全文获取类型
收费全文 | 29503篇 |
免费 | 1318篇 |
国内免费 | 164篇 |
专业分类
耳鼻咽喉 | 274篇 |
儿科学 | 547篇 |
妇产科学 | 472篇 |
基础医学 | 3955篇 |
口腔科学 | 583篇 |
临床医学 | 1771篇 |
内科学 | 7313篇 |
皮肤病学 | 399篇 |
神经病学 | 2423篇 |
特种医学 | 1162篇 |
外科学 | 4989篇 |
综合类 | 136篇 |
一般理论 | 5篇 |
预防医学 | 890篇 |
眼科学 | 559篇 |
药学 | 1707篇 |
中国医学 | 63篇 |
肿瘤学 | 3737篇 |
出版年
2023年 | 137篇 |
2022年 | 318篇 |
2021年 | 574篇 |
2020年 | 304篇 |
2019年 | 406篇 |
2018年 | 536篇 |
2017年 | 416篇 |
2016年 | 522篇 |
2015年 | 517篇 |
2014年 | 698篇 |
2013年 | 864篇 |
2012年 | 1481篇 |
2011年 | 1514篇 |
2010年 | 873篇 |
2009年 | 748篇 |
2008年 | 1365篇 |
2007年 | 1526篇 |
2006年 | 1478篇 |
2005年 | 1461篇 |
2004年 | 1392篇 |
2003年 | 1357篇 |
2002年 | 1448篇 |
2001年 | 751篇 |
2000年 | 807篇 |
1999年 | 772篇 |
1998年 | 413篇 |
1997年 | 330篇 |
1996年 | 301篇 |
1995年 | 290篇 |
1994年 | 271篇 |
1993年 | 256篇 |
1992年 | 680篇 |
1991年 | 610篇 |
1990年 | 583篇 |
1989年 | 596篇 |
1988年 | 544篇 |
1987年 | 523篇 |
1986年 | 454篇 |
1985年 | 454篇 |
1984年 | 270篇 |
1983年 | 225篇 |
1982年 | 109篇 |
1981年 | 102篇 |
1979年 | 235篇 |
1978年 | 138篇 |
1977年 | 111篇 |
1975年 | 103篇 |
1973年 | 103篇 |
1970年 | 108篇 |
1969年 | 118篇 |
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
1.
Zhenzhen Zhang Mark Garzotto Tomasz M. Beer Philippe Thuillier Stephen Lieberman Motomi Mori 《Nutrition and cancer》2016,68(8):1309-1319
Animal and human studies suggest fish oil and green tea may have protective effect on prostate cancer. Fatty acid synthase (FAS) has been hypothesized to be linked to chemoprotective effects of both compounds. This study evaluated the independent and joint effects of fish oil (FO) and green tea supplement (epigallocatechin-3-gallate, EGCG) on FAS and Ki-67 levels in prostate tissue. Through a double-blinded, randomized controlled trial with 2 × 2 factorial design, 89 men scheduled for repeat prostate biopsy following an initial negative prostate biopsy were randomized into either FO alone (1.9 g DHA + EPA/day), EGCG alone (600 mg/day), a combination of FO and EGCG, or placebo. We used linear mixed-effects models to test the differences of prostate tissue FAS and Ki-67 by immunohistochemistry between pre- and post-intervention within each group, as well as between treatment groups. Results did not show significant difference among treatment groups in pre-to-post-intervention changes of FAS (P = 0.69) or Ki-67 (P = 0.26). Comparing placebo group with any of the treatment groups, we did not find significant difference in FAS or Ki-67 changes (all P > 0.05). Results indicate FO or EGCG supplementation for a short duration may not be sufficient to produce biologically meaningful changes in FAS or Ki-67 levels in prostate tissue. 相似文献
2.
3.
Masaru Sasaki Tsuyoshi Takahashi Soichiro Funaki Koji Tanaka Yasuhiro Miyazaki Naoko Ose Tomoki Makino Yukinori Kurokawa Makoto Yamasaki Kiyokazu Nakajima Yasushi Shintani Masaki Mori Yuichiro Doki 《Asian journal of endoscopic surgery》2021,14(1):116-119
We report a case of a diaphragmatic hernia after a heart transplant operation. A 43-year-old woman, who underwent orthotropic heart transplantation for hypertrophic cadiomyopathy two year earlier, presented with vomiting and epigastric pain. A computed tomography scan showed that the stomach and transverse colon were dislocated in the left thoracic cavity. We diagnosed left diaphragmatic hernia incarceration and performed laparoscopic repair of the diaphragmatic hernia. A 12 × 8 cm diaphragmatic defect was found intraoperatively on the ventrolateral aspect of the left diaphragm, and the stomach with volvulus had herniated into the thorax through the defect. The hernia was considered to be iatrogenic. The diaphragmatic defect was large, and the diaphragm was thinning. We closed the defect by mesh repair. Laparoscopic mesh repair of the diaphragmatic hernia could be performed safely and with minimal invasiveness. 相似文献
4.
5.
6.
7.
