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   11436篇
  免费   815篇
  国内免费   86篇
耳鼻咽喉   115篇
儿科学   253篇
妇产科学   426篇
基础医学   1499篇
口腔科学   389篇
临床医学   1043篇
内科学   2496篇
皮肤病学   198篇
神经病学   919篇
特种医学   406篇
外国民族医学   3篇
外科学   1876篇
综合类   241篇
一般理论   4篇
预防医学   591篇
眼科学   113篇
药学   594篇
  1篇
中国医学   47篇
肿瘤学   1123篇
  2023年   69篇
  2022年   44篇
  2021年   303篇
  2020年   185篇
  2019年   254篇
  2018年   317篇
  2017年   219篇
  2016年   264篇
  2015年   300篇
  2014年   384篇
  2013年   489篇
  2012年   816篇
  2011年   796篇
  2010年   438篇
  2009年   378篇
  2008年   652篇
  2007年   715篇
  2006年   595篇
  2005年   611篇
  2004年   596篇
  2003年   512篇
  2002年   511篇
  2001年   343篇
  2000年   337篇
  1999年   333篇
  1998年   96篇
  1997年   104篇
  1996年   66篇
  1995年   65篇
  1994年   77篇
  1993年   61篇
  1992年   163篇
  1991年   153篇
  1990年   123篇
  1989年   143篇
  1988年   76篇
  1987年   118篇
  1986年   80篇
  1985年   55篇
  1984年   67篇
  1983年   42篇
  1982年   26篇
  1981年   30篇
  1980年   26篇
  1979年   46篇
  1976年   30篇
  1975年   22篇
  1974年   29篇
  1972年   25篇
  1971年   21篇
排序方式: 共有10000条查询结果,搜索用时 17 毫秒
1.
BackgroundThe American Radium Society (ARS) Appropriate Use Criteria brain malignancies panel systematically reviewed (PRISMA [Preferred Reporting Items for Systematic Reviews and Meta-Analyses]) published literature on neurocognitive outcomes after stereotactic radiosurgery (SRS) for patients with multiple brain metastases (BM) to generate consensus guidelines.MethodsThe panel developed 4 key questions (KQs) to guide systematic review. From 11 614 original articles, 12 were selected. The panel developed model cases addressing KQs and potentially controversial scenarios not addressed in the systematic review (which might inform future ARS projects). Based upon quality of evidence, the panel confidentially voted on treatment options using a 9-point scale of appropriateness.ResultsThe panel agreed that SRS alone is usually appropriate for those with good performance status and 2–10 asymptomatic BM, and usually not appropriate for >20 BM. For 11–15 and 16–20 BM there was (between 2 case variants) agreement that SRS alone may be appropriate or disagreement on the appropriateness of SRS alone. There was no scenario (among 6 case variants) in which conventional whole-brain radiotherapy (WBRT) was considered usually appropriate by most panelists. There were several areas of disagreement, including: hippocampal sparing WBRT for 2–4 asymptomatic BM; WBRT for resected BM amenable to SRS; fractionated versus single-fraction SRS for resected BM, larger targets, and/or brainstem metastases; optimal treatment (WBRT, hippocampal sparing WBRT, SRS alone to all or select lesions) for patients with progressive extracranial disease, poor performance status, and no systemic options.ConclusionsFor patients with 2–10 BM, SRS alone is an appropriate treatment option for well-selected patients with good performance status. Future study is needed for those scenarios in which there was disagreement among panelists.  相似文献   
2.
Journal of Neuro-Oncology - Cognitive impairment is frequent in patients with high-grade glioma and requires cognitive follow-up. Cognitive screening tools such as the Montreal Cognitive Assessment...  相似文献   
3.
Aim: Migraine is neurological disorder with a complex pathophysiology. We described the neuropsychological profile of 100 migraineurs (50 with visual aura and 50 without aura), in interictal phase, compared to 50 matched healthy controls.

