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   234篇
  免费   11篇
耳鼻咽喉   3篇
儿科学   15篇
妇产科学   2篇
基础医学   27篇
口腔科学   8篇
临床医学   19篇
内科学   50篇
皮肤病学   6篇
神经病学   6篇
特种医学   47篇
外科学   12篇
综合类   1篇
预防医学   30篇
眼科学   1篇
药学   9篇
中国医学   1篇
肿瘤学   8篇
  2021年   2篇
  2018年   2篇
  2016年   6篇
  2014年   3篇
  2013年   5篇
  2012年   3篇
  2011年   3篇
  2010年   11篇
  2009年   10篇
  2008年   4篇
  2007年   6篇
  2006年   8篇
  2005年   8篇
  2004年   7篇
  2003年   6篇
  2002年   3篇
  2001年   5篇
  2000年   2篇
  1999年   2篇
  1998年   12篇
  1997年   15篇
  1996年   7篇
  1995年   4篇
  1994年   8篇
  1993年   3篇
  1992年   3篇
  1991年   3篇
  1989年   8篇
  1988年   7篇
  1987年   11篇
  1986年   6篇
  1985年   11篇
  1984年   2篇
  1983年   4篇
  1982年   3篇
  1980年   4篇
  1978年   1篇
  1977年   2篇
  1976年   4篇
  1975年   7篇
  1974年   2篇
  1973年   2篇
  1972年   2篇
  1966年   1篇
  1960年   1篇
  1958年   2篇
  1955年   4篇
  1954年   3篇
  1952年   1篇
  1948年   1篇
排序方式: 共有245条查询结果,搜索用时 15 毫秒
41.
Laurens  RG  Jr; Pine  JR; Honig  EG 《Radiology》1983,146(2):295-297
Primary cavitating lung carcinomas have not previously been described with spontaneous pneumothorax as the presenting manifestation. Two patients whose pneumothoraces resulted in the initial diagnosis of a primary cavitary lung carcinoma are described. Pathologic evidence of vascular invasion suggests tumor necrosis with secondary rupture into the pleural space as a likely mechanism for pneumothorax.  相似文献   
42.
43.
The potential of localized heating as a adjunct to radiation therapy   总被引:1,自引:0,他引:1  
  相似文献   
44.
Clinical and laboratory findings in a case of bullous pemphigoid developing during the course of metastatic spread of rectal adenocarcinoma are presented. In addition a transient figurate erythema occurred. The possibility of a causal relationship between bullous pemphigoid and malignant disease is discussed.  相似文献   
45.
The circulatory effects of reserpine   总被引:2,自引:0,他引:2  
McQUEEN EG  DOYLE AE  SMIRK FH 《Circulation》1955,11(2):161-169
  相似文献   
46.
47.
Innes AM, Boycott KM, Puffenberger EG, Redl D, MacDonald IM, Chudley AE, Beaulieu C, Perrier R, Gillan T, Wade A, Parboosingh JS. A founder mutation in BBS2 is responsible for Bardet‐Biedl syndrome in the Hutterite population: utility of SNP arrays in genetically heterogeneous disorders. Bardet‐Biedl syndrome (BBS) is a multisystem genetically heterogeneous disorder, the clinical features of which are largely the consequence of ciliary dysfunction. BBS is typically inherited in an autosomal recessive fashion, and mutations in at least 14 genes have been identified. Here, we report the identification of a founder mutation in the BBS2 gene as the cause for the increased incidence of this developmental disorder in the Hutterite population. To ascertain the Hutterite BBS locus, we performed a genome‐wide single nucleotide polymorphism (SNP) analysis on a single patient and his three unaffected siblings from a Hutterite family. The analysis identified two large SNP blocks that were homozygous in the patient but not in his unaffected siblings, one of these regions contained the BBS2 gene. Sequence analysis and subsequent RNA studies identified and confirmed a novel splice site mutation, c.472‐2A>G, in BBS2. This mutation was also found in homozygous form in three subsequently studied Hutterite BBS patients from two different leuts, confirming that this is a founder mutation in the Hutterite population. Further studies are required to determine the frequency of this mutation and its role, if any, in the expression of other ciliopathies in this population.  相似文献   
48.
