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   1053508篇
  免费   80998篇
  国内免费   2776篇
耳鼻咽喉   13762篇
儿科学   35792篇
妇产科学   29287篇
基础医学   152746篇
口腔科学   28646篇
临床医学   96541篇
内科学   205480篇
皮肤病学   23605篇
神经病学   84845篇
特种医学   40361篇
外国民族医学   309篇
外科学   159761篇
综合类   24279篇
一般理论   428篇
预防医学   81878篇
眼科学   23748篇
药学   75969篇
  3篇
中国医学   2092篇
肿瘤学   57750篇
  2021年   8618篇
  2019年   8901篇
  2018年   12499篇
  2017年   9616篇
  2016年   10849篇
  2015年   12285篇
  2014年   16809篇
  2013年   25067篇
  2012年   33680篇
  2011年   35713篇
  2010年   21093篇
  2009年   19877篇
  2008年   32699篇
  2007年   34502篇
  2006年   34798篇
  2005年   33302篇
  2004年   32184篇
  2003年   30893篇
  2002年   29616篇
  2001年   47342篇
  2000年   48361篇
  1999年   40647篇
  1998年   11745篇
  1997年   10561篇
  1996年   10515篇
  1995年   10081篇
  1994年   9365篇
  1993年   8741篇
  1992年   32458篇
  1991年   31641篇
  1990年   31148篇
  1989年   29999篇
  1988年   27291篇
  1987年   27439篇
  1986年   25537篇
  1985年   24692篇
  1984年   18517篇
  1983年   15614篇
  1982年   9395篇
  1979年   16923篇
  1978年   12274篇
  1977年   10376篇
  1976年   9798篇
  1975年   10204篇
  1974年   12349篇
  1973年   11875篇
  1972年   10906篇
  1971年   10130篇
  1970年   9393篇
  1969年   8737篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
82.

Cerebellar mutism syndrome (CMS) occurs in one out of four children after posterior fossa tumor surgery, with open questions regarding risk factors, pathophysiology, and prevention strategies. Because of similarities between several cerebellar syndromes, a common pathophysiology with damage to the dentato-thalamo-cortical and dentato-rubro-olivary pathways has been proposed. Hypertrophic olivary degeneration (HOD) is an imaging correlate of cerebellar injury observed for instance in stroke patients. Aim of this study was to investigate whether the occurrence and severity of CMS correlates with the extent of damage to the relevant anatomical structures and whether HOD is a time-dependent postoperative neuroimaging correlate of CMS. We performed a retrospective single center study of CMS patients compared with matched non-CMS controls. CMS occurred in 10 children (13% of the overall cohort) with a median age of 8 years. Dentate nucleus (DN) injury significantly correlated with CMS, and superior cerebellar peduncle (SCP) injury was associated by tendency. HOD was observed as a dynamic neuroimaging phenomenon in the postoperative course and its presence significantly correlated with CMS and DN injury. Children who later developed HOD had an earlier onset and tended to have longer persistence of CMS. These findings can guide surgical measures to protect the DN and SCP during posterior fossa tumor resections and to avoid a high damage burden (i.e., bilateral damage). Development of intraoperative neuromonitoring of the cerebellar efferent pathways as well as improved preoperative risk stratification could help to establish a patient-specific strategy with optimal balance between degree of resection and functional integrity.

