全文获取类型
收费全文 | 3099篇 |
免费 | 222篇 |
国内免费 | 22篇 |
专业分类
耳鼻咽喉 | 23篇 |
儿科学 | 76篇 |
妇产科学 | 106篇 |
基础医学 | 453篇 |
口腔科学 | 66篇 |
临床医学 | 397篇 |
内科学 | 636篇 |
皮肤病学 | 88篇 |
神经病学 | 244篇 |
特种医学 | 78篇 |
外国民族医学 | 1篇 |
外科学 | 444篇 |
综合类 | 12篇 |
一般理论 | 2篇 |
预防医学 | 219篇 |
眼科学 | 52篇 |
药学 | 173篇 |
中国医学 | 2篇 |
肿瘤学 | 271篇 |
出版年
2023年 | 36篇 |
2022年 | 27篇 |
2021年 | 120篇 |
2020年 | 75篇 |
2019年 | 87篇 |
2018年 | 121篇 |
2017年 | 92篇 |
2016年 | 104篇 |
2015年 | 102篇 |
2014年 | 121篇 |
2013年 | 181篇 |
2012年 | 213篇 |
2011年 | 213篇 |
2010年 | 130篇 |
2009年 | 115篇 |
2008年 | 181篇 |
2007年 | 197篇 |
2006年 | 170篇 |
2005年 | 176篇 |
2004年 | 150篇 |
2003年 | 132篇 |
2002年 | 101篇 |
2001年 | 55篇 |
2000年 | 46篇 |
1999年 | 31篇 |
1998年 | 37篇 |
1997年 | 24篇 |
1996年 | 21篇 |
1995年 | 25篇 |
1994年 | 26篇 |
1993年 | 11篇 |
1992年 | 16篇 |
1991年 | 22篇 |
1990年 | 24篇 |
1989年 | 19篇 |
1988年 | 25篇 |
1987年 | 14篇 |
1986年 | 18篇 |
1985年 | 19篇 |
1984年 | 20篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1978年 | 3篇 |
1977年 | 7篇 |
1974年 | 3篇 |
1970年 | 3篇 |
1967年 | 2篇 |
1939年 | 2篇 |
排序方式: 共有3343条查询结果,搜索用时 15 毫秒
1.
2.
Theresa M. Thole Joern Toedling Annika Sprüssel Sebastian Pfeil Larissa Savelyeva David Capper Clemens Messerschmidt Dieter Beule Stefanie Groeneveld-Krentz Cornelia Eckert Guido Gambara Anton G. Henssen Sabine Finkler Johannes H. Schulte Anja Sieber Nils Bluethgen Christian R. A. Regenbrecht Annette Künkele Marco Lodrini Angelika Eggert Hedwig E. Deubzer 《International journal of cancer. Journal international du cancer》2020,146(4):1031-1041
Accurate modeling of intratumor heterogeneity presents a bottleneck against drug testing. Flexibility in a preclinical platform is also desirable to support assessment of different endpoints. We established the model system, OHC-NB1, from a bone marrow metastasis from a patient diagnosed with MYCN-amplified neuroblastoma and performed whole-exome sequencing on the source metastasis and the different models and passages during model development (monolayer cell line, 3D spheroid culture and subcutaneous xenograft tumors propagated in mice). OHC-NB1 harbors a MYCN amplification in double minutes, 1p deletion, 17q gain and diploid karyotype, which persisted in all models. A total of 80–540 single-nucleotide variants (SNVs) was detected in each sample, and comparisons between the source metastasis and models identified 34 of 80 somatic SNVs to be propagated in the models. Clonal reconstruction using the combined copy number and SNV data revealed marked clonal heterogeneity in the originating metastasis, with four clones being reflected in the model systems. The set of OHC-NB1 models represents 43% of somatic SNVs and 23% of the cellularity in the originating metastasis with varying clonal compositions, indicating that heterogeneity is partially preserved in our model system. 相似文献
3.
