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101.
Structural and functional analysis of de‐N‐acetylase PgaB from periodontopathogen Aggregatibacter actinomycetemcomitans
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C. Parthiban D. Varudharasu M. Shanmugam P. Gopal C. Ragunath L. Thomas M. Nitz N. Ramasubbu 《Molecular oral microbiology》2017,32(4):324-340
The oral pathogen Aggregatibacter actinomycetemcomitans uses pga gene locus for the production of an exopolysaccharide made up of a linear homopolymer of β‐1,6‐N‐acetyl‐d ‐glucosamine (PGA). An enzyme encoded by the pgaB of the pga operon in A. actinomycetemcomitans is a de‐N‐acetylase, which is used to alter the PGA. The full length enzyme (AaPgaB) and the N‐terminal catalytic domain (residues 25–290, AaPgaBN) from A. actinomycetemcomitans were cloned, expressed and purified. The enzymatic activities of the AaPgaB enzymes were determined using 7‐acetoxycoumarin‐3‐carboxylic acid as the substrate. The AaPgaB enzymes displayed significantly lower de‐N‐acetylase activity compared with the activity of the deacetylase PdaA from Bacillus subtilis, a member of the CE4 family of enzymes. To delineate the differences in the activity and the active site architecture, the structure of AaPgaBN was determined. The AaPgaBN structure has two metal ions in the active site instead of one found in other CE4 enzymes. Based on the crystal structure comparisons among the various CE4 enzymes, two residues, Q51 and R271, were identified in AaPgaB, which could potentially affect the enzyme activity. Of the two mutants generated, Q51E and R271K, the variant Q51E showed enhanced activity compared with AaPgaB, validating the requirement that an activating aspartate residue in the active site is essential for higher activity. In summary, our study provides the first structural evidence for a di‐nuclear metal site at the active site of a member of the CE4 family of enzymes, evidence that AaPgaBN is catalytically active and that mutant Q51E exhibits higher de‐N‐acetylase activity. 相似文献
102.
Walid Kamal Abdelbasset Gopal Nambi Marwa M Eid Safaa M Elkholi 《World Journal of Psychiatry》2021,11(12):1267-1273
The corona virus disease 2019 (COVID-19) pandemic has resulted in most nations deciding upon self-isolation and social distancing policies for their citizens to control the pandemic and reduce hospital admission. This review aimed at evaluating the effect of physical activity on mental well-being during the COVID-19 pandemic. It was concluded that the COVID-19 pandemic may lead to augmented levels of angiotensin-converting enzyme (ACE)-2 that led to cardiovascular and neurological disorders associated with highly inflammatory effects of viral infection affecting the brain tissues leading to damage of the nervous system and resulting in cognition dysfunction, insulin sensitivity reduction, and behavioral impairments. Anxiety and depression may lead to negative effects on various quality of life domains, such as being physically inactive. Regular physical activities may reduce inflammatory responses, improve ACE-2 responses, and improve mental well-being during self-isolation and social distancing policies related to the COVID-19 pandemic. Further studies should be conducted to assess the different intensities of physical activities on cardiova scular function, and mental well-being during the COVID-19 pandemic. 相似文献
103.
Upadhyaya VD Gopal SC Gangopadhyaya AN Gupta DK Sharma S Upadyaya A Kumar V Pandey A 《World journal of surgery》2007,31(12):2412-2415
Objective The aim of this study was to characterize a successful approach for the management of infants with long-gap esophageal atresia
(EA) with tracheoesophageal fistula (TEF). The goal was to preserve the native esophagus and minimize the incidence of esophageal
anastomotic leaks using fibrin glue as a sealant over the esophageal anastomosis.
Method A total of 52 patients were evaluated in this study. Only patients in whom, gap between the two ends of the esophagus was
≥ 2 cm were selected during January 2005 to January 2007. Patients were divided in two groups on the basis of block randomization.
Group A comprised the patients in whom fibrin sealant was used as reinforcement on a primary end-to-end esophageal anastomosis;
in group B, fibrin glue was not used. The two groups were compared in terms of esophageal anastomotic leak (EL), postoperative
esophageal stricture (ES), and mortality. The statistical analysis was done using Fisher’s exact test and the chi-squared
test.
