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881.
Sanjay J Pawar Rewati Raman Sharma Santosh D Lad Ebenezer Dev Rama Verma Devadas 《Journal of clinical neuroscience》2002,9(1):76-79
Sellar lesions mainly constitute pituitary adenomas, craniopharyngiomas and benign cysts. Rathke's pouch cyst is a developmental sellar and/or suprasellar cystic lesion lined by a single layer of ciliated cuboidal or columnar epithelium, which rarely be comes symptomatic. The authors present an interesting case of intrasellar Rathke's pouch cyst, with a presenting feature of acute pituitary apoplexy. This was a 19 year old healthy male who had developed sudden headache and visual disturbance. Neuro-radiological imaging revealed a mass in the sella. Via transsphenoidal approach a haemorrhagic intrasellar cystic lesion was removed and was confirmed as a haemorrhagic Rathke's cleft cyst by histopathological examination. Interesting clinical presentations and the neuroimaging findings are described and discussed. 相似文献
882.
Objective.?To evaluate the transplacental effect of allopurinol, which acts as a xanthine oxidase inhibitor and free radical scavenger, on inhibiting the production of superoxides during intermittent partial umbilical cord occlusion.Methods.?Using four chronically instrumented fetal lambs, ewes received 400?mg allopurinol over a period of two hours. Concentrations of allopurinol and oxypurinol in blood samples from mothers and fetuses and fetal brain microdialysis perfusate were measured by HPLC. In another three cases the production of superoxide during intermittent umbilical cord occlusion was studied by measurement of chemiluminescence in perfusate before and after administration of Allopurinol.Results.?(i) Allopurinol concentration in mothers had reached equilibrium by 30?min after starting administration and maintained a concentration about 6?μg/ml. Allopurinol concentration in fetuses increased gradually and reached 2.25?±?0.54?μg/ml at 120?min; (ii) Oxypurinol concentration in both mothers and fetuses increased during administration of allopurinol; (iii) Concentrations of allopurinol and oxypurinol in the perfusates reached 0.32?±?0.12?μg/ml, 0.53?±?0.22?μg/ml at 120min respectively; and (iv) Administration of allopurinol significantly suppressed superoxide production during intermittent partial umbilical cord occlusion.Conclusion.?These results demonstrated a good transfer of allopurinol from mother to fetus and suggested the possibility of intrauterine treatment to inhibit fetal brain damage resulting from increased oxygen free radicals. 相似文献
883.
884.
Dhirendra Singh Yadav Indranil Chattopadhyay Anand Verma Thoudam Regina Devi L. C. Singh Jagannath Dev Sharma Amal Ch. Kataki Sunita Saxena Sujala Kapur 《Tumour biology》2014,35(9):9317-9330
The susceptibility of an individual to oral cancer is mediated by genetic factors and carcinogen-exposure behaviors such as betel quid chewing, tobacco use, and alcohol consumption. This pilot study was aimed to identify the genetic alteration in 100 bp upstream and downstream flanking regions in addition to the exonic regions of 169 cancer-associated genes by using Next Generation sequencing with aim to elucidate the molecular pathogenesis of tobacco- and betel quid-associated oral cancer of Northeast India. To understand the role of chemical compounds present in tobacco and betel quid associated with the progression of oral cancer, single nucleotide polymorphisms (SNPs) and insertion and deletion (Indels) found in this study were analyzed for their association with chemical compounds found in tobacco and betel quid using Comparative Toxogenomic Database. Genes (AR, BRCA1, IL8, and TP53) with novel SNP were found to be associated with arecoline which is the major component of areca nut. Genes (BARD1, BRCA2, CCND2, IGF1R, MSH6, and RASSF1) with novel deletion and genes (APC, BRMS1, CDK2AP1, CDKN2B, GAS1, IGF1R, and RB1) with novel insertion were found to be associated with aflatoxin B1 which is produced by fermented areca nut. Genes (ADH6, APC, AR, BARD1, BRMS1, CDKN1A, E2F1, FGFR4, FLNC, HRAS, IGF1R, IL12B, IL8, NBL1, STAT5B, and TP53) with novel SNP were found to be associated with aflatoxin B1. Genes (ATM, BRCA1, CDKN1A, EGFR, IL8, and TP53) with novel SNP were found to be associated with tobacco specific nitrosamines. 相似文献
885.
Heinrichs WL Srivastava S Montgomery K Dev P 《The Journal of the American Association of Gynecologic Laparoscopists》2004,11(4):450-456
A structured vocabulary is proposed for supporting the design and development of advanced surgical simulators. Nine fundamental surgical instrument-tissue actions or manipulations are defined and common synonyms provided. The vocabulary focuses on "target skills" that are familiar to surgeons, in comparison with "enabling skills" from the lexicon of instructional designers and psychometricians. The adoption of this vocabulary can facilitate communication among surgeons and bioengineers developing "high-fidelity" surgical simulators. 相似文献
886.
