首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2514篇
  免费   191篇
  国内免费   19篇
耳鼻咽喉   15篇
儿科学   80篇
妇产科学   37篇
基础医学   382篇
口腔科学   130篇
临床医学   203篇
内科学   607篇
皮肤病学   173篇
神经病学   154篇
特种医学   98篇
外科学   179篇
综合类   14篇
预防医学   154篇
眼科学   48篇
药学   200篇
中国医学   6篇
肿瘤学   244篇
  2024年   5篇
  2023年   24篇
  2022年   56篇
  2021年   82篇
  2020年   57篇
  2019年   57篇
  2018年   71篇
  2017年   80篇
  2016年   93篇
  2015年   83篇
  2014年   110篇
  2013年   117篇
  2012年   200篇
  2011年   208篇
  2010年   101篇
  2009年   110篇
  2008年   157篇
  2007年   165篇
  2006年   159篇
  2005年   143篇
  2004年   138篇
  2003年   117篇
  2002年   104篇
  2001年   22篇
  2000年   18篇
  1999年   22篇
  1998年   31篇
  1997年   17篇
  1996年   10篇
  1995年   8篇
  1994年   5篇
  1993年   8篇
  1992年   11篇
  1991年   9篇
  1990年   11篇
  1989年   12篇
  1988年   18篇
  1987年   10篇
  1986年   9篇
  1985年   6篇
  1984年   7篇
  1983年   7篇
  1982年   3篇
  1979年   8篇
  1977年   3篇
  1973年   7篇
  1970年   2篇
  1969年   3篇
  1968年   2篇
  1967年   3篇
排序方式: 共有2724条查询结果,搜索用时 0 毫秒
71.
72.
We reviewed 428 subjects with colorectal serrated lesions resected endoscopically or surgically at our institution. Colorectal serrated lesions were pathologically divided into 3 groups: hyperplastic polyp (HP), sessile serrated adenoma/polyp (SSA/P), and traditional serrated adenoma (TSA). SSA/P was detected frequently in the right colon and SSA/P was mainly flat-elevated. Cancers occurring in SSA/P were found more frequently than HP or TSA. The incidence of cancer in SSA/P was equivalent to that of cancer in traditional adenoma. Further studies are warranted to clarify clinicopathological features of serrated lesions of the colorectum.  相似文献   
73.

OBJECTIVE:

This research was designed as a pilot proof-of-concept study to evaluate the use of low-dose methadone in post-herpetic neuralgia patients who remained refractory after first and second line post-herpetic neuralgia treatments and had indications for adding an opioid agent to their current drug regimens.

METHODS:

This cross-over study was double blind and placebo controlled. Ten opioid naïve post-herpetic neuralgia patients received either methadone (5 mg bid) or placebo for three weeks, followed by a 15-day washout period and a second three-week treatment with either methadone or placebo, accordingly. Clinical evaluations were performed four times (before and after each three-week treatment period). The evaluations included the visual analogue scale, verbal category scale, daily activities scale, McGill pain questionnaire, adverse events profile, and evoked pain assessment. All patients provided written informed consent before being included in the study. ClinicalTrials.gov: NCT01752699

RESULTS:

Methadone, when compared to placebo, did not significantly affect the intensity of spontaneous pain, as measured by the visual analogue scale. The intensity of spontaneous pain was significantly decreased after the methadone treatment compared to placebo on the category verbal scale (50% improved after the methadone treatment, none after the placebo, p = 0.031). Evoked pain was reduced under methadone compared to placebo (50% improved after the methadone treatment, none after the placebo, p = 0.031). Allodynia reduction correlated with sleep improvement (r = 0.67, p = 0.030) during the methadone treatment. The side effects profile was similar between both treatments.

