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21.
P. Sabbah C. Brosset P. Imbert G. Bonardel P. Jeandel J. F. Briant 《Neuroradiology》1997,39(10):708-710
We report a case of human African trypanosomiasis caused by Trypanosoma brucei rhodesiense. After the febrile period of parasite dissemination, the patient had meningeal involvement but normal CT. MRI showed the appearances
of meningitis. After two periods of arsenical treatment, a severe encephalopathy occurred suggesting post-therapeutic reactive
encephalitis (PTRE). Nevertheless, T2-weighted MRI showed no oedema, but focal bilateral high signal areas in the white matter.
PTRE was excluded and a third course of treatment was undertaken. The lesions progressively disappeared.
Received: 3 September 1996 Accepted: 30 January 1997 相似文献
22.
C. A. Reynard P. Calain G. P. Pizzolato Dr. J. C. Chevrolet 《Intensive care medicine》1992,18(4):247-249
We report the first case of lethal intracranial haemorrhage complicating a treatment by rt-PA in a patient presenting with a simultaneous staphylococcal septicemia with meningoencephalitis and an acute myocardial infarction with cardiogenic shock. The presence of microvascular lesions in the central nervous system seems to be important risk factor for intracranial haemorrhage and we recommend extreme caution in the use of thrombolytic treatment in septicemic patients with acute myocardial infarction, particularly when neurological symptoms are present. 相似文献
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病毒性心肌炎心肌线粒体结构功能变化及大剂量维生素C干预作用 总被引:3,自引:0,他引:3
目的:探讨病毒性心肌炎(VMC)小鼠心肌线粒体结构和功能,并用大剂量维生素C进行干预。方法:雄性Balb/c小鼠随机分为柯萨奇B3病毒(CVB3)感染组(IG)、CVB3感染加大剂量维生素C治疗组(IVG)和对照组(CG)。采用电镜和形态计量学方法观察心肌线粒体形态、数量和膜磷脂定位,用酶细胞化学法分析心肌线粒体细胞色素氧化酶(CCO)和琥珀酸脱氢酶(SDH)活性。结果:IG小鼠心肌线粒体大量破坏,CCO和SDH活性降低,膜磷脂严重缺失、定位改变(P <0.05~ 0.01)。不同时相点IVG上述各项指标均较IG显著改善(P <0.05~0.01)。结论:VMC心肌线粒体结构严重破坏、功能明显下降,大剂量维生素C能有效保护心肌线粒体结构和功能。 相似文献
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Inhibition of nitric oxide synthase attenuates blood-brain barrier disruption during experimental meningitis 总被引:10,自引:0,他引:10
Increased permeability of the blood-brain (B-B) barrier is observed during meningitis. Preventing B-B barrier alterations is important because adverse neurological outcomes are correlated with breeches in barrier integrity. It was hypothesized that pathological production of nitric oxide (NO) contributes to B-B barrier disruption during meningitis in the rat. Experimental meningitis was induced by intracisternal (i.c.) administration of lipopolysaccharides (LPS) or vehicle. Groups of rats were concomitantly infused intravenously (i.v.) with saline or the NO synthase inhibitor, aminoguanidine (AG). Eight h after i.c. dosing, B-B barrier alterations were quantitated pharmacokinetically using [14C]sucrose. Serum and regional brain tissues were obtained 0–30 min after tracer dosing and sucrose influx transfer coefficients ( Kin (app)) were calculated from the brain tissue data. Compared to the control groups (i.c. vehicle/i.v. saline), the Kin (app) of the i.c. LPS/i.v. saline group increased 1.6–2.1-fold in various brain regions, thus confirming previous observations of increased [14C]sucrose barrier penetration during meningeal inflammation. Remarkably, i.v. administration of AG to i.c. LPS-treated rats significantly inhibited meningeal NO synthesis and decreased Kin (app) permeability alterations in the B-B barrier, compared to i.c. LPS/i.v. saline-treated rats. Regional brain Kin (app) estimates in the i.c. LPS/i.v. AG group were similar to control groups (i.c. vehicle/i.v. AG and i.c. vehicle/i.v. saline). In conclusion, these data suggest the general concept that excessive NO production during neuroinflammatory diseases contributes to disruption of the blood-brain barrier. 相似文献
27.
