全文获取类型
收费全文 | 4373篇 |
免费 | 231篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 63篇 |
儿科学 | 96篇 |
妇产科学 | 106篇 |
基础医学 | 567篇 |
口腔科学 | 94篇 |
临床医学 | 317篇 |
内科学 | 1183篇 |
皮肤病学 | 103篇 |
神经病学 | 374篇 |
特种医学 | 85篇 |
外科学 | 342篇 |
综合类 | 21篇 |
预防医学 | 361篇 |
眼科学 | 117篇 |
药学 | 352篇 |
中国医学 | 30篇 |
肿瘤学 | 427篇 |
出版年
2024年 | 4篇 |
2023年 | 31篇 |
2022年 | 80篇 |
2021年 | 135篇 |
2020年 | 90篇 |
2019年 | 111篇 |
2018年 | 140篇 |
2017年 | 90篇 |
2016年 | 97篇 |
2015年 | 128篇 |
2014年 | 146篇 |
2013年 | 195篇 |
2012年 | 355篇 |
2011年 | 330篇 |
2010年 | 186篇 |
2009年 | 158篇 |
2008年 | 313篇 |
2007年 | 302篇 |
2006年 | 289篇 |
2005年 | 249篇 |
2004年 | 239篇 |
2003年 | 225篇 |
2002年 | 222篇 |
2001年 | 47篇 |
2000年 | 39篇 |
1999年 | 48篇 |
1998年 | 37篇 |
1997年 | 35篇 |
1996年 | 34篇 |
1995年 | 30篇 |
1994年 | 25篇 |
1993年 | 17篇 |
1992年 | 27篇 |
1991年 | 21篇 |
1990年 | 20篇 |
1989年 | 17篇 |
1988年 | 16篇 |
1987年 | 8篇 |
1986年 | 8篇 |
1985年 | 14篇 |
1984年 | 7篇 |
1983年 | 6篇 |
1982年 | 6篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 5篇 |
1978年 | 7篇 |
1977年 | 4篇 |
1976年 | 4篇 |
1975年 | 4篇 |
排序方式: 共有4638条查询结果,搜索用时 15 毫秒
61.
62.
Background. Studies have suggested that scans with technetium-tagged white blood cells (WBC-Tc99m) may be equal to endoscopy in the assessment of extent and activity of inflammatory bowel disease (IBD). Objective. We have retrospectively examined the accuracy of WBC-Tc99m scans in differentiating continuous from discontinuous colitis in pediatric IBD. Materials and methods. There were 207 children in the study (96 boys, 111 girls, median age 13 years). This included 29 controls – children with
no gastrointestinal disease (NL) who underwent WBC-Tc99m scans for other medical problems. Scans were obtained at 30 minutes and 2–4 hours following injection. Scans were interpreted
as showing continuous colitis, discontinuous colitis, or no colitis. Results. In the 77 children with active Crohn's disease (CD) of the colon, the scans revealed discontinuous uptake in 63 children
and continuous uptake in 14. In the 29 children with ulcerative colitis (UC), 23 scans showed continuous uptake and 6 revealed
discontinuous uptake. Two of these 6 showed focal activity near the appendix, and subclinical appendicitis could not be excluded.
Another child was bleeding and the scan could have been misinterpreted as showing small- bowel inflammation. In the last three
patients, skip areas were clearly identifiable. In none of these last three patients were the biopsies typical of CD (i. e.,
no granuloma was identified) nor was inflammation patchy. In summary, of the 106 scans showing inflammation, 6 were classified
into the wrong group. Conclusion. These data show that WBC-Tc99m scanning can be useful in distinguishing discontinuous from continuous colitis.
Received: 20 November 1997 Accepted: 29 May 1998 相似文献
63.
Urodynamic assessment of the bashful bladder 总被引:2,自引:0,他引:2
PURPOSE: We prospectively studied the potential contribution of ambulatory urodynamic monitoring in men with urinary symptoms unable to initiate a void on conventional video cystometrography. MATERIALS AND METHODS: A total of 40 consecutive symptomatic men with a median International Prostate Symptom Score of 19 (range 1 to 29) and median age of 51.9 years (range 30 to 75) who were unable to void during video cystometrography underwent ambulatory urodynamic monitoring. Solid-state transducers mounted on silicone coated catheters were inserted urethrally and rectally, and connected to a portable recorder. Subjects voided in private into a specially designed flow meter, which they connected to the recording device. RESULTS: Of the patients 2 (5%) failed to attend ambulatory urodynamic monitoring, despite multiple reminders, and in 1 (2.5%) the trace was uninterpretable. Pressure flow data were available for the remaining 37 patients with mean plus or minus standard deviation 2.72+/-0.1 storage void cycles recorded per patient. All 6 patients (15%) with obstruction were older than 40 years. In 6 cases (15%) obstruction was equivocal and the remainder were unobstructed. Transurethral prostatic resection in 2 and urethrotomy in 1 of 6 patients with obstruction resulted in subjective and objective improvement. CONCLUSIONS: The bashful bladder syndrome was not associated with any specific urodynamic diagnosis. Ambulatory urodynamic monitoring will yield a urodynamic diagnosis in more than 90% of cases after failure to record void data on video cystometrography. A surgically correctable cause of symptoms can be found in about 20% of men older than 40 years. The contribution of ambulatory urodynamic monitoring compared to more conventional evaluation in men younger than 40 years is negligible. 相似文献
64.
65.
66.
67.
68.
Javier Mallol Dirceu Solé Viviana Aguirre Herberto Chong Nelson Rosario Luis García-Marcos 《The Journal of asthma》2013,50(11):1214-1222
Objective:To identify changes in the prevalence and severity of recurrent wheezing (RW) in infants using data obtained from two surveys administered seven years apart. Methods: A cross-sectional, international, population-based study in infants aged 12–15 months was conducted. Data were obtained from two surveys (S1 and S2, in 2005 and 2012, respectively) using the same methodology in three large Latin American cities: Curitiba (Brazil), São Paulo (Brazil), and Santiago (Chile). Results: A decrease in the overall prevalence of RW was identified between S1 (23.3%) and S2 (20.4%), p = 0.004, but it was mainly driven by the reduction observed in São Paulo; in Curitiba and Santiago, this change was not significant. The mean prevalence of the following RW severity indicators remained high and stable: severe wheezing episodes (56.9% in S1 and 54.2% in S2, p = 0.32) and emergency department (ED) visits for wheezing (S1 = 68.1%, S2 70.9%, p = 0.21). A significant increase in admissions for wheezing (21.1% to 26.7%, p = 0.004) was observed. In Curitiba and São Paulo, there were significant increases in the prevalence of physician-diagnosed asthma and in the use of inhaled corticosteroids and oral antileukotrienes. Conclusions: The prevalence and severity of RW during the first year of life remained high over time, with remarkably high rates of ED visits, admissions for wheezing and use of asthma medications. This study suggests the need for considering early asthma diagnosis and to establish an appropriate treatment in infants with recurrent and severe asthma-like symptoms. 相似文献
69.