CONCLUSIONS:

Methadone seems to be safe and efficacious in post-herpetic neuralgia. It should be tried as an adjunctive treatment for post-herpetic neuralgia in larger prospective studies.  相似文献   
74.
75.
Primary strumal carcinoid tumor of the ovary (SCTO) is an extremely rare entity, though the survival rate is excellent if the disease is confined to one ovary. A case is presented here in which intraoperative squash smears in a 45‐year‐old woman with a left adnexal mass revealed dispersed or small clusters of neoplastic cells forming loosely cohesive gland‐like structures with abundant cytoplasm. The nuclear chromatin was finely granular with a “salt and pepper” appearance and occasional tiny nucleoli. The position of the nucleus presented a vaguely plasmacytoid appearance. Small fragments of thyroidal colloid‐like structures were also identified. A cytopathologic diagnosis of a SCTO was suggested. Further evaluation and immunohistochemical studies were conducted on formalin‐fixed, paraffin‐embedded material. Cords or nests of uniform cells with abundant cytoplasm, and eccentric nuclei with coarse chromatin and occasional colloidal tissue were identified on H&E sections. The tumor cells showed diffuse and strong cytoplasmic staining for chromogranin A, synaptophysin, CD56, and vimentin but were negative for calretinin, α‐inhibin or CDX2. The proliferative index with MIB‐1 was around 3%. Thyroidal colloid‐like structures were immunoreactive for thyroglobulin and TTF‐1 stains. The diagnosis of primary SCTO was confirmed based on cytopathologic, histopathological, and immunohistochemical results, and the location of the tumor. Awareness of the cytopathological findings of SCTO can assist in diagnosing this rare entity correctly. Diagn. Cytopathol. 2013;41:812–816. © 2011 Wiley Periodicals, Inc.  相似文献   
76.
77.
78.
79.
Background: Virus infection is an important risk factor for aggravation of childhood asthma. The objective of this study was to examine the effect of drugs on aggravation of asthma induced by a common cold. Methods: Asthma control was examined in a survey of 1,014 Japanese pediatric patients with bronchial asthma. The occurrence of common cold, asthma control, and drugs used for asthma control were investigated using a modified Childhood Asthma Control Test (C-ACT) for patients aged <4 years old and 4 to 11 years old, and an Asthma Control Test (ACT) for patients aged 12 to 15 years old. Results: The status of asthma control did not differ among the age groups. The prevalence of common cold and aggravation of asthma were significantly higher in patients aged <4 years old. Control of asthma following common cold-induced aggravation was significantly less effective in patients aged <4 years old compared to those aged ≥4 years old. In patients aged <4 years old with a common cold, asthma control was significantly more effective for those treated with leukotriene receptor antagonists (LTRAs) compared to treatment without LTRAs. Asthma control did not differ between patients who did or did not take inhaled corticosteroids or long-acting β2 stimulants. Conclusions: These findings showed a high prevalence of common cold in younger patients with childhood asthma and indicated that common cold can induce aggravation of asthma. LTRAs are useful for long-term asthma control in very young patients who develop an asthma attack due to a common cold.  相似文献   
80.
Aim: In liver resection, the temporary occlusion of the hepatoduodenal ligament (Pringle maneuver) is often used. However, the maneuver causes ischemia/reperfusion (I/R) injury in the remnant liver. Heme oxygenase (HO)‐1 has a cytoprotective role against this injury. Our aim is to investigate whether splenic artery ligation induces HO‐1 expression in the liver and ameliorates the hepatic I/R injury in partially hepatectomized rats. Methods: Rats underwent splenic artery ligation by occluding the main splenic artery. Two days later, the total hepatic ischemia (Pringle maneuver) was conducted, and then a two‐thirds partial hepatectomy (PH) was performed just before the start of reperfusion. HO inhibitor was twice injected s.c. at 3 and 16 h before the Pringle maneuver. HO‐1 levels were determined by western blotting. Liver injury was biochemically assessed. Results: In normal rats, HO‐1 was highly expressed in the spleen, but not in the liver. Splenic artery ligation induced HO‐1 in the livers. When rats underwent 20 and 30 min of Pringle maneuver/PH, survival rates were 28% and 8%, respectively. Splenic artery ligation significantly improved both the survival rates: 73% and 56%, respectively. Under these conditions, administration of HO‐1 inhibitor at least partly negated the efficacy of splenic artery ligation. Splenic artery ligation also increased the recovery rate of the remnant liver mass and platelet counts in Pringle maneuver/PH‐treated rats. Conclusion: Splenic artery ligation was significantly effective on the hepatic I/R injury in partially hepatectomized rats. Induction of HO‐1 may be at least partly involved in the improvement of this injury.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号