全文获取类型
收费全文 | 27165篇 |
免费 | 1796篇 |
国内免费 | 295篇 |
专业分类
耳鼻咽喉 | 424篇 |
儿科学 | 417篇 |
妇产科学 | 591篇 |
基础医学 | 3947篇 |
口腔科学 | 700篇 |
临床医学 | 2359篇 |
内科学 | 5155篇 |
皮肤病学 | 587篇 |
神经病学 | 2020篇 |
特种医学 | 1619篇 |
外科学 | 4358篇 |
综合类 | 313篇 |
一般理论 | 10篇 |
预防医学 | 1114篇 |
眼科学 | 664篇 |
药学 | 2393篇 |
1篇 | |
中国医学 | 270篇 |
肿瘤学 | 2314篇 |
出版年
2023年 | 163篇 |
2022年 | 384篇 |
2021年 | 709篇 |
2020年 | 387篇 |
2019年 | 663篇 |
2018年 | 720篇 |
2017年 | 596篇 |
2016年 | 691篇 |
2015年 | 1026篇 |
2014年 | 1264篇 |
2013年 | 1431篇 |
2012年 | 2132篇 |
2011年 | 2092篇 |
2010年 | 1302篇 |
2009年 | 1195篇 |
2008年 | 1631篇 |
2007年 | 1585篇 |
2006年 | 1463篇 |
2005年 | 1386篇 |
2004年 | 1244篇 |
2003年 | 1083篇 |
2002年 | 956篇 |
2001年 | 779篇 |
2000年 | 762篇 |
1999年 | 603篇 |
1998年 | 225篇 |
1997年 | 219篇 |
1996年 | 182篇 |
1995年 | 156篇 |
1994年 | 134篇 |
1993年 | 112篇 |
1992年 | 247篇 |
1991年 | 193篇 |
1990年 | 178篇 |
1989年 | 171篇 |
1988年 | 148篇 |
1987年 | 104篇 |
1986年 | 97篇 |
1985年 | 70篇 |
1984年 | 78篇 |
1983年 | 50篇 |
1982年 | 52篇 |
1981年 | 44篇 |
1980年 | 43篇 |
1979年 | 56篇 |
1978年 | 44篇 |
1977年 | 46篇 |
1976年 | 38篇 |
1972年 | 44篇 |
1971年 | 42篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
2.
Laparoscopic surgery has several advantages over traditional surgery because it has been shown to be less invasive. The next logical step in the evolution of minimally invasive surgery may be to eliminate all abdominal incisions. The natural orifices provide a port of entry via the gastrointestinal tract to the peritoneal cavity. This approach would require the creation of a perforation, which is considered to be a major complication of endoscopy with significant morbidity and mortality. However, there are several recent studies that have described the technical feasibility and safety of a per‐oral transgastric approach to the peritoneal cavity using conventional endoscopes. Theoretically, this approach could reduce postoperative abdominal wall pain, wound infection, hernia formation, and adhesions. This article aims to summarize the current status of transgastric surgery, currently referred to as natural orifice transluminal endoscopic surgery (NOTES), and to address some of its future challenges. 相似文献
3.
4.
5.
Vincent Chung Liang Liu Zhaoxiang Bian Zhongzhen Zhao Wai Leuk Fong Wan Fung Kum Jing Gao Min Li 《Movement disorders》2006,21(10):1709-1715
The objective of this study is to assess the efficacy and safety of herbal medicines (HMs), as a monotherapy or adjunct therapy, compared to placebo or conventional approaches in the treatment of idiopathic Parkinson's disease (PD). We conducted a systematic review of randomized controlled trials from both conventional and alternative medicine sources. Outcome measures were overall improvement, quality of life, reduction of levodopa dose, and adverse events. Nine studies were included, each testing a different HM. Six of the trials had limited internal validity due to major flaws in design, including the lack of proper randomization; insufficient blinding; unclear inclusive criteria in terms of diagnostic criteria, baseline staging, and duration of disease; lack of proper sample size calculation; and insufficient data analysis. Imbalances in gender and ethnicity among the patients in the included trials were observed. No major adverse events emerged, and no specific pattern was detected from the trials describing such data. In addition to major methodological defects, heterogeneity in (1) HM tested, (2) control treatment, and (3) outcome measure hindered in-depth data analysis and synthesis. Current evidence is insufficient to evaluate the efficacy and safety of various HMs. Further studies with improved trial design and reporting, with assessment on cost-effectiveness, quality of life, and qualitative data are warranted. 相似文献
6.