Result The number of anastomotic leaks in group A (glue group) was about one-fifth that in group B (no glue group). The incidence
of ES was almost twice as high in group B as in group A. The mortality rate was almost threefold higher in group B (no-glue
group). The higher incidence of EL and ES in group B compared to group A was statistically significant.
Conclusion Thus, fibrin glue when used as an adjunct to esophageal anastomosis for primary repair of long-gap EA with TEF appears safe
in the clinical setting and may lower the chances of esophageal leak and anastomosis-site strictures. Hence, it can diminish
the mortality and morbidity of these patients. 相似文献
104.
Color Doppler Visualization of Intramyocardial Coronary Arteries Using a New Echo System: Effect of Contrast Enhancement and Vasodilation 总被引:9,自引:0,他引:9
Garcia Del Rio C Taylor GW Nanda NC Agrawal DI Agrawal GG Carvalho C Espinal M Becher H 《Echocardiography (Mount Kisco, N.Y.)》1996,13(6):645-650
Utilizing a new echocardiographic system, intramyocardial coronary arteries could be demonstrated by color Doppler in a small number of open chest animals. Both intravenous and intracoronary injections of a contrast agent (Levovist) resulted in significant enhancement of color flow signals with an increase in the length, width, and the number of these vessels. Similar results were obtained with intravenous infusion and direct intracoronary injections of a vasodilator (adenosine). 相似文献
105.
106.
Liping Zhang Emily C. Cherney Xiao Zhu Tai-an Lin Johnni Gullo-Brown Derrick Maley Kathy Johnston-Allegretto Lisa Kopcho Mark Fereshteh Christine Huang Xin Li Sarah C. Traeger Gopal Dhar Aravind Anandam Sandeep Mahankali Shweta Padmanabhan Prabhakar Rajanna Venkata Murali Thanga Mariappan Robert Borzilleri Gregory Vite John T. Hunt Aaron Balog 《ACS medicinal chemistry letters》2021,12(3):494
Indoleamine 2,3-dioxygenase 1 (IDO1) has been identified as a target for small-molecule immunotherapy for the treatment of a variety of cancers including renal cell carcinoma and metastatic melanoma. This work focuses on the identification of IDO1 inhibitors containing replacements or isosteres for the amide found in BMS-986205, an amide-containing, IDO1-selective inhibitor currently in phase III clinical trials. Detailed subsequently are efforts to identify a structurally differentiated IDO1 inhibitor via the pursuit of a variety of heterocyclic isosteres, leading to the discovery of highly potent, imidazopyridine-containing IDO1 inhibitors. 相似文献
107.
K. Gopal Kishor Kumar R. Nandini P. Jahan M. J. Mahesh Kumar 《Journal of thrombosis and thrombolysis》2010,30(2):154-163
We studied and compared the efficiency of induction aneurysm in apo E mice by using high fat diet and Ang II. Aneurysm induced
in 6 week old male apo E −/− mice by subcutaneous release of Ang II injection for 45 days. Also, aneurysm was induced in three
month old male apo E by administration of high fat diet for a period of three months. No difference in body weight in Ang
II treated mice. But, increase in body weight and mean arterial blood pressure observed in high fat diet group animals. Highly
significant increase in total cholesterol, TG, LDL and significant decrease in HDL level were observed in Ang II treated animals.
Significant increase in total cholesterol, but no changes in TG, LDL, HDL levels were observed in high fat diet group. Higher
percentage of circulating monocytes was observed in ang II treated group but more number of circulating lymphocytes were observed
in high fat diet group in FACS analysis. In histopathology, intimal layer of abdominal aorta was completely replaced by chronic
inflammatory cells particularly macrophages (80%) which appeared as foam cells and lymphocytes (20%) in ang II treated animals.
