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181.
Purpose
Chronic hepatitis B virus (HBV) infection is the major risk factor for hepatocellular carcinoma (HCC) in India. Studies from other countries have linked HBV genotype C to a higher risk for HCC. This study was carried out to determine the association between genotype and HCC and also the frequency of mutations in CTNNB1 (beta-catenin) and TP53 genes in HBV-related HCC.Methods
Formalin-fixed paraffin-embedded (FFPE) tissues from 20 (15 autopsy, five resected specimens) cases of HBV-associated HCC were examined. Viral genotype was determined by sequencing portions of the HBV S gene using four overlapping PCR amplicons. Exon 3 of CTNNB1 and exon 7 of TP53 were sequenced.Results
HBV genotyping was possible in 14 of 20 cases; genotype D was most common (n?=?11) followed by C (n?=?2) and A (n?=?1). CTNNB1 mutations were noted in two of 15 amplifiable cases while two of 10 specimens showed TP53 mutations.Conclusions
HBV genotype can be ascertained from FFPE sections by sequencing multiple overlapping fragments to avoid the limitation of fragmented DNA. Genotype D was the common genotype in HBV-associated HCC. The very low frequency of TP53 mutation suggests low levels of aflatoxin B1 exposure. The beta-catenin pathway appears not to be significantly involved in HBV-related HCC in India. However, further larger studies are required to confirm these findings. 相似文献182.
Serotonin type 3 (5-HT3) antagonists, which find an unflinching place in the management of nausea and emesis are presently screened for their neuro-pharmacological potential in various animal models. In the present study, 2-(4-methyl piperazin-1-yl)-1,8-naphthyridine-3-carbonitrile (NA-2) with an optimal log P and pA2 value comparable to that of ondansetron was screened in rodent models of depression. The acute and chronic (14 days) treatment of the synthetic compound exhibited antidepressant-like effects at the lower dose levels in mice forced swim test (FST). A typical and similar dose-immobility profile was observed in both mice FST and tail suspension test (TST). Interaction studies in FST revealed the reversal of mCPP induced immobility, attenuation of antidepressant effects of fluoxetine and desipramine. Chronic NA-2 treatment restored the behavioural deficits in olfactory bulbectomized (OBX) rats as indicated by reduction in hyperactivity in novel open field test. This preliminary study points to a serotonergic mechanism behind the antidepressant-like effects of NA-2 and invigorates further investigation of analogous compounds in various other models of depression. 相似文献
183.
April Brooks Grady Wick Damiano Rondelli José A. L. Arruda Kalyani Perumal Jerrold S. Levine 《Kidney》2009,18(3):125-128
Tumor lysis syndrome is an oncologic emergency characterized by electrolyte derangements and the frequent development of acute
renal failure. We describe a patient with acute lymphoblastic lymphoma in whom rapid and severe tumor lysis syndrome developed
within 10 h of the administration of a single dose of corticosteroid. Our case and a review of the literature indicate that
patients with lymphoproliferative malignancies given a single dose of corticosteroid may be at significant risk for rapid
and life-threatening tumor lysis syndrome. We recommend that such patients receive aggressive and frequent laboratory monitoring
even in the setting of appropriate prophylaxis. 相似文献
184.
Panneerselvam P Rather BA Ravi Sankar Reddy D Ramesh Kumar N 《European journal of medicinal chemistry》2009,44(5):2328-2333
In the present study, a series of novel Schiff bases were synthesized by condensation of 3-amino-6,8-dibromo-2-phenylquinazolin-4(3H)-ones with different aromatic aldehydes via cyclized intermediate 6,8-dibromo-2-phenyl benzoxazin-4-one. The chemical structures were confirmed by means of IR, (1)H NMR, (13)C NMR, Mass spectral and Elemental analysis. These compounds were screened for anti-bacterial (Staphylococcus aureus ATCC-9144, Staphylococcus epidermidis ATCC-155, Micrococcus luteus ATCC-4698, Bacillus cereus ATCC-11778, Escherichia coli ATCC-25922, Pseudomonas aeruginosa ATCC-2853, and Klebsiella pneumoniae ATCC-11298) and anti-fungal (Aspergillus niger ATCC-9029 and Aspergillus fumigatus ATCC-46645) activities by paper disc diffusion technique. The minimum inhibitory concentrations (MICs) of the compounds were also determined by agar streak dilution method. Among the synthesized compounds 3-(3,4,5-trimethoxybenzylideneamino)-6,8-dibromo-2-phenylquinazolin-4(3H)-one 10 was found to be the most potent anti-microbial activity with MICs of 18.9, 19.1, 18.8, 21.7, 18.2, 19.3, 16.7, 8.6 and 10.1 microg/ml against above mentioned respective strains. Compounds were found to exhibit more anti-fungal than anti-bacterial activity. 相似文献
185.
