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   13478篇
  免费   912篇
  国内免费   179篇
耳鼻咽喉   355篇
儿科学   122篇
妇产科学   251篇
基础医学   2258篇
口腔科学   286篇
临床医学   1131篇
内科学   2821篇
皮肤病学   390篇
神经病学   1087篇
特种医学   983篇
外科学   1673篇
综合类   121篇
一般理论   1篇
预防医学   479篇
眼科学   211篇
药学   1064篇
中国医学   147篇
肿瘤学   1189篇
  2023年   61篇
  2022年   227篇
  2021年   518篇
  2020年   233篇
  2019年   394篇
  2018年   462篇
  2017年   343篇
  2016年   543篇
  2015年   737篇
  2014年   885篇
  2013年   979篇
  2012年   1398篇
  2011年   1242篇
  2010年   776篇
  2009年   638篇
  2008年   846篇
  2007年   798篇
  2006年   611篇
  2005年   587篇
  2004年   450篇
  2003年   405篇
  2002年   371篇
  2001年   151篇
  2000年   152篇
  1999年   87篇
  1998年   54篇
  1997年   55篇
  1996年   47篇
  1995年   28篇
  1994年   29篇
  1993年   24篇
  1992年   37篇
  1991年   42篇
  1990年   33篇
  1989年   26篇
  1988年   27篇
  1987年   41篇
  1986年   36篇
  1985年   10篇
  1984年   18篇
  1983年   20篇
  1982年   9篇
  1981年   14篇
  1980年   10篇
  1979年   13篇
  1978年   13篇
  1974年   14篇
  1972年   15篇
  1971年   8篇
  1965年   6篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
1.
Direct peroral cholangioscopy (POC) using an ultra‐slim upper endoscope is one modality of POC for intraductal endoscopic evaluation and treatment of the bile duct. Choledochoduodenostomy (CDS) is one modality of biliary bypass surgery that provides a new route to the bile duct. We carried out direct POC using an ultra‐slim upper endoscope without the use of accessories in 10 patients (four sump syndromes, three bile duct strictures and three intrahepatic duct stones) previously undergoing surgical CDS. Direct POC was successful in all patients. The use of an intraductal balloon catheter was required in one patient for advancement of the endoscope into the bile duct. Distal bile ducts with sump syndromes were cleared using baskets and water irrigation under direct POC. Cholangiocarcinoma was diagnosed in one patient with hilar bile duct stricture after cholangioscopic evaluation and a targeting forceps biopsy under direct POC. Intrahepatic duct stones were successfully extracted after intraductal fragmentation under direct POC. Oozing bleeding occurred during intraductal lithotripsy but stopped spontaneously. Direct POC using an ultra‐slim upper endoscope without the assistance of accessories can easily be carried out in patients undergoing CDS.  相似文献   
2.
The acquisition of chemoresistance remains a major cause of cancer mortality due to the limited accessibility of targeted or immune therapies. However, given that severe alterations of molecular features during epithelial‐to‐mesenchymal transition (EMT) lead to acquired chemoresistance, emerging studies have focused on identifying targetable drivers associated with acquired chemoresistance. Particularly, AXL, a key receptor tyrosine kinase that confers resistance against targets and chemotherapeutics, is highly expressed in mesenchymal cancer cells. However, the underlying mechanism of AXL induction in mesenchymal cancer cells is poorly understood. Our study revealed that the YAP signature, which was highly enriched in mesenchymal‐type lung cancer, was closely correlated to AXL expression in 181 lung cancer cell lines. Moreover, using isogenic lung cancer cell pairs, we also found that doxorubicin treatment induced YAP nuclear translocation in mesenchymal‐type lung cancer cells to induce AXL expression. Additionally, the concurrent activation of TGFβ signaling coordinated YAP‐dependent AXL expression through SMAD4. These data suggest that crosstalk between YAP and the TGFβ/SMAD axis upon treatment with chemotherapeutics might be a promising target to improve chemosensitivity in mesenchymal‐type lung cancer.

