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   285篇
  免费   15篇
  国内免费   5篇
耳鼻咽喉   6篇
儿科学   13篇
妇产科学   5篇
基础医学   62篇
口腔科学   10篇
临床医学   39篇
内科学   36篇
皮肤病学   12篇
神经病学   4篇
特种医学   18篇
外科学   27篇
综合类   30篇
预防医学   13篇
眼科学   3篇
药学   12篇
中国医学   6篇
肿瘤学   9篇
  2021年   8篇
  2020年   5篇
  2018年   3篇
  2017年   3篇
  2016年   3篇
  2015年   6篇
  2014年   10篇
  2013年   10篇
  2012年   7篇
  2011年   3篇
  2010年   11篇
  2009年   8篇
  2008年   9篇
  2007年   12篇
  2006年   12篇
  2005年   10篇
  2004年   9篇
  2003年   10篇
  2002年   7篇
  2001年   7篇
  2000年   9篇
  1999年   4篇
  1998年   7篇
  1997年   10篇
  1996年   13篇
  1995年   7篇
  1994年   3篇
  1993年   4篇
  1992年   3篇
  1991年   7篇
  1990年   4篇
  1989年   5篇
  1988年   8篇
  1986年   2篇
  1985年   9篇
  1984年   7篇
  1983年   3篇
  1982年   7篇
  1981年   2篇
  1980年   2篇
  1978年   5篇
  1977年   3篇
  1976年   7篇
  1975年   6篇
  1973年   3篇
  1967年   3篇
  1965年   1篇
  1959年   1篇
  1954年   1篇
  1936年   1篇
排序方式: 共有305条查询结果,搜索用时 15 毫秒
61.
A new modification of the method for cultivation of cells from blood vessel explants has been proposed, and on its basis several cell lines from different vessels of human embryo and adult subjects have been derived. The sensitivity of vessel cells to viruses was studied on a model of aorta cell culture using a wide spectrum of RNA and DNA viruses. All the strains under study with the exception of respiratory-syncytial virus (RSV) and encephalomyocarditis (EMC) virus induced a productive infection in the cells. The infection with RSV and EMC was abortive. The possibility of virus replication in vessel cells was confirmed by isolation of adenovirus from a human renal artery biopsy.  相似文献   
62.
The paper describes a holiday for a group of adolescents with cancer (from the Young Oncology Unit at the Christie Hospital, Manchester, UK) at Malcolm Sargent House, Prestwick, Scotland. The aim was to provide an opportunity for young people with cancer to build and to develop therapeutic relationships away from the pressures of hospital, home and treatment. The nature and range of care given by the nurses and social worker who accompanied them is described and includes accounts of individual progress which are demonstrated by brief case studies.  相似文献   
63.
Albino Wistar rats (Rattus norvegius) fed semi-purified diets containing 3.5%, 8%, 27%, and 64% casein, respectively, as the protein source, were poisoned with an intraperitoneal dose of 20mg N-nitrosodimethylamine (NDMA)/kg, following cannulation of the bile duct, in vitro, under urethane anaesthesia. Bile exudates was collected at designated time intervals and analysed for unchanged NDMA using thin layer chromatography and gas liquid chromatography methods. Rats on 64% high protein diet (HPD) were the highest excretors of NDMA, followed by rats on the 3.5% kwashiorkorigenic diet (KWD), 8% low protein diet (LPD) and 27% normal protein diet (NDP) as the least excretors, in that order. The corresponding values for culmulative excretions of NDMA were 4.38%, 2.74%, 2.96% and 4.11%, and for elimination rate contents they were 54.05Kh−1, 23.01Kh−1, 23.76Kh−1 and 48.88Kh−1, while the respective elimination half-life values were 0.013h, 0.031h, 0.029h and 0.014h. The toxicological and pharmacological implication of the pharmacokinetic findings are discussed.  相似文献   
64.
Increased trinucleotide repeat instability with advanced maternal age   总被引:15,自引:14,他引:1  
Nucleotide repeat instability is associated with an increasing number of cancers and neurological disorders. The mechanisms that govern repeat instability in these biological disorders are not well understood. To examine genetic aspects of repeat instability we have introduced an expanded CAG trinucleotide repeat into transgenic mice. We have detected intergenerational CAG repeat instability in transgenic mice only when the transgene was maternally transmitted. These intergenerational instabilities increased in frequency and magnitude as the transgenic mother aged. Furthermore, triplet repeat variations were detected in unfertilized oocytes and were comparable with those in the offspring. These data show that maternal repeat instability in the transgenic mice occurs after meiotic DNA replication and prior to oocyte fertilization. Thus, these findings demonstrate that advanced maternal age is an important factor for instability of nucleotide repeats in mammalian DNA.   相似文献   
65.
BACKGROUND: Erosive lichen planus is a severe, recurrent and recalcitrant disease that affects several mucosal areas, mostly the genital area and the mouth, but also, for example, the oesophagus and perianal area. The disease causes serious symptoms, because of the raw, de-epithelialized mucosa and healing with scars/adhesions, which affect the patient's life in many ways. It causes, for example, difficulties in eating, drinking and going to the bathroom. Treatment is complicated and, so far, few therapeutic drugs other than steroids have been reported. OBJECTIVES: As the disease has severe implications on the patient's life it is important to investigate the psychological health of the patients, as well as the influence of stress on their health and wellbeing, in order to improve treatment. STUDY DESIGN, SUBJECTS AND METHODS: Forty-nine consecutive patients with erosive lichen planus were included during a 1-year period. The study was carried out as 'state-of-the-last-month', and stress, state anxiety, depression and 'erosive lichen planus factors', i.e. symptoms affecting daily life, were assessed. RESULTS: Eighty-seven per cent of the patients had symptoms, severely affecting daily life. Unexpectedly, oral symptoms seemed to be the most prominent. Our results showed that depression, anxiety and stress were more common in patients with erosive lichen planus than in a control group. DISCUSSION AND CONCLUSIONS: Erosive lichen planus is a severe disease with symptoms and complications affecting the patient's life. Our results indicate that their psychological health is also affected and emphasize the need for close collaboration between physicians, dentists with special knowledge in oral medicine and counsellors/psychologists to optimize handling of these patients.  相似文献   
66.
