全文获取类型
收费全文 | 1445篇 |
免费 | 83篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 111篇 |
妇产科学 | 31篇 |
基础医学 | 125篇 |
口腔科学 | 118篇 |
临床医学 | 130篇 |
内科学 | 280篇 |
皮肤病学 | 20篇 |
神经病学 | 94篇 |
特种医学 | 243篇 |
外国民族医学 | 1篇 |
外科学 | 123篇 |
综合类 | 34篇 |
一般理论 | 2篇 |
预防医学 | 75篇 |
眼科学 | 6篇 |
药学 | 57篇 |
中国医学 | 6篇 |
肿瘤学 | 79篇 |
出版年
2023年 | 11篇 |
2022年 | 11篇 |
2021年 | 26篇 |
2020年 | 17篇 |
2019年 | 18篇 |
2018年 | 20篇 |
2017年 | 21篇 |
2016年 | 28篇 |
2015年 | 26篇 |
2014年 | 28篇 |
2013年 | 39篇 |
2012年 | 57篇 |
2011年 | 49篇 |
2010年 | 35篇 |
2009年 | 45篇 |
2008年 | 37篇 |
2007年 | 46篇 |
2006年 | 51篇 |
2005年 | 42篇 |
2004年 | 33篇 |
2003年 | 38篇 |
2002年 | 29篇 |
2001年 | 42篇 |
2000年 | 32篇 |
1999年 | 24篇 |
1998年 | 54篇 |
1997年 | 51篇 |
1996年 | 42篇 |
1995年 | 27篇 |
1994年 | 45篇 |
1993年 | 27篇 |
1992年 | 19篇 |
1991年 | 26篇 |
1990年 | 16篇 |
1989年 | 42篇 |
1988年 | 36篇 |
1987年 | 30篇 |
1986年 | 44篇 |
1985年 | 39篇 |
1984年 | 28篇 |
1983年 | 26篇 |
1982年 | 17篇 |
1981年 | 31篇 |
1980年 | 12篇 |
1979年 | 14篇 |
1978年 | 12篇 |
1977年 | 15篇 |
1976年 | 13篇 |
1975年 | 12篇 |
1967年 | 8篇 |
排序方式: 共有1545条查询结果,搜索用时 0 毫秒
1.
2.
3.
S. Salardl L. F. Orsini E. Cacciari F. Righetti S. Donati M. Mandini A. Cicognani L. Bovlcelli 《Clinical endocrinology》1991,34(3):187-190
Serum growth hormone (GH), insulin-like growth factor (IGF-I), insulin and C-peptide were measured by RIA in fetal blood collected in utero by umbilical cord puncture performed for a variety of indications. Eighty-four fetuses were aged 19-25 weeks and 14 were 26-37 weeks. IGF-I values were lower than the sensitivity of the method. The range for GH was 3-197 micrograms/l (GH-micrograms/l x 2 = mU/l), for insulin 14.3-117 pmol/l, for C-peptide 66.2-827.5 pmol/l. GH significantly increased from week 19 to 25; insulin and C-peptide levels increased from week 19 to 37. GH levels at 19-25 weeks were significantly higher in fetuses with femoral length less than the 5th compared with those with femoral length greater than the 95th centile for that age. GH and insulin levels did not correlate with weight at birth or with maternal hormone levels. These data provide evidence for a presence in living fetuses, from the 19th week, of high levels of GH and of insulin levels not very different from those in adults but these hormones do not seem to be directly responsible for fetal growth. 相似文献
4.
Brain histamine levels were determined in golden hamster hypothalamus and 'brain minus hypothalamus' on each of the 4 days of the estrous cycle and on selected days of pregnancy. The highest histamine content of the hypothalamus was observed on day 3 of the estrous cycle. The highest histamine content of the hypothalamus was observed on day 3 of the estrous cycle, which is the day prior to recurrence of heat on day 4. Day 4 terminates in ovulation. The histamine level in the remainder of the brain peaked on day 2. During gestation the histamine content of the 'brain minus hypothalamus' was greatest on day 5, while the maximum content of histamine in the hypothalamus was not reached until day 8. After the 8th day of pregnancy, there was an overall decline in brain histamine that continued until parturition. The hypothalamic histamine level in nonpregnant females was not different from that of males. However, in the remainder of the brain, histamine levels in females on days 1 and 2 of the estrous cycle were higher than in males. 相似文献
5.
6.
7.
F. Sartucci G. Orlandi U. Bonuccelli D. Borghetti L. Murri C. Orsini L. Domenici V. Porciatti 《Neurological sciences》2006,26(6):395-401
Abstract Idiopathic Parkinson’s disease (IPD) patients have abnormal visual evoked potentials (VEPs) and pattern electroretinograms
(PERGs), attributed to dopaminergic transmission deficiency in visual pathway, probably the retina. VEP abnormalities are
not reported in multiple system atrophy (MSA). The aim of this study was to investigate and compare chromatic (Ch) red-green
(R-G) and blue-yellow (B-Y), and luminance yellow-black (Y-Bk) PERGs in patients with MSA and IPD. We investigated 6 MSA patients
(mean age: 62±7.4 years) not undergoing any pharmacological treatment, as well as 12 early IPD patients (mean age: 60.1±8.3
years) and 12 age-matched normal observers. ChPERGs were recorded monocularly in response to full-field equiluminant R-G,
B-Y and Y-Bk horizontal gratings. In MSA only responses to R-G stimuli showed minimal insignificant changes (slight but not
significant amplitude reduction without any significant latency delay); no significant abnormality was detected for B-Y and
luminance Y-Bk stimuli. By contrast, in IPD all responses were reduced in amplitude and delayed in latency, above all for
B-Y stimuli. Present data indicate that both chromatic and achromatic PERGs are virtually unaffected in MSA, whereas in early
IPD they are clearly impaired, suggesting different pathogenic retinal mechanisms and a useful simple tool for distinguishing
MSA from IPD. 相似文献
8.
9.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
10.