Palaniappan Senthilkumar Murugesan Dinakaran Yogesh Chandraseakaran Perumal Yogeeswari Dharmarajan Sriram 《Archiv der Pharmazie》2009,342(2):100-112
Fifty one newer 1‐(cyclopropyl/2,4‐difluorophenyl/tert‐butyl)‐1,4‐dihydro‐8‐methyl‐6‐nitro‐4‐oxo‐7‐(substituted secondary amino)quinoline‐3‐carboxylic acids were synthesized from 1,3‐dichloro‐2‐methylbenzene and evaluated for in‐vitro antimycobacterial activities against Mycobacterium tuberculosis H37Rv (MTB), multi‐drug resistant Mycobacterium tuberculosis (MDR‐TB), and Mycobacterium smegmatis (MC2). Among the synthesized compounds, 1‐cyclopropyl‐1,4‐dihydro‐7‐(3,4‐dihydro‐6,7‐dimethoxyisoquinolin‐2(1H)‐yl)‐8‐methyl‐6‐nitro‐4‐oxoquinoline‐3‐carboxylic acid 9p was found to be the most active compound in vitro with a MIC value of 0.39 μM against MTB. Against MDR‐TB, compound 7‐(2‐carboxy‐5,6‐dihydroimidazo[1,2‐a]pyrazin‐7(8H)‐yl)‐1‐cyclopropyl‐1,4‐dihydro‐8‐methyl‐6‐nitro‐4‐oxoquinoline‐3‐carboxylic acid 9n was found to be the most active with a MIC value of 0.09 μM. 相似文献
186.
187.
188.
Perumal J Zabad R Caon C MacKenzie M Tselis A Bao F Latif Z Zak I Lisak R Khan O 《Journal of neurology》2008,255(1):89-93
Objective
To investigate the long-term risk of developing MS in patients presenting with acute transverse myelitis (ATM) and normal
brain MRI scans at onset.
Methods
We studied 58 ATM patients with normal brain MRI at presentation for up to 5 years with serial neurologic and imaging studies.
All patients underwent CSF analysis at onset which was defined positive if two or more IgG oligoclonal bands and/or elevated
IgG index were present. Brain and spinal cord MRI scans were obtained every 6 months for the first 2 years, and annually thereafter
unless the patient experienced a second neurologic attack different from the initial episode to confirm CDMS or there was
demonstration of MRI lesions confirming dissemination in time and space to fulfill McDonald imaging criteria to diagnose MS.
Results
Seventeen of 58 (29%) patients developed MS of which 7 (41%) patients developed CDMS and 10 (59%) developed MS using McDonald
Imaging Criteria. Mean time to CDMS by a second clinical attack was 11. 1 months compared to 19. 2 months by MRI lesions (P = 0. 03). None of the patients developed MS after 24 months of onset. All 17 patients who developed MS had positive CSF although
15 patients who had positive CSF did not develop MS during the 5 years of follow-up.
Conclusions
The majority of patients with ATM and normal brain MRI do not develop MS after 5 years of follow-up confirming the relatively
low risk compared to patients with abnormal brain MRI scans. CSF is helpful in distinguishing patients more likely to develop
MS. Compared to clinical attacks, serial imaging may not lead to an earlier diagnosis in ATM patients with normal brain MRI. 相似文献
189.
190.
White PL Barton R Guiver M Linton CJ Wilson S Smith M Gomez BL Carr MJ Kimmitt PT Seaton S Rajakumar K Holyoake T Kibbler CC Johnson E Hobson RP Jones B Barnes RA 《The Journal of molecular diagnostics : JMD》2006,8(3):376-384
The limitations of classical diagnostic methods for invasive fungal infections (IFIs) have led to the development of molecular techniques to aid in the detection of IFIs. Despite good published performance, interlaboratory reproduction of these assays is variable, and no consensus has been reached for an optimal method. This publication describes the first multicenter study of polymerase chain reaction methods, for the detection of Aspergillus and Candida species, currently used in the UK and Ireland by distribution and analysis of multiple specimen control panels. All three Candida methods were comparable, achieving a satisfactory level of detection (10 cfu), and the method of preference was dependent on the requirements of the particular laboratory. The results for the five Aspergillus assays were more variable, but two methods (2Asp and 4Asp) were superior (10(1) conidia). Formally, the overall performances of the two Aspergillus assays were comparable (kappa statistic = 0.77). However, on the Roche LightCycler, there was a clear sample-type effect that greatly reduced the detection limit of the 4Asp method when testing whole blood samples. Therefore, the preferred Aspergillus method relied on the amplification platform available to the user. This study represents the initial process to achieve a consensus method for the diagnosis of IFIs. 相似文献