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   1550篇
  免费   161篇
  国内免费   35篇
耳鼻咽喉   2篇
儿科学   113篇
妇产科学   29篇
基础医学   483篇
口腔科学   29篇
临床医学   174篇
内科学   236篇
皮肤病学   117篇
神经病学   147篇
特种医学   35篇
外科学   93篇
综合类   102篇
现状与发展   2篇
预防医学   76篇
眼科学   11篇
药学   24篇
中国医学   6篇
肿瘤学   67篇
  2024年   3篇
  2023年   32篇
  2022年   43篇
  2021年   49篇
  2020年   69篇
  2019年   72篇
  2018年   64篇
  2017年   74篇
  2016年   62篇
  2015年   63篇
  2014年   81篇
  2013年   95篇
  2012年   66篇
  2011年   86篇
  2010年   74篇
  2009年   85篇
  2008年   80篇
  2007年   72篇
  2006年   71篇
  2005年   59篇
  2004年   42篇
  2003年   39篇
  2002年   38篇
  2001年   30篇
  2000年   23篇
  1999年   31篇
  1998年   37篇
  1997年   12篇
  1996年   27篇
  1995年   15篇
  1994年   22篇
  1993年   14篇
  1992年   19篇
  1991年   9篇
  1990年   9篇
  1989年   3篇
  1988年   5篇
  1987年   4篇
  1986年   6篇
  1985年   3篇
  1984年   9篇
  1983年   4篇
  1982年   10篇
  1980年   5篇
  1979年   5篇
  1978年   6篇
  1977年   8篇
  1976年   3篇
  1970年   2篇
  1969年   2篇
排序方式: 共有1746条查询结果,搜索用时 31 毫秒
1.
2.
目的分析一腓骨肌萎缩症家系的临床表现及不同基因检测方法的特点。方法收集一CMT家系8名成员临床资料,并应用等位基因特异性PCR-双酶切方法及多重连接依赖的探针扩增技术(MLPA)检测PMP22基因突变情况,同时选择60名性别、年龄无明显差异的健康人做为对照组。结果该家系中患病者以行走不稳、跨阈步态,伴有弓形足为主要临床表现。该家系中5名成员经等位基因特异性PCR-双酶切及MLPA方法均检测出PMP22基因重复序列,其中出现临床症状的有4名(Ⅱ3、Ⅱ9、Ⅱ11、Ⅲ7),未出现临床症状但基因检测结果示PMP22基因重复序列的为携带者有1名(Ⅲ5),家系中余3名成员及对照组60名均未见重复序列。结论基因检测在明确CMT诊断中起重要作用,且MLPA法筛查基因时操作更简便、灵敏度更高、特异性更好。  相似文献   
3.
Aplastic anaemia is both frequent and difficult to manage in patients with dyskeratosis congenita (DC). We recently treated a 23-year-old male for a year with granulocyte colony-stimulating factor (G-CSF) and erythropoietin (Ep), with an excellent neutrophil response, and a transient effect on haemoglobin levels. G-CSF alone or combined with other cytokines may provide at least a partial effect in pancytopenic patients with DC.  相似文献   
4.
Congenital muscular dystrophy (CMD) comprises a heterogeneous group of muscle disorders. We report on two stillborn sibs with early lethal CMD and a prematurely born boy who died within minutes after birth. The pregnancies were complicated by polyhydramnios. All presented with arthrogryposis multiplex congenita, severe muscle wasting, lung hypoplasia, and hydrops. The muscle biopsies showed fibrosis, variation in fiber size, and extensive fat replacement compatible with muscular dystrophy. Fatal CMD seems to be distinct from CMD with survival after birth and is probably autosomal recessively inherited.  相似文献   
5.
应用对应于Dystrophin基因缺失热区的二对PCR引物和一对内对照无关引物,在同一反应体系中扩增,检测66例DMD/BMD患者。发现其中25例存在17号或49号外显子缺失,与同时采用cDNA探针杂交检测出的35例基因缺失相比.检出率达71.4%。说明该扩增系统能够作为快速筛查缺失型DMD/BMD患者的有效手段。这对指导合理选用探针,尤其在产前诊断方面,具有重要意义。  相似文献   
6.
