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   4222篇
  免费   364篇
  国内免费   11篇
耳鼻咽喉   15篇
儿科学   137篇
妇产科学   150篇
基础医学   576篇
口腔科学   52篇
临床医学   583篇
内科学   738篇
皮肤病学   73篇
神经病学   403篇
特种医学   102篇
外科学   354篇
综合类   54篇
一般理论   4篇
预防医学   604篇
眼科学   153篇
药学   275篇
中国医学   6篇
肿瘤学   318篇
  2023年   55篇
  2022年   32篇
  2021年   139篇
  2020年   103篇
  2019年   176篇
  2018年   164篇
  2017年   109篇
  2016年   118篇
  2015年   136篇
  2014年   163篇
  2013年   228篇
  2012年   349篇
  2011年   317篇
  2010年   175篇
  2009年   163篇
  2008年   231篇
  2007年   240篇
  2006年   246篇
  2005年   238篇
  2004年   240篇
  2003年   223篇
  2002年   217篇
  2001年   34篇
  2000年   24篇
  1999年   23篇
  1998年   34篇
  1997年   33篇
  1996年   28篇
  1995年   27篇
  1994年   28篇
  1993年   24篇
  1992年   19篇
  1991年   13篇
  1990年   9篇
  1989年   14篇
  1988年   11篇
  1987年   6篇
  1986年   14篇
  1985年   6篇
  1984年   18篇
  1983年   17篇
  1982年   15篇
  1981年   16篇
  1980年   15篇
  1978年   12篇
  1977年   8篇
  1976年   10篇
  1972年   7篇
  1970年   6篇
  1968年   5篇
排序方式: 共有4597条查询结果,搜索用时 31 毫秒
1.
Circulating tumor cells (CTCs) in the blood of cancer patients are of high clinical relevance. Since detection and isolation of CTCs often rely on cell dimensions, knowledge of their size is key. We analyzed the median CTC size in a large cohort of breast (BC), prostate (PC), colorectal (CRC), and bladder (BLC) cancer patients. Images of patient‐derived CTCs acquired on cartridges of the FDA‐cleared CellSearch® method were retrospectively collected and automatically re‐analyzed using the accept software package. The median CTC diameter (μm) was computed per tumor type. The size differences between the different tumor types and references (tumor cell lines and leukocytes) were nonparametrically tested. A total of 1962 CellSearch® cartridges containing 71 612 CTCs were included. In BC, the median computed diameter (CD) of patient‐derived CTCs was 12.4 μm vs 18.4 μm for cultured cell line cells. For PC, CDs were 10.3 μm for CTCs vs 20.7 μm for cultured cell line cells. CDs for CTCs of CRC and BLC were 7.5 μm and 8.6 μm, respectively. Finally, leukocytes were 9.4 μm. CTC size differed statistically significantly between the four tumor types and between CTCs and the reference data. CTC size differences between tumor types are striking and CTCs are smaller than cell line tumor cells, whose size is often used as reference when developing CTC analysis methods. Based on our data, we suggest that the size of CTCs matters and should be kept in mind when designing and optimizing size‐based isolation methods.

Abbreviations

ACCEPT
Automated CTC Classification, Enumeration, and PhenoTyping software
BC
breast cancer
BLC
bladder cancer
CD
computed diameter
CEL
cultured tumor cell (cell line)
CK
cytokeratin
CRC
colorectal cancer
CTC‐L
circulating tumor cells derived from cerebrospinal fluid (liquor)
CTCs
circulating tumor cells
DAPI
4′6‐diamidino‐2‐phenylindole
EMT
epithelial–mesenchymal transition
EpCAM
epithelial cell adhesion molecule
IQR
interquartile range
KW test
Kruskal–Wallis test
MWU test
Mann–Whitney U test
NCR
nucleus/cytoplasm ratio
P2A
perimeter to area
PC
prostate cancer
TIF
tagged Image Format files
TXT
text file
μm
micrometer
µm2
square micrometers
  相似文献   
2.
BackgroundA venous leg ulcer is a chronic leg wound caused by poor venous blood circulation in the lower limbs. It is a recurring condition causing pain, malodour, reduced mobility, and depression. Randomised controlled trials evaluating treatments for venous leg ulcers provide important evidence to inform clinical decision-making. However, for findings to be useful, outcomes need to be clinically meaningful, consistently reported across trials, and fully reported. Research has identified the large number of outcomes reported in venous leg ulcer trials, impacting both synthesis of results, and clinical decision-making. To address this, a core outcome set will be developed. A core outcome set is an agreed standardised set of outcomes which should be, as a minimum, measured and reported in all trials which evaluate treatment effectiveness for a given indication. A core outcome set has the potential to reduce research waste, improve the utility of RCTs, reduce reporting bias, facilitate treatment comparisons across different sources of evidence and expedite the production of systematic reviews, meta-analyses and evidence-based clinical guidelines.AimThe aim of this project is to develop a core outcome set for research evaluating the effectiveness of interventions for treating venous leg ulceration.MethodsThrough a scoping review of the literature on venous leg ulceration, we will firstly identify a list of candidate outcome domains (broad categories in relation to what is being measured) from randomised controlled trials and qualitative research, and outcomes (specific methods in relation to what is being measured). In two further stages, we will use the resulting lists of outcome domains and outcomes to design two online surveys. A range of stakeholders will be invited to participate in the surveys and they will be asked to indicate which outcome domains and outcomes are most important and should be considered as core in future research reports.  相似文献   
3.
4.
5.
6.
Early childhood growth and development is conditioned by the consecutive events belonging to perinatal programming. This critical window of life will be very sensitive to any event altering programming of the main body functions.Programming of gut function, which is starting right after conception, relates to a very well-established series of cellular and molecular events associating all types of cells present in this organ, including neurons, endocrine and immune cells. At birth, this machinery continues to settle with the establishment of extra connection between enteric and other systemic systems and is partially under the control of gut microbiota activity, itself being under the densification and the diversification of microorganisms' population. As thus, any environmental factor interfering on this pre-established program may have a strong incidence on body functions. For all these reasons, pregnant women, fetuses and infants will be particularly susceptible to environmental factors and especially food contaminants. In this review, we will summarize the actual understanding of the consequences of repeated low-level exposure to major food contaminants on gut homeostasis settlement and on brain/gut axis communication considering the pivotal role played by the gut microbiota during the fetal and postnatal stages and the presumed consequences of these food toxicants on the individuals especially in relation with the risks of developing later in life non-communicable chronic diseases.  相似文献   
7.
8.

