首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2031篇
  免费   0篇
电工技术   2篇
化学工业   11篇
机械仪表   2篇
建筑科学   4篇
能源动力   1篇
轻工业   7篇
无线电   33篇
一般工业技术   4篇
冶金工业   1963篇
自动化技术   4篇
  2022年   1篇
  2017年   1篇
  2013年   7篇
  2012年   3篇
  2011年   1篇
  2009年   1篇
  2008年   3篇
  2007年   4篇
  2006年   4篇
  2004年   2篇
  2003年   4篇
  2002年   2篇
  2001年   1篇
  2000年   3篇
  1999年   70篇
  1998年   587篇
  1997年   314篇
  1996年   193篇
  1995年   107篇
  1994年   118篇
  1993年   120篇
  1992年   8篇
  1991年   19篇
  1990年   23篇
  1989年   28篇
  1988年   28篇
  1987年   22篇
  1986年   24篇
  1985年   23篇
  1984年   2篇
  1983年   6篇
  1982年   12篇
  1981年   20篇
  1980年   21篇
  1979年   6篇
  1978年   3篇
  1977年   68篇
  1976年   163篇
  1975年   3篇
  1973年   1篇
  1966年   1篇
  1965年   2篇
  1964年   1篇
  1954年   1篇
排序方式: 共有2031条查询结果,搜索用时 15 毫秒
81.
Presents the authors' views of the debate on false memory syndrome in light of the article by K. S. Pope (see record 83-37387). The authors highlight the need to move the debate from the political realm to the scientific realm, and to apply the standards of scientific inquiry and integrity to all claims made by those who would have their message conveyed with the validating stamp of "science," including the False Memory Syndrome Foundation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
The continued success of renal transplantation has provided a higher quality of life for properly selected patients with ESRD. It is also a much more cost-effective and efficient treatment of ESRD compared with chronic dialysis. Innovative urologic reconstructive surgery using enteric segments for both continent and incontinent urinary diversions has permitted this therapeutic modality to be offered to the recipient with lower urinary tract disease not previously amenable to renal transplantation. These same reconstructive techniques using ileal segments have also permitted preservation of renal allografts with previously nonreconstructable renal pelvic or ureteral disease.  相似文献   
83.
84.
85.
Probability theory is applied to the analysis of fMRI data. The posterior distribution of the parameters is shown to incorporate all the information available from the data, the hypotheses, and the prior information. Under appropriate simplifying conditions, the theory reduces to the standard statistical test, including the general linear model. The theory is particularly suited to handle the spatial variations in the noise present in fMRI, allowing the comparison of activated voxels that have different, and unknown, noise. The theory also explicitly includes prior information, which is shown to be critical in the attainment of reliable activation maps.  相似文献   
86.
This research was carried out to analyse the visits specialists of the Dutch Animal Health Service made to growing and fattening pig farms. The type and frequency of the visits and identified herd-health management factors that did not meet accepted standards were investigated. In total 373 visit reports were studied. The majority of the visits (n = 306 of 373) were made to investigate the cause of health, welfare, and performance problems ('problem-solving visits'). Respiratory disorders were the main reason for requesting a specialist to assess farm conditions and management (n = 156). In the other 67 of 373 visit reports the specialists screened for herd-health management factors that did not meet standards for the prevention of disease ('screening visits'). For both types of visits, the main factors detected were abrupt changes in feeding regimens (e.g. changes in feed type, feed composition or feed supplier) (37%), inadequate measures to prevent introduction of pathogens by people and trucks (83%), and incorrect adjustment of the ventilation system (58-60%). The specialists focusing on housing-climate management, identified the majority of factors in an equal number irrespective of whether the visit was a problem-solving visit or a screening visit. This implies that even on farms that appear not to have health or performance problems, factors that relate to disease are present and may cause problems sooner or later. Although veterinary practitioners and other farm advisors assist farmers in their management to optimize herd health, the findings of the research suggest that advisors could provide additional support in situations where environmental and managerial factors play a role in pig health and performance. The knowledge of advisors about integrated herd-health management can be broadened by means of textbooks, courses, or computer programs.  相似文献   
87.
We have determined that three type-specific and conformationally dependent monoclonal antibodies, H16.E70, H16.U4, and H16.V5, neutralize pseudotype human papillomavirus type 16 (HPV16) virions in vitro. H16.U4 and H16.V5 neutralized pseudotype virions derived from the German HPV16 variant 114K and the Zairian variant Z-1194 with equal efficiency. In contrast, neutralization of Z-1194 pseudotype virions by H16.E70 was two orders of magnitude weaker than neutralization of 114K pseudotype virions. This difference correlated with enzyme-linked immunosorbent assay reactivity of H16.E70 to L1 virus-like particles of the two variants. A substitution at residue 282 of L1 was responsible for this differential reactivity, suggesting that this residue constitutes part of the H16.E70 epitope.  相似文献   
88.
In a randomized open study, 351 male patients with uncomplicated gonorrhea were given single oral doses of grepafloxacin (400 mg) or cefixime (400 mg). In the 299 microbiologically evaluable patients, urethral infections were cured in 99% (147 of 149) of those receiving grepafloxacin and 97% (145 of 150) of those given cefixime. Eradication rates for both regimens were 100% in the 16% (47 of 299) of participants who were infected with penicillin-resistant Neisseria gonorrhoeae and 97% in the 21% (62 of 299) of participants infected with tetracycline-resistant strains. Grepafloxacin is a well-tolerated alternative to cefixime for treatment of uncomplicated gonorrhea in males.  相似文献   
89.
The contraceptive steroid ethinyl estradiol was extensively metabolized when given orally in solution to dogs. It was thought at first that metabolism occurred exclusively in the liver. However, use of standard equations to predict the oral bioavailability of drugs known to be metabolized by hepatic first pass resulted in significantly higher values than those obtained experimentally. To rationalize the data and to determine whether ethinyl estradiol also is metabolized in the gut wall during absorption, metabolism in rats was studied. The drug was administered in solution intraduodenally, intraportally, and intravenously as a bolus by first-order infusion. The results indicate that, in rats, 40% of the drug is metabolized by the gut wall and 79% of the drug in the portal blood is metabolized by the liver intraduodenal administration.  相似文献   
90.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号