  相似文献   
83.
84.
85.
IntroductionInterprofessional learning (IPL) is a vital aspect of training in radiation oncology professions, yet is rarely delivered to those professionals who work most closely together in clinical practice. Scenario-based learning using simulation facilities provides a unique opportunity to facilitate this learning and this project aimed to determine the impact and value of this initiative.MethodsSmall groups comprising post-graduate diploma pre-registration therapeutic radiographers, medical physics trainees and radiation oncology registrars were challenged with 4 plausible and challenging radiotherapy scenarios within an academic simulation centre. Pre- and post-event completion of the “Readiness for Interprofessional Learning Scale” measured impact and a Likert-style survey gathered feedback from participants.ResultsThe session increased participants' teamwork and collaboration skills as well as strengthening professional identities. Participants reported high levels of enjoyment related to collaborative working, communication and observing other professionals deploying their technical skills and specialist knowledge.ConclusionAlthough beneficial, simulated scenarios offering equal opportunities for engagement across the professions are challenging to plan and timetabling issues between the 3 groups present significant difficulties. The safe environment and unique opportunity for these groups to learn together was particularly well received and future oncology-specific simulated scenario sessions are planned with larger cohorts.Implications for practiceSimulated scenario training can be used to improve team working across the radiotherapy interprofessional team and may have wider use in other specialist interdisciplinary team development.  相似文献   
86.
Respiratory cysts are benign lesions lined by normal respiratory epithelium. There are few reported cases localized to the orbit, while those of the eyelid are exceedingly rare. Respiratory cysts usually arise either from a non‐hereditary congenital malformation, where they are distinguished as choristomatous, or from trauma. Here, we report a case of a 53‐year‐old man who presented with a large right lower eyelid cyst that was histopathologically diagnosed as a respiratory cyst.  相似文献   
87.
A local pedicled vascularized bone flap can prevent the morbidity and cost of free bone flap surgery in small segmental bone defects or long cartilaginous defects of the head and neck. Such flaps can also be useful in patients who are high risk for surgery. The periosteal vascularity of the mandible can be used to design islanded facial artery-based bone flaps, which can be utilized to that extent. Two patients with a small segmental mandibulectomy defect and one patient with a long cricotracheal resection defect underwent reconstruction using three different designs of islanded facial artery osteomyomucosal/osseous flap (iFOMM). The patients had a minimum follow-up period of 18 months. All flaps were successful, with satisfactory healing and without any functional deficit or disease at last follow-up.  相似文献   
88.
89.

Background

Early dumping is a poorly defined and incompletely understood complication after Roux-en-Y gastric (RYGB).

Objective

We performed a mixed-meal tolerance test in patients after RYGB to address the prevalence of early dumping and to gain further insight into its pathophysiology.

Setting

The study was conducted in a regional hospital in the northern part of the Netherlands.

Methods

From a random sample of patients who underwent primary RYGB between 2008 and 2011, 46 patients completed the mixed-meal tolerance test. The dumping severity score for early dumping was assessed every 30 minutes. A sum score at 30 or 60 minutes of ≥5 and an incremental score of ≥3 points were defined as indicating a high suspicion of early dumping. Blood samples were collected at baseline, every 10 minutes during the first half hour, and at 60 minutes after the start.

Results

The prevalence of a high suspicion of early dumping was 26%. No differences were seen for absolute hematocrit value, inactive glucagon-like peptide-1, and vasoactive intestinal peptide between patients with or without early dumping. Patients at high suspicion of early dumping had higher levels of active glucagon-like peptide-1 and peptide YY.

Conclusion

The prevalence of complaints at high suspicion of early dumping in a random population of patients after RYGB is 26% in response to a mixed-meal tolerance test. Postprandial increases in both glucagon-like peptide-1 and peptide YY are associated with symptoms of early dumping, suggesting gut L-cell overactivity in this syndrome.  相似文献   
90.
Ovarian carcinoma is one of the most lethal malignancies, but only very few prognostic biomarkers are known. The degradome, comprising proteases, protease non-proteolytic homologues and inhibitors, have been involved in the prognosis of many cancer types, including ovarian carcinoma. The prognostic significance of the whole degradome family has not been specifically studied in high-grade serous ovarian cancer. A targeted DNA microarray known as the CLIP-CHIP microarray was used to identify potential prognostic factors in ten high-grade serous ovarian cancer women who had early recurrence (<1.6 years) or late/no recurrence after first line surgery and chemotherapy. In women with early recurrence, we identified seven upregulated genes (TMPRSS4, MASP1/3, SPC18, PSMB1, IGFBP2, CFI – encoding Complement Factor I – and MMP9) and one down-regulated gene (ADAM-10). Using immunohistochemistry, we evaluated the prognostic effect of these 8 candidate genes in an independent cohort of 112 high-grade serous ovarian cancer women. Outcomes were progression, defined according to CA-125 criteria, and death. Multivariate Cox proportional hazard regression models were done to estimate the associations between each protein and each outcome. High ADAM-10 expression (intensity of 2–3) was associated with a lower risk of progression (adjusted hazard ratio (HR): 0.51; 95% confidence interval (CI): 0.29-0.87). High complement factor I expression (intensity 2–3) was associated with a higher risk of progression (adjusted HR: 2.30, 95% CI: 1.17–4.53) and death (adjusted HR: 3.42; 95% CI: 1.72–6.79). Overall, we identified the prognostic value of two proteases, ADAM-10 and complement factor I, for high-grade serous ovarian cancer which could have clinical significance.  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