Introduction – Arthrogryposis multiplex congenita (AMC) may be associated with multiple developmental defects. In some severely affected newborns with AMC, autopsy studies have suggested a common mechanism of malmigration at the spinal and cerebral levels. To our knowledge, a constellation of arthrogryposis, epileptic seizures, and brain migrational anomalies in adult patients has not previously been described in a clinical material. Material and methods – Six consecutive adult patients with arthrogryposis multiplex congenita and epileptic seizures form the basis of the present study. Five patients had joint contractures and reduced muscle volume restricted to the lower extremities, whereas one patient had predominantly upper extremity affection. They were studied with magnetic resonance imaging (MRI), EEG, EMG, a neuropsychological test battery, and chromosome analysis. Results – Four of them had clear evidence of migrational brain disorders, demonstrated by MRI, in three of them roughly corresponding to the focal epileptiform EEG activity. Five of the patients had partial seizures, whereas one only had generalized tonic-clonic seizures. The MRI findings included polymicrogyria, pachygyria, and fused schizencephaly. Four had neurogenic EMG changes, one had myopathic EMG features, and one had an unremarkable EMG pattern in affected muscles. All patients witL demonstrable migrational disorders showed abnormal neuropsychological features. Three patients were mentally retarded. A chromosome abnormality in the form of a ring chromosome 18 was present in one patient. Conclusion – We suggest that AMC, epileptic seizures, and migrational brain disorders may form the integral parts of a hitherto undescribed syndrome in adults. A wide-spread defect in neuronal migration along the entire neural axis may be the underlying mechanism of the cerebral and the peripheral symptoms.  相似文献   
7.
Localised agenesis of the scalp is the most frequent patern in aplasia cutis congenita (ACC), a congenital absence of the skin and occasionally of deeper layers. Several clinical groups are characterised by the location and pattern of skin defects, associated malformations and the mode of inheritance. Death occurs in 20% of cases, secondary to the associated anomalies, to infections or to haemorrhage from ulceration of the sagittal sinus when there is also a defect of the underlying skull. In this latter case, we close the defect by two rotational scalp flaps (Orticochea technique) at birth. A three-dimensional CT study is useful for showing the extent of the skull defect and the deformity of the craniofacial complex and the changes in the bone after treatment.  相似文献   
8.
A 3.5 year old male patient with dyskeratosis congenita (DC) presented at the age of 13 months with isolated neutropenia preceding characteristic skin findings. The average absolute neutrophil count of 500/mm3 persisted without the presence of anemia or thrombocytopenia during the follow up. Neutropenia responded to granulocyte-colony stimulating factor (G-CSF) at a dose of 10 μg/kg per day. Immunologic findings were normal as was the chromosomal stability and sister chromatid exchange.  相似文献   
9.
检测25例脑肿瘤中抑制癌基因P53突变情况。突用复合PCR,聚合酶链反应-=单链构象多态性分析法,统计学处理采用X^2检验。结果:P53基因总的突变率为44.0%,其中第5外显子突变率为28.0%,第6外显子突变率12.0%,第7外显子突变率为12.0%,第8外显子突变率16.0%;病理分级Ⅱ级及其以上突变为72.7%,  相似文献   
10.
We present an atypical case of peripheral nervous system (PNS) involvement in Sjogren's syndrome in a 63 year-old woman. Symptoms of an entrapment neuropathy were the first manifestation of the systemic disease and they were subsequently coupled to those of a mononeuritis multiplex. Clinical and laboratory signs for the diagnosis of Sjogren's syndrome became subsequently overt. The mononeuritis multiplex remained clinically limited to the upper limbs and characterized by unusually severe motor symptoms which progressed up to the development of a final complete deplegia. By contrast, sensory symptoms at the upper limbs remained mild over the entire course of the disease and the lower limbs revealed a subclinical sensory-motor damage only during the late stage.  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