Savita Bansal Diwesh Chawla Manushi Siddarth Basu Dev Banerjee Sri Venkata Madhu Ashok Kumar Tripathi 《Clinical biochemistry》2013,46(1-2):109-114
ObjectivesEnhanced formation of advanced glycation end products (AGEs) formed secondary to hyperglycemic conditions has been linked to diabetes mellitus (DM) associated complications. We investigated the clinical relevance of estimating AGEs and their relationship with oxidative stress (OS) and paraoxonase (PON1) activity in type 2 DM (T2DM) in relation to development of vascular complications.Design and MethodsSerum AGEs along with PON1 activity, protein carbonyl (PCO), advanced oxidation protein products (AOPP), lipid peroxidation (MDA), and total thiol (T-SH) were determined in 157 T2DM patients (DM without complications n = 57, DM micro-vascular complications n = 53, DM macro-vascular complications n = 47) and 40 healthy controls.ResultsSerum AGE level increased significantly in various study groups in following manner: healthy control < DM without complications < DM-macro < DM-micro. Logistic regression analysis using diabetic complications as dependent variable showed significant association with AGE level and PON1 activity even after adjustment for confounding factors. Receiver-operating-characteristics curve analysis showed that 2-fold increased in glycation and 50% decrease in PON1 activity may lead to development of vascular complications in diabetic subjects. PCO, AOPP and MDA were higher and PON1 activity was lower in T2DM with complications than those without complications. Among diabetic patients AGEs showed significant positive correlation with HbA1C, MDA, AOPP, and negative correlation with PON1 activity and T-SH.ConclusionHigh serum AGE concentration and low PON1 activity may be considered as additional risk factor for development of vascular complications in T2DM. AGE formation plays significant role in induction of OS in diabetes. 相似文献
887.
Haritha Chelimilla Jasbir S Makker Anil Dev 《World journal of gastrointestinal endoscopy》2013,5(2):74-78
Pneumatosis of the gastrointestinal tract is a rare condition characterized by the presence of air filled cavities in the gastrointestinal tract wall.Its occurrence has been described throughout the gastrointestinal tract from the esophagus to the rectum,however it is most commonly reported in the small intestine.Despite multiple case reports in literature,its pathogenesis still remains unclear.Pneumatosis may be idiopathic or associated with a variety of disorders namely peptic ulcer disease,jejunoileal bypass,intestinal obstruction and non-gastrointestinal disorders like asthma,chronic obstructive pulmonary disease,systemic lupus erythematosus,infectious enteritis,etc.We here present a rare case of pneumatosis of the esophagus diagnosed incidentally at an esophagogastroduodenoscopy(EGD).A 78-year-old asymptomatic woman underwent EGD and colonoscopy at our hospital for evaluation of anemia.Few months prior to EGD,she had undergone excision of laryngocele at our hospital.EGD revealed extensive submucosal blebs distributed throughout the esophagus,otherwise unremarkable stomach and duodenum.Colonoscopy showed a tubular adenomatous polyp.Since our patient was asymptomatic she did not require any surgical intervention.Management of pneumatosis depends on the underlying cause. 相似文献
888.
A Carmona G Devès S Roudeau P Cloetens S Bohic R Ortega 《ACS chemical neuroscience》2010,1(3):194-203
Chronic exposure to manganese results in neurological symptoms referred to as manganism and is identified as a risk factor for Parkinson's disease. In vitro, manganese induces cell death in the dopaminergic cells, but the mechanisms of manganese cytotoxicity are still unexplained. In particular, the subcellular distribution of manganese and its interaction with other trace elements needed to be assessed. Applying synchrotron X-ray fluorescence nanoimaging, we found that manganese was located within the Golgi apparatus of PC12 dopaminergic cells at physiologic concentrations. At increasing concentrations, manganese accumulates within the Golgi apparatus until cytotoxic concentrations are reached resulting in a higher cytoplasmic content probably after the Golgi apparatus storage capacity is exceeded. Cell exposure to manganese and brefeldin A, a molecule known to specifically cause the collapse of the Golgi apparatus, results in the striking intracellular redistribution of manganese, which accumulates in the cytoplasm and the nucleus. These results indicate that the Golgi apparatus plays an important role in the cellular detoxification of manganese. In addition manganese exposure induces a decrease in total iron content, which could contribute to the overall neurotoxicity. 相似文献
889.
We present data of two patients with endomyocardial biopsy proven acute myocarditis presenting with clinical and electrocardiographic features of acute transmural myocardial infarction. Coronary angiograms were normal in both of them. The presentation of inflammatory myocarditis as myocardial infarction is emphasized. 相似文献
890.
S Shrivastava V Dev R S Vasan G S Das M Rajani 《The American journal of cardiology》1991,67(9):892-894