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   3842篇
  免费   194篇
  国内免费   32篇
耳鼻咽喉   15篇
儿科学   105篇
妇产科学   30篇
基础医学   443篇
口腔科学   77篇
临床医学   314篇
内科学   1057篇
皮肤病学   56篇
神经病学   257篇
特种医学   113篇
外科学   810篇
综合类   23篇
预防医学   78篇
眼科学   14篇
药学   272篇
中国医学   30篇
肿瘤学   374篇
  2023年   25篇
  2022年   46篇
  2021年   94篇
  2020年   67篇
  2019年   72篇
  2018年   88篇
  2017年   67篇
  2016年   62篇
  2015年   72篇
  2014年   107篇
  2013年   122篇
  2012年   223篇
  2011年   227篇
  2010年   108篇
  2009年   96篇
  2008年   208篇
  2007年   184篇
  2006年   191篇
  2005年   230篇
  2004年   208篇
  2003年   179篇
  2002年   185篇
  2001年   72篇
  2000年   88篇
  1999年   85篇
  1998年   67篇
  1997年   51篇
  1996年   41篇
  1995年   43篇
  1994年   35篇
  1993年   35篇
  1992年   62篇
  1991年   59篇
  1990年   61篇
  1989年   54篇
  1988年   45篇
  1987年   48篇
  1986年   37篇
  1985年   42篇
  1984年   32篇
  1983年   32篇
  1982年   17篇
  1981年   12篇
  1979年   19篇
  1978年   20篇
  1977年   19篇
  1974年   14篇
  1973年   13篇
  1971年   16篇
  1970年   19篇
排序方式: 共有4068条查询结果,搜索用时 15 毫秒
121.
The clinical characteristics and prognostic relevance of acute myeloid leukaemia (AML) with myelodysplastic features remains to be clarified in children. We prospectively examined 443 newly diagnosed patients in a multicentre clinical trial for paediatric de novo AML, and found ‘AML with myelodysplasia‐related changes’ (AML‐MRC) according to the 2008 World Health Organization classification in 93 (21·0%), in whom 59 were diagnosed from myelodysplasia‐related cytogenetics alone, 28 from multilineage dysplasia alone and six from a combination of both. Compared with 111 patients with ‘AML, not otherwise specified’ (AML‐NOS), patients with ‘AML‐MRC’ presented at a younger age, with a lower white blood cell count, higher incidence of 20–30% bone marrow blasts, unfavourable cytogenetics and a lower frequency of Fms‐like tyrosine kinase 3 internal tandem duplication (FLT3‐ITD), NPM1 and CEBPA mutations. Complete remission rate and 3‐year probability of event‐free survival were significantly worse in ‘AML‐MRC’ patients (67·7 vs. 85·6%, < 0·01, 37·1% vs. 53·8%, P = 0·02, respectively), but 3‐year overall survival and relapse‐free survival were comparable with ‘AML‐NOS’ patients. By multivariate analysis, FLT3‐ITD was solely associated with worse overall survival. These results support the distinctive features of the category ‘AML‐MRC’ even in children.  相似文献   
122.
Clinical Oral Investigations - The biocompatible 2-methacryloyloxyethyl phosphorylcholine (MPC)-polymers, which mimic a biomembrane, reduce protein adsorption and bacterial adhesion and inhibit...  相似文献   
123.
Infected hepatic cysts are very rare compared to simple liver cysts and abscesses. We treated a 77-year-old man with an infected hepatic cyst in the lateral segment caused by Edwardsiella tarda, which has not been previously reported as a pathogenic organism associated with infected hepatic cysts. Percutaneous drainage was temporarily effective, but infection recurred after the drainage tube was removed. We then inserted two drainage tubes into the cyst using an endoscopic ultrasonography (EUS)-guided technique, which was developed from EUS-guided fine needle aspiration (EUS-FNA). The internal drainage tube was a 7 Fr double pigtail stent, and the external tube was a 6 Fr nasobiliary drainage tube. Lavage through the external drainage tube was carried out for one week. The external drainage tube was discontinued when the patient’s condition improved significantly. Sixteen days after tube insertion, he was discharged with the internal tube draining the hepatic cyst into the stomach. Fifteen months after EUS-guided drainage, CT examination showed no recurrence of the hepatic cyst. EUS-guided drainage is an effective treatment for infected hepatic cysts.  相似文献   
124.