Eitaro Ito Akihiro Takai Yoshinori Imai Hiromi Otani Yoshihiro Onishi Yosuke Yamamoto Kohei Ogawa Taiji Tohyama Shunichi Fukuhara Yasutsugu Takada 《Surgery》2019,165(2):353-359
Background
Controversy continues as to whether single-incision laparoscopic cholecystectomy, with the somewhat larger incision at the umbilicus, may lead to a worse postoperative quality of life and more pain compared with the more classic 4-port laparoscopic cholecystectomy. The aim of this study was to compare single-incision and 4-port laparoscopic cholecystectomy from the perspective of quality of life.Methods
This study was a multicenter, parallel-group, open-label, randomized clinical trial. A total of 120 patients who were scheduled to undergo elective cholecystectomy were randomly assigned 1:1 into the single-incision laparoscopic cholecystectomy or the 4-port laparoscopic cholecystectomy group and then assessed continuously for 2 weeks during the postoperative period. The primary outcome was quality of life, defined as the time to resume normal daily activities. Postoperative pain was also assessed. To explore the heterogeneity of treatment effects, we assessed the interactions of sex, age, and working status on recovery time.Results
A total of 58 patients in the single-incision group and 53 in the 4-port group (n?=?111, 47 male, mean age 57 years) were analyzed. The mean time to resume daily activities was 10.2 days and 8.8 days, respectively, for single-incision and 4-port laparoscopic cholecystectomy (95% confidence interval –0.4 to 3.2, P?=?.12). Similarly, the time to relief from postoperative pain did not differ significantly between the groups. Statistically insignificant but qualitative interactions were noted; in the subgroups of women, full-time workers, and patients younger than 60 years, recovery tended to be slower after single-incision laparoscopic cholecystectomy.Conclusion
Postoperative quality of life did not differ substantially between single-incision laparoscopic cholecystectomy and 4-port laparoscopic cholecystectomy. Patients younger than 60 years, women, and full-time workers tended to have a somewhat slower recovery after single-incision laparoscopic cholecystectomy. 相似文献8.
Kei Kamide Yoshihiro Kokubo Hironori Hanada Junko Nagura Jin Yang Shin Takiuchi Chihiro Tanaka Mariko Banno Yoshikazu Miwa Masayoshi Yoshii Tetsutaro Matayoshi Hisayo Yasuda Takeshi Horio Akira Okayama Hitonobu Tomoike Yuhei Kawano Toshiyuki Miyata 《Hypertension research》2006,29(4):243-252
Mutations in the gene encoding 11beta-hydroxysteroid dehydrogenase type 2, HSD11B2, cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, defective HSD11B2 enzyme activity results in overstimulation of the mineralocorticoid receptor (MR) by cortisol, causing sodium retention, hypokalemia, and salt-dependent hypertension. Here, we have studied whether genetic variations in HDS11B2 are implicated in essential hypertension in Japanese hypertensives and the general population. By sequencing the entire coding region and the promoter region of HDS11B2 in 953 Japanese hypertensives, we identified five missense mutations in 11 patients (L14F, n = 5; R74H, n = 1; R147H, n = 3; T156I, n = 1; R335H, n = 1) and one novel frameshift mutation (4884Gdel, n = 1) in a heterozygous state, in addition to 19 genetic variations. All genetic variations identified were rare, with minor allele frequencies less than 0.005. Four of 12 patients with the missense/frameshift mutations showed renal failure. Four missense mutations, L14F, R74H, R147H, and R335H, were successfully genotyped in the general population, with a sample size of 3,655 individuals (2,175 normotensives and 1,480 hypertensives). Mutations L14F, R74H, R147H, and R335H were identified in hypertensives (n = 6, 8, 3, and 0, respectively) and normotensives (n = 8, 12, 5, and 0, respectively) with a similar frequency, suggesting that these missense mutations may not strongly affect the etiology of essential hypertension. Since the allele frequency of all of the genetic variations identified in this study was rare, an association study was not conducted. Taken together, our results indicate that missense mutations in HSD11B2 do not substantially contribute to essential hypertension in Japanese. 相似文献
9.
10.
Takako Miyamae Masaaki Mori Yasuji Inamo Youichi Kohno Shuji Takei Motoharu Maeda Takuji Murata Shuji Nakata Hiroshi Kawai Yukiko Hirano Yukiji Date Katsuhiko Kitamura Shumpei Yokota 《Ryūmachi》2003,43(3):538-543
OBJECTIVES: To reveal the frequency and the clinical characteristics of dystrophic calcification that occurs in children with juvenile dermatomyositis, multi-center analysis was constructed. METHOD: Fifty children with JDM were enrolled, and 14 of them (28.0%) were complicated with calcinosis. Clinical symptoms and laboratory tests at onset, initial therapy and disease course were compared in children with and without calcinosis. RESULTS: The mean age of the onset of calcinosis was 4.78 +/- 3.33 years, and it was younger than those of children without calcinosis (8.66 +/- 3.85 years) (P = 0.0017). No differences of clinical manifestation except Gower's sign were observed. The frequency of positive anti-nuclear antibody was 7.1% in children with calcinosis and 52.9% without calcinosis (P = 0.0112). The initial therapy of methylprednisolon pulses gave no effects on prognosis of calcium deposition. The calcinosis appeared in 1.56 +/- 1.91 year after the onset of the disease. The various types of calcium deposition including large tumorous clumps, subcutaneous plaques or nodules, sheet-type calcification were deserved. They appeared over knee joints (64.3%), elbow joint (64.3%), and hip processes (50.0%). Calcinosis affecting the subcutaneous tissues frequently resulted in painful superficial ulceration of the overlying skin (42.9%), local infection (50.0%), and limitation of joint movement (14.3%). Although aluminum phosphate was effective in 2 children among 7, no other effective treatment was recommended. In 5 cases, surgical removal of tumorous clumps was operated. Thus, juvenile dermatomyositis is frequently complicated with calcinosis. This type of calcinosis was found to be unlikely to resolve completely, and resulted in severe disability in children. 相似文献