Summary The effect of the complement-derived polypeptide C3adesArg as a mediator of inflammation in the central nervous system was examined. Twenty-five anesthetized cats received 4 mg of this polypeptide by intraventricular injection, 20 cats who served as controls received saline. Cerebrospinal fluid (CSF) was sampled 3 h after intraventricular injection and the brains were removed. For assessment of the permeability of the blood-brain barrier the CSF penetration of four antibiotics, which were given intravenously, was measured. Five control animals were employed for each antibiotic (tobramycin, ampicillin, imipenem, fosfomycin), whereas six C3adesArg-treated animals were used for each antibiotic and seven for tobramycin. Besides CSF levels of glucose, the prostanoids 6-keto-prostaglandin F1, thromboxane B2 and prostaglandin E2 were measured. The morphological examinations in the CSF sediments and histological brain sections in the C3adesArg-treated animals disclosed a distinct inflammation with leptomeningeal and perivascular infiltration of polymorphonuclear granulocytes compared to normal findings in the controls. The CSF/serum ratios of all of the antibiotics were markedly elevated compared to controls, indicating a blood-brain barrier disruption. The levels of all prostanoids were significantly higher in the treatment group than in the control group, whereas the glucose levels were lower. These findings are in accordance with a granulocytic meningitis as seen in some infections at the acute stage. It is concluded that C3adesArg acts as a mediator of inflammation in the central nervous system. 相似文献
28.
Cytomegaloviruses encode homologs of cellular immune effector proteins, including chemokines (CKs) and CK receptor-like G protein-coupled receptors (GPCRs). Sequence of the guinea pig cytomegalovirus (GPCMV) genome identified an open reading frame (ORF) which predicted a 101 amino acid (aa) protein with homology to the macrophage inflammatory protein (MIP) subfamily of CC (β) CKs, designated GPCMV-MIP. To assess functionality of this CK, recombinant GPCMV-MIP was expressed in HEK293 cells and assayed for its ability to bind to and functionally interact with a variety of GPCRs. Specific signaling was observed with the hCCR1 receptor, which could be blocked with hMIP −1α in competition experiments. Migration assays revealed that GPCMV-MIP was able to induce chemotaxis in hCCR1-L1.2 cells. Antisera raised against a GST-MIP fusion protein immunoprecipitated species of ∼12 and 10 kDa from GPCMV-inoculated tissue culture lysates, and convalescent antiserum from GPCMV-infected animals was immunoreactive with GST-MIP by ELISA assay. These results represent the first substantive in vitro characterization of a functional CC CK encoded by a cytomegalovirus. 相似文献
29.
K. Nagamani Manisha Rani Vishnuvardhan Reddy Panduranga Rao Sushma Rajyalakshmi Sunitha Pakalapaty 《Indian journal of medical microbiology》2022,40(1):12-17
PurposeNoroviruses are common viral agents in acute diarrhea in all age groups worldwide. Norovirus has been classified into 10 genogroups, GI to GX with over 48 genotypes among them the GII.4 genotype has evolved over time with a clear pattern of periodic variant replacement. Immunity is strain or genotype specific with little or no protection conferred across genogroups. The present study was aimed to determine the epidemiology, prevalent genotypes of norovirus in children below five years of age in the Hyderabad region, India.MethodsThe stool samples and clinical data were collected from 458 children below 5 years of age comprising of cases with acute gastroenteritis (n ?= ?366) and a control group (n ?= ?92) admitted to the pediatric ward. All the samples were tested for Norovirus by ELISA and RT-PCR. Sequencing was done for predominant strains.Results10.3% (n ?= ?38) of cases and 3.2% (n ?= ?3) of the control group were found to be Norovirus positive. Predominant genotypes were GII-82.5% followed by GI-12.5%.ConclusionSequencing and Phylogenetic analyses of 20 GII.4 strains was done. All of the isolates are clustered away from published the GII.4 variants thus suggesting the appearance of a new variant. 相似文献
30.