Degradation of elastin, infiltration of lymphocytes, chondrocytes and cellular migration towards media were observed in the
abdominal aorta of high fat diet group. Real time analysis and immunofluorescence assay supports over expression of Vcam 1
Icam1, MCP 1and MMP2 genes were observed in Ang II treated animals. In immunofluorescence assay, over expression of Mac 3
protein specific for macrophages was observed in abdominal aorta of ang II treated animals, but over expression of CD45.1
& 45.2 proteins specific to lymphocytes were observed in high fat diet group. Based on our observations, Ang II induced aortic
aneurysm by recruiting/ proliferating circulating monocytes by up regulating Icam-1, Vcam -1 and MCP-1. Also, ang II involved
in degradation of elastin in the abdominal aorta by up regulation of MMP2 to promote agranulocytes migration in the intimal
layers. Epithelial cell hyperplasia with accumulation of fatty fluids (cyst) was observed in seminal vesicle and ventral prostate
of high fat treated animals. Fatty degeneration, germ cell apoptosis and infiltration giant cells were observed in the testes
of high fat diet group. As per available literature these observations were not reported with high fat diet treatments with
apo E models. High fat diet induced aneurysm prominently in abdominal, thoracic aorta and extensive plaque formation was observed
in femoral and renal arteries. Administration of high fat diet containing cholesterol induced aneurysm in apo E mice model
also efficient method to rule out the pathogenesis of aortic aneurysm when compared with angiotensin. 相似文献
108.
Primary cutaneous lymphomas are defined as lymphoid neoplasms that present themselves clinically on the skin and do not have extra-cutaneous disease, when the diagnosis is made or even after 6 months of the diagnosis. Primary cutaneous lymphomas of B-cells are less frequent than lymphomas of T-cells. Primary B-cell lymphomas have a better prognosis than secondary B-cell lymphomas. Primary B-cell cutaneous lymphomas are classified into five types according to the World Health Organization and European Organization for Research and Treatment of Cancer classification. The primary diffuse large B-cell cutaneous lymphoma – leg type corresponds to approximately 5-10% of the B-cell cutaneous lymphomas. It is predominantly seen in elderly people and has a female preponderance. Skin lesions can be single, multiple, and even grouped. A 5-year survival rate ranges from 36 to 100% of the cases. The expression of Bcl-2, presence of multiple lesions, and involvement of both the upper limbs lead to a worse prognosis. Very few cases have been described in the literature. 相似文献
109.
Gopal Varma Rachel E. Clough Peter Acher Julien Sénégas Hannes Dahnke Stephen F. Keevil Tobias Schaeffter 《Magnetic resonance in medicine》2011,65(5):1483-1490
In magnetic resonance imaging, implantable devices are usually visualized with a negative contrast. Recently, positive contrast techniques have been proposed, such as susceptibility gradient mapping (SGM). However, SGM reduces the spatial resolution making positive visualization of small structures difficult. Here, a development of SGM using the original resolution (SUMO) is presented. For this, a filter is applied in k‐space and the signal amplitude is analyzed in the image domain to determine quantitatively the susceptibility gradient for each pixel. It is shown in simulations and experiments that SUMO results in a better visualization of small structures in comparison to SGM. SUMO is applied to patient datasets for visualization of stent and prostate brachytherapy seeds. In addition, SUMO also provides quantitative information about the number of prostate brachytherapy seeds. The method might be extended to application for visualization of other interventional devices, and, like SGM, it might also be used to visualize magnetically labelled cells. Magn Reson Med, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
110.
Noopur Raje Suresh Pai Sucheta Vaidya R. Gopal Purvish Parikh Tapankumar Saikia Vasant Pai Kanchan Nadkarni Ian Magrath Suresh Advani 《Leukemia & lymphoma》1994,14(3):285-290
A total of 42 adults with acute lymphoblastic leukemia were treated with an aggressive induction/consolidation chemotherapy (MCP-841) between June 1986 and December 1991. 32 patients (76.19%) achieved complete remission at the end of induction. There were 9 induction deaths, 6 of them due to infection. All patients received cranial irradiation in the dose of 20 Gy and intrathecal methotrexate for CNS prophylaxis. Twelve patients relapsed, 10 in the bone marrow, one case had isolated CNS relapse and the other relapsed in the bone marrow and CNS. The actuarial overall survival of all patients at the end of 5 years was 41.94%. Patient characteristics including age, sex, FAB morphology, phenotype, WBC count, platelet count and LDH did not influence survival significantly. 相似文献