hesse Alan Rabøl Steen Carstensen Samir Ali 《European journal of nuclear medicine and molecular imaging》1997,24(4):409-414
Reference data files support the evaluation of myocardial perfusion single-photon emission tomography (SPET). The aim of this study was to create a large reference data base for technetium-99m sestamibi SPET, age and gender matched to the general patient population. One hundred and twenty-eight healthy volunteers (76 males and 52 females) with a likelihood of coronary artery disease of less than 5% underwent rest and maximal exercise99mTc-sestamibi SPET with a 2-day protocol and 180° elliptical rotation. The normalized activity values of99mTc-sestamibi in the inferior wall differed significantly between men and women. Age variations were found for men in the anterior wall. Normalized activity values in all four walls were strikingly similar during rest and stress. Our results suggest that the use of reference files in99mTc-sestamibi SPET requires a gender- and, for males, possibly an age-matched reference population. Different reference files at rest and during stress might not be necessary. 相似文献
999.
MD MPHCecilia Albala MD MScMabel Y ez MPh Mat.Sc.Gabriela Salazar MD MPHFernando Vio 《Nutrition Research》1994,14(12):1797-1809
Body composition measured with isotopic dilution was compared with anthropometric measurements. The study was carried out in 47 subjects from both sexes, 65 to 92 years old. Total body water (TBW), anthropometric measurements, and dynamometry were assessed. TBW was significatively higher in men than women and decreased with age. Dynamometry and fatfree mass were well correlated (r=0.73 in males and r=0.58 in females) and significantly different between sexes. A negative correlation was found for dynamometry with age, being significant for women. Linear regression equations to predict TBW from anthropometric measurements in males and females were obtained: Males: TBW(I)=19.349+0.617 weight(kg) — 0.931 mid-arm circumference(cm)+0.122 dynamometry (kg) Females: TBW(l)=−5.531+0.343 weight(kg)-0.213 triceps skinfold (mm)+ 0.148 dynamometry(kg) + 3.424 wrist diameter (cm). This simple model is proposed for use in epidemiological and field studies where other more sophisticated methods can not be applied. 相似文献
1000.
Palmar advancement flap with V-Y closure for thumb tip injuries 总被引:1,自引:0,他引:1
Hwang-hyun Bang MD Tadao Kojima MD Hiroyuki Hayashi MD 《The Journal of hand surgery》1992,17(5):933-934
The palmar advancement flap with V-Y closure was used in two patients with thumb tip injuries. This technique allows more distal advancement of the flap than does a conventional palmar advancement flap and does not require skin graft coverage. 相似文献