全文获取类型
收费全文 | 62608篇 |
免费 | 4876篇 |
国内免费 | 3297篇 |
专业分类
耳鼻咽喉 | 772篇 |
儿科学 | 2828篇 |
妇产科学 | 2046篇 |
基础医学 | 8140篇 |
口腔科学 | 2151篇 |
临床医学 | 4507篇 |
内科学 | 7868篇 |
皮肤病学 | 921篇 |
神经病学 | 3751篇 |
特种医学 | 1863篇 |
外国民族医学 | 30篇 |
外科学 | 7351篇 |
综合类 | 9901篇 |
现状与发展 | 15篇 |
预防医学 | 2992篇 |
眼科学 | 2380篇 |
药学 | 5136篇 |
16篇 | |
中国医学 | 1870篇 |
肿瘤学 | 6243篇 |
出版年
2024年 | 133篇 |
2023年 | 639篇 |
2022年 | 1380篇 |
2021年 | 1822篇 |
2020年 | 1631篇 |
2019年 | 1571篇 |
2018年 | 1593篇 |
2017年 | 1911篇 |
2016年 | 1925篇 |
2015年 | 2096篇 |
2014年 | 3623篇 |
2013年 | 4549篇 |
2012年 | 3578篇 |
2011年 | 4211篇 |
2010年 | 3614篇 |
2009年 | 3510篇 |
2008年 | 3619篇 |
2007年 | 3830篇 |
2006年 | 3423篇 |
2005年 | 3123篇 |
2004年 | 2640篇 |
2003年 | 2265篇 |
2002年 | 1902篇 |
2001年 | 1631篇 |
2000年 | 1417篇 |
1999年 | 1146篇 |
1998年 | 980篇 |
1997年 | 868篇 |
1996年 | 798篇 |
1995年 | 657篇 |
1994年 | 590篇 |
1993年 | 507篇 |
1992年 | 443篇 |
1991年 | 381篇 |
1990年 | 357篇 |
1989年 | 295篇 |
1988年 | 219篇 |
1987年 | 205篇 |
1986年 | 190篇 |
1985年 | 264篇 |
1984年 | 208篇 |
1983年 | 149篇 |
1982年 | 200篇 |
1981年 | 143篇 |
1980年 | 109篇 |
1979年 | 80篇 |
1978年 | 80篇 |
1977年 | 63篇 |
1976年 | 59篇 |
1973年 | 39篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
目的观察肠外营养与生长激素联合应用对大手术术后患者蛋白代谢的影响。方法将拟实施外科大手术(四类以上手术)熏APACHE-Ⅱ评分>7分的患者30例,入院后随机分为3组熏A组穴n=10雪押肠外营养治疗与生长激素穴金磊赛增雪联合治疗组(PN+GH)鸦B组穴n=10雪押肠外营养治疗组(PN)鸦C组穴n=10雪押正常补液组。其中A组在术后第2天开始给予生长激素皮下肌注,连续7d。结果术后8d内,B、C组患者均处于负氮平衡状态,血清白蛋白与胰岛素样生长因子-Ⅰ(IGF-Ⅰ)维持较低水平,A组在术后5d机体开始恢复氮平衡,血清白蛋白与IGF-Ⅰ水平逐渐上升,A组与B、C组比较差异有显著性(P<0.05)。结论较大的外科手术打击后,单纯给予常规的肠外营养要素不能被机体有效的利用,GH能够提高机体对肠外营养要素的利用率,促进机体蛋白合成。 相似文献
72.
神经活素对Pc12细胞作用的初步观察 总被引:1,自引:0,他引:1
从胎脑、颌下腺、肌肉组织中制备神经活素。其性能同脑活素一样:可促进Pc12细胞的突起生长,提高其胞浆内乳酸脱氢酶活性,电泳显示二者有相同的三条带。提示:神经活素有可能替代脑活素应用于临床。 相似文献
73.
74.