Oestrogen has been proposed to influence platelet activity and formation of the vasoactive eicosanoids thromboxane and prostacyclin. Previous studies have been based on ex vivo techniques with well-known artifacts during blood sampling and ex vivo conditions. The present study is the first to assess in vivo formation through gas chromatographic/mass spectrometric analysis of the major urinary metabolites 2,3-dinor-thromboxane B2 and 2,3-dinor-6-keto-PGF. Ten consecutive male patients with prostatic carcinoma participating in a randomized study comparing the effects of parenteral oestrogen therapy ( n =5) with orchidectomy ( n =5) were included. Oestrogen was given as polyestradiol phosphate 240 mg i.m. every month. 2,3-dinor thromboxane B2 and 2,3-dinor-6-keto-PGF were analysed with the help of tetradeuterated internal carriers/standards. We found a consistent decrease of in vivo formation of thromboxane by ≈40% during parenteral oestrogen therapy ( P =0.008) and a doubling after surgical castration. The ratio of prostacyclin to thromboxane increased by ≈50% ( P =0.023) during oestrogen therapy. In conclusion, oestrogen induced a marked decrease of in vivo formation of thromboxane and a marked increase in the ratio of prostacyclin to thromboxane formation in all patients. According to current knowledge this should be beneficial for the cardiovascular system. Furthermore, thromboxane formation increased after surgical castration. The latter fact should direct attention to the influence of androgens on thromboxane synthesis. Our findings discloses a marked sex-hormone sensitivity of the thromboxane-forming system.  相似文献   
67.
Registry data on invasive cervical cancers (n = 1,274) from four major hospitals (1984‐2012) were analysed to determine their value for informing local service delivery in Australia. The methodology comprised disease‐specific survival analyses using Kaplan‐Meier product‐limit estimates and Cox proportional hazards models and treatment analyses using logistic regression. Five‐ and 10‐year survivals were 72% and 68%, respectively, equating with relative survival estimates for Australia and the USA. Most common treatments were surgery and radiotherapy. Systemic therapies increased in recent years, generally with radiotherapy, but were less common for residents from less accessible areas. Surgery was more common for younger women and early‐stage disease, and radiotherapy for older women and regional and more advanced disease. The proportion of glandular cancers increased in‐step with national trends. Little evidence of variation in risk‐adjusted survival presented over time or by Local Health District. The study illustrates the value of local registry data for describing local treatment and outcomes. They show the lower use of systemic therapies among residents of less accessible areas which warrants further investigation. Risk‐adjusted treatment and outcomes did not vary by socio‐economic status, suggesting equity in service delivery. These data are important for local evaluation and were not available from other sources.  相似文献   
68.
Congenital chylothorax in siblings   总被引:1,自引:0,他引:1  
We describe two cases of congenital chylothorax in siblings with important differences from previously described familial cases. Our findings support the likelihood of an autosomal recessive inheritance in some cases of this condition, rather than X-linked recessive inheritance, which has also been suggested. Autopsy findings from one of these cases and others previously described suggest that the pathophysiological mechanisms involved may be variable.  相似文献   
69.
目的观察高位胸段硬膜外阻滞(TEA)对顽固性心绞痛(FAP)的治疗效果及循环内皮细胞(CEC)数量。方法20例FAP患者接受TEA治疗,观察疗效和心电图变化,并于TEA治疗前及治疗结束时检测血浆CEC的变化。结果TEA治疗后心绞痛缓解率100%,心电图ST段压低导联数和ST压低值显著减少(P<0.05),CEC显著减少(P<0.01)。结论TEA治疗FAP疗效满意,并可能通过保护血管内皮细胞起作用。  相似文献   
70.
广州管圆线虫病的临床预后   总被引:6,自引:0,他引:6  
目的 :探讨 1997年 10~ 11月间 ,温州市区暴发的广州管圆线虫病的临床预后。方法 :入选病例符合如下条件 :(1)于 1997年 9月中旬~ 11月中旬期间急性起病 ;(2 )头痛和 (或 )游移性躯干四肢皮肤抚摸痛 ;(3)周围血液或脑脊液中嗜酸性粒细胞增高和 (或 )广州管圆线虫虫体抗原抗体阳性 (EL ISA法 ) ;(4)病前一个月内有食用未熟的淡水螺肉或贝虾史 ;(5 )排除其它蠕虫移行症。采用统一设计的随访调查表 ,由专人对符合上述标准的 35例 ,通过电话和(或 )面访 ,进行为期 1.5年的随访。结果 :全组无死亡 ,无复发 ,无严重残疾或并发症 ,遗留症状轻微 ,以局限性的主观或客观根性感觉障碍为主。主观症状多于客观体征。早期神经根痛严重者 ,后遗根性感觉异常较多。结论 :该组病例远期预后良好 ,病程自限。病性较重者多数可遗留轻微局限性感觉异常或感觉减退 ,可能与广州管圆线虫蚴对脊髓后根神经髓鞘直接或间接损害以及虫体死亡后致局部肉芽肿形成有关  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