全文获取类型
收费全文 | 298183篇 |
免费 | 17293篇 |
国内免费 | 434篇 |
专业分类
耳鼻咽喉 | 4304篇 |
儿科学 | 10409篇 |
妇产科学 | 10323篇 |
基础医学 | 45066篇 |
口腔科学 | 7548篇 |
临床医学 | 24282篇 |
内科学 | 56221篇 |
皮肤病学 | 6337篇 |
神经病学 | 21191篇 |
特种医学 | 11676篇 |
外国民族医学 | 43篇 |
外科学 | 47200篇 |
综合类 | 7790篇 |
现状与发展 | 1篇 |
一般理论 | 160篇 |
预防医学 | 19919篇 |
眼科学 | 7006篇 |
药学 | 20935篇 |
中国医学 | 788篇 |
肿瘤学 | 14711篇 |
出版年
2019年 | 2286篇 |
2018年 | 3655篇 |
2017年 | 2676篇 |
2016年 | 3144篇 |
2015年 | 3559篇 |
2014年 | 4651篇 |
2013年 | 7293篇 |
2012年 | 9188篇 |
2011年 | 9557篇 |
2010年 | 6212篇 |
2009年 | 5617篇 |
2008年 | 8821篇 |
2007年 | 9700篇 |
2006年 | 9526篇 |
2005年 | 9128篇 |
2004年 | 8814篇 |
2003年 | 8295篇 |
2002年 | 7875篇 |
2001年 | 13347篇 |
2000年 | 13666篇 |
1999年 | 11429篇 |
1998年 | 3038篇 |
1997年 | 2797篇 |
1996年 | 2640篇 |
1995年 | 2550篇 |
1994年 | 2345篇 |
1992年 | 8313篇 |
1991年 | 8452篇 |
1990年 | 8264篇 |
1989年 | 8077篇 |
1988年 | 7315篇 |
1987年 | 7071篇 |
1986年 | 6719篇 |
1985年 | 6514篇 |
1984年 | 4763篇 |
1983年 | 4119篇 |
1982年 | 2469篇 |
1979年 | 4427篇 |
1978年 | 3229篇 |
1977年 | 2732篇 |
1976年 | 2503篇 |
1975年 | 2833篇 |
1974年 | 3352篇 |
1973年 | 3362篇 |
1972年 | 3118篇 |
1971年 | 2948篇 |
1970年 | 2838篇 |
1969年 | 2581篇 |
1968年 | 2538篇 |
1967年 | 2373篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Is colonic electrical activity a similar phenomena to small-bowel electrical activity? 总被引:4,自引:0,他引:4
Dr. José A. S. Medeiros M.D. Ph.D. Fausto A. Pontes M.D. Ph.D. Octávio A. R. O. Mesquita 《Diseases of the colon and rectum》1997,40(1):93-99
PURPOSE: This study was designed to investigate colonic spike bursts regarding 1) their migration behavior, 2) their pressure correlates, and 3) comparing colonic short spike bursts with spike bursts from migrating myoelectric complex from the small bowel. METHODS: Rectosigmoid electromyography and manometry were recorded simultaneously in seven normal volunteers and electromyography alone in five others during two hours of fasting and for two hours after one 2,100-kJ meal. One patient with an ileostomy was also studied by the same method to record the migrating myoelectric complex from the terminal ileum during fasting. RESULTS: Three kinds of spike bursts were observed in the pelvic colon: rhythmic short spike bursts, migrating long spike bursts, and nonmigrating long spike bursts. The meal significantly increased the number of migrating and nonmigrating long spike bursts (from 25 to 38.7 percent of the recording time;
P
<0.01). These bursts of potentials showed a peak 15 minutes after the meal, which may be caused by the gastrocolic reflex. Migrating long spike bursts started anywhere along the rectosigmoid and migrated from there aborad 82 percent of the time and orad or in both directions in 10 or 7 percent of the time, respectively. They originated pressure waves 99 percent of the time. Short spike bursts were more frequent before the meal (15.1 percent before and 9.6 percent after the meal), but the difference was not significant; they neither propagated nor initiated pressure waves detected by the miniballoon. CONCLUSIONS: Migrating long spike bursts were the only potentials that migrated, sometimes for short distances. Short spike bursts are a different phenomenon from the small-bowel migrating myoelectric complex because they do not migrate; they can occur during the postprandial period and never originated intraluminal pressure waves.Supported by a grant from the Instituto Nacional de Investigação Científica, Proc. DBI-22086.Presented at the meeting of the Portuguese Congress of Gastrenterology, Vila Moura, Portugal, June 2 to 5, 1993. 相似文献
52.