ABSTRACT. This study shows that children with late-diagnosed congenital dislocation of the hip (CDH) have close to normal height development during the initial 6.0 years of life. The treatment consisted of immobilization for 0.5 to 1.3 years starting between 0.2 and 0.7 years of age. The present work addresses one specific issue that is related to the age at onset of the childhood component of the ICP growth model. The onset normally appears between 0.5 and 1.0 year of age, and is recognized as an increase in length/height velocity. The onset is thus found during a period of increasing motor activity. The normal successive change from sitting to walking position may have some influence on the onset of this tempo change in early linear growth. The present documentation implies that there is no such influence. In all 14 children with CDH, the onset manifested during the period of immobilization, and the average age at onset was found to be Virtually equivalent with that of the controls. Our conclusion is that immobilization has no significant influence on the age at onset of the childhood phase of growth. The onset is accomplished independent of body position, be it lying down or normal for the age. 相似文献
75.
C. Gupta 《Urological research》1997,25(4):277-281
Previous studies from this laboratory indicated a role for epidermal growth factor (EGF) in androgen-dependent male reproductive tract differentiation of the fetal mouse. Expression of an EGF-like protein during Wolffian duct differentiation was indicated from the determinations by radioimmunoassay (RIA) and radioreceptor assay. To further characterize the protein and to assess its role in male sexual differentiation, expression of the protein has been analyzed by Western blot assay and its tissue-specific cellular expression has been determined by immunocytochemical assay in the present study. Western blot analysis of the 18-day fetal male reproductive tract detected an immunoreactive band of the predicted 6-kDa size. Immunocytochemical analysis also detected EGF-specific immunostaining in the Wolffian duct derivatives. At day 18 of gestation, the staining was localized predominantly in the epithelial nuclei of the Wolffian duct derivatives whereas at days 14 and 16 of gestation, the staining was equally distributed in the mesenchymal and epithelial sites of the Wolffian duct derivative. The intensity of the staining increased with progression of differentiation during the 14th–18th days of gestation. Prenatal exposure to the antiandrogen flutamide significantly reduced the immunostaining of the duct. Thus, a role for EGF in Wolffian duct differentiation is indicated. 相似文献
76.
Background: The occurrence of benign bone cysts adjacent to an active physis may be associated with a physeal arrest. That arrest may result from physeal penetration of the cysts itself, secondary pathologic fracture or the result of surgical curettage. Methods : The pre-treatment X-rays of patients attending the Bone Tumor Clinic at the Children's Hospital and Medical Center were reviewed. Those patients presenting with a bone cyst were identified and the affected side was compared to the normal side in order to determine growth discrepancies. Results: Three cases of benign bone cysts are presented that were located adjacent to a growing physis and produced growth disturbance in the absence of surgical intervention. Conclusions: The risk of growth disturbance in itself should not be a contraindication to surgical intervention. 相似文献
77.
Terry Reed 《Clinical genetics》1991,39(5):391-395
Evidence from the literature is reviewed to suggest that when fingertip dermal ridge patterns in chromosomal deletion syndromes are characteristic of the opposite spectrum of the developmental scale from patterns found in cases trisomic for the same chromosomal region, the association may be a consequence of loci with growth regulatory functions. Evidence is presented that DNA markers at 18q21 should be the first candidate sequences to be used to test this hypothesis in families with fingertip arches segregating in an apparent autosomal dominant fashion. 相似文献
78.
79.
“软骨康”对损伤关节软骨修复机制的初探 总被引:3,自引:0,他引:3
我们用中药软骨康,对全层缺损的兔膝关节股骨髁关节软骨,进行三周治疗,取得较为满意的效果。实验结果表明,软骨康在促进成纤维细胞分泌大量胶原纤维,促进组织再生;对血管增生和扩张血管加速局部血循环以及提高滑膜的增生和活性,使其参与损伤组织的再建,均有独到作用。 相似文献
80.
C McKenzie BAppSc P Megaw BAppSc I Morgan PhD MK Boelen PhD 《Clinical & experimental ophthalmology》1997,25(4):79-81
Deprivation of form vision by the fitting of translucent occluders suppressed the diurnal cycling of enkephalinergic amacrine cells (the ENSLI amacrine cells), in the chicken. Daily periods of normal vision or enforcing temporal contrast using strobe lighting appeared to restore normal functioning of the ENSLI cells. These results suggest that the ENSLI cells are involved in retinal circuits that assess the quality of the visual image and control eye growth. 相似文献