全文获取类型
收费全文 | 2300篇 |
免费 | 196篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 38篇 |
妇产科学 | 36篇 |
基础医学 | 347篇 |
口腔科学 | 51篇 |
临床医学 | 216篇 |
内科学 | 468篇 |
皮肤病学 | 97篇 |
神经病学 | 352篇 |
特种医学 | 87篇 |
外科学 | 237篇 |
综合类 | 12篇 |
一般理论 | 2篇 |
预防医学 | 154篇 |
眼科学 | 33篇 |
药学 | 212篇 |
中国医学 | 4篇 |
肿瘤学 | 148篇 |
出版年
2023年 | 54篇 |
2022年 | 76篇 |
2021年 | 137篇 |
2020年 | 84篇 |
2019年 | 109篇 |
2018年 | 117篇 |
2017年 | 80篇 |
2016年 | 104篇 |
2015年 | 118篇 |
2014年 | 118篇 |
2013年 | 148篇 |
2012年 | 189篇 |
2011年 | 181篇 |
2010年 | 97篇 |
2009年 | 95篇 |
2008年 | 116篇 |
2007年 | 104篇 |
2006年 | 118篇 |
2005年 | 103篇 |
2004年 | 85篇 |
2003年 | 56篇 |
2002年 | 67篇 |
2001年 | 27篇 |
2000年 | 18篇 |
1999年 | 13篇 |
1998年 | 8篇 |
1997年 | 5篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 6篇 |
1988年 | 4篇 |
1987年 | 3篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1980年 | 3篇 |
1976年 | 2篇 |
1973年 | 2篇 |
1959年 | 4篇 |
1949年 | 2篇 |
1938年 | 1篇 |
1934年 | 2篇 |
1933年 | 1篇 |
1930年 | 2篇 |
1929年 | 2篇 |
1925年 | 1篇 |
1923年 | 1篇 |
排序方式: 共有2509条查询结果,搜索用时 62 毫秒
71.
Gaunitz Franziska Thomas Andreas Fietzke Mathias Franz Florian Auwärter Volker Thevis Mario Mercer-Chalmers-Bender Katja 《International journal of legal medicine》2019,133(4):1049-1064
International Journal of Legal Medicine - Despite the increasing relevance of synthetic cannabinoids as one of the most important classes within “New Psychoactive Substances”, there is... 相似文献
72.
Maximilian Methling Franziska Krumbiegel Sven Hartwig Maria K. Parr Michael Tsokos 《Forensic science, medicine, and pathology》2019,15(1):23-30
The role of psychoactive substances in the treatment of mental disorders and the risk of suicide are major public health issues. This cross-sectional study examined the prevalence of antidepressants and antipsychotics detected in toxicological screenings in suicides. Cases from the Institute of Legal Medicine of the Charité-University Medicine Berlin were reviewed over a 4-year-period. All cases (n = 477) with positive toxicology for antidepressants and antipsychotics in blood or organ tissue were included. Frequencies of the detected substances in non-suicide cases (n = 212; male n = 177, 55.2%; female n = 95, 52.5%) and suicide cases (n = 235; male n = 149, 63.4%; female n = 86, 36.6%) were examined. Tricyclic antidepressants (48.1%) were found most frequently in suicides, followed by atypical neuroleptics (37.0%), selective serotonin reuptake inhibitors (28.1%), typical neuroleptics (17.4%), tetracyclic antidepressants (16.2%) and other substances (8.9%). Alcohol was detected in 37.2% of suicides. The leading cause of death was drug poisoning (35.6%) followed by polytrauma (26.8%) and death by hanging (18.5%). A mental disorder (depression, schizophrenia, bipolar disorder, suicidality) was known in 22.9% of suicides. The most common location of death was the person’s own house (63.8%) followed by public places (28.1%) and hospitals (8.1%) The five most common substances in the suicide group were doxepin (20%) citalopram (15.3%), mirtazapine (14.9%), quetiapine (13.6%) and amitriptyline (12.3%). Toxicological findings from cross-sectional studies provide insight into how often certain types of antidepressants and antipsychotics are associated with suicide. A complementary approach is valuable for assessing the risk of suicide during medical treatment because the various available approaches (analysis of suicidal behavior/ideation, toxicity of drugs) each have strengths and limitations. 相似文献
73.
74.
75.
