全文获取类型
收费全文 | 2338篇 |
免费 | 166篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 102篇 |
儿科学 | 43篇 |
妇产科学 | 27篇 |
基础医学 | 269篇 |
口腔科学 | 71篇 |
临床医学 | 263篇 |
内科学 | 519篇 |
皮肤病学 | 66篇 |
神经病学 | 201篇 |
特种医学 | 47篇 |
外科学 | 354篇 |
综合类 | 23篇 |
预防医学 | 148篇 |
眼科学 | 15篇 |
药学 | 143篇 |
中国医学 | 5篇 |
肿瘤学 | 212篇 |
出版年
2023年 | 35篇 |
2022年 | 52篇 |
2021年 | 105篇 |
2020年 | 48篇 |
2019年 | 66篇 |
2018年 | 89篇 |
2017年 | 67篇 |
2016年 | 72篇 |
2015年 | 57篇 |
2014年 | 91篇 |
2013年 | 79篇 |
2012年 | 128篇 |
2011年 | 135篇 |
2010年 | 67篇 |
2009年 | 69篇 |
2008年 | 119篇 |
2007年 | 131篇 |
2006年 | 118篇 |
2005年 | 117篇 |
2004年 | 100篇 |
2003年 | 96篇 |
2002年 | 70篇 |
2001年 | 53篇 |
2000年 | 38篇 |
1999年 | 43篇 |
1998年 | 14篇 |
1996年 | 9篇 |
1995年 | 11篇 |
1994年 | 11篇 |
1992年 | 37篇 |
1991年 | 28篇 |
1990年 | 29篇 |
1989年 | 16篇 |
1988年 | 11篇 |
1987年 | 17篇 |
1986年 | 13篇 |
1985年 | 14篇 |
1984年 | 12篇 |
1979年 | 18篇 |
1976年 | 10篇 |
1975年 | 10篇 |
1974年 | 15篇 |
1973年 | 16篇 |
1972年 | 8篇 |
1971年 | 12篇 |
1970年 | 22篇 |
1969年 | 23篇 |
1968年 | 11篇 |
1967年 | 24篇 |
1966年 | 12篇 |
排序方式: 共有2508条查询结果,搜索用时 15 毫秒
111.
Takashi Ueguchi Yuko Tanaka Seiki Hamada Risa Kawamoto Yuji Ogata Mitsuhiro Matsumoto Hironobu Nakamura Takeshi Johkoh 《Magnetic resonance in medical sciences》2006,5(3):147-150
Air microbubbles have been investigated recently at high magnetic field strength (2 Tesla or greater) as potential MR susceptibility contrast agents. We used a phantom to measure their susceptibility at 1.5 T to clarify their usefulness for this purpose. The phantom, filled with fresh Levovist suspension at 4 different doses (67 to 125 mg/mL), was continuously scanned with a gradient-echo technique at a temporal resolution of 10 s. The transverse relaxation increase (R2*) by microbubbles demonstrated a time course of exponential decay at each dose (time-constant, 39 to 57 s). The dependency of R2* on microbubble volume fraction was linear, with a slope of 89 s-1 per percentage microbubble volume fraction. Our study represents the first step towards applying microbubbles as susceptibility contrast agents at 1.5 T. 相似文献
112.
Pneumoperitoneum (PP) is usually the result of perforation of the gastrointestinal (GI) tract with associated peritonitis. However, other rare causes, including spontaneous PP incidental to intrathoracic, intra-abdominal, gynecologic, and miscellaneous other origins not associated with a perforated GI tract have been described in the literature. Six cases of PP without any perforated GI tract are reported. Three patients with generalized peritonitis underwent exploratory laparotomy or laparoscopy when clinical examinations suggested an acute abdomen. At surgical procedure, perforated pyometra, perforated liver abscess and a ruptured necrotic lesion of a liver metastasis were documented in these patients, respectively. We also saw 3 PP patients not associated with peritonitis. Two patients with PP caused by pneumatosis cystoides intestinalis were encountered, 1 was managed conservatively and the other received diagnostic laparoscopy. A patient in whom pneumomediastinum and pneumoretroperitoneum were accompanied by PP caused by an alveolar rupture based on decreased pulmonary compliance due to malnutrition was managed conservatively. The history of the patient and knowledge of the less frequent causes of PP can possibly contribute towards refraining from exploratory laparotomy in the absence of peritonitis. 相似文献
113.
Background Jejunal pouch interposition (JPI) is known as a useful gastric replacement procedure after total gastrectomy. The JPI procedure,
however, has not been applicable to laparoscopically assisted total gastrectomy (LATG) because of its technical complexity
and difficulty. This study aimed to describe our modified LATG/JPI technique, and to evaluate its feasibility, safety, and
early postoperative functional outcome.
Methods Between September 2002 and August 2003, LATG/JPI was attempted for five patients (3 men and 2 women) with early gastric cancers
in the upper portion of the stomach. The mean age of the patients was 57 years, and their BMI was 21 kg/m2. Using a 5-port technique, the gastric arteries were laparoscopically clipped and divided with adequate lymphatic dissection.
After completion of gastric resection, the anvil of a circular stapling device was placed in the esophageal stump. An 8-cm
minilaparotomy then was performed, and the 12-cm pouch was created extracorporeally in the “reverse U” fashion. The stapled
pouch-esophagostomy was performed under laparoscopic monitoring. The remainder of the procedure was accomplished under direct
vision.
Results All cases were managed laparoscopically without any complications. The mean operating time was 407 min, and the blood loss
was 279 ml. All the patients showed rapid and uneventful recovery. Postoperative studies, including dual scintigraphy, showed
that all jejunal pouches were satisfactorily functioning.