Objectives

This study reported a hospital outbreak due to an extensively drug-resistant (XDR) OXA-72-producing strain of Acinetobacter baumannii (A. baumannii).

Methods and Results

The isolates were found to be genotypically indistinguishable by whole-genome multiple locus sequence typing, and to belong to the international clonal complex CC2. One of these isolates sequentially developed a high resistance to colistin and rifampicin under treatment, as a result of mutations in genes pmrB and rpoB, respectively. The blaOXA-72 gene was localised on a 10-kb transferable plasmid, named pAB-STR-1, whose sequence is nearly identical to that of another plasmid previously found in Lithuanian strains, pAB120.

Conclusion

This report highlighted the need to carefully monitor the emergence of colistin and rifampicin resistance in patients treated for infections with multidrug-resistant A. baumannii.  相似文献   
9.
Emotional difficulties have been observed in individuals with eating disorders across awide range of studies, including poor interoceptive awareness, confusion of emotional states and difficulties with emotional language. Literature has linked these difficulties with emotional functioning as being an important factor related to the core aetiology ofeating disorders, however limited knowledge exists to how this impacts on professionalability to engage patients within treatment as a result of such dysfunction. Using aqualitative design this paper explores how facets of Emotional intelligence (EI) are related to the experience of an eating disorder. The study sampled a total of 32 participants with either a professional background working with eating disorders (n=27)or participants with personal lived experience (n=5), with a number of the participants (n=13) identified as having dual roles. The findings of the study show that aspects of EIsuch as emotional regulation and lack of an emotional language are considered to beat the core of the onset and maintenance of these disorders. Additional aspects of emotional awareness and expression were found to be related to treatment disengagement and difficulties. Building on previous literature, this paper found suchemotional deficits as a transdiagnostic issue rather than specifically anorexia nervosa. Furthermore, such dysfunction was seen by professionals to have a considerable impact on therapeutic relationships and successful treatment. These findings provide insight into the potential applications that EI may have in addressing aspects of theeating disorder to create better outcomes for treatment and intervention models.  相似文献   
10.
Phoenixin (PNX) is a neuropeptide shown to play roles in the control of reproduction. The nucleus of the solitary tract (NTS), a critical autonomic integrating centre in the hindbrain, is one of many areas with dense expression of PNX. Using coronal NTS slices obtained from male Sprague‐Dawley rats, the present study characterised the effects of PNX on both spike frequency and membrane potential of NTS neurones. Extracellular recordings demonstrated that bath‐applied 10 nmol L‐1 PNX increased the firing frequency in 32% of NTS neurones, effects which were confirmed with patch‐clamp recordings showing that 50% of NTS neurones tested depolarised in response to application of the peptide. Surprisingly, the responsiveness to PNX in NTS neurones then declined suddenly to 9% (P < 0.001). This effect was subsequently attributed to stress associated with construction in our animal care facility because PNX responsiveness was again observed in slices from rats delivered and maintained in a construction‐free facility. We then examined whether this loss of PNX responsiveness could be replicated in rats placed on a chronic stress regimen involving ongoing corticosterone (CORT) treatment in the construction‐free facility. Slices from animals treated in this way showed a similar lack of neuronal responsiveness to PNX (9.1 ± 3.9%) within 2 weeks of CORT treatment. These effects were specific to PNX responsiveness because CORT treatment had no effect on the responsiveness of NTS neurones to angiotensin II. These results are the first to implicate PNX with respect to directly controlling the excitability of NTS neurones and also provide intriguing data showing the plasticity of these effects associated with environmental and glucocorticoid stress levels of the animal.  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