A 77-year-old man treated with prednisolone for pemphigus developed severe sepsis by Pseudomonas aeruginosa and methicillin-resistant Staphylococcus aureus. Several antibiotics were administered. A peripheral blood smear showed growth of a large number of yeast extending pseudohyphae which could be seen both inside and outside of leucocytes. Antifungal agents were added immediately; however, he did not recover. Several days later, blood culture showed Candida albicans septicemia. The autopsy revealed microabscesses in the lung, heart, liver and kidney. A large amount of neutrophil invasion and yeast with pseudohyphae were also detected.  相似文献   
125.
126.
To dissect portal vein branches directly and encircle them separately is a common procedure that is performed to control back flow bleeding during operations for hepatocellular carcinoma with portal vein tumor thrombosis. However, this technique has an increased risk of injuring contralateral portal branches and disseminating thrombosis fragments to the remnant liver. We present an alternative technique using right-sided glissonian pedicle occlusion for hepatocellular carcinoma with left portal vein tumor thrombosis due to complex anatomical vasculatures of the hepatic pedicle. This technique would be very useful for liver resection of hepatocellular carcinoma with the major type of portal vein tumor thrombosis.  相似文献   
127.
128.
ObjectivesTo clarify whether patients with spinal muscular atrophy (SMA) or spinal and bulbar muscular atrophy (SBMA) suffer disabling muscle fatigue, and whether activity-dependent conduction block (ADCB) contributes to their fatigue. ADCB is usually caused by reduced safety factor for impulse transmission in demyelinating diseases, whereas markedly increased axonal branching associated with collateral sprouting may reduce the safety factor in chronic lower motor neuron disorders.MethodsWe assessed the fatigue severity scale (FSS) in 22 patients with SMA/SBMA, and in 100 disease controls (multiple sclerosis, myasthenia gravis, chronic inflammatory demyelinating polyneuropathy (CIDP), and axonal neuropathy). We then performed stimulated-single fibre electromyography (s-SFEMG) in the extensor digitorum communis (EDC) muscle of 21 SMA/SBMA patients, 6 CIDP patients, and 10 normal subjects.ResultsThe FSS score was the highest in SMA/SBMA patients [4.9 ± 1.1 (mean ± SD)], with 81% of them complaining of disabling fatigue, compared with normal controls (3.5 ± 1.0), whereas patients with multiple sclerosis (4.3 ± 1.6), myasthenia gravis (4.0 ± 1.6) or CIDP (4.3 ± 1.4) also showed higher FSS score. When 2000 stimuli were delivered at 20 Hz in s-SFEMG, conduction block of single motor axons developed in 46% of patients with SMA/SBMA, and 40% of CIDP patients, but in none of the normal controls.ConclusionSMA/SBMA patients frequently suffer from disabling fatigue presumably caused by ADCB induced by voluntary activity.SignificanceADCB could be the mechanism for muscle fatigue in chronic lower motor neuron diseases.  相似文献   
129.
ObjectiveTo elucidate the features of sensory nerve involvement in Fisher syndrome (FS), this study extensively investigated sensory electrophysiology.MethodsIn 47 consecutive FS patients, results of sensory nerve conduction studies in the median, ulnar and sural nerves, soleus H-reflexes, and median or tibial somatosensory-evoked potentials (SEP) were reviewed. Because of the large effects of age on amplitude of sensory nerve action potentials (SNAP), we strictly defined reduction of SNAP amplitudes by using a nomogram which age and amplitude obtained from 87normal subjects.ResultsIn routine nerve conduction studies, SNAP amplitude was reduced only in 32% of the patients, and conduction velocity was decreased in 2%. In contrast, soleus H-reflexes were frequently absent or reduced (67%). SEPs were abnormal only in 17%.ConclusionsIn FS, absent soleus H-reflexes are the most frequent electrophysiologic abnormalities, whereas SNAPs amplitudes are rarely affected. The pattern is characterized by predominant involvement of group Ia afferents with relatively preserved cutaneous afferents without evidence suggestive of demyelination.SignificanceThe major targets of immune attack by anti-GQ1b antibodies in FS appear to be group Ia neurons in the dorsal root ganglia, and this is presumably responsible for ataxia and areflexia in FS.  相似文献   
130.
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