A new range of stand magnifiers has been released by the COIL company in the United Kingdom. Examination of these magnifiers reveals that they fail to deliver the rated magnifications labelled prominently on the appliances, as a result of the manufacturer's conformance with the requirements of the German DIN standard and the use of back vertex power (F'v) rather than equivalent dioptric power (Fm) of the magnifier. In this study we provide information on the optometric parameters of these new stand magnifiers that will assist the more accurate specification of improvements in vision expected from their use. 相似文献
7.
Probable gas embolism during operative hysteroscopy caused by products of combustion 总被引:8,自引:0,他引:8
Ngozi Imasogie Ron Crago Nicholas A. Leyland Frances Chung 《Journal canadien d'anesthésie》2002,49(10):1044-1047
PURPOSE: Gas embolism is a rare but well documented entity during operative hysteroscopy, with an incidence of 10-50%. Catastrophic outcomes occur at a rate of three in 17,000 procedures. The purpose of this report is to present a non-fatal case of gas embolism probably caused by the gaseous products of combustion. CLINICAL FEATURES: A 50-yr-old woman with a history of menorrhagia was scheduled for hysteroscopy and endometrial ablation and polypectomy. Fifteen minutes into the procedure, with the patient in lithotomy position, 20 degree head down tilt, and breathing spontaneously, a sudden oxygen desaturation occurred from 97% to 87%. The patient's end-tidal carbon dioxide dropped from 46 mmHg to 27 mmHg. The patient's breathing pattern remained normal, respiratory rate remained 11-12 breaths x min(-1) but amplitude of the reservoir bag movement was increased. Cardiovascular variables remained stable. She responded rapidly to 100% oxygen and made an uneventful recovery. Having ruled out other possible causes, we concluded gas embolism was responsible for the fall in oxygen saturation and end-tidal CO(2). CONCLUSION: With all the precautions in place to minimize the likelihood of fluid overload and ambient air embolism occurring, we surmised that products of combustion were the cause of the gas embolism. During endometrial ablation, gaseous products of combustion, mainly carbon dioxide, accumulate. The gases may then contribute to the rise in uterine pressure that occurs as irrigation fluid enters the uterus and this rise in pressure in turn encourages passage of gas into the open venous sinuses. 相似文献
8.
P Brennan D Johnson S Rider N Cone M Goldman A Buckpitt H Chung 《Biopharmaceutics & drug disposition》1991,12(7):547-556
The dermal absorption of niclosamide, a drug shown to prevent Schistosomiasis by blocking the dermal penetration of cercariae, has been examined in Sinclair minipigs and rats. Radioactivity in the urine and feces collected daily for 7 days after application of 14C-niclosamide accounted for less than 2 per cent and 10 per cent of the labelled compound applied to pig and rat skin, respectively. Approximately 20 per cent of the radioactivity from the dose solution was recovered on the skin excised from the area of application in both minipigs and rats. No radioactivity was detected in organs removed from the pig 7 days after application of radiolabelled drug while less than 6 per cent of the dose could be accounted for in the rat organs/carcass. Radioactivity in swine blood, removed 0.5, 1, 2, 4 and at 24 h intervals after dosing, was at or below three times background in all of the samples. Total recovery of the applied radioactivity was 78 per cent in pigs and 57 per cent in rats. These studies indicate that niclosamide is very poorly absorbed after dermal application. The results are consistent with earlier comparative studies showing that dermal penetration of xenobiotics in rats is generally higher than in swine. 相似文献
9.
YS Nagar S Singh V Sawlani L Pal K Dimri P Lal 《Journal of Medical Imaging and Radiation Oncology》2005,49(2):160-162
A rare case of an advanced primary broad ligament carcinoma is discussed, with a review of the literature regarding its incidence, presentation and management. This patient showed a complete response to adjuvant cisplatin-based chemotherapy following panhysterectomy and is presently without any evidence of disease, 15 months after completion of her treatment. 相似文献
10.
With the increased use of indwelling central venous catheters, increasing numbers of cases of Rhodotorula fungemia have been observed in patients with neoplasia and neutropenia. In most patients with catheter-related Rhodotorula fungemia, the condition has been treated with broadspectrum antibiotics. We report two cases of central venous catheter-related
Rhodotorula rubra fungemia that occurred in patients with acute myeloblastic leukemia. Both patients were in a state of neutropenia. One patient
was treated with amphotericin B and his central venous catheter was removed, but he died of Klebsiella pneumoniae bacteremia. The other patient was treated with amphotericin B and discharged, with a central venous catheter, after recovery
from neutropenia. Although the management of catheter-related Rhodotorula fungemia infections remains controversial, resolution of the underlying disease is more important than catheter removal for
recovery from Rhodotorula rubra fungemia.
Received: August 22, 2001 / Accepted: October 8, 2001 相似文献