Conclusions This study showed LATG/JPI to be feasible and safe. With technical modifications, LATG/JPI can become a potentially effective
option for improving patients’ quality of life after total gastrectomy. 相似文献
114.
Zsolt Csenki Anita Risa Dorottya Srkny Edina Garai Ildik Bata-Vidcs Erzsbet Baka Andrs Szekeres Mnika Varga Andrs cs Jeffrey Griffitts Katalin Bakos Ills Bock Istvn Szab Balzs Kriszt Bla Urbnyi Jzsef Kukolya 《Toxins》2022,14(4)
Aflatoxin B1 (AFB1) is a potent mycotoxin and natural carcinogen. The primary producers of AFB1 are Aspergillus flavus and A. parasiticus. Sterigmatocystin (STC), another mycotoxin, shares its biosynthetic pathway with aflatoxins. While there are abundant data on the biological effects of AFB1, STC is not well characterised. According to published data, AFB1 is more harmful to biological systems than STC. It has been suggested that STC is about one-tenth as potent a mutagen as AFB1 as measured by the Ames test. In this research, the biological effects of S9 rat liver homogenate-activated and non-activated STC and AFB1 were compared using two different biomonitoring systems, SOS-Chromotest and a recently developed microinjection zebrafish embryo method. When comparing the treatments, activated STC caused the highest mortality and number of DNA strand breaks across all injected volumes. Based on the E. coli SOS-Chromotest, the two toxins exerted the same genotoxicities. Moreover, according to the newly developed zebrafish microinjection method, STC appeared more toxic than AFB1. The scarce information correlating AFB1 and STC toxicity suggests that AFB1 is a more potent genotoxin than STC. Our findings contradict this assumption and illustrate the need for more complex biomonitoring systems for mycotoxin risk assessment. 相似文献
115.
116.
117.
118.
Veronica M. LoFaso MD MSN Risa Breckman LCSW Carol F. Capello PhD Byron Demopoulos MD Ronald D. Adelman MD 《Journal of the American Geriatrics Society》2010,58(2):346-351
As the number of people living with chronic illness in the United States rises, it is imperative that medical school prepare physicians who are capable of caring for these patients. This article outlines a creative educational intervention to teach third‐ and fourth‐year medical students about caring for chronically ill people. All students at Weill Medical College, Cornell University, make home visits to homebound older adults with an interdisciplinary team as part of a mandatory Primary Care Clerkship. Under their guidance, students observe the myriad challenges facing homebound older adults. Afterward, students create a project, using original or found art, to express their reactions and thoughts. Students present projects to peers in a small group, with multidisciplinary faculty mentors framing the discussion. To evaluate the intervention, students responded to a nine‐item questionnaire and a series of open‐ended questions. Quantitative and qualitative analyses show consistently strong positive responses to the experience. Most students (95.0%) felt that they learned about the complexities of chronic illness care from their home visits. The opportunity to express reactions through a creative project received positive responses with 97.0% of students responding favorably. Ninety‐seven percent felt that the discussions with colleagues and faculty increased knowledge of chronic illness care. Nearly all (97.0%) felt they had a better understanding of team and that attitudes toward the chronically ill were positively affected. The coupling of the creative arts with home visits is an effective tool for teaching about chronic illness and may be a useful model for medical schools interested in expanding their chronic illness curriculum. 相似文献
119.
120.
Masamune Higashigawa Yukako Kawasaki Noriko Yodoya Yusuke Omori Yuji Nashida Yoshio Amemiya Takashi Fujiwara Masakazu Inoue 《Pediatrics international》2009,51(5):684-686
Background: Few data are available for the recent occurrence of Mycoplasma infections in children in Japan. The purpose of the present study was therefore to identify the prevalence of Mycoplasma infections in children in Japan.
Methods: IgM antibodies to M. pneumoniae were prospectively determined using the Meridian ImmunoCard Mycoplasma test in hospitalized patients with lower respiratory tract infections between January 2004 and June 2007. A total of 858 hospitalized patients aged 0–15 years (445 male, 413 female), diagnosed as having acute pneumonia or bronchitis, were enrolled. The number of patients with pneumonia or bronchitis was 331 (male/female, 167/164) and 527 (male/female/ 278/249), respectively. Two hundred and five of the 858 patients (23.9%) were ImmunoCard positive. Of the 205 patients, 121 children and 84 children were diagnosed as having pneumonia and bronchitis, respectively. One hundred and forty-three of the 727 patients (19.7%) <5 years of age were ImmunoCard test positive.
Conclusions: M. pneumoniae infection is not rare in children aged <5 years in Japan. 相似文献
Methods: IgM antibodies to M. pneumoniae were prospectively determined using the Meridian ImmunoCard Mycoplasma test in hospitalized patients with lower respiratory tract infections between January 2004 and June 2007. A total of 858 hospitalized patients aged 0–15 years (445 male, 413 female), diagnosed as having acute pneumonia or bronchitis, were enrolled. The number of patients with pneumonia or bronchitis was 331 (male/female, 167/164) and 527 (male/female/ 278/249), respectively. Two hundred and five of the 858 patients (23.9%) were ImmunoCard positive. Of the 205 patients, 121 children and 84 children were diagnosed as having pneumonia and bronchitis, respectively. One hundred and forty-three of the 727 patients (19.7%) <5 years of age were ImmunoCard test positive.
Conclusions: M. pneumoniae infection is not rare in children aged <5 years in Japan. 相似文献