全文获取类型
收费全文 | 27994篇 |
免费 | 2348篇 |
国内免费 | 105篇 |
专业分类
耳鼻咽喉 | 337篇 |
儿科学 | 794篇 |
妇产科学 | 585篇 |
基础医学 | 4255篇 |
口腔科学 | 1083篇 |
临床医学 | 2406篇 |
内科学 | 6421篇 |
皮肤病学 | 650篇 |
神经病学 | 2907篇 |
特种医学 | 853篇 |
外科学 | 3386篇 |
综合类 | 150篇 |
一般理论 | 15篇 |
预防医学 | 2221篇 |
眼科学 | 445篇 |
药学 | 1809篇 |
中国医学 | 97篇 |
肿瘤学 | 2033篇 |
出版年
2023年 | 202篇 |
2022年 | 500篇 |
2021年 | 972篇 |
2020年 | 587篇 |
2019年 | 836篇 |
2018年 | 984篇 |
2017年 | 745篇 |
2016年 | 819篇 |
2015年 | 889篇 |
2014年 | 1116篇 |
2013年 | 1358篇 |
2012年 | 2022篇 |
2011年 | 2059篇 |
2010年 | 1241篇 |
2009年 | 1036篇 |
2008年 | 1550篇 |
2007年 | 1698篇 |
2006年 | 1463篇 |
2005年 | 1433篇 |
2004年 | 1298篇 |
2003年 | 1126篇 |
2002年 | 1038篇 |
2001年 | 492篇 |
2000年 | 450篇 |
1999年 | 461篇 |
1998年 | 247篇 |
1997年 | 242篇 |
1996年 | 174篇 |
1995年 | 166篇 |
1994年 | 147篇 |
1993年 | 134篇 |
1992年 | 286篇 |
1991年 | 266篇 |
1990年 | 229篇 |
1989年 | 239篇 |
1988年 | 206篇 |
1987年 | 179篇 |
1986年 | 201篇 |
1985年 | 197篇 |
1984年 | 136篇 |
1983年 | 119篇 |
1982年 | 67篇 |
1981年 | 73篇 |
1979年 | 86篇 |
1978年 | 76篇 |
1976年 | 50篇 |
1975年 | 58篇 |
1974年 | 44篇 |
1973年 | 60篇 |
1972年 | 51篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
Ariel Paracampo Marina Solis Carlos Bonetto 《International journal of environmental health research》2015,25(1):96-103
Chlorpyrifos is the most used insecticide in Argentina. Cnesterodon decemmaculatus is a widely distributed, endemic fish from Neotropical America. It attains high densities in the shallow water assemblages of Argentina and Brazil. The aim of this study was to assess the acute toxicity of chlorpyrifos to C. decemmaculatus. The mean 96-h LC50 of three independent determinations was 105.3 (±?3.1) μg/L. Sublethal effects were observed. Swimming behavioral changes at each chlorpyrifos exposure concentration were reported. C. decemmaculatus represents a good model for ecotoxicological risk assessment. 相似文献
6.
7.
Dan Azagury Tara E Mokhtari Luis Garcia Ulysses S Rosas Trit Garg Homero Rivas John Morton 《Surgery》2019,165(3):565-570
Background
Laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding all lead to substantial weight loss in obese patients. Long-term weight loss can be highly variable beyond 1-year postsurgery. This study examines and compares the frequency distribution of weight loss and lack of treatment effect rates after laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding.Methods
A total of 1,331 consecutive patients at a single academic institution were reviewed from a prospectively collected database. Preoperative data collected included demographics, body mass index, and percent excess weight loss. Postoperative BMI and %EWL were collected at 12, 24, and 36 months. Percent excess weight loss was analyzed by the percentiles of excess weight lost, and the distribution of percent excess weight loss was evaluated in 10% increments. Lack of a successful treatment effect was defined as <25% excess weight loss.Results
Of the 1,331 patients, 72.4% (963) underwent laparoscopic Roux-en-Y gastric bypass, 18.3% (243) laparoscopic sleeve gastrectomy, and 9.4%(125) laparoscopic adjustable gastric banding. Mean percent excess weight loss was greatest for laparoscopic Roux-en-Y gastric bypass, followed by laparoscopic sleeve gastrectomy, and then by laparoscopic adjustable gastric banding at every time point: at 2 years mean percent excess weight loss was 77.9± 24.4 for laparoscopic Roux-en-Y gastric bypass, 50.8 ± 25.8 for laparoscopic sleeve gastrectomy, and 40.8± 25.9 for laparoscopic adjustable gastric banding (P < .0001). The rates of a successful treatment effect s for laparoscopic Roux-en-Y gastric bypass, laparoscopic sleeve gastrectomy, and laparoscopic adjustable gastric banding were 0.9%, 5.2%, and 24.3% at 1 year; 0.3%, 11.1%, and 26.0% at 2 years; and 1.0%, 25.3%, and 30.2% at 3 years. At 1 year, the odds ratio of lack of a successful treatment effect of laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass was 6.305 (2.125–19.08; P?=?.0004), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass was 36.552 (15.64–95.71; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy was 5.791 (2.519–14.599; P < .0001). At 2 years, the odds ratio for laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass increased to 70.7 (9.4–531.7; P < .0001), the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic Roux-en-Y gastric bypass increased to 128.1 (16.8–974.3; P < .0001), and the odds ratio for laparoscopic adjustable gastric banding versus laparoscopic sleeve gastrectomy decreased to 1.8 (0.9–3.6; P?=?.09).Conclusion
This study emphasizes the existing variability in weight loss across bariatric procedures as well as in the lack of a treatment effect for each procedure. Although laparoscopic adjustable gastric banding has the greatest rate of a lack of a successful treatment effect, the rate remained stable over 3 years postoperatively. Laparoscopic sleeve gastrectomy showed a doubling in the rate of a lack of a successful treatment effect every year reaching 25% at year 3. The rates for lack of a successful treatment effect for laparoscopic Roux-en-Y gastric bypass remained stable at about 1% for the first 3 years postoperatively. 相似文献8.
9.
10.
Luis Veloza Cristina Teixido Natalia Castrejon Fina Climent Ana Carri Marta Marginet Davide Soldini Blanca Gonzlez‐Farr Inmaculada Ribera‐Cortada Armando Lopez‐Guillermo Eva Gonzlez‐Barca Adriana Sierra Mileyka Herrera Cndida Gmez Adriana Garcia Olga Balagu Elias Campo Antonio Martinez 《Histopathology》2019,75(6):799-812