Since 1987, 80 hydroxyapatite-coated (HA) cementless total hip prostheses have been implanted. Thirty patients were examined 21 months postoperatively and the results compared with data for uncoated prosthesis. Earlier mobilization and freedom from pain, together with evidence of bone ingrowth without connective tissue membrane formation, confirmed the benefits of HA-coated prostheses. 相似文献
53.
Summary Intracavitary application of ultrasound was first performed for diagnostic purposes in 1967; since that time, it has been
more and more widely used. As far as the gastrointestinal tract is concerned, endoscopically controlled ultrasonic probes
provide visualization of the various layers of the intestinal wall. It is therefore possible to describe lesions of the esophagus,
stomach, and the rectum with regard to their nature and depth of infiltration. Furthermore, periesophageal and perigastric
organs can be visualized. It has become evident that endosonography is particularly important for pretherapeutic staging of
tumors of the esophagus, stomach, and rectum. Here prospective comparative studies confirm the superiority of this new diagnostic
procedure when compared to the methods available to date. 相似文献
54.
55.
The acting or interim leadership position has been neglected in terms of selection, role identification, and status. Individuals, programs, and organizations are paying a price for this inattention. 相似文献
56.
57.
O Rasmussen E Winther J Arnfred K Hermansen 《European journal of clinical nutrition》1988,42(11):953-961
Recently, we demonstrated that spaghetti caused significantly lower glycaemic response than rice and potato in insulin-dependent diabetic (IDDM) subjects and that this difference was also present when spaghetti and potato were taken as part of a mixed meal. We have now compared the blood glucose and insulin responses to 50 g of carbohydrate in the form of white bread, potato and white spaghetti in 6 non-insulin-dependent diabetic (NIDDM) patients. The blood glucose response after white spaghetti observed over a 3-h period was only 60 +/- 10 per cent (P less than 0.02) of that seen in response to potato (395 +/- 116 mmol/l x 180 min vs 641 +/- 108 mmol/l x 180 min) and 47 +/- 9 per cent (P less than 0.01) of that seen in response to white bread (395 +/- 116 mmol/l x 180 min vs 805 +/- 93 mmol/l x 180 min). Insulin responses showed an identical pattern reflecting the glycaemic responses. To see if the difference in the glucose responses in NIDDM patients is preserved if these carbohydrate-rich foods are taken as part of a mixed meal we looked at the blood glucose and insulin responses to 50 g of carbohydrate in the form of potato and white spaghetti when ingested together with bolognese sauce (167 g) in 7 NIDDM patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
58.
A. Giacometti O. Cirioni G. Greganti A. Fineo R. Ghiselli M. Del Prete F. Mocchegiani B. Fileni F. Caselli E. Petrelli V. Saba G. Scalise 《European journal of clinical microbiology & infectious diseases》2002,21(7):553-556
The in vitro activities of povidone iodine, potassium peroxymonosulfate, and dimethyldidecylammonium chloride were investigated
against 379 nosocomial isolates of Staphylococcus aureus and Pseudomonas aeruginosa responsible for surgical wound infections in patients operated on between July 1995 and June 2001. Overall, the isolates
were inhibited by the antiseptics at concentrations below those used routinely. In spite of increasing resistance to the various
antibiotics used to treat surgical wound infections, no significant variation in the susceptibility to antiseptics was demonstrated
during this 6-year study.
Electronic Publication 相似文献
59.
A. O. Azghani J. W. Baker S. Shetty E. J. Miller G. J. Bhat 《Inflammation research》2002,51(10):506-510
OBJECTIVE AND DESIGN: Bacterial products as well as the host airway inflammatory responses contribute to the pathogenesis of Pseudomonas infections. We sought to determine if Pseudomonas elastase (PE) induces mitogen-activated protein (MAP) kinase activity in association with interleukin-8 (IL-8) production by alveolar epithelial cells. METHODS: We utilized Western blot analysis to detect phosphorylation of signaling intermediates and ELISA was used to measure IL-8 production. RESULTS: We found that PE induces phosphorylation of the extracellular signal-regulated (ERK1/2) proteins of the MAPK pathway in A549 epithelial cells. Similar results were obtained using primary cultures of rabbit alveolar type II epithelial cells. PE also enhanced IL-8 production, which was abolished in the presence of the ERK activation inhibitor U0126. CONCLUSIONS: We conclude that PE activates the ERK1/2 arm of the MAPK pathway and that activation of this pathway results in enhanced IL-8 production. The results demonstrate that PE may augment pulmonary inflammation via cellular signaling that regulates expression of IL-8. 相似文献