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   200篇
  免费   8篇
  国内免费   36篇
耳鼻咽喉   1篇
儿科学   9篇
基础医学   17篇
口腔科学   11篇
临床医学   27篇
内科学   39篇
皮肤病学   24篇
神经病学   10篇
特种医学   12篇
外科学   25篇
综合类   7篇
预防医学   13篇
眼科学   1篇
药学   44篇
中国医学   1篇
肿瘤学   3篇
  2022年   2篇
  2021年   4篇
  2020年   5篇
  2019年   8篇
  2018年   6篇
  2017年   1篇
  2016年   3篇
  2015年   4篇
  2014年   8篇
  2013年   12篇
  2012年   10篇
  2011年   14篇
  2010年   6篇
  2009年   6篇
  2008年   6篇
  2007年   21篇
  2006年   14篇
  2005年   16篇
  2004年   2篇
  2003年   6篇
  2002年   2篇
  2001年   4篇
  2000年   6篇
  1999年   3篇
  1998年   7篇
  1997年   3篇
  1996年   2篇
  1995年   6篇
  1994年   4篇
  1993年   6篇
  1992年   2篇
  1991年   4篇
  1990年   5篇
  1989年   4篇
  1988年   6篇
  1987年   2篇
  1986年   2篇
  1985年   2篇
  1984年   1篇
  1983年   2篇
  1981年   2篇
  1980年   4篇
  1979年   1篇
  1977年   1篇
  1974年   3篇
  1972年   1篇
  1966年   1篇
  1965年   1篇
  1954年   1篇
  1932年   1篇
排序方式: 共有244条查询结果,搜索用时 46 毫秒
1.
2.
3.
Yolk–shell nanoparticles (YSNPs) are a new class of hollow nanostructures, and their unique properties can be utilized in drug delivery systems. The recent progress in YSNPs-based carriers is highlighted in drug delivery systems. Doxorubicin hydrochloride, ceftriaxone sodium, and methotrexate are three of the most common drugs that are used in this field. According to the reported studies, the materials used most often as yolk–shells are magnetic nanoparticles and polymers. The used methods for synthesizing a diverse array of YSNPs are classified based on their core structures. Various properties of YSNPs include their high drug-loading capacity, and their ability to decrease drug toxicity and satisfactorily and efficiently release drugs.