PURPOSE: We investigate the patterns of failure in the treatment of glioblastoma(GBM) based on clinical target volume(CTV) margin size,dose delivered to the site of initial failure,and the use of temozolomide and intensity-modulated radiotherapy(IMRT).METHODS: Between August 2000 and May 2010,161 patients with GBM were treated with radiotherapy with or without concurrent temozolomide.Patients were treated with CTV expansions that ranged from 5 to 20 mm using a shrinking field technique.Patterns of failure and time to progression and overall survival were compared based on CTV margin,use of temozolomide,and use of IMRT.Kaplan Meier analysis was used to estimate survival times,and χ test was used for comparison of cohorts.RESULTS: For patients treated with 5-,10-,and 15-to 20-mm CTV,79%,77%,and 86% experienced failures in the 60 Gy volume,respectively.Forty-eight percent,55%,and 66% of patients with 5-,10-,and 15-to 20-mm CTV experienced failures in the 46 Gy volume,respectively.There was no statistical difference between patients treated with 5-,10-,15-to 20-mm margins with regard to 60 Gy failure(P=0.76),46 Gy failure(P=0.51),or marginal failure(P=0.73).Eighty percent of patients receiving temozolomide experienced failures in the 60 Gy volume.There was no increased likelihood of marginal failures in patients receiving IMRT(P =0.97).CONCLUSIONS: Modern treatment techniques including use of concurrent temozolmide,limited CTV margin size,and IMRT have not greatly changed the patterns of failure of GBM.  相似文献   
49.
IntroductionWith the emergence of the COVID-19 pandemic, all elective surgery was temporarily suspended in the UK, allowing for diversion of resource to manage the anticipated surge of critically unwell patients. Continuing to deliver time-critical surgical care is important to avoid excess morbidity and mortality from pathologies unrelated to COVID-19. We describe the implementation and short-term surgical outcomes from a system to deliver time-critical elective surgical care to patients during the COVID-19 pandemic.Materials and methodsA protocol for the prioritisation and safe delivery of time-critical surgery at a COVID-19 ‘clean’ site was implemented at the Nuffield Health Exeter Hospital, an independent sector hospital in the southwest of England. Outcomes to 30 days postoperatively were recorded, including unplanned admissions after daycase surgery, readmissions and complications, as well as the incidence of perioperative COVID-19 infection in patients and staff.ResultsA total of 128 surgical procedures were performed during a 31-day period by a range of specialties including breast, plastics, urology, gynaecology, vascular and cardiology. There was one unplanned admission and and two readmissions. Six complications were identified, and all were Clavien-Dindo grade 1 or 2. All 128 patients had preoperative COVID-19 swabs, one of which was positive and the patient had their surgery delayed. Ten patients were tested for COVID-19 postoperatively, with none testing positive.ConclusionThis study has demonstrated the implementation of a safe system for delivery of time-critical elective surgical care at a COVID-19 clean site. Other healthcare providers may benefit from implementation of similar methodology as hospitals plan to restart elective surgery.  相似文献   
50.
Inhibitory synaptogenesis in mouse somatosensory cortex   总被引:4,自引:3,他引:1  
It is widely believed that inhibitory synapses are not present or present in only small numbers in the rodent cerebral cortex during the early postnatal period when the cortex is being innervated by thalamocortical fibers. Quantitative electron microscopy was carried out on the posteromedial barrel subfield of mouse somatosensory cortex from postnatal day 4 (P4) when thalamocortical innervation of the barrels is becoming established, through to sexual maturity (>P32), and in adulthood. Both asymmetrical (putatively excitatory) and symmetrical (putatively inhibitory) synapses were present in all layers from P4. The symmetrical synapses were immunoreactive for GABA at all ages. There was a progressive increase in both asymmetrical and symmetrical synapses up to P32, density in all layers increasing 16-fold, with the production of asymmetrical synapses leading and greatly outstripping that of symmetrical. From P32 to P120, the oldest age studied, synaptic numbers declined by 18% to 13 times the P4 level, but this affected predominantly layers II/III, IV and V, and mainly involved asymmetrical synapses. The relative percentage of asymmetrical to symmetrical synapses from P4 to P8 was 57%/43% but at P32 it was 89.5%/10.5% and in adulthood 85.4%/14.6%. These data indicate that inhibitory synaptogenesis in the rodent cortex begins earlier than previously thought, a basis for inhibition being present from the earliest period. Pruning of all synapses occurs well after thalamocortical innervation is established and inhibitory synapses are less affected by the pruning process.   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