全文获取类型
收费全文 | 3237篇 |
免费 | 385篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 25篇 |
儿科学 | 120篇 |
妇产科学 | 99篇 |
基础医学 | 345篇 |
口腔科学 | 193篇 |
临床医学 | 285篇 |
内科学 | 863篇 |
皮肤病学 | 53篇 |
神经病学 | 139篇 |
特种医学 | 107篇 |
外科学 | 405篇 |
综合类 | 80篇 |
预防医学 | 312篇 |
眼科学 | 149篇 |
药学 | 256篇 |
中国医学 | 13篇 |
肿瘤学 | 195篇 |
出版年
2023年 | 45篇 |
2022年 | 134篇 |
2021年 | 183篇 |
2020年 | 116篇 |
2019年 | 166篇 |
2018年 | 198篇 |
2017年 | 133篇 |
2016年 | 145篇 |
2015年 | 140篇 |
2014年 | 177篇 |
2013年 | 203篇 |
2012年 | 268篇 |
2011年 | 261篇 |
2010年 | 157篇 |
2009年 | 108篇 |
2008年 | 154篇 |
2007年 | 131篇 |
2006年 | 129篇 |
2005年 | 141篇 |
2004年 | 103篇 |
2003年 | 77篇 |
2002年 | 76篇 |
2001年 | 25篇 |
2000年 | 37篇 |
1999年 | 40篇 |
1998年 | 27篇 |
1997年 | 20篇 |
1996年 | 16篇 |
1995年 | 12篇 |
1994年 | 7篇 |
1993年 | 17篇 |
1992年 | 21篇 |
1991年 | 23篇 |
1990年 | 24篇 |
1989年 | 16篇 |
1988年 | 17篇 |
1987年 | 16篇 |
1986年 | 12篇 |
1985年 | 5篇 |
1984年 | 10篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1978年 | 6篇 |
1976年 | 3篇 |
1973年 | 3篇 |
1971年 | 2篇 |
1970年 | 3篇 |
1967年 | 5篇 |
排序方式: 共有3639条查询结果,搜索用时 0 毫秒
51.
52.
Entire elimination of pharmaceutical drugs from waste- and domestic-waters has attracted great attention due to their potent adverse effects on human health, particularly the human immune system. Many risks have been related to the presence of different types of drugs at different concentrations in wastewater. These risks include antimicrobial resistance (AMR), endocrine action, hormonal activation of cancers, and photodegradation of drugs. In this study, new nanohybrid materials consisting of graphene oxide (GO) and oxidized carbon nanotubes (OCNTs) were developed to remove a well-known drug, namely, ranitidine that treats stomach ulcers and gastrointestinal (GI) reflux disease from aqueous solutions. The characterization of synthesized nanohybrid GO-OCNTs was performed using spectroscopic (FTIR, and XRD), thermogravimetric (TGA) and microscopic (SEM) techniques. Batch adsorption experiments were used to investigate the technical feasibility of using synthesized GO-OCNTs for the removal of ranitidine from aqueous solutions. The effects of different operating conditions such as contact time, nanohybrid mass, solution temperature, solution pH, % crosslinking agent, and GO-to-OCNT ratio on the entire elimination of ranitidine were investigated. The experimental results indicated that the removal of ranitidine was very efficient, where 98.3% removal of the drug from aqueous solutions was achieved with a drug uptake of 97.8 mg g−1. Moreover, the results indicated the optimum conditions for the removal of ranitidine, which are as follows: contact time = 140 minutes, nanohybrid GO-OCNT mass = 10 mg, solution temperature = 290 K, solution pH = 6.4, % crosslinking agent = 0.5%, and GO to O-CNT ratio = 1 : 4. The equilibrium data were fitted to different adsorption isotherms and Langmuir was found to best describe our data. Dynamic studies demonstrated that ranitidine adsorption followed pseudo-second order, and the thermodynamic parameters confirmed exothermic drug adsorption as well as the physisorption process.Entire elimination of pharmaceutical drugs from waste- and domestic-waters has attracted great attention due to their potent adverse effects on human health, particularly the human immune system. 相似文献
53.