The recent progress in yolk–shell nanoparticles (YSNPs) as a new class of hollow nanostructures applied for drug delivery.  相似文献   
4.
Objective: To identify the clinical picture of Behcet’s disease in a large cohort of patients (6500) in Iran, over a period of 35 years, and compare them with other large series from around the world. Methods: Patients with Behcet’s disease from all over Iran were seen in the Behcet’s Disease Research Unit by a multidisciplinary team (rheumatologists, dermatologists, and ophthalmologists). Diagnosis was based on ‘expert opinion’. Data were collected on a standardized data sheet (105 items), and stored in an electronic database. Data were updated at each follow‐up. Results: Male to female ratio was 1.22 : 1.00. The mean age at onset was 26 years ± 11.3. The frequency of symptoms were: oral aphthosis 97.3%, genital aphthosis 64.6%, skin manifestations 64.9% (pseudofolliculitis 54.5%, erythema nodosum 22.5%, other lesions 7%), pathergy phenomenon 52.5%, ophthalmologic manifes‐tations 56.8% (anterior uveitis 41.2%, posterior uveitis 44.9%, retinal vasculitis 32.1%), joint manifestations 37.4% (arthralgia 17.2%, monoarticular arthritis 7.6%, oligoarthritis 16.8%, ankylosing spondylitis 2%), neurological manifestations 3.8% (central manifestations 3.5%, mononeuritis multiplex 0.3%), gastrointestinal manifestations 7.4%, vascular involvement 8.3% (phlebitis 5.7%, superficial phlebitis 2.2%, large vein thrombosis 1.1%, arterial thrombosis 0.154%, aneurysm 0.5%), epididymitis 4.7%, cardiac involvement 0.6%, and pulmonary involvement 0.9%. Sedimentation rate was normal in 46.5% of patients. Abnormal urine sediment was detected in 12.2%. HLA‐B5 was present in 53.3% and HLA‐B51 in 47.9% of patients. Conclusion: Behcet’s disease is mainly seen in young people. The most frequent symptoms are mucocutaneous, ocular and joint manifestations. Comparison with large series did not show major differences.  相似文献   
5.
6.
7.
Previous serological studies documenting an association between acute lymphoblastic leukaemia (ALL) and HLA-Cw antigens suggested that the HLA-C locus might influence susceptibility to ALL. However, associations with more than one Cw antigen suggest that polymorphic variants shared by more than Cw allele could be involved. Recent studies have shown that the HLA-C locus encodes two ligands (NK1 and NK2) recognized by receptors on natural killer (NK) cells. HLA-Cw alleles encoding these ligands are dimorphic, dependent on whether they encode one or other NK ligand. To determine whether susceptibility to the common (CD10+) form of childhood ALL (c-ALL) is associated with NK1 or NK2, we carried out a molecular analysis of 94 childhood c-ALL patients and 136 infant controls. We found no difference in the frequency of NK1 and NK2 alleles, phenotypes or genotypes between the patients and controls, suggesting that this does not explain the role of the HLA-C locus in susceptibility to childhood c-ALL.  相似文献   
8.
The human T-lymphotropic virus type III (HTLV-III) is the primary cause of the acquired immunodeficiency syndrome (AIDS) and related disorders (ARC). Prior studies have reported that nearly all symptomatic patients with AIDS or ARC manifest antibody to HTLV-III. This observation has engendered efforts to screen for HTLV-III, especially prior to blood donation, with assays for antibody to HTLV-III. We report the first two cases, one with AIDS and one with ARC, that are HTLV-III virus positive but antibody negative. Accurate diagnosis of HTLV-III infection in some cases may require direct virus culture or tests for antigen. In addition, lack of HTLV-III antibody may indicate an atypical clinical course of AIDS.  相似文献   
9.
Solitary fibrous tumours are infrequent neoplasms based in the pleura that are predominantly benign with malignant pathology and behaviour described in 10–36% of cases. Extrathoracic solitary fibrous tumours (ESFTs) have been considered separately to their intrathoracic counterparts and comprise a third of all solitary fibrous tumours. The extrathoracic location was identified as an adverse prognostic factor for local recurrence but not for metastatic disease. So far, there have not been any reports of solitary fibrous tumours demonstrating caval infiltration. We present a case of a benign ESFT infiltrating into the perirenal inferior vena cava. Together with extrauterine leiomyomas, ESFTs should also be considered as a differential diagnosis for the rare benign lesions invading the inferior vena cava.  相似文献   
10.
Purpose

To gain insight into current research regarding prehospital care (PHC) in patients with potential traumatic spinal cord injury (TSCI) and to disseminate the findings to the research community.

Methods

In March 2019, we performed a literature search of publications from January 1990 to March 2019 indexed in PubMed, gray literature including professional websites; and reference sections of selected articles for other relevant literature. This review was performed according to Arksey and O’Malley’s framework.

Results

There were 42 studies selected based on the inclusion criteria for review; 18 articles regarding immobilization; 12 articles regarding movement, positioning and transport; four for spinal clearance; three for airway protection; and two for the role of PHC providers. There were some articles that covered two topics: one article was regarding movement, positioning and transport and airway protection, and two were regarding spinal clearance and the role of PHC providers.

Conclusion

There was no uniform opinion about spinal immobilization of patients with suspected TSCI. The novel lateral trauma position and one of two High Arm IN Endangered Spine (HAINES) methods are preferred methods for unconscious patients. Controlled self-extrication for patients with stable hemodynamic status is recommended. Early and proper identifying of potential TSCI by PHC providers can significantly improve patients’ outcomes and can result in avoiding unwanted spinal immobilization. Future prospective studies with a large sample size in real-life settings are needed to provide clear and evidence-based data in PHC of patients with suspected TSCI.

  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