全文获取类型
收费全文 | 1829篇 |
免费 | 0篇 |
专业分类
化学工业 | 9篇 |
机械仪表 | 6篇 |
建筑科学 | 7篇 |
能源动力 | 1篇 |
轻工业 | 5篇 |
石油天然气 | 17篇 |
无线电 | 1篇 |
一般工业技术 | 2篇 |
冶金工业 | 1755篇 |
自动化技术 | 26篇 |
出版年
2022年 | 1篇 |
2020年 | 1篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2015年 | 1篇 |
2014年 | 7篇 |
2013年 | 4篇 |
2012年 | 3篇 |
2011年 | 1篇 |
2010年 | 5篇 |
2009年 | 5篇 |
2008年 | 1篇 |
2007年 | 3篇 |
2006年 | 1篇 |
2005年 | 5篇 |
2004年 | 2篇 |
2003年 | 16篇 |
2002年 | 6篇 |
2001年 | 9篇 |
2000年 | 3篇 |
1999年 | 54篇 |
1998年 | 525篇 |
1997年 | 292篇 |
1996年 | 228篇 |
1995年 | 110篇 |
1994年 | 98篇 |
1993年 | 105篇 |
1992年 | 11篇 |
1991年 | 30篇 |
1990年 | 32篇 |
1989年 | 23篇 |
1988年 | 37篇 |
1987年 | 22篇 |
1986年 | 22篇 |
1985年 | 13篇 |
1983年 | 3篇 |
1982年 | 10篇 |
1981年 | 12篇 |
1980年 | 11篇 |
1978年 | 3篇 |
1977年 | 38篇 |
1976年 | 72篇 |
1966年 | 1篇 |
排序方式: 共有1829条查询结果,搜索用时 0 毫秒
31.
32.
33.
In this article, we review the criteria used to establish a causal association. A literature search strategy will be outlined. We present a clinical scenario that was formulated to examine the evidence for nonsteroidal anti-inflammatory drugs as a possible cause of gastrointestinal ulceration and bleeding. Several of the studies identified in the literature search were critically appraised and the criteria needed to confirm a causal link were then applied. These guidelines may be employed to not only demonstrate the aetiology of a disease but have wider applicability in terms of determining whether a medication may be causing certain adverse events. 相似文献
34.
A 6-week-old breast-fed infant had obstructive jaundice and hepatomegaly. When a dry-cleaning solvent, tetrachloroethylene, was detected in the mother's milk and blood, breast-feeding was discontinued. Rapid clinical and biochemical improvement followed. The child grew normally and had normal liver function during 2 years of follow-up. 相似文献
35.
HF Chambers T Kocag?z T Sipit J Turner PC Hopewell 《Canadian Metallurgical Quarterly》1998,26(4):874-877
Some beta-lactam antibiotics are active in vitro against Mycobacterium tuberculosis. There are anecdotal reports of successful treatment of tuberculosis caused by multiple-drug-resistant strains of M. tuberculosis with regimens that included amoxicillin/clavulanate. Reduction of M. tuberculosis in the sputum of patients with pulmonary tuberculosis during administration of amoxicillin/clavulanate was measured by a quantitative culture method to determine the activity in vivo. Patients were randomized to receive isoniazid, ofloxacin, or amoxicillin/clavulanate for 7 days. Isoniazid was the most effective agent, reducing M. tuberculosis after 2 days at a mean rate (+/- standard deviation) of 0.60 +/- 0.30 log10 cfu/mL per day, compared with 0.32 +/- 0.05 and 0.34 +/- 0.03 for ofloxacin and amoxicillin/clavulanate, respectively. The early bactericidal activity of amoxicillin/clavulanate was comparable to that reported for antituberculous agents other than isoniazid. Further studies of beta-lactam antibiotics with in vitro activity against M. tuberculosis are warranted to define their role in treatment of tuberculosis. 相似文献
36.
Asplenia syndrome in conjoined twins: a case report 总被引:1,自引:0,他引:1
Incomplete fission of the primordial cell mass is generally believed to be the cause of conjoined twinning. It may also explain the tendency towards increased symmetry in these twins. We report a case of the rostral duplication type of conjoined twins with an absence of symmetry; one twin had the asplenia syndrome, whereas the other twin was normal. Local environmental factors acting upon the organ anlage may explain the asymmetric development in these conjoined twins. 相似文献
37.
38.
正随着IT技术的不断进步,智能手机的更新换代也正在逐渐加快,但替换下来的旧手机仍旧有很强的性能,如果就此放置一旁无疑是一种极大的浪费。除了将手机作为二手产品低价出售,还有什么办法能够让手机物尽其用呢?Android手机如今已经成为人们生活、工作必备的设备。相信如果你某天找不到手机,那么你一天的生活节奏一定会被弄的混乱不堪。随着IT技术的不断进步,智能手机的更新换代也正在逐渐加快,但替换下来的旧手机仍旧有很强的性能,如果就此放置一旁无疑是一种极大的浪费。 相似文献
39.
上网本
我办公室有办公用笔记本电脑,家里有台式PC,而华硕Eee PC 1000HE算是我的随身电脑。 相似文献
40.