Case report: Fatal hepatic failure after aortic valve replacement and sevoflurane exposure 总被引:1,自引:0,他引:1
Andreas Lehmann Michael Neher Arndt-Holger Kiessling Frank Isgro Anette Koloska Joachim Boldt 《Journal canadien d'anesthésie》2007,54(11):917-921
PURPOSE: To report a case of lethal hepatotoxicity possibly caused by sevoflurane. CLINICAL FEATURES: A 76-yr-old woman with a history of four previous minor surgical procedures developed acute liver failure after general anesthesia with sevoflurane, sufentanil and propofol for aortic valve replacement. After an uneventful procedure the patient was extubated 4.5 hr after surgery. On the second postoperative day, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) increased. On the third postoperative day liver failure occurred, ALT peaked at 10504 UxL(-1) and AST at 15516 UxL(-1), and coagulopathy with an international normalized ratio of 4.6 developed. Liver transplantation was considered but rejected as a therapeutic option. The patient died three days after the operation in multiple organ failure triggered by hepatic failure. Other possible causes for liver failure were excluded. CONCLUSIONS: Sevoflurane hepatitis as a cause for liver failure may be implicated in this patient undergoing valve surgery. Unlike other halogenated anesthetic drugs, sevoflurane is not metabolized to hepatotoxic trifluoroacetyl proteins. However, compound A may react with proteins and may be transformed into antigenic material. We suggest that all halogenated anesthetics may be implicated with acute liver injury. 相似文献
4.
J. Boldt H. A. Adams B. Zickmann D. Kling G. Hempelmann 《European journal of clinical pharmacology》1990,38(5):431-436
Summary The release of endogenous catecholamines in aorto-coronary bypass graft patients receiving either 0.5 mg/kg enoximone (n=10), 4.0 mg/kg theophylline (n=10) or saline solution (control,n=10) has been studied, as well as certain haemodynamic parameters. Adrenaline (A) and noradrenaline (NA) concentrations were
not significantly changed by the administration of enoximone. Theophylline caused a small increase in NA (+ 40% in the 1st
min) and a marked increase in A (approximately + 7000% in the 1st min), which still remained elevated at the end of the investigation
period (+ 220% in the 30th min). The major haemodynamic effects of enoximone were a significant increase in cardiac index
(CI; + 35%) and a decrease in pulmonary capillary wedge pressure (PCWP; −27%), pulmonary artery pressure (PAP; −21%), RVEDV
and RVESV, while the heart rate (HR) remained almost unchanged. The dominant haemodynamic effects of theophylline were an
increase in HR (+ 26%; arrhythmia in 3 patients), PAP (+ 22%), and RVEDV (+ 19%), while REVESV (+ 26%), MAP (−16%), CI (−14%),
and RVEF (−15%) fell significantly.
It is concluded that the haemodynamic actions of enoximone are not mediated by catecholamine release, whereas the adverse
cardiovascular effects of theophylline might partly be explained by the significant increase in plasma adrenaline. 相似文献
5.
STUDY OBJECTIVE: To test the hypothesis that induced human graafian follicles consist of different steroidogenic cell types on the basis of their light scatter characteristics as determined by flow cytometry. DESIGN: Cross-sectional, observational study. SETTING: Flow cytometry laboratory. PATIENTS: Thirty-six follicular aspirates from nine consecutive patients undergoing in vitro fertilization for tubal factor infertility were evaluated. RESULTS: Two distinct luteal cell populations were recovered. Both populations were positive by Oil Red O staining, suggesting the presence of intracellular lipid. Neither population stained positively for the presence of HLe-1/CD45, an antigen present on all human leukocytes. CONCLUSIONS: Cellular heterogeneity exists within the granulosa cell compartment. 相似文献
6.
R A Steeves T G Murray E G Moros H C Boldt W F Mieler B R Paliwal 《International journal of hyperthermia》1992,8(4):443-449
Ferromagnetic (FM) thermoseeds and radioactive (125I) seeds were combined in an episcleral plaque to give concurrent hyperthermia and irradiation for enhanced tumour destruction. A Greene melanoma cell line was utilized to study the interaction between these treatment modalities. We attached five FM thermoseeds (with an operating temperature of 48 degrees C) in parallel with alternating rows of 125I seeds onto the inner surface of each 14 mm Silastic plaque. Plaques were centred over a 3-6 mm (diameter) intraocular melanoma in each rabbit. Some rabbits were then placed within a heating coil, and their eye tumours were warmed rapidly to therapeutic temperatures (43.6 degrees C across the tumour base) while the temperature of normal conjunctiva across the globe did not exceed 38.5 degrees C. Analysis of 49 treated eye melanomas showed 50% local tumour control at 41.7 Gy for 125I alone, whereas only 9.5 Gy were needed to give the same local control rate after 125I with concurrent FM hyperthermia. Thus, a thermal enhancement ratio of 4.4 was obtained. Hyperthermia alone gave a 20% tumour response rate, but responses were only temporary. We conclude that FM thermoseeds can be used to deliver biologically effective hyperthermia concurrently with radiation, thereby reducing the dose of radiation needed for tumour control. 相似文献
7.