Franziska U. C. E. Jung Claudia Luck-Sikorski Hans-Helmut König Steffi G. Riedel-Heller 《Obesity surgery》2016,26(10):2393-2401
Background
Despite reported effectiveness, weight loss surgery (WLS) still remains one of the least preferred options for outpatient providers, especially in Germany. The aim of this study was to examine the effect of stigma and knowledge on recommendation of WLS and referral to a surgeon by general practitioners (GPs) and internists.Method
The sample consists of 201 GPs and internists from Germany. The questionnaire included questions on the perceived effectiveness of WLS, the frequency of recommendations of WLS, and the frequency of referral to WLS. Stigma, as well as knowledge was also assessed in this context. Linear and logistic regression models were conducted. A mediation analysis was carried out within post hoc analysis.Results
Knowledge (b?=?0.258, p?<?0.001) and stigma towards surgery (b?=??0.129, p?=?0.013) were related to the frequency of recommendation of WLS. Additionally, respondents, who were more likely to express negative attitudes towards WLS, were less likely to recommend WLS and thus refer patients to WLS (b?=??0.107, p?<?0.05). Furthermore, respondents with more expertise on WLS were more likely to recommend and thus refer patients to WLS (b?=?0.026, p?<?0.05).Conclusion
This study showed that stigma plays a role when it comes to defining treatment pathways for patients with obesity. The question remains how this might influence the patients and their decision regarding their treatment selection. Interventions are required to make treatment decisions by physicians or patients independent of social pressure due to stigma.76.
Thomas Riva Stefan Seiler Franziska Stucki Robert Greif Lorenz Theiler 《Paediatric anaesthesia》2016,26(12):1206-1208
In small children, high‐flow nasal cannula therapy may prolong apnea time even when an inspiratory oxygen fraction below 100% is used. This will be beneficial in prolonged intubation attempts, but especially during procedures requiring prolonged apnea time, leading to fewer airway manipulations and markedly enhanced surgical conditions. 相似文献
77.
Schmitter T Pils S Weibel S Agerer F Peterson L Buntru A Kopp K Hauck CR 《Infection and immunity》2007,75(8):4116-4126
Several pathogenic bacteria exploit human carcinoembryonic antigen-related cell adhesion molecules (CEACAMs) for adhesion to and invasion into their host cells. CEACAM isoforms have characteristic expression patterns on epithelial, endothelial, or hematopoietic cells, providing bacteria with distinct sets of receptors on particular tissues. For example, while CEACAM1 and CEACAM6 have a wide tissue distribution, CEACAM3, CEACAM4, and CEACAM8 are uniquely expressed on primary human granulocytes, whereas CEA and CEACAM7 are limited to epithelia. By reconstitution of a CEACAM-deficient cell line with individual CEACAMs, we have analyzed the requirements for CEACAM-mediated internalization of Neisseria gonorrhoeae. Our results point to two mechanistically different uptake pathways triggered by either epithelial CEACAMs (CEACAM1, CEA, and CEACAM6) or the granulocyte-specific CEACAM3. In particular, CEACAM3-mediated uptake critically depends on Src family protein tyrosine kinase (PTK) activity, and CEACAM3 associates with the SH2 domains of several Src PTKs. In contrast, epithelial CEACAMs require the integrity of cholesterol-rich membrane microdomains and are affected by cholesterol depletion, whereas CEACAM3-mediated uptake by transfected cells or the opsonin-independent phagocytosis by human granulocytes is not altered in the presence of cholesterol chelators. These results allow the subdivision of all human CEACAMs known to be utilized as pathogen receptors into functional groups and point to important consequences for bacterial engagement of distinct CEACAM isoforms. 相似文献
78.
Detection of Clostridium difficile toxin: comparison of enzyme immunoassay results with results obtained by cytotoxicity assay 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Musher DM Manhas A Jain P Nuila F Waqar A Logan N Marino B Graviss EA 《Journal of clinical microbiology》2007,45(8):2737-2739
Several kinds of laboratory techniques are available to detect Clostridium difficile toxin in fecal samples. Because questions have been raised about the reliability of immunoassays compared to the accepted standard, cytotoxicity assay, we studied three enzyme immunoassays (EIAs) and one rapid EIA, which demonstrated relatively good sensitivities and specificities compared to cytotoxicity assay. 相似文献
79.