54.
55.
56.
Offodile AC Lee SW Yoo J Whelan RL Moradi D Baxter R Arnell TD Nasar A Sonoda T Milsom JW Feingold DL 《Diseases of the colon and rectum》2008,51(11):1669-1674
Purpose The study investigated the impact of prior abdominal surgery on conversions and outcomes of laparoscopic right colectomy.
Methods A consecutive series of 414 patients with cancer or adenomas who underwent a laparoscopic right colectomy from March 1996
to November 2006 were studied for surgical conversions and outcomes. Conversion was defined as an incision length > 7 cm.
Results Patients with prior abdominal surgery (n = 191) were compared with patients with no prior abdominal surgery (n = 223), and
showed no significant differences in age, ASA classification, length of stay, operative time, blood loss, harvested nodes,
tumor size, and specimen length. Significantly more wound infections occurred in the prior abdominal surgery group (22 vs.12, P = 0.023). Body mass index > 30 showed a three-fold increased risk of conversion.
Fifteen percent of the no prior abdominal surgery patients and 17 percent of the prior abdominal surgery patients were converted
(P > 0.05). Conversion was associated with a longer mean length of stay (8.8 days) relative to laparoscopically completed cases
(6.3 days) regardless of prior abdominal surgery history (P < 0.0001).
Conclusions Laparoscopic right colectomy for neoplasia was not associated with a higher conversion rate or morbidity in patients with
prior abdominal surgery. Prior abdominal surgery is not a contraindication to laparoscopic right colectomy.
Presented at the 15th International Congress of the European Association of Endoscopic Surgery, Athens, Greece, July 4 to
7, 2007. 相似文献
57.
58.
59.
Hamady Dieng Rahimah Binti Hassan Ahmad Abu Hassan Idris Abd Ghani Fatimah Bt Abang Tomomitsu Satho Fumio Miake Hamdan Ahmad Yuki Fukumitsu Nur Aida Hashim Wan Fatma Zuharah Nur Faeza Abu Kassim Abdul Hafiz Ab Majid Rekha Selvarajoo Cirilo Nolasco-Hipolito Olaide Olawunmi Ajibola Andrew Alek Tuen 《Acta tropica》2015
Even with continuous vector control, dengue is still a growing threat to public health in Southeast Asia. Main causes comprise difficulties in identifying productive breeding sites and inappropriate targeted chemical interventions. In this region, rural families keep live birds in backyards and dengue mosquitoes have been reported in containers in the cages. To focus on this particular breeding site, we examined the capacity of bird fecal matter (BFM) from the spotted dove, to support Aedes albopictus larval growth. The impact of BFM larval uptake on some adult fitness traits influencing vectorial capacity was also investigated. In serial bioassays involving a high and low larval density (HD and LD), BFM and larval standard food (LSF) affected differently larval development. At HD, development was longer in the BFM environment. There were no appreciable mortality differences between the two treatments, which resulted in similar pupation and adult emergence successes. BFM treatment produced a better gender balance. There were comparable levels of blood uptake and egg production in BFM and LSF females at LD; that was not the case for the HD one, which resulted in bigger adults. BFM and LSF females displayed equivalent lifespans; in males, this parameter was shorter in those derived from the BFM/LD treatment. Taken together these results suggest that bird defecations successfully support the development of Ae. albopictus. Due to their cryptic aspects, containers used to supply water to encaged birds may not have been targeted by chemical interventions. 相似文献
60.
Abdulla Shehab Asim A. Elnour Adel Sadik Mahmoud Abu Mandil Ali AlShamsi Aesha Al Suwaidi AkshayaSrikanth Bhagavathula Pinar Erkekoglu Farah Hamad Saif K. Al Nuaimi 《Saudi medical journal》2015,36(11):1290-1298