Annika Reintam Pille Parm Uwe Redlich Liina-Mai Tooding Joel Starkopf Friedrich Köhler Claudia Spies Hartmut Kern 《BMC gastroenterology》2006,6(1):19-7
Background
While gastrointestinal problems are common in ICU patients with multiple organ failure, gastrointestinal failure has not been given the consideration other organ systems receive. The aim of this study was to evaluate the incidence of gastrointestinal failure (GIF), to identify its risk factors, and to determine its association with ICU mortality. 相似文献8.
9.
Peter Appelros Gunnel M Karlsson Annika Thorwalls Kerstin Tham Ingegerd Nydevik 《Journal of rehabilitation medicine》2004,36(6):258-261
OBJECTIVE: The Baking Tray Task is a comprehensible, simple-to-perform test for use in assessing unilateral neglect. The aim of this study was to validate further its use with stroke patients. METHODS: The Baking Tray Task was compared with 2 versions of the Behaviour Inattention Test and a test for personal neglect. A total of 270 patients were subjected to a 3-item version of the Behaviour Inattention Test and 40 patients were subjected to an 8-item version of the Behaviour Inattention Test, besides the Baking Tray Task and the personal neglect test. RESULTS: The Baking Tray Task was more sensitive than the 3-item Behaviour Inattention Test, but the 8-item Behaviour Inattention Test was more sensitive than the Baking Tray Task. The best combination of any 3 tests was Baking Tray Task, Reading an article, and Figure copying; the 2 last-mentioned being a part of the 8-item Behaviour Inattention Test. CONCLUSION: Multi-item tests detect more cases of neglect than do single tests. However, it is tiresome for the patient to undergo a larger test battery than necessary. It is also time-consuming for the staff. Behavioural tests seem more appropriate when assessing neglect. The Baking Tray Task seems to be one of the most sensitive single tests, but its sensitivity can be further enhanced when it is used in combination with other tests. 相似文献
10.
LPS resistance in monocytic cells caused by reverse signaling through transmembrane TNF (mTNF) is mediated by the MAPK/ERK pathway 总被引:1,自引:0,他引:1
Kirchner S Boldt S Kolch W Haffner S Kazak S Janosch P Holler E Andreesen R Eissner G 《Journal of leukocyte biology》2004,75(2):324-331
The transmembrane form of tumor necrosis factor (mTNF), expressed on activated monocytes (MO) and macrophages (MPhi), is able to induce apoptosis in human endothelial cells (EC). Apoptosis is mediated by two distinct mechanisms: direct cell contact and a yet-unidentified soluble protein, death factor X. In addition, mTNF acts as a receptor that transduces a "reverse signal" into MO/MPhi when bound to the TNF receptor on EC. Reverse signaling by mTNF confers resistance to bacterial lipopolysaccharide (LPS). Stimulation of reverse signaling by mTNF blocks the ability of MO/MPhi to produce death factor X and proinflammatory cytokines. We have investigated which signaling pathways are used by mTNF acting as receptor. Reverse signaling triggers two independent pathways that can be distinguished by protein kinase C (PKC) inhibitors. The suppression of LPS-induced death factor X is dependent on PKC, whereas the suppression of LPS-mediated cytokine release is not. LPS and reverse signaling stimulate the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway. It is interesting that the activation of reverse signaling by mTNF renders MO/MPhi refractory to a subsequent activation of the MAPK/ERK pathway by LPS. Thus, reverse signaling achieves LPS resistance in monocytic cells through interference with key signal-transduction pathways. 相似文献