Abbreviations

AUC
area under the curve
AXL
AXL receptor tyrosine kinase
BCL2
B‐cell lymphoma 2
CTD2
cancer target discovery and development
CTGF
connective tissue growth factor
DEG
differentially expressed genes
DOXO
doxorubicin
EMT
epithelial–mesenchymal transition
Eto
etoposide
FDA
Food and Drug Administration
ITGB3
integrin beta‐3
MAPK
mitogen‐activated protein kinase
MMP2
matrix metalloproteinase‐2
MMP9
matrix metalloproteinase‐9
mRNA
messenger RNA
NF‐κB
nuclear factor kappa‐light‐chain‐enhancer of activated B cells
SBE
SMAD binding element
SERPINE1
serpin family E member 1
siRNA
small interfering RNA
ssGSEA
single‐sample gene set enrichment analysis
TCGA
The Cancer Genome Atlas
TGFβ
transforming growth factor beta
YAP
Yes‐associated protein
YAP8SA
mutants of inhibitory phosphorylation site at eight serine to Alanine of YAP
ZEB1
zinc finger E‐box binding homeobox 1
ZEB2
zinc finger E‐box‐binding homeobox 2
  相似文献   
3.
4.

Objective

The advantage of arteriovenous fistulas (AVFs) in older patients requiring dialysis is controversial. We reviewed our vascular access experience in patients ≥70 years of age (older group) compared with younger patients.

Methods

We analyzed consecutive patients who underwent access surgery between 2013 and 2016. Primary success (PS) and primary patency (PP) data were analyzed between the older and younger groups before and after propensity score matching of the patients' characteristics and access composition. PS was defined as the achievement of access function that was amenable to two sessions of successful cannulation without early occlusion or maturation failure requiring revision. PP was defined as the time with uninterrupted patency without intervention.

Results

A total of 594 consecutive accesses were created among 563 patients, of whom 119 were allocated into each group after propensity score matching. In the whole cohort, 193 accesses (32.5%) were performed in older patients. AVFs were performed in 130 (67.4%) older patients and 293 (73.1%) younger patients. Regarding AVFs, the PS rate (83.6% in the older group vs 94.3% in the younger group; P = .001) and the overall PP at 6 and 12 months (73.1% and 57.1%, respectively, in the older group vs 86.7% and 77.7%, respectively, in the younger group; P = .009) were lower in the older group than in the younger group. However, no differences were found in the PS and PP rates for arteriovenous grafts between groups. Regarding the AVF location, the PS rate for forearm AVFs was significantly lower in the older group than in the younger group (76% vs 93%; P < .001); however, the PS rate of the upper arm was not different between the groups (94% vs 97%; P = .425). In the patients with PS, the PP rate of AVFs was similar between the two groups. In the older group with forearm AVFs, the median diameter of the radial artery was larger in the patients with PS than in the patients without PS (2.20 mm with PS vs 2.00 mm without PS; P = .008). The propensity score matching results demonstrated similar trends for the whole cohort, with lower PS (P = .042) and PP rates (P = .023) for AVF in the older group.

Conclusions

The outcomes after AVF were poorer in the older group than in the younger group, which was primarily due to unsatisfactory outcomes in patients with forearm AVFs. Thus, stricter criteria, especially regarding the radial artery diameter, should be applied for forearm AVFs in older patients, and additional research is necessary to delineate the risk factors for primary failure.  相似文献   
5.

Background

In Leriche syndrome, postoperative graft thrombosis remains one of the most significant clinical challenges.

Methods

We reviewed 51 patients who underwent surgery for aortoiliac occlusive disease at our hospital from January 2007 to December 2014. The factors associated with graft patency were determined using the Cox proportional hazard model.

Results

The 2-year prosthetic graft patency rate was 72.5%. Younger age (p = 0.017, Odd ratio (OR) = 1.112), postoperative uncontrolled hypertension (p = 0.044, OR = 3.797), and associated Trans Atlantic Inter-Society Consensus for the Management of Peripheral Arterial Disease II (TASC II) D femoropopliteal lesion (p = 0.008, OR = 11.139) were significantly related factors for prosthetic graft patency after surgical repair. The existing comorbidities of the patients that indicated the need for axillo-bifemoral bypass seemed to be related to lower graft patency or other complications.

Conclusions

For better graft patency after an open surgical repair of Leriche syndrome, strict postoperative hypertension control and distal run-off resolution are necessary.  相似文献   
6.
7.
8.
9.
10.
被称之为蒙医传统五种疗法之首的陶拉布日(下泻)疗法在临床应用有越来越少的趋势。这主要是因为陶拉布日疗法的服药方法略繁琐所致。陶拉布日疗法服药方法有三个步骤:即下泻施治前的准备,泻药的使用和善后调理。服药前的准备又有远近之分。泻药的使用包括配方、服法、洗肠、下泻程度和辅助疗法等五个部分。陶拉布日疗法又分为峻泻剂与缓泻剂两种。缓泻剂可无需实施施治前的准备和善后调理,直接用药,不会影响患者的工作学习,所以被广泛应用于临床。  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