Materials and methods: A battery of standardized neuropsychological tests was used to assess attention, memory and executive functions. Beck Depression Inventory and Hamilton Rating Scale for Anxiety were used to evaluate anxiety and depressive symptoms. Severity of disability during daily activities was assessed by Migraine Disability Assessment.

Results: Migraine without aura showed a significant difference in comparison to healthy controls in semantic verbal fluency (p?=?0.02), delayed memory (p?<?0.001) and set-shifting (p?<?0.001). Migraine with aura showed a significant difference in delayed memory (p?=?0.001) and set-shifting (p?=?0.005) if compared to healthy controls. No significant correlation between cognitive functions and mood was found (HAM-A p?=?0.67) (BDI-II p?=?0.42).

Conclusions: Our data showed isolate and specific cognitive deficit during interictal phase in migraine patients. Future studies are need to identify if specific migraine characteristics may affect cognitive functions.  相似文献   

4.
5.

Background

In colorectal cancer liver metastases (CRCLM), bevacizumab-based neoadjuvant strategies provide increased pathologic response. We aimed at assessing the activity of perioperative capecitabine, oxaliplatin, irinotecan, and bevacizumab (COI-B regimen) in patients with potentially resectable CRCLM, and investigating biomarkers for early prediction of pathologic response.

Patients and Methods

This was a single-center phase II study enrolling patients with liver-limited, borderline resectable disease and/or high-risk features. Patients received 5 preoperative and 4 postoperative cycles of biweekly COI-B (irinotecan 180 mg/m2 and bevacizumab 5 mg/Kg on day 1, oxaliplatin 85 mg/m2 on day 2, and capecitabine 1000 mg/m2 twice a day on days 2 to 6). The primary endpoint was pathologic response rate in the intention-to-treat population. A Simon 2-stage design was adopted to detect an increase from 30% to 50% with a power of 90%. Dynamic imaging biomarkers (early tumor shrinkage [ETS], deepness of response, maximum standardized uptake volume [SUVmax]/regression index) and next generation sequencing data were explored as surrogates.

Results

From June 2013 to March 2017, 46 patients were enrolled. Pathologic response was achieved in 63% patients (endpoint met), and responders achieved significantly better survival outcomes with respect to non-responders. The most frequent grade 3/4 adverse events were diarrhea and neutropenia (8.7%) in the preoperative phase and thromboembolic events (5.9%) in the postoperative phase. ETS and lower SUV-2 were significantly associated with pathologic response.

Conclusion

The COI-B regimen is a feasible and highly active perioperative strategy in patients with molecularly unselected, potentially resectable CRCLM. ETS and SUV-2 have a promising role as imaging-based biomarkers for pathologic response.  相似文献   
6.
7.
8.
9.
Silk fibroin (SF) obtained from Bombyx mori cocoon is a very promising biopolymer. It can be processed from aqueous solutions to obtain many versatile scaffolds useful in optoelectronics, photonics, and biomedicine. Aqueous solutions are prepared by dissolving degummed fibroin with chaotropic agents and then purifying by dialysis. This work presents, for the first time, a solubilization protocol, involving CeCl3·7H2O as chaotropic salt in water and ethanol, that allows to regenerate SF under a fibrous form, unlike the standard Ajisawa’s method, which uses CaCl2 and allows to obtain aqueous gels. All the experimental analyses performed (SEM, XPS, WAXS, ATR‐FTIR, NMR) suggest that the fiber recovered preserves most of the morphological and structural features of the pristine SF and is doped with Ce(III) ions, that interact mainly with the oxygen atoms of C?O moieties and side‐chains of amino acids. Ce(III) doped SF could be the base for new luminescent materials.  相似文献   
10.
La radiologia medica - To evaluate the accuracy of preoperative contrast-enhanced magnetic resonance imaging (MRI) in the assessment of radiological depth of invasion (rDOI) and bone invasion in...  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