Correlation between recent thymic emigrants and CD31+ (PECAM-1) CD4+ T cells in normal individuals during aging and in lymphopenic children 总被引:1,自引:0,他引:1
Junge S Kloeckener-Gruissem B Zufferey R Keisker A Salgo B Fauchere JC Scherer F Shalaby T Grotzer M Siler U Seger R Güngör T 《European journal of immunology》2007,37(11):3270-3280
CD31(+)CD45RA(+)RO(-) lymphocytes contain high numbers of T cell receptor circle (TREC)-bearing T cells; however, the correlation between CD31(+)CD4(+) lymphocytes and TREC during aging and under lymphopenic conditions has not yet been sufficiently investigated. We analyzed TREC, telomere length and telomerase activity within sorted CD31(+) and CD31(-) CD4(+) lymphocytes in healthy individuals from birth to old age. Sorted CD31(+)CD45RA(+)RO(-) naive CD4(+) lymphocytes contained high TREC numbers, whereas CD31(+)CD45RA(-)RO(+) cells (comprising < or =5% of CD4(+) cells during aging) did not contain TREC. CD31(+) overall CD4(+) cells remained TREC rich despite an age-related tenfold reduction from neonatal (100 : 1000) to old age (10 : 1000). Besides a high TREC content, CD31(+)CD45RA(+)RO(-)CD4(+) cells exhibited significantly longer telomeres and higher telomerase activity than CD31(-)CD45RA(+)RO(-)CD4(+) cells, suggesting that CD31(+)CD45RA(+)RO(-)CD4(+) cells represent a distinct population of naive T cells with particularly low replicative history. To analyze the value of CD31 in lymphopenic conditions, we investigated six children after allogeneic hematopoietic stem cell transplantation (HSCT). Reemerging overall CD4(+) as well as naive CD45RA(+)RO(-)CD4(+) cells predominantly expressed CD31 and correlated well with the recurrence of TREC 5-12 months after HSCT. Irrespective of limitations in the elderly, CD31 is an appropriate marker to monitor TREC-rich lymphocytes essentially in lymphopenic children after HSCT. 相似文献
80.
Mechanisms of toxicity associated with six tyrosine kinase inhibitors in human hepatocyte cell lines
下载免费PDF全文
![点击此处可从《Journal of applied toxicology : JAT》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Cécile Mingard Franziska Paech Jamal Bouitbir Stephan Krähenbühl 《Journal of applied toxicology : JAT》2018,38(3):418-431
Tyrosine kinase inhibitors have revolutionized the treatment of certain cancers. They are usually well tolerated, but can cause adverse reactions including liver injury. Currently, mechanisms of hepatotoxicity associated with tyrosine kinase inhibitors are only partially clarified. We therefore aimed at investigating the toxicity of regorafenib, sorafenib, ponatinib, crizotinib, dasatinib and pazopanib on HepG2 and partially on HepaRG cells. Regorafenib and sorafenib strongly inhibited oxidative metabolism (measured by the Seahorse‐XF24 analyzer) and glycolysis, decreased the mitochondrial membrane potential and induced apoptosis and/or necrosis of HepG2 cells at concentrations similar to steady‐state plasma concentrations in humans. In HepaRG cells, pretreatment with rifampicin decreased membrane toxicity (measured as adenylate kinase release) and dissipation of adenosine triphosphate stores, indicating that toxicity was associated mainly with the parent drugs. Ponatinib strongly impaired oxidative metabolism but only weakly glycolysis, and induced apoptosis of HepG2 cells at concentrations higher than steady‐state plasma concentrations in humans. Crizotinib and dasatinib did not significantly affect mitochondrial functions and inhibited glycolysis only weakly, but induced apoptosis of HepG2 cells. Pazopanib was associated with a weak increase in mitochondrial reactive oxygen species accumulation and inhibition of glycolysis without being cytotoxic. In conclusion, regorafenib and sorafenib are strong mitochondrial toxicants and inhibitors of glycolysis at clinically relevant concentrations. Ponatinib affects mitochondria and glycolysis at higher concentrations than reached in plasma (but possibly in liver), whereas crizotinib, dasatinib and pazopanib showed no relevant toxicity. Mitochondrial toxicity and inhibition of glycolysis most likely explain hepatotoxicity associated with regorafenib, sorafenib and possibly pazopanib, but